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Surgery_Schwartz. connection (TAPVC) and sutureless repair of TAPVC. In the sutureless techniques, there are no sutures placed in the fragile veins themselves. Rather, the pericardial flaps are used to create a “well” for the pulmonary venous return (bottom inset). Early and late extrinsic stenosis are thought to be reduced using this latter technique.Brunicardi_Ch20_p0751-p0800.indd 76722/02/19 2:55 PM 768SPECIFIC CONSIDERATIONSPART IIat 11 years after repair, with increased risk associated with mixed connection and postoperative pulmonary venous obstruction. A study from the Hospital for Sick Children, Toronto, showed a lower incidence of reoperation in the sutureless technique com-pared to conventional pulmonary venous confluence–left atrial anastomosis.86 However, there was no statistically significant difference suggesting similar results between the strategies. Although the sutureless technique appears to have favorable outcomes at primary repair for TAPVC, long-term follow-up is necessary to


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Surgery_Schwartz. difference suggesting similar results between the strategies. Although the sutureless technique appears to have favorable outcomes at primary repair for TAPVC, long-term follow-up is necessary to evaluate the occurrence of arrhythmias, such as complete heart block and atrial tachycardia, since an incision on the atrial septum and atrial wall is more invasive compared to the conventional technique.The most significant postoperative complication of TAPVC repair is pulmonary venous obstruction (Figure 20-21), which occurs 9% to 11% of the time, regardless of the surgi-cal technique employed. Mortality varies between 30% and 45%, and alternative catheter interventions do not offer defini-tive solutions.80 Recurrent pulmonary venous obstruction can be localized at the site of the pulmonary venous anastomosis (extrinsic), which usually can be cured with patch enlargement or balloon dilatation, or it may be secondary to endocardial thickening of the pulmonary venous ostia frequently


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Surgery_Schwartz. venous anastomosis (extrinsic), which usually can be cured with patch enlargement or balloon dilatation, or it may be secondary to endocardial thickening of the pulmonary venous ostia frequently resulting in diffuse pulmonary venous sclerosis (intrinsic), which car-ries a 66% mortality rate because few good solutions exist.77 More commonly, postrepair left ventricular dysfunction can occur as the noncompliant LV suddenly is required to handle an increased volume load from redirected pulmonary venous return. This can manifest as an increase in pulmonary artery pressure but is distinguishable from primary pulmonary hyper-tension (another possible postoperative complication following repair of TAPVC) from the elevated left atrial pressure and LV dysfunction along with echocardiographic evidence of poor LV contractility. In pulmonary hypertension, the left atrial pressure may be low, the LV may appear “underfilled” (by echocardiog-raphy), and the RV may appear dilated. In either case,


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Surgery_Schwartz. of poor LV contractility. In pulmonary hypertension, the left atrial pressure may be low, the LV may appear “underfilled” (by echocardiog-raphy), and the RV may appear dilated. In either case, postop-erative support for a few days with extracorporeal membrane oxygenation may be lifesaving, and TAPVC should be repaired in centers that have this capacity.Some investigators have speculated that preoperative pul-monary venous obstruction is associated with increased medial thickness within the pulmonary vasculature, which may predis-pose these infants to intrinsic pulmonary venous stenosis despite adequate pulmonary venous decompression.82 The majority of studies demonstrating that preoperative pulmonary venous obstruction is a predictor of subsequent need for reoperation to correct recurrent pulmonary venous obstruction lend credence to this notion.Cor TriatriatumAnatomy. Cor triatriatum is a rare congenital heart defect char-acterized by the presence of a fibromuscular diaphragm that


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Surgery_Schwartz. pulmonary venous obstruction lend credence to this notion.Cor TriatriatumAnatomy. Cor triatriatum is a rare congenital heart defect char-acterized by the presence of a fibromuscular diaphragm that par-titions the left atrium into two chambers: a superior chamber that receives drainage from the pulmonary veins, and an inferior chamber that communicates with the mitral valve and the LV (Fig. 20-22). An ASD frequently exists between the superior chamber and the right atrium, or, more rarely, between the right atrium and the inferior chamber.Pathophysiology and Diagnosis. Cor triatriatum results in obstruction of pulmonary venous return to the left atrium. The degree of obstruction is variable and depends on the size of fen-estrations present in the left atrial membrane, the size of the ASD, and the existence of other associated anomalies. If the communication between the superior and inferior chambers is <3 mm, patients usually are symptomatic during the first year of life. The afflicted


Surgery_Schwartz

Surgery_Schwartz. the existence of other associated anomalies. If the communication between the superior and inferior chambers is <3 mm, patients usually are symptomatic during the first year of life. The afflicted infant will present with the stigmata of low cardiac output and pulmonary venous hypertension, as well as congestive heart failure and poor feeding.Physical examination may demonstrate a loud pulmonary S2 sound and a right ventricular heave, as well as jugular venous distention and hepatomegaly. Chest radiography will show car-diomegaly and pulmonary vascular prominence, and the ECG will suggest right ventricular hypertrophy. Two-dimensional echocardiography provides a definitive diagnosis in most cases, with catheterization necessary only when echocardiographic evaluation is equivocal.Therapy. Operative treatment for cor triatriatum is fairly simple. CPB and cardioplegic arrest are used. A right atriotomy usually Figure 20-21. Angiogram showing the discrete stenosis (‘*’) of the right-sided


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Surgery_Schwartz. treatment for cor triatriatum is fairly simple. CPB and cardioplegic arrest are used. A right atriotomy usually Figure 20-21. Angiogram showing the discrete stenosis (‘*’) of the right-sided pulmonary veins after conventional repair for supra-cardiac type TAPVC.Figure 20-22. Echocardiogram (apical 4 chamber view) showing the discrete membrane (‘*’) in a patient with Cor triatritum.Brunicardi_Ch20_p0751-p0800.indd 76822/02/19 2:55 PM 769CONGENITAL HEART DISEASECHAPTER 20allows access to the left atrial membrane through the existing ASD because it is dilated secondary to communication with the pulmonary venous chamber. The membrane is then excised, tak-ing care not to injure the mitral valve or the interatrial septum, and the ASD is closed with a patch. Alternatively, if the right atrium is small, the membrane can be exposed through an inci-sion directly into the superior left atrial chamber, just anterior to the right pulmonary veins. Surgical results are uniformly excel-lent for


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Surgery_Schwartz. is small, the membrane can be exposed through an inci-sion directly into the superior left atrial chamber, just anterior to the right pulmonary veins. Surgical results are uniformly excel-lent for this defect, with survival approaching 100%.The utility of catheter-based intervention for this diagnosis remains controversial, although there have been some reports of successful balloon dilatation.87Aortopulmonary WindowEmbryology and Anatomy. Aortopulmonary window (APW) is a rare congenital lesion, occurring in about 0.2% of patients, characterized by incomplete development of the septum that normally divides the truncus into the aorta and the pulmonary artery88In the vast majority of cases, APW occurs as a single defect of minimal length, which begins a few millimeters above the semilunar valves on the left lateral wall of the aorta (Fig. 20-23). Coronary artery anomalies, such as aberrant origin of the right or left coronary artery from the main pulmonary artery, are occa-sionally


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Surgery_Schwartz. valves on the left lateral wall of the aorta (Fig. 20-23). Coronary artery anomalies, such as aberrant origin of the right or left coronary artery from the main pulmonary artery, are occa-sionally present.Pathophysiology and Diagnosis. The dominant pathophysi-ology of APW is that of a large left-to-right shunt with increased pulmonary flow and the early development of congestive heart failure. Like other lesions with left-to-right flow, the magnitude of the shunt is determined by both the size of the defect and the pulmonary vascular resistance.Infants with APW present with frequent respiratory tract infections, tachypnea with feeding, and failure to thrive. Cya-nosis usually is absent because these infants deteriorate prior to the onset of significant pulmonary hypertension. The rapid decline with this defect occurs because shunt flow continues during both phases of the cardiac cycle, which limits systemic perfusion and increases ventricular work.89The diagnosis of APW begins with


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Surgery_Schwartz. decline with this defect occurs because shunt flow continues during both phases of the cardiac cycle, which limits systemic perfusion and increases ventricular work.89The diagnosis of APW begins with the physical exami-nation, which may demonstrate a systolic flow murmur, a hyperdynamic precordium, and bounding peripheral pulses. The chest radiograph will show pulmonary overcirculation and cardiomegaly, and the ECG will usually demonstrate either left ventricular hypertrophy or biventricular hypertrophy. Echocar-diography (Fig. 20-24) can detect the defect and also provide information about associated anomalies. Retrograde aortogra-phy will confirm the diagnosis but is rarely necessary.Therapy. All infants with APW require surgical correction once the diagnosis is made. Repair is undertaken through a median sternotomy and the use of CPB. The pulmonary arteries are occluded once the distal aorta is cannulated, and a transaor-tic repair using a prosthetic patch for pulmonary artery


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Surgery_Schwartz. through a median sternotomy and the use of CPB. The pulmonary arteries are occluded once the distal aorta is cannulated, and a transaor-tic repair using a prosthetic patch for pulmonary artery closure is then carried out. The coronary ostia must be carefully visual-ized and included on the aortic side of the patch. Alternatively, a two-patch technique can be used, which may eliminate recurrent fistulas from suture line leaks that occasionally occur with the single-patch method.90Results. Results are generally excellent, with an operative mortality in most large series of less than 5%.Vascular Rings and Pulmonary Artery SlingsVascular rings constitute a group of disorders derived from anomalies that result from abnormal development of the aortic arches resulting in compression of the trachea or esophagus. The surgical management of vascular rings dates back to 1945 when Dr. Gross described the surgical management of a kid with double aortic arch.91 Most children present with symptoms


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Surgery_Schwartz. or esophagus. The surgical management of vascular rings dates back to 1945 when Dr. Gross described the surgical management of a kid with double aortic arch.91 Most children present with symptoms during the first few months of life. Vascular rings can be com-plete (e.g., double aortic arch, right aortic arch with left liga-ment) or partial (e.g., innominate artery compression syndrome, pulmonary artery sling).Anatomy. The embryologic basis of vascular rings involves the development of six pairs of aortic arches and the dorsal and ventral aortae. The development of a specific type of vascular ring depends of the deletion or preservation of a specific seg-ment of these structures. The persistence of the right and left fourth arches leads to the development of double aortic arch. Persistence of the fourth right aortic arch and the involution of the left fourth arch leads to the development of a right aor-tic arch system with various combinations of mirror imaging Figure 20-23. Cartoon


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Surgery_Schwartz. of the fourth right aortic arch and the involution of the left fourth arch leads to the development of a right aor-tic arch system with various combinations of mirror imaging Figure 20-23. Cartoon depicting the various types of aortopulmonary window. (Used with permission from Nicholas Clarke MD.)Figure 20-24. Echo demonstrating an aortopulmonary window (‘*’).Type IType IIType IIIBrunicardi_Ch20_p0751-p0800.indd 76922/02/19 2:55 PM 770SPECIFIC CONSIDERATIONSPART IIbranching, aberrant subclavian arteries or with a left-sided liga-mentum arterisum. When the developing left lung captures its blood supply from the right sixth arch caudad to the tracheo-bronchial tree, it leads to the development of a pulmonary artery sling. The left pulmonary artery arises from the right pulmonary artery and then wraps around the trachea and esophagus forming a “sling.”92 The pathophysiology of innominate artery compres-sion syndrome is not very well understood.Pathophysiology and Diagnosis. The


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Surgery_Schwartz. and then wraps around the trachea and esophagus forming a “sling.”92 The pathophysiology of innominate artery compres-sion syndrome is not very well understood.Pathophysiology and Diagnosis. The symptoms associated with vascular rings include respiratory distress, barking cough, stridor, apnea, dysphagia, and recurrent respiratory tract infec-tions. The diagnosis often requires a high index of suspicion. Minor respiratory tract infections may precipitate serious respi-ratory distress. The work up includes chest X-rays, echocardiog-raphy, bronchoscopy, CT scan (Fig. 20-25), MRI (Fig. 20-26), and, rarely, cardiac catheterization. Chest X-rays show the rela-tionship of the aortic arch to the trachea. Tracheal compression can be better evaluated using lateral films. Unilateral hyperinfla-tion of the lung is sometimes seen and is often associated with a pulmonary artery sling (Fig. 20-27). PA slings (Fig. 20-28) are often associated with complete tracheal rings necessitating a bronchoscopy


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Surgery_Schwartz. of the lung is sometimes seen and is often associated with a pulmonary artery sling (Fig. 20-27). PA slings (Fig. 20-28) are often associated with complete tracheal rings necessitating a bronchoscopy when this diagnosis is made (Fig. 20-29). Patients with dysphagia require a barium esophagogram as a part of their work-up (Fig. 20-30).Treatment. All symptomatic patients should undergo surgery. On close questioning nearly all patients are symptomatic.93 The treatment varies depending on the type of vascular ring. A left posterolateral thoracotomy provides good exposure to most types. A right thoracotomy is often used for innominate artery compression syndrome, and a median sternotomy often with cardiopulmonary bypass is used to treat pulmonary artery slings with or without associated complete tracheal rings. The out-comes and results for vascular rings are excellent (Fig. 20-31). Video-assisted thoracoscopic approaches have been developed for the management of these conditions.94-96 The


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Surgery_Schwartz. tracheal rings. The out-comes and results for vascular rings are excellent (Fig. 20-31). Video-assisted thoracoscopic approaches have been developed for the management of these conditions.94-96 The criticism often stated involves retraction of vascular structures into the medias-tinum and losing control of the stumps prior to definitve control leading to exsanguination.96DEFECTS REQUIRING PALLIATIONTricuspid AtresiaTricuspid atresia occurs in 2% to 3% of patients with CHD and is characterized by atresia of the tricuspid valve. This results in discontinuity between the right atrium and RV. The RV is generally hypoplastic, and left-heart filling is dependent on an ASD. Tricuspid atresia is the most common form of the single-ventricle complex, indicating that there is functionally only one ventricular chamber.Anatomy. As mentioned, tricuspid atresia results in a lack of communication between the right atrium and the RV, and in the 5Figure 20-25. CT angiogram showing the four artery sign


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Surgery_Schwartz. chamber.Anatomy. As mentioned, tricuspid atresia results in a lack of communication between the right atrium and the RV, and in the 5Figure 20-25. CT angiogram showing the four artery sign classic of double aortic arch.Figure 20-26. MRI showing a double aortic arch.Figure 20-27. Unilateral hyperinflation of the left lung associ-ated with a rare vascular ring: left ascending aorta and right sided descending aorta.Figure 20-28. CT angiogram showing a PA sling. Note the LPA wrapping around behind the trachea.Brunicardi_Ch20_p0751-p0800.indd 77022/02/19 2:55 PM 771CONGENITAL HEART DISEASECHAPTER 20majority of patients there is no identifiable valve tissue or rem-nant.98 The right atrium is generally enlarged and muscular, with a fibrofatty floor. An unrestrictive ASD is usually present. The LV is often enlarged as it receives both systemic and pulmonary blood flow, but the left AV valve is usually normal.The RV, however, is usually severely hypoplastic, and there is sometimes a VSD in


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Surgery_Schwartz. LV is often enlarged as it receives both systemic and pulmonary blood flow, but the left AV valve is usually normal.The RV, however, is usually severely hypoplastic, and there is sometimes a VSD in its trabeculated or infundibular portion. In many cases, the interventricular communication is a site of obstruction to pulmonary blood flow, but obstruction may also occur at the level of the outlet valve or in the subval-vular infundibulum.99 In most cases, pulmonary blood flow is dependent on the presence of a PDA, and there may be no flow into the pulmonary circulation except for this PDA.Tricuspid atresia is classified according to the relationship of the great vessels and by the degree of obstruction to pulmo-nary blood flow. Because of the rarity of tricuspid atresia with transposed great arteries, we will restrict our discussion to tri-cuspid atresia with normally related great vessels.Pathophysiology. The main pathophysiology in tricuspid atresia is that of a univentricular heart


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Surgery_Schwartz. arteries, we will restrict our discussion to tri-cuspid atresia with normally related great vessels.Pathophysiology. The main pathophysiology in tricuspid atresia is that of a univentricular heart of left ventricular morphology. That is, the LV must receive systemic blood via the interatrial communication and then distribute it to both the pulmonary circulation and the systemic circulation. Unless there is a VSD (as is found in some cases), pulmonary flow is dependent on the presence of a PDA. As the ductus begins to close shortly after birth, infants become intensely cyanotic. Reestablishing ductal patency (with PGE1) restores pulmonary blood flow and stabilizes patients for surgical intervention. Pulmonary hypertension is unusual in tricuspid atresia. However, occasional patients have a large VSD between the LV and the infundibular portion of the RV (just below the pulmonary valve). If there is no obstruction at the level of this VSD or at the valve, these infants may actually


Surgery_Schwartz

Surgery_Schwartz. a large VSD between the LV and the infundibular portion of the RV (just below the pulmonary valve). If there is no obstruction at the level of this VSD or at the valve, these infants may actually present with heart failure from excessive pulmonary blood flow. Regardless of whether these infants are “ductal-dependent” for pulmonary blood flow or have pulmonary blood flow provided across a VSD, they will be cyanotic since the obligatory right-to-left shunt at the atrial level will provide complete mixing of systemic and pulmonary venous return so that the LV ejects a hypoxemic mixture into the aorta.Diagnosis. The signs and symptoms of tricuspid atresia are dependent on the underlying anatomic variant, but most infants are cyanotic and hypoxic as a result of decreased pulmonary blood flow and the complete mixing at the atrial level. When pulmonary blood flow is provided through a VSD, there may be a prominent systolic murmur. Tricuspid atresia with pulmonary blood flow from a PDA may


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Surgery_Schwartz. and the complete mixing at the atrial level. When pulmonary blood flow is provided through a VSD, there may be a prominent systolic murmur. Tricuspid atresia with pulmonary blood flow from a PDA may present with the soft, continuous murmur of a PDA in conjunction with cyanosis.In the minority of patients with tricuspid atresia, symp-toms of congestive heart failure will predominate. This is often related to excessive flow across a VSD. The natural history of the muscular VSDs in these infants is that they will close and the congestive heart failure will dissipate and transform into cyano-sis with reduced pulmonary blood flow. Chest radiography will show decreased pulmonary vascularity. The ECG is strongly suggestive because uncharacteristic left axis deviation will be present, due to underdevelopment of the RV. Two-dimensional echocardiography readily confirms the diagnosis and the ana-tomic subtype. (Fig 20-32)Treatment. The treatment for tricuspid atresia in the earlier era of


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Surgery_Schwartz. underdevelopment of the RV. Two-dimensional echocardiography readily confirms the diagnosis and the ana-tomic subtype. (Fig 20-32)Treatment. The treatment for tricuspid atresia in the earlier era of palliation was aimed at correcting the defect in the pul-monary circulation. That is, patients with too much pulmonary flow received a pulmonary band, and those with insufficient flow received a systemic-to-pulmonary artery shunt. Systemic-to-pulmonary artery shunts, or Blalock–Taussig (BT) shunts, were first applied to patients with tricuspid atresia in the 1940s and 1950s.98 Likewise pulmonary artery banding was applied Figure 20-29. Rigid bronchoscopy showing complete tracheal rings in a the patient with pulmonary artery sling.Figure 20-30. Barium esophagogram showing posterior indenta-tion of the esophagus caused by a vascular ring (right aortic arch, aberrant left subclavian artery and left ligamentum).Brunicardi_Ch20_p0751-p0800.indd 77122/02/19 2:55 PM 772SPECIFIC


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Surgery_Schwartz. indenta-tion of the esophagus caused by a vascular ring (right aortic arch, aberrant left subclavian artery and left ligamentum).Brunicardi_Ch20_p0751-p0800.indd 77122/02/19 2:55 PM 772SPECIFIC CONSIDERATIONSPART IIto patients with tricuspid atresia and congestive failure in 1957. However, despite the initial relief of either cyanosis or conges-tive heart failure, long-term mortality was high, as the single ventricle was left unprotected from either volume or pressure overload.99Recognizing the inadequacies of the initial repairs, Glenn described the first successful cavopulmonary anastomosis, an end-to-side right pulmonary artery-to-superior vena cava shunt in 1958, and later modified this to allow flow to both pulmonary arteries.100 This end-to-side right pulmonary artery-to-superior vena cava anastomosis was known as the bidirectional Glenn, and it is the first stage to final Fontan repair in widespread use today (Fig. 20-33). The Fontan repair was a major advancement in the


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Surgery_Schwartz. vena cava anastomosis was known as the bidirectional Glenn, and it is the first stage to final Fontan repair in widespread use today (Fig. 20-33). The Fontan repair was a major advancement in the treatment of CHD, as it essentially bypassed the right heart and allowed separation of the pulmonary and systemic circulations. It was first performed by Fontan in 1971 and con-sisted of a classic Glenn anastomosis, ASD closure, and direct connection of the right atrium to the proximal end of the left pulmonary artery using an aortic homograft.101 The main pul-monary artery was ligated, and a homograft valve was inserted into the orifice of the inferior vena cava.Figure 20-32. Echo showing tricuspid atresia. The ‘*’ demonstrates the membranous tissue instead of the presence of a tricuspid valve.Figure 20-33. Angiogram showing a widely patent Glenn. The SVC (‘*’) is seen draining into the central pulmonary artery.Figure 20-31. Bronchoscopy before and after repair of a vascular ring: right


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Surgery_Schwartz. 20-33. Angiogram showing a widely patent Glenn. The SVC (‘*’) is seen draining into the central pulmonary artery.Figure 20-31. Bronchoscopy before and after repair of a vascular ring: right arch, left descending aorta, and left ligament.Multiple modifications of this initial repair were per-formed over the next 20 years. One of the most important was the description by deLeval and colleagues of the creation of an interatrial lateral tunnel that allowed the inferior vena caval blood to be channeled exclusively to the superior vena cava.102 A total cavopulmonary connection could then be accomplished by dividing the superior vena cava and suturing the superior portion to the upper side of the right pulmonary artery and the inferior end to the augmented undersurface of the right pulmonary artery. Pulmonary flow then occurs passively, in a laminar fashion, driven by the central venous pressure. This repair became known as the modified Fontan operation.Another important modification, the


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Surgery_Schwartz. Pulmonary flow then occurs passively, in a laminar fashion, driven by the central venous pressure. This repair became known as the modified Fontan operation.Another important modification, the fenestrated Fontan repair, was introduced in 1988.103 In this procedure, a residual 20% to 30% right-to-left shunt is either created or left unre-paired at the time of cavopulmonary connection to help sustain systemic output in the face of transient elevations in the pulmo-nary vascular resistance postoperatively.103Brunicardi_Ch20_p0751-p0800.indd 77222/02/19 2:55 PM 773CONGENITAL HEART DISEASECHAPTER 20The last notable variation on the original Fontan repair uses an extracardiac prosthetic tube graft (Fig. 20-34), usually 18 to 20 mm in diameter, as the conduit directing inferior vena cava blood to the pulmonary arteries.105 This technique has the advantages of decreasing atrial geometric alterations by avoid-ing intra-atrial suture lines and improving flow dynamics in the systemic venous


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Surgery_Schwartz. to the pulmonary arteries.105 This technique has the advantages of decreasing atrial geometric alterations by avoid-ing intra-atrial suture lines and improving flow dynamics in the systemic venous pathway by maximizing laminar flow. Several investigators have shown a decrease in supraventricular arrhyth-mias, as well as an improvement in ventricular function, which may be secondary to decreased atrial tension and alleviation of chronic elevations in coronary sinus pressure.102,103One potential disadvantage of the extracardiac Fontan is that it delays performance of the Fontan in order to allow placement of a conduit of sufficient size. Despite these innova-tive approaches, the current strategy for operative management still relies on the idea of palliation. Patients are approached in a staged manner, to maximize their physiologic state so that they will survive to undergo a Fontan operation. The therapeu-tic strategy must begin in the neonatal period and should be directed toward


Surgery_Schwartz

Surgery_Schwartz. a staged manner, to maximize their physiologic state so that they will survive to undergo a Fontan operation. The therapeu-tic strategy must begin in the neonatal period and should be directed toward reducing the patient’s subsequent risk factors for a Fontan procedure. Accordingly, small systemic pulmonary shunts, which are usually performed through a median sternot-omy, should be constructed for palliation of ductus-dependent univentricular physiology. This can easily be replaced with a bidirectional Glenn shunt or hemi-Fontan operation at 6 months of life. In non–ductus-dependent univentricular physiology, the infant can be managed medically until primary construction of a bidirectional cavopulmonary anastomosis becomes feasible. This is possible in the majority of cases because the physiologi-cally elevated pulmonary vascular resistance prevents pulmo-nary overcirculation during the neonatal period.The Fontan is usually performed when the child is between 2 and 4 years of age, and


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Surgery_Schwartz. elevated pulmonary vascular resistance prevents pulmo-nary overcirculation during the neonatal period.The Fontan is usually performed when the child is between 2 and 4 years of age, and it is generally successful if the infant was staged properly, with a protected single ventricle, and there is adequate pulmonary artery growth. The pulmonary vascular resistance should be below 4 Wood units, and the ejection frac-tion should be more than 45% to ensure success.106 In patients with high pulmonary artery pressure, fenestration of the atrial baffle may be helpful because their pulmonary vascular resis-tance may preclude adequate cardiac output postoperatively.99,103Results. Recent reports of the Fontan procedure for tricuspid atresia have been encouraging, with an overall survival of 86% and an operative mortality of 2%.107 The main complications following repair are atrial arrhythmias, particularly atrial flutter; conduit obstruction requiring reoperation; protein-losing enter-opathy; and


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Surgery_Schwartz. operative mortality of 2%.107 The main complications following repair are atrial arrhythmias, particularly atrial flutter; conduit obstruction requiring reoperation; protein-losing enter-opathy; and decreased exercise tolerance.A prospective multi-institutional study from the Congeni-tal Heart Surgeons Society reported the outcomes of 150 neo-nates with tricuspid atresia and normally related great vessels.107 Five-year survival was 86%, and by the age of 2 years, 89% had undergone cavopulmonary anastomosis, and 75% of those surviving cavopulmonary anastomosis underwent Fontan opera-tion within 3 years. Competing risks methodology was used in this study to determine the rates of transition to end-states and their associated determinants (Fig. 20-35). Risk factors for death without cavopulmonary anastomosis in this study included the presence of mitral regurgitation and palliation with systemic-to-pulmonary artery shunts not originating from the innominate artery. Factors associated


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Surgery_Schwartz. anastomosis in this study included the presence of mitral regurgitation and palliation with systemic-to-pulmonary artery shunts not originating from the innominate artery. Factors associated with decreased transition rate to cavo-pulmonary anastomosis included patient variables (younger age at admission to a participating institution and noncardiac anom-alies) and procedural variables (larger systemic-to-pulmonary arterial shunt diameter and previous palliation).9Hypoplastic Left Heart SyndromeHLHS comprises a wide spectrum of cardiac malformations, including hypoplasia or atresia of the aortic and mitral valves and hypoplasia of the LV and ascending aorta.108 HLHS has a reported prevalence of 0.2 per 1000 live births and occurs twice as often in boys as in girls. Left untreated, HLHS is invari-ably fatal and is responsible for 25% of early cardiac deaths in neonates.109 However, the recent evolution of palliative surgical procedures has dramatically improved the outlook for patients


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Surgery_Schwartz. invari-ably fatal and is responsible for 25% of early cardiac deaths in neonates.109 However, the recent evolution of palliative surgical procedures has dramatically improved the outlook for patients with HLHS, and an improved understanding of anatomic and physiologic alterations has spurred advances in parallel arenas such as intrauterine diagnosis and fetal intervention, echocardio-graphic imaging, and neonatal critical care.Anatomy. As implied by its name, HLHS involves varying degrees of underdevelopment of left-sided structures (Fig. 20-36), including the LV and the aortic and mitral valves. Thus, HLHS can be classified into four anatomic subtypes based on the val-vular morphology: (a) aortic and mitral stenosis; (b) aortic and mitral atresia; (c) aortic atresia and mitral stenosis; and (d) AS and mitral atresia. Aortic atresia tends to be associated with more severe degrees of hypoplasia of the ascending aorta than does AS.Even in cases without frank aortic atresia, however, the


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Surgery_Schwartz. (d) AS and mitral atresia. Aortic atresia tends to be associated with more severe degrees of hypoplasia of the ascending aorta than does AS.Even in cases without frank aortic atresia, however, the aortic arch is generally hypoplastic and, in severe cases, may even be interrupted. There is an associated coarctation shelf in 80% of patients with HLHS, and the ductus itself is usually quite large, as is the main pulmonary artery.7The segmental pulmonary arteries, however, are small, secondary to reduced intrauterine pulmonary blood flow, which is itself a consequence of the left-sided outflow obstruction (Fig. 20-36). The left atrial cavity is generally smaller than nor-mal and is accentuated because of the leftward displacement of the septum primum. There is almost always an interatrial com-munication via the foramen ovale, which can be large, but more Figure 20-34. Angiogram in a patient with a fenestrated extra-cardiac fontan constructed with a 20 mm Gore-tex tube graft


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Surgery_Schwartz. com-munication via the foramen ovale, which can be large, but more Figure 20-34. Angiogram in a patient with a fenestrated extra-cardiac fontan constructed with a 20 mm Gore-tex tube graft (‘*’).Brunicardi_Ch20_p0751-p0800.indd 77322/02/19 2:55 PM 774SPECIFIC CONSIDERATIONSPART IIcommonly restricts right-to-left flow. In rare cases, there is no atrial-level communication, which can be lethal for these infants because there is no way for pulmonary venous return to cross over to the RV.Associated defects can occur with HLHS, and many of them have importance with respect to operative repair. For example, if a VSD is present, the LV can retain its normal size during development even in the presence of mitral atresia. This is because a right-to-left shunt through the defect impels growth of the LV.110 This introduces the feasibility of biventricular repair for this subset of patients.Although HLHS undoubtedly results from a complex interplay of developmental errors in the early stages


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Surgery_Schwartz. the LV.110 This introduces the feasibility of biventricular repair for this subset of patients.Although HLHS undoubtedly results from a complex interplay of developmental errors in the early stages of cardio-genesis, many investigators have hypothesized that the altered blood flow is responsible for the structural underdevelopment that characterizes HLHS. In other words, if the stimulus for nor-mal development of the ascending aorta from the primordial aortic sac is high-pressure systemic blood flow from the LV through the aortic valve, then an atretic or stenotic aortic valve, which impedes flow and leads to only low-pressure diastolic retrograde flow via the ductus, will change the developmental signals and result in hypoplasia of the downstream structures (Fig. 20-37). Normal growth and development of the LV and mitral valve can be secondarily affected, resulting in hypoplasia or atresia of these structures.108Pathophysiology and Diagnosis. In HLHS, pulmonary venous blood enters


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Surgery_Schwartz. and development of the LV and mitral valve can be secondarily affected, resulting in hypoplasia or atresia of these structures.108Pathophysiology and Diagnosis. In HLHS, pulmonary venous blood enters the left atrium, but atrial systole cannot propel blood across the stenotic or atretic mitral valve into the LV. Thus, the blood is shunted across the foramen ovale into the right atrium, where it contributes to volume loading of the RV. The end result is pulmonary venous hypertension from outflow obstruction at the level of the left atrium, as well as pulmonary overcirculation and right ventricular failure. As the pulmonary vascular resistance falls postnatally, the condition is exacerbated because right ventricular output is preferentially directed away from the systemic circulation, resulting in profound underperfu-sion of the coronary arteries and the vital organs. Closure of the ductus is incompatible with life in these neonates.Neonates with severe HLHS receive all pulmonary,


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Surgery_Schwartz. resulting in profound underperfu-sion of the coronary arteries and the vital organs. Closure of the ductus is incompatible with life in these neonates.Neonates with severe HLHS receive all pulmonary, sys-temic, and coronary blood flow from the RV. Generally, a child with HLHS will present with respiratory distress within the first day of life, and mild cyanosis may be noted. These infants must be rapidly triaged to a tertiary center, and echocardiography should be performed to confirm the diagnosis. Prostaglandin E1 must be administered to maintain ductal patency, and the Figure 20-36. Echo In a patient with HLHS. Note the extremely hypoplastic left ventricle (‘*’).0200.00.40.81.2Years from diagnosis1.62.0406080100Proportion (%) of patients in each stateBDCPA (2 year prevalence = 90%)Dead without BDCPA(2 year prevalence = 5%)Single-stage Fontan(2 year prevalence = 1%)Alive without BDCPA(2 year prevalence = 4%)Figure 20-35. Competing risks depiction of events after diagnosis in 150


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Surgery_Schwartz. without BDCPA(2 year prevalence = 5%)Single-stage Fontan(2 year prevalence = 1%)Alive without BDCPA(2 year prevalence = 4%)Figure 20-35. Competing risks depiction of events after diagnosis in 150 patients with tricuspid atresia. All patients began alive and thereafter migrated to one of four mutually exclusive end states (death, bidirectional cavopulmonary anastomosis [BDCPA], single-stage Fontan completion, or remaining alive without BDCPA) at time-dependent rates defined by the underlying hazard functions. At any point in time, the sum of propor-tions of children in each state is 100%. For example, estimated prevalences after 2 years from diagnosis are as follows: 89% BDCPA, 6% dead without BDCPA, 4% alive without BDCPA, and 1% single-stage Fontan completion. Solid lines represent parametric point estimates; dashed lines enclose 70% confidence intervals; circles with error bars represent nonparametric estimates; numbers in parentheses indicate the estimated propor-tion of patients


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Surgery_Schwartz. point estimates; dashed lines enclose 70% confidence intervals; circles with error bars represent nonparametric estimates; numbers in parentheses indicate the estimated propor-tion of patients in each state at 2 years from diagnosis. (Reproduced with permission from Karamlou T, Ashburn DA, Caldarone CA, et al: Matching procedure to morphology improves outcomes in neonates with tricuspid atresia, J Thorac Cardiovasc Surg. 2005 Dec;130(6):1503-1510.) Brunicardi_Ch20_p0751-p0800.indd 77422/02/19 2:55 PM 775CONGENITAL HEART DISEASECHAPTER 20ventilatory settings must be adjusted to avoid excessive oxygen-ation and increase carbon dioxide tension. These maneuvers will maintain pulmonary vascular resistance and promote improved systemic perfusion.5,7,108 Cardiac catheterization should gener-ally be avoided because it is not usually helpful and might result in injury to the ductus and compromised renal function second-ary to the osmotic dye load.Treatment. In 1983, Norwood and colleagues


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Surgery_Schwartz. be avoided because it is not usually helpful and might result in injury to the ductus and compromised renal function second-ary to the osmotic dye load.Treatment. In 1983, Norwood and colleagues described a two-stage palliative surgical procedure for relief of HLHS111 that was later modified to the currently used three-stage method of palliation.109 Stage 1 palliation, also known as the modified Norwood procedure (Fig. 20-38), bypasses the LV by creating a single outflow vessel, the neoaorta, which arises from the RV.The current technique of arch reconstruction involves completion of a connection between the pulmonary root, the native ascending aorta, and a piece of pulmonary homograft used to augment the diminutive native aorta. There are several modifications of this anastomosis, most notably the Damus-Kaye-Stansel (DKS) anastomosis, which involves dividing both the aorta and the pulmonary artery at the sinotubular junction. The proximal aorta is anastomosed to the proximal


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Surgery_Schwartz. most notably the Damus-Kaye-Stansel (DKS) anastomosis, which involves dividing both the aorta and the pulmonary artery at the sinotubular junction. The proximal aorta is anastomosed to the proximal pulmonary artery, creating a “double-barreled” outlet from the heart. This outlet is anastomosed to the distal aorta, which can be augmented with homograft material if there is an associated coarctation. At the completion of arch reconstruction, a 3.5or 4-mm shunt is placed from the innominate artery to the right pulmonary artery. The interatrial septum is then widely excised, thereby creating a large interatrial communication and prevent-ing pulmonary venous hypertension.The DKS connection, as described earlier, might avoid postoperative distortion of the tripartite connection in the neo-aorta, and thus decrease the risk of coronary insufficiency.112 It can be used when the aorta is 4 mm or larger. Unfortunately, in many infants with HLHS, especially if there is aortic atresia, the aorta


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Surgery_Schwartz. and thus decrease the risk of coronary insufficiency.112 It can be used when the aorta is 4 mm or larger. Unfortunately, in many infants with HLHS, especially if there is aortic atresia, the aorta is diminutive and often less than 2 mm in diameter. The alternate technique available to provide pulmonary blood flow instead of a shunt is a RV-PA conduit often referred to as a “Sano.” It is usually a 5 or 6 mm ribbed Gore-tex graft.113The postoperative management of infants following stage 1 palliation is complex because favorable outcomes depend on establishing a delicate balance between pulmonary and systemic perfusion. Recent literature suggests that these infants require adequate postoperative cardiac output in order to supply both the pulmonary and the systemic circulations and that the use of oxi-metric catheters to monitor mixed venous oxygen saturation (Svo2) aids clinicians in both the selection of inotropic agents and in ventilatory management.114 Introduction of a shunt between


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Surgery_Schwartz. of oxi-metric catheters to monitor mixed venous oxygen saturation (Svo2) aids clinicians in both the selection of inotropic agents and in ventilatory management.114 Introduction of a shunt between the RV and the pulmonary artery (Sano shunt) dimin-ishes the diastolic flow created by the modified BT shunt and may augment coronary perfusion, resulting in improved postop-erative cardiac function.113 A recent prospective, randomized, multi-institutional trial sponsored by the National Institutes of Health, the Systemic Ventricle Reconstruction (SVR) trial, com-pared the outcomes of neonates having either a modified Blalock–Taussig shunt (MBTS) or a Sano shunt.115 The SVR trial demonstrated that transplantation-free survival 12 months after randomization was higher with the Sano shunt than with the MBTS (74% vs. 64%, P = .01). However, the Sano shunt group had more unintended interventions (P = .003) and complications (P = .002). Right ventricular size and function at the age of 14 months


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Surgery_Schwartz. the MBTS (74% vs. 64%, P = .01). However, the Sano shunt group had more unintended interventions (P = .003) and complications (P = .002). Right ventricular size and function at the age of 14 months and the rate of nonfatal serious adverse events at the age of 12 months were similar in the two groups. Data collected over a mean (± standard deviation) follow-up period of 32 ± 11 months showed a nonsignificant difference in transplanta-tion-free survival between the two groups (P = .06).115Since the initial SVR publications in 2010, the 3-year and 6-year results have been analyzed. At 3 years, the com-bined death and cardiac transplantation rates for the RVPAS vs. MBTS groups were 33% vs. 39% (P = 0.14). When all available data were examined by Kaplan-Meier analysis (mean follow-up 4.4 ± 1.0 years), there was also no difference between groups (log rank P = 0.11). Overall, there were 100 deaths and 10 trans-plantations in the MBTS cohort and 86 deaths and 11 transplan-tations in the RVPAS


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Surgery_Schwartz. years), there was also no difference between groups (log rank P = 0.11). Overall, there were 100 deaths and 10 trans-plantations in the MBTS cohort and 86 deaths and 11 transplan-tations in the RVPAS group.116 At 6 years, although the point averages continued to reflect a difference favoring the RVPAS (combined death/transplantation rate, 36%) in comparison with the MBTS (41%), the number of subjects was not sufficient to 6Figure 20-37. Angiogram obtained in a patient with HLSH (AS/MS). Note the extremely diminutive ascending aorta (‘*’).PatchmBTSRPALPAFigure 20-38. Cartoon depicting the Norwood procedure. The anas-tomosis of the aortic and pulmonary valve annulus is not shown. The ascending aorta and hyplastic arch are reconstructed by patch augmentation. The pulmonary blood flow has been provided in this case by a mBTS. (Used with permission from Kelly Rosso MD.)Brunicardi_Ch20_p0751-p0800.indd 77522/02/19 2:55 PM 776SPECIFIC CONSIDERATIONSPART IIdemonstrate a statistically


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Surgery_Schwartz. been provided in this case by a mBTS. (Used with permission from Kelly Rosso MD.)Brunicardi_Ch20_p0751-p0800.indd 77522/02/19 2:55 PM 776SPECIFIC CONSIDERATIONSPART IIdemonstrate a statistically significant difference between the two groups (log rank P = 0.13). Similar to the 3-year results, RVPAS subjects had a higher incidence of any catheter inter-vention (0.38 vs. 0.23 interventions/patient-year, P <0.001), including balloon angioplasty (P = 0.014), stent (P = 0.009), and coiling (P <0.001).113,114 Currently, there remains an ongoing controversy regarding MBTS vs. RV-PA conduit as the source of pulmonary blood flow after the Norwood operation.119,120Although surgical palliation with the Norwood procedure is still the mainstay of therapy for infants with HLHS, a combined surgical and percutaneous option (hybrid procedure), which con-sists of bilateral pulmonary artery banding and placement of a ductal stent, has emerged as a promising alternative that obviates the need for CPB


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Surgery_Schwartz. percutaneous option (hybrid procedure), which con-sists of bilateral pulmonary artery banding and placement of a ductal stent, has emerged as a promising alternative that obviates the need for CPB in the fragile neonatal period.121,122 The hybrid procedure is performed in a “hybrid suite,” incorporating both advanced fluoroscopic imaging facilities combined with com-plete operating room capabilities. A 3or 3.5-mm PTFE tube graft is cut to a width of 3 to 4 mm and used as the bands on the branch pulmonary arteries, placed just distal to the main pulmo-nary artery. The ductal stent is then positioned in order to cover all ductal tissue and is deployed through a purse-string suture in the main pulmonary artery. A reverse systemic-to-pulmonary shunt is considered in patients with aortic atresia and preductal coarctation to improve coronary perfusion; however, a recent study demonstrated no difference in survival between those with and without the shunt.123 The hybrid procedure can also be


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Surgery_Schwartz. and preductal coarctation to improve coronary perfusion; however, a recent study demonstrated no difference in survival between those with and without the shunt.123 The hybrid procedure can also be used as a bridge to heart transplantation in those infants with severe AV valve regurgitation or otherwise unsuitable single-ventricle anatomy.124Following stage 1 palliation, the second surgical proce-dure is the creation of a bidirectional cavopulmonary shunt (Fig. 20-39) or hemi-Fontan, generally at 3 to 6 months of life when the pulmonary vascular resistance has decreased to nor-mal levels. This is the first step in separating the pulmonary and systemic circulations, and it decreases the volume load on the single ventricle. The existing innominate artery-to-pulmonary shunt (or RV-to-pulmonary shunt) or MBTS is eliminated dur-ing the same operation.The third stage of surgical palliation, known as the modi-fied Fontan procedure, completes the separation of the sys-temic and pulmonary


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Surgery_Schwartz. shunt) or MBTS is eliminated dur-ing the same operation.The third stage of surgical palliation, known as the modi-fied Fontan procedure, completes the separation of the sys-temic and pulmonary circulations and is performed between 18 months and 3 years of age, or when the patient experiences increased cyanosis (i.e., has outgrown the capacity to perfuse the systemic circulation with adequately oxygenated blood). This has traditionally required a lateral tunnel within the right atrium to direct blood from the inferior vena cava to the pulmo-nary artery, allowing further relief of the volume load on the RV and providing increased pulmonary blood flow to alleviate cyanosis. More recently, many favor using an extracardiac con-duit (e.g., 18to 20-mm tube graft) to connect the inferior vena cava to the pulmonary artery (Fig. 20-40).Not all patients with HLHS require this three-stage pallia-tive repair. Some infants afflicted with a milder form of HLHS, recently described as hypoplastic left


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Surgery_Schwartz. to the pulmonary artery (Fig. 20-40).Not all patients with HLHS require this three-stage pallia-tive repair. Some infants afflicted with a milder form of HLHS, recently described as hypoplastic left heart complex (HLHC), have aortic or mitral hypoplasia without intrinsic valve stenosis and antegrade flow in the ascending aorta. In this group, a two-ventricle repair can be achieved with reasonable outcome. Tch-ervenkov has published the results with 12 patients with HLHC who underwent biventricular repair at a mean age of 7 days.114 The operative technique consisted of a pulmonary homograft patch aortoplasty of the aortic arch and ascending aorta and closure of the interatrial and interventricular communications. The left heart was capable of sustaining systemic perfusion in 92% of patients, and early mortality was 15.4%. Four patients required reoperations to relieve LVOT obstruction, most com-monly between 12 and 39 months following repair. The group from Boston Children’s Hospital


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Surgery_Schwartz. and early mortality was 15.4%. Four patients required reoperations to relieve LVOT obstruction, most com-monly between 12 and 39 months following repair. The group from Boston Children’s Hospital has been very aggressive in left ventricular recruitment. These operations still carry a high burden of late death and several reoperations.Although the Norwood procedure is the most widely per-formed initial operation for HLHS, transplantation can be used as a first-line therapy and may be preferred when anatomic or physiologic considerations exist that preclude a favorable out-come with palliative repair. Significant tricuspid regurgitation, intractable pulmonary artery hypertension, or progressive right ventricular failure are cases where cardiac replacement may be advantageous. Widespread adaptation of transplantation as SVCLPAAtriumFigure 20-39. Cartoon depicting a bidirectional Glenn. (Used with permission from Kelly Rosso MD.)SVCGore-textube graftAtriumIVCFigure 20-40. Extra cardiac


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Surgery_Schwartz. of transplantation as SVCLPAAtriumFigure 20-39. Cartoon depicting a bidirectional Glenn. (Used with permission from Kelly Rosso MD.)SVCGore-textube graftAtriumIVCFigure 20-40. Extra cardiac fenestrated Fontan. ‘*’ shows the fen-estration. (Used with permission from Kelly Rosso MD.)Brunicardi_Ch20_p0751-p0800.indd 77622/02/19 2:55 PM 777CONGENITAL HEART DISEASECHAPTER 20first-line treatment for HLHS has been limited by improved Norwood survival rates as the operation and preand postop-erative management of the patient have evolved and by lim-ited organ availability. Organ availability should be considered prior to electing transplantation, as 24% of infants died awaiting transplantation in the largest series to date.126,127Results. Outcomes for HLHS are still significantly worse than those for other complex cardiac defects. However, with improvements in perioperative care and modifications in surgical technique, the survival following the Norwood proce-dure now exceeds 90% in


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Surgery_Schwartz. those for other complex cardiac defects. However, with improvements in perioperative care and modifications in surgical technique, the survival following the Norwood proce-dure now exceeds 90% in experienced centers.115-120 The out-come for low-birth-weight infants has improved, but low weight still remains a major predictor of adverse survival, especially when accompanied by significant tricuspid valve insufficiency, a restructive interatrial communication, poor RV function, or extracardiac or chromosomal anomalies.DEFECTS THAT MAY BE PALLIATED OR REPAIREDEbstein’s AnomalyAnatomy. This is a rare defect, occurring in less than 1% of CHD patients. The predominant maldevelopment in this lesion is the inferior displacement of the tricuspid valve into the RV, although Bove128 and others have emphasized the fact that Ebstein’s anomaly is primarily a defect in right ventricular morphology rather than an isolated defect in the tricuspid valve. The anterior leaflet is usually attached in its


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Surgery_Schwartz. emphasized the fact that Ebstein’s anomaly is primarily a defect in right ventricular morphology rather than an isolated defect in the tricuspid valve. The anterior leaflet is usually attached in its normal position to the annulus, but the septal and posterior leaflets are displaced toward the ventricle. This effectively divides the RV into two parts: the inlet portion (atrialized RV) and the outlet portion (true or trabeculated RV) (Fig. 20-41). The atrialized RV is usu-ally thin and dilated. Similarly, the tricuspid annulus and the right atrium are extremely dilated, and the tricuspid valve is usually regurgitant with a “sail-like” leaflet (Fig. 20-42). There is commonly an ASD present, which results in a right-to-left shunt at the atrial level. Occasionally, there is true anatomic pulmonary atresia or milder forms of RVOT obstruction.A Wolff-Parkinson-White (WPW) syndrome (Fig. 20-43) type of accessory pathway with associated preexcitation is pres-ent in 15% of


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Surgery_Schwartz. true anatomic pulmonary atresia or milder forms of RVOT obstruction.A Wolff-Parkinson-White (WPW) syndrome (Fig. 20-43) type of accessory pathway with associated preexcitation is pres-ent in 15% of patients.128Pathophysiology. Right ventricular dysfunction occurs in patients with Ebstein’s anomaly because of two basic mecha-nisms: the inflow obstruction at the level of the atrialized ven-tricle, which produces ineffective RV filling and contractile dysfunction. Inflow obstruction and tricuspid regurgitation, which is exacerbated by progressive annular dilatation, both produce ineffective RV filling. Contractile dysfunction of the RV is a result of a decrease in the number of myocardial fibers, as well as the discordant contraction of the large atrialized portion.The lack of forward flow at the right ventricular level may lead to physiologic or functional pulmonary atresia, and the infant is dependent on ductal patency for survival. All sys-temic venous return must be directed through


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Surgery_Schwartz. the right ventricular level may lead to physiologic or functional pulmonary atresia, and the infant is dependent on ductal patency for survival. All sys-temic venous return must be directed through an ASD to the left atrium, where it can be shunted through the ductus for gas exchange. However, the left ventricular function is usually compromised in infants with severe Ebstein’s anomaly as well because the enormous RV and the to-and-fro flow within the atrialized RV prevent adequate intracardiac mixing. Left ven-tricular function may also be severely compromised in Ebstein’s anomaly because the large RV causes left ventricular compres-sion (Fig. 20-44A,B).Diagnosis. There is a spectrum of clinical presentation in infants with Ebstein’s anomaly that mirrors the anatomic spec-trum of this anomaly. Some infants with less severe forms may present with a mild degree of cyanosis, whereas the onset of clinical symptoms in patients surviving childhood is gradual, with the average age of


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Surgery_Schwartz. anomaly. Some infants with less severe forms may present with a mild degree of cyanosis, whereas the onset of clinical symptoms in patients surviving childhood is gradual, with the average age of diagnosis in the mid-teens.However, the infant with severe atrialization and pulmo-nary stenosis will be both cyanotic and acidotic at birth. The chest radiograph may demonstrate the classic appearance, which 7Figure 20-41. Echo showing a patient with Ebsteins anomaly. Note the inferiorly displaced tricuspid valve (‘*’) and the atrialized por-tion of the RV (arrow).Figure 20-42. Echo in a patient with severe Ebsteins anomaly showing the large ‘sail like’ anterior leaflet (‘*’).Brunicardi_Ch20_p0751-p0800.indd 77722/02/19 2:56 PM 778SPECIFIC CONSIDERATIONSPART IIconsists of a globular “wall-to-wall” heart (Fig. 20-45), similar to that seen with pericardial effusion. The ECG may show right bundle-branch block and right axis deviation. WPW syndrome, as mentioned earlier, is a common finding


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Surgery_Schwartz. heart (Fig. 20-45), similar to that seen with pericardial effusion. The ECG may show right bundle-branch block and right axis deviation. WPW syndrome, as mentioned earlier, is a common finding in these patients. Echocardiography will confirm the diagnosis and provide criti-cal information including tricuspid valvular function, size of the atrialized portion of the RV, degree of pulmonary stenosis, and the atrial size.128The Great Ormond Street Score (GOSE) (Table 20-1),129 which consists of the area of the right atrium plus the area of the atrialized portion of the RV divided by the diastolic area of the remaining cardiac chambers, has been proposed as a useful prognostic tool to stratify neonates with Ebstein’s anomaly. A score of greater than 2 translates into uniformly fatal outcome. Electrophysiology study with radiofrequency ablation is indi-cated in patients with evidence of WPW syndrome or in children Figure 20-43. EKG of a newborn with Ebsteins anomaly and WPW syndrome. Note


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Surgery_Schwartz. Electrophysiology study with radiofrequency ablation is indi-cated in patients with evidence of WPW syndrome or in children Figure 20-43. EKG of a newborn with Ebsteins anomaly and WPW syndrome. Note the pre-excitation (arrow).ABFigure 20-44. A. Echo (short axis view) of a patient with severe Ebsteins anomaly showing the large RV (‘*’) and small LV (arrow) in diastole. B. Echo (short axis view) of a patient with severe Ebsteins anomaly showing the large RV (‘*’) and small ‘pancaked’ LV (arrow) in systole.Brunicardi_Ch20_p0751-p0800.indd 77822/02/19 2:56 PM 779CONGENITAL HEART DISEASECHAPTER 20with a history of supraventricular tachycardia, undefined wide-complex tachycardia, or syncope.Treatment. Surgery is indicated for symptomatic infants and for older children and adults with arrhythmias, progressive cya-nosis, or New York Heart Association class III or IV. How-ever, the operative repair may be different, depending on the patient’s age, because older children usually are


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Surgery_Schwartz. arrhythmias, progressive cya-nosis, or New York Heart Association class III or IV. How-ever, the operative repair may be different, depending on the patient’s age, because older children usually are candidates for a biventricular or one-and-a-half ventricle repair, whereas moder-ate survival has been reported for neonates, using a procedure that converts the anatomy to a single-ventricle physiology, as described by Starnes and coworkers.130The surgical approach in widespread use today for patients surviving infancy was described by Danielson and colleagues in 1992.128,131 This procedure entails excision of redundant right atrial tissue and patch closure of any associated ASD, plication of the atrialized portion of the ventricle with obliteration of the aneurysmal cavity, posterior tricuspid annuloplasty to narrow the tricuspid annulus, reconstruction of the tricuspid valve if the anterior leaflet is satisfactory, or replacement of the tricuspid valve if necessary.131 If the tricuspid


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Surgery_Schwartz. annuloplasty to narrow the tricuspid annulus, reconstruction of the tricuspid valve if the anterior leaflet is satisfactory, or replacement of the tricuspid valve if necessary.131 If the tricuspid valve is not amenable to reconstruction, valve replacement should be considered. Care must be taken when performing the posterior annuloplasty, or during the conduct of tricuspid valve replacement, to avoid the conduction system, because complete heart block can compli-cate this procedure. In addition, patients who demonstrated preoperative evidence of preexcitation should undergo electro-physiologic mapping and ablation.Neonatal Ebstein’s anomaly is a separate entity. Results with surgical correction have been poor, and many neonates are not candidates for operative repair as previously described. Surgical options for the symptomatic neonate include palliative procedures, the one-and-a-half ventricle repair, or conversion to single-ventricle physiology.132 Arguably, the most favorable


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Surgery_Schwartz. Surgical options for the symptomatic neonate include palliative procedures, the one-and-a-half ventricle repair, or conversion to single-ventricle physiology.132 Arguably, the most favorable out-comes in symptomatic neonatal Ebstein’s anomaly or repair in slightly older infants have been achieved using the right ventric-ular exclusion premise. This technique, known as the “Starnes” procedure (Fig. 20-46),130 uses a fenestrated patch to close the tricuspid valve orifice coupled with systemic-to-pulmonary artery shunt. The patch must be fenestrated to allow decom-pression of the RV in instances of anatomic pulmonary atresia. Although Knott-Craig and colleagues132 have described tricus-pid valve repair for the full spectrum of neonates and infants with excellent shortand mid-term results, these results have not been reproduced in other institutions.133 The one-and-a-half ventricle repair was first described by Billingsly and cowork-ers as an attempt to achieve a more physiologic


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Surgery_Schwartz. these results have not been reproduced in other institutions.133 The one-and-a-half ventricle repair was first described by Billingsly and cowork-ers as an attempt to achieve a more physiologic “pulsatile” pul-monary circulation in patients with a hypoplastic or dysplastic RV.134 This is accomplished by diverting the superior vena caval blood directly into the pulmonary arterial system by a bidirec-tional cavopulmonary shunt while recruiting the RV to propel the inferior vena caval blood directly to the pulmonary arteries via the RVOT. Thus, the hemodynamics of the one-and-a-half ventricle repair are characterized by separate systemic and pul-monary circulations in series. The systemic circulation is fully supported by a systemic ventricle, and the pulmonary circula-tion is supported by both the bidirectional Glenn shunt and the hypoplastic (pulmonary) ventricle. Proponents of this approach report a decreased right atrial pressure and a decrease in inferior vena cava hypertension,


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Surgery_Schwartz. both the bidirectional Glenn shunt and the hypoplastic (pulmonary) ventricle. Proponents of this approach report a decreased right atrial pressure and a decrease in inferior vena cava hypertension, which is theorized to be responsible for many of the dreaded complications of the Fontan circulation, including protein-losing encephalopathy, hepatic congestion, atrial arrhythmias, and systemic ventricular failure. In addition, the maintenance of pulsatile pulmonary blood flow, as opposed to continuous laminar flow as in the Fontan circulation, may be advantageous to the pulmonary microcirculation, although it has not been proven in any studies thus far.134,135 Certain criteria, most notably an adequate tricuspid valve Z score, as well as Figure 20-45. CXR in a newborn with severe Ebsteins anomaly showing a ‘wall-to-wall’ heart.Table 20-1The Great Ormond Street Score (GOSE)GOSE Score: Area of RA + aRA/Area of RV + LA + LVGOSE ScoreRatioMortality (%)1<0.5820.5–1.0831.1–1.41004>1.5100Figure


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Surgery_Schwartz. showing a ‘wall-to-wall’ heart.Table 20-1The Great Ormond Street Score (GOSE)GOSE Score: Area of RA + aRA/Area of RV + LA + LVGOSE ScoreRatioMortality (%)1<0.5820.5–1.0831.1–1.41004>1.5100Figure 20-46. Echo appearance after a Starnes operation. Note the jet of flow across the fenestration In the patch.Brunicardi_Ch20_p0751-p0800.indd 77922/02/19 2:56 PM 780SPECIFIC CONSIDERATIONSPART IIthe absence of severe pulmonary hypertension or concomitant defects requiring intricate intracardiac repair, should be satis-fied prior to electing the one-and-a-half ventricle approach.136 Patients who do not fulfill these criteria may be approached with a two-ventricle repair and atrial fenestration or a Fontan repair.In the infant with severe Ebstein’s anomaly, initial stabili-zation with prostaglandin to maintain ductal patency, mechanical ventilation, and correction of cyanosis is mandatory. Metabolic acidosis, if present from compromised systemic perfusion, must be aggressively treated with


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Surgery_Schwartz. to maintain ductal patency, mechanical ventilation, and correction of cyanosis is mandatory. Metabolic acidosis, if present from compromised systemic perfusion, must be aggressively treated with afterload reduction. Many of these infants will improve over 1 to 2 weeks as pulmonary vascu-lar resistance falls and they are able to improve antegrade flow into the pulmonary circulation through their abnormal RV and tricuspid valve. When stabilization and medical palliation fail, surgical management remains an option, although its success depends on numerous anatomic factors (e.g., adequacy of the tricuspid valve, RV, and pulmonary outflow tract), and surgery for symptomatic neonates with Ebstein’s anomaly carries a high risk. Knott-Craig and associates reported three cases where two-ventricle repair was undertaken by subtotal closure of the ASD, extensive resection of the right atrium, and vertical plication of the atrialized chamber.132 Five-year follow-up revealed all patients to be


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Surgery_Schwartz. repair was undertaken by subtotal closure of the ASD, extensive resection of the right atrium, and vertical plication of the atrialized chamber.132 Five-year follow-up revealed all patients to be asymptomatic and in sinus rhythm without medi-cations. Recently, they have reported on their 20-year experi-ence with treating 32 such neonates with an overall mortality of 40%. Surgical management of neonates with Ebstein’s anom-aly remains challenging. For neonates with Ebstein’s anomaly and anatomical pulmonary atresia, single-ventricle palliation is associated with lower early mortality compared with two-ventricle repair.132Results. In the neonatal period, the most common postopera-tive problem, whether after a simple palliative procedure such as a BT shunt or following a more extensive procedure such as attempted exclusion of the RV, has been low cardiac out-put. Supraventricular tachycardia also has been problematic postoperatively. Complete heart block necessitating pacemaker


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Surgery_Schwartz. procedure such as attempted exclusion of the RV, has been low cardiac out-put. Supraventricular tachycardia also has been problematic postoperatively. Complete heart block necessitating pacemaker implantation should be uncommon if the techniques described to avoid suturing between the coronary sinus and the tricuspid annulus are used.There are few published reports of outcomes, due to the rarity of this defect. However, based on the natural history of this condition, which is remarkably benign for the majority of older patients, the outlook should be excellent for patients who have survived the neonatal period.127,131,132,137Transposition of the Great ArteriesAnatomy. Complete transposition is characterized by connec-tion of the atria to their appropriate ventricles with inappropriate ventriculoarterial connections. Thus, the aorta arises anteriorly from the RV, while the pulmonary artery arises posteriorly from the LV. Van Praagh and coworkers introduced the term dextro-transposition


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Surgery_Schwartz. connections. Thus, the aorta arises anteriorly from the RV, while the pulmonary artery arises posteriorly from the LV. Van Praagh and coworkers introduced the term dextro-transposition of the great arteries (D-TGA) to describe this defect, whereas levo-transposition of the great arteries (L-TGA) describes a form of corrected transposition where there is concomitant AV discordance.138,139D-TGA requires an obligatory intracardiac mixing of blood, which usually occurs at both the atrial and the ventricu-lar levels or via a patent ductus. Significant coronary anomalies occur frequently in patients with D-TGA. The most common pattern, occurring in 68% of cases, is characterized by the left main coronary artery arising from the leftward coronary sinus, giving rise to the left anterior descending and circumflex arteries. The most common variant is for the circumflex coro-nary artery to arise as a branch from the right coronary artery instead of from the left coronary


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Surgery_Schwartz. left anterior descending and circumflex arteries. The most common variant is for the circumflex coro-nary artery to arise as a branch from the right coronary artery instead of from the left coronary artery.Pathophysiology. D-TGA results in parallel pulmonary and systemic circulations, with patient survival dependent on intracardiac mixing of blood. After birth, both ventricles are relatively noncompliant, and thus, infants initially have higher pulmonary flow due to the decreased downstream resistance. This causes left atrial enlargement and a left-to-right shunt via the patent foramen ovale.Postnatally, the LV does not hypertrophy because it is not subjected to systemic afterload. The lack of normal extrauter-ine left ventricular maturation has important implications for the timing of surgical repair because the LV must be converted to the systemic ventricle and be able to function against sys-temic vascular resistance. If complete repair is done within the first few weeks of life,


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Surgery_Schwartz. repair because the LV must be converted to the systemic ventricle and be able to function against sys-temic vascular resistance. If complete repair is done within the first few weeks of life, the LV usually adapts easily to systemic resistance since it is conditioned to high intrauterine pulmonary vascular resistance. After a few weeks of life, the LV that is conditioned to the decrease in pulmonary resistance that occurs when the lungs inflate after birth may have difficulty adapting to systemic vascular resistance without preoperative preparation or postoperative support. Novel techniques of LV “preparation” using a pulmonary arterial band have been used in cases where complete repair has been delayed (Fig. 20-47A,B).Clinical Manifestations and Diagnosis. Infants with D-TGA and an intact ventricular septum are usually cyanotic at birth, with an arterial Po2 between 25 and 40 mmHg. If duc-tal patency is not maintained, deterioration will be rapid with ensuing metabolic acidosis and


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Surgery_Schwartz. ventricular septum are usually cyanotic at birth, with an arterial Po2 between 25 and 40 mmHg. If duc-tal patency is not maintained, deterioration will be rapid with ensuing metabolic acidosis and death. Conversely, those infants with a coexisting VSD may be only mildly hypoxemic and may come to medical attention after 2 to 3 weeks, when the falling pulmonary vascular resistance leads to symptoms of congestive heart failure.The ECG will reveal right ventricular hypertrophy, and the chest radiograph will reveal the classic egg-shaped con-figuration. Definitive diagnosis is made by echocardiography, which reliably demonstrates ventriculoarterial discordance and any associated lesions. Cardiac catheterization is rarely nec-essary, except in infants requiring surgery after the neonatal period, to assess the suitability of the LV to support the sys-temic circulation. Limited catheterization, however, is useful for performance of atrial septostomy in neonates with inadequate intracardiac


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Surgery_Schwartz. to assess the suitability of the LV to support the sys-temic circulation. Limited catheterization, however, is useful for performance of atrial septostomy in neonates with inadequate intracardiac mixing.Surgical Repair. Blalock and Hanlon introduced the first operative intervention for D-TGA with the creation of an atrial septectomy to enhance intracardiac mixing.140 This initial proce-dure was feasible in the pre-CPB era, but carried a high mortal-ity rate. Later, Rashkind and Causo developed a catheter-based balloon septostomy, which largely obviated the need for open septectomy.42These early palliative maneuvers, however, met with lim-ited success, and it was not until the late 1950s, when Senning and Mustard developed the first “atrial repair,” that outcomes improved. The Senning operation consisted of rerouting venous flow at the atrial level by incising and realigning the atrial sep-tum over the pulmonary veins and using the right atrial free wall to create a pulmonary venous


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Surgery_Schwartz. consisted of rerouting venous flow at the atrial level by incising and realigning the atrial sep-tum over the pulmonary veins and using the right atrial free wall to create a pulmonary venous baffle (Fig. 20-48).141Although the Mustard repair (Fig. 20-49) was similar, it made use of either autologous pericardium or synthetic material to create the interatrial baffle.142 These atrial switch procedures Brunicardi_Ch20_p0751-p0800.indd 78022/02/19 2:56 PM 781CONGENITAL HEART DISEASECHAPTER 20ABFigure 20-47. A. Echocardiographic appearance of the LV (‘*’) prior to “LV training”. B. Echocardiographic appearance of the LV (‘*’) after “LV training” achieved by the application of a tight PA band and a mBTS.ACBDFigure 20-48. The Senning operation. A. The atrial septum is cut near the tricuspid valve, creating a flap attached posteriorly between the caval veins. B. The flap of atrial septum is sutured to the anterior lip of the orifices of the left pulmonary veins, effectively separating


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Surgery_Schwartz. valve, creating a flap attached posteriorly between the caval veins. B. The flap of atrial septum is sutured to the anterior lip of the orifices of the left pulmonary veins, effectively separating the pulmonary and systemic venous channels. C. The posterior edge of the right atrial incision is sutured to the remnant of the atrial septum, diverting the systemic venous channel to the mitral valve. D. The anterior edge of the right atrial incision (lengthened by short incisions at each corner) is sutured around the cava above and below to the lateral edge of the LA incision, completing the pulmonary channel and diversion of pulmonary venous blood to the tricuspid valve area. (Reproduced with permission from Mavroudis C, Backer CL: Pediatric Cardiac Surgery, 2nd ed. St. Louis, MO: Mosby; 1994.) Figure 20-49. Angiographic appearance of a Mustard type baffle repair for dTGA.resulted in a physiologic correction, but not an anatomic one, as the systemic circulation is still based on the RV.


Surgery_Schwartz

Surgery_Schwartz. Figure 20-49. Angiographic appearance of a Mustard type baffle repair for dTGA.resulted in a physiologic correction, but not an anatomic one, as the systemic circulation is still based on the RV. Still, survival rose to 95% in most centers by using an early balloon septostomy fol-lowed by an atrial switch procedure at 3 to 8 months of age.141,142Despite the improved early survival rates, long-term problems, such as superior vena cava or pulmonary venous obstruction, baffle leak, arrhythmias, tricuspid valve regurgita-tion, and right ventricular failure, prompted the development of the arterial switch procedure by Jatene in 1975.143 The arterial switch procedure involves the division of the aorta and the pul-monary artery, posterior translocation of the aorta (LeCompte maneuver), mobilization of the coronary arteries, placement of a pantaloon-shaped pericardial patch, and proper alignment of the coronary arteries on the neoaorta (Fig. 20-50).The most important consideration is the


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Surgery_Schwartz. of the coronary arteries, placement of a pantaloon-shaped pericardial patch, and proper alignment of the coronary arteries on the neoaorta (Fig. 20-50).The most important consideration is the timing of surgical repair because arterial switch should be performed within 2 weeks after birth, before the LV loses its ability to pump against sys-temic afterload. In patients presenting later than 2 weeks, the LV can be retrained with preliminary pulmonary artery banding Brunicardi_Ch20_p0751-p0800.indd 78122/02/19 2:56 PM 782SPECIFIC CONSIDERATIONSPART IIFigure 20-50. The Arterial Switch Operation. A. The maneuver of Lecompte (positioning the pulmo-nary artery anterior to the aorta) is shown with aortic cross-clamp repositioning to retract the pulmonary artery during the neoaortic reconstruction. A and B. After the coronary patches are rotated for an optimal lie, they are sutured to the linearly incised sinuses of Valsalva at the old pulmonary artery (neoaorta) (C). (Reproduced with


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Surgery_Schwartz. A and B. After the coronary patches are rotated for an optimal lie, they are sutured to the linearly incised sinuses of Valsalva at the old pulmonary artery (neoaorta) (C). (Reproduced with permission from Mavroudis C, Backer CL: Arterial Switch. Cardiac Surgery: State of the Art Review. Vol. 5, no. 1. Philadelphia, PA: Hanley & Belfus; 1991.) Figure 20-51. Angiographic appearance of the pulmonary arteries before and after balloon dilation. The RV pressures dropped from “systemic” to “1/2 systemic” after dilation.and aortopulmonary shunt followed by definitive repair. Alter-natively, the unprepared LV can be supported following arterial switch with a mechanical assist device for a few days while it recovers ability to manage systemic pressures. Echocardiogra-phy can be used to assess left ventricular performance and guide operative planning in these circumstances.The subset of patients who present with D-TGA compli-cated by LVOT obstruction and VSD may not be suitable for an arterial


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Surgery_Schwartz. ventricular performance and guide operative planning in these circumstances.The subset of patients who present with D-TGA compli-cated by LVOT obstruction and VSD may not be suitable for an arterial switch operation. The Rastelli operation, first performed in 1968, uses placement of an intracardiac baffle to direct left ventricular blood to the aorta and an extracardiac valved conduit to establish continuity between the RV and the pulmonary artery, which has led to successful outcomes in these complex patients.144Results. For patients with D-TGA, intact ventricular septum, and VSD, the arterial switch operation provides excellent long-term results with a mortality rate of less than 5%. Operative risk is increased when unfavorable coronary anatomic configu-rations are present or when augmentation of the aortic arch is required. The most common complication is supravalvular pul-monary stenosis, occurring 10% of the time, which may require ballooning or reoperation (Fig.


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Surgery_Schwartz. or when augmentation of the aortic arch is required. The most common complication is supravalvular pul-monary stenosis, occurring 10% of the time, which may require ballooning or reoperation (Fig. 20-51).145Results of the Rastelli operation have improved substan-tially, with an early mortality rate of 5%.146 Late mortality rate results were less favorable because conduit failure requiring reoperation, pacemaker insertion, or relief of LVOT obstruc-tion was frequent.Brunicardi_Ch20_p0751-p0800.indd 78222/02/19 2:56 PM 783CONGENITAL HEART DISEASECHAPTER 20Double-Outlet Right VentricleAnatomy. Double-outlet RV (DORV) accounts for 5% of CHD and exists when both the aorta and pulmonary artery arise wholly, or in large part, from the RV (Fig. 20-52). DORV encompasses a spectrum of malformations because the incom-plete shift of the aorta toward the LV is often associated with other abnormalities of cardiac development, such as ventricular looping and infundibular-truncal spiraling.147


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Surgery_Schwartz. because the incom-plete shift of the aorta toward the LV is often associated with other abnormalities of cardiac development, such as ventricular looping and infundibular-truncal spiraling.147 The vast majority of hearts exhibiting DORV have a concomitant VSD, which varies in its size and spatial association with the great vessels. The VSD is usually nonrestrictive and represents the only out-flow for the LV; its location relative to the great vessels dictates the dominant physiology of DORV, which can be analogous to that of a large isolated VSD, tetralogy of Fallot, or D-TGA. In 1972, Lev et al148 suggested considering DORV as a spectrum of hearts that “pass imperceptibly from tetralogy with VSD with overriding aorta into double-outlet right ventricle with subaor-tic VSD.” Thus, Lev and colleagues described a classification scheme for DORV based on the “commitment” of the VSD to either or both great arteries.148 The VSD can be subaortic, dou-bly committed, noncommitted, or


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Surgery_Schwartz. Lev and colleagues described a classification scheme for DORV based on the “commitment” of the VSD to either or both great arteries.148 The VSD can be subaortic, dou-bly committed, noncommitted, or subpulmonic.The subaortic type is the most common (47%) and occurs when the VSD is located directly beneath the aortic annulus. Doubly committed VSD (4%) is present when the VSD lies beneath both the aorta and the pulmonary artery, which are usually side-by-side in this lesion. The noncommitted VSD (26%) exists when the VSD is remote from the great vessels. The subset of DORV hearts with the VSD located beneath the pulmonary valve also are classified as the Taussig–Bing syn-drome (Fig. 20-53).149 This occurs in 23% of cases of DORV with VSD, and it occurs when the aorta rotates more anteriorly, with the pulmonary artery rotated more posteriorly.150Clinical Manifestations and Diagnosis. Patients with DORV typically present with one of the following three scenar-ios: (a) those with doubly


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Surgery_Schwartz. with the pulmonary artery rotated more posteriorly.150Clinical Manifestations and Diagnosis. Patients with DORV typically present with one of the following three scenar-ios: (a) those with doubly committed or subaortic VSD present with congestive heart failure and a high propensity for pulmo-nary hypertension, much like infants with a large single VSD; (b) those with a subaortic VSD and pulmonary stenosis present with cyanosis and hypoxia, much like infants with tetralogy of Fallot; and (c) those with subpulmonic VSD present with cya-nosis, much like those with D-TGA, because streaming directs desaturated systemic venous blood to the aorta and oxygenated blood to the pulmonary artery.140 Thus, the three critical factors influencing the clinical presentation and subsequent manage-ment of infants with DORV are the size and location of the VSD, the presence or absence of important RVOT obstruc-tion, and the presence of other anomalies (especially associ-ated hypoplasia of left-sided


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Surgery_Schwartz. of infants with DORV are the size and location of the VSD, the presence or absence of important RVOT obstruc-tion, and the presence of other anomalies (especially associ-ated hypoplasia of left-sided structures sometimes seen with subpulmonary VSD).Echocardiography is the mainstay of diagnosis and can also provide valuable information regarding the feasibility of biventricular repair. Specific anatomic questions that should be resolved to assist in surgical planning in addition to those mentioned earlier include the coronary anatomy (presence of a conal branch or left anterior descending from the right coronary coursing across the conus), the presence of additional muscular VSDs remote from either great vessel, and the distance between the tricuspid and pulmonary valve. Cardiac catheterization is rarely necessary in neonates or infants, except to determine the degree of pulmonary hypertension and to determine the effects of previous palliative procedures on the pulmonary arterial


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Surgery_Schwartz. is rarely necessary in neonates or infants, except to determine the degree of pulmonary hypertension and to determine the effects of previous palliative procedures on the pulmonary arterial anatomy.Therapy. The goals of corrective surgery are to relieve pul-monary stenosis, to provide separate and unobstructed outflow pathways from each ventricle to the correct great vessel, and to achieve separation of the systemic and pulmonary circulations.Double-Outlet Right Ventricle With Noncommitted Ventricular Septal DefectThe repair of hearts with DORV and noncommitted VSD can be accomplished by constructing an intraventricular tunnel con-necting the VSD to the aorta, closing the pulmonary artery, and placing a valved extracardiac conduit from the RV to the pulmonary artery. In patients without pulmonary stenosis who have intractable congestive failure, a pulmonary artery band can be placed in the first 6 months to control pulmonary artery Figure 20-53. Angiographic appearance of the aorta in


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Surgery_Schwartz. stenosis who have intractable congestive failure, a pulmonary artery band can be placed in the first 6 months to control pulmonary artery Figure 20-53. Angiographic appearance of the aorta in a patient with Taussig-Bing anomaly. Note the hypoplastic arch (‘*’).Figure 20-52. DORV, aortomitral discontinuity (‘*’), aorta mostly arising from RV (arrow).Brunicardi_Ch20_p0751-p0800.indd 78322/02/19 2:56 PM 784SPECIFIC CONSIDERATIONSPART IIovercirculation and prevent the development of pulmonary hypertension.Infants with pulmonary stenosis can be managed with a systemic-to-pulmonary shunt followed by biventricular repair as described by Belli and colleagues in 1999, or with a modi-fied Fontan.151 There is no consensus on the timing of repair, but recent literature suggests that repair within the first 6 months is associated with better outcome. However, in cases where an extracardiac-valved conduit is necessary, it is better to delay definitive repair until the child is 2 to 3 years of


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Surgery_Schwartz. the first 6 months is associated with better outcome. However, in cases where an extracardiac-valved conduit is necessary, it is better to delay definitive repair until the child is 2 to 3 years of age because this allows placement of a larger conduit and possibly reduces the number of future obligatory conduit replacements.147Double-Outlet Right Ventricle With Subaortic or Doubly Committed Ventricular Septal Defect Without Pulmonary StenosisThis group of patients can be treated by creating an intracardiac baffle that directs blood from the LV into the aorta. Enlargement of the VSD may be necessary to allow ample room for the baf-fle; this should be done anterosuperiorly to avoid injury to the conduction system that normally lies inferoposteriorly along the border of the VSD. In addition, other important considerations in constructing the LV outflow tunnel include the prominence of the conal septum, the attachments of the tricuspid valve to the conal septum, and the distance between


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Surgery_Schwartz. other important considerations in constructing the LV outflow tunnel include the prominence of the conal septum, the attachments of the tricuspid valve to the conal septum, and the distance between the tricuspid and pulmonary valves. In some instances, unfavorable anatomy may preclude placement of an adequate intracardiac baffle, neces-sitating single ventricle repair.Double-Outlet Right Ventricle With Subaortic or Doubly Committed Ventricular Septal Defect With Pulmonary StenosisRepair of this defect is similar to the above except that concomi-tant RVOT reconstruction must be performed in addition to the intracardiac tunnel. The RVOT augmentation can be accom-plished with the placement of a transannular patch or with place-ment of an extracardiac-valved conduit when an anomalous left anterior descending artery precludes use of a patch.Taussig–Bing Syndrome Without Pulmonary StenosisThese infants are best treated with a balloon septostomy dur-ing the neonatal period to improve


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Surgery_Schwartz. anterior descending artery precludes use of a patch.Taussig–Bing Syndrome Without Pulmonary StenosisThese infants are best treated with a balloon septostomy dur-ing the neonatal period to improve mixing, followed by VSD closure baffling LV egress to the pulmonary artery and an arte-rial switch operation. The Kawashima procedure,152 in which an intraventricular tunnel is used to baffle LV egress directly to the aorta, may alternatively be used when the aorta is more posterior or when there is associated pulmonary stenosis.Taussig–Bing Syndrome With Pulmonary StenosisThis defect may be treated with a variety of techniques, depend-ing on the specific anatomic details and the expertise of the treat-ment team. A Rastelli-type repair, which involves construction of an intraventricular tunnel through the existing VSD that con-nects the LV to both great vessels, followed by division of the pulmonary artery at its origin and insertion of a valved conduit from the RV to the distal pulmonary


Surgery_Schwartz

Surgery_Schwartz. through the existing VSD that con-nects the LV to both great vessels, followed by division of the pulmonary artery at its origin and insertion of a valved conduit from the RV to the distal pulmonary artery, can be performed.153 Alternatively, a Yasui procedure, which involves baffling the VSD to the pulmonary artery and creation of a DKS anastomo-sis between the pulmonary artery and the aorta with patch aug-mentation, can be accomplished concomitant with placement of an RV pulmonary artery conduit.154Results. The results of DORV repairs are generally favor-able, especially for the tetralogy-type DORV with subaortic VSD.150,155 However, more complex types of DORV, including noncommitted VSD and Taussig–Bing type, still carry impor-tant morbidity and mortality.150,151,155 Furthermore, repeated interventions for RVOT reconstruction or staged operations for patients triaged to single-ventricle pathways pose late hazards for patients surviving initial repair. A single-institution series


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Surgery_Schwartz. interventions for RVOT reconstruction or staged operations for patients triaged to single-ventricle pathways pose late hazards for patients surviving initial repair. A single-institution series evaluated 393 patients with DORV.150 The authors found that the need for reintervention approached 37% at 15 years follow-ing repair. Arterial switch operation, as opposed to Rastelli-type repair, was associated with an increased risk of early postrepair mortality, but mitigated against the risk of late death. Patients with hypoplastic left-sided structures and a nonsubaortic VSD may fare better with a single-ventricle repair.Tetralogy of FallotAnatomy. The original description of tetralogy of Fallot (TOF) by Ettienne Louis Fallot,156 as the name implies, included four abnormalities: a large perimembranous VSD adjacent to the tri-cuspid valve; an overriding aorta; a variable degree of RVOT obstruction, which might include hypoplasia and dysplasia of the pulmonary valve as well as obstruction at


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Surgery_Schwartz. VSD adjacent to the tri-cuspid valve; an overriding aorta; a variable degree of RVOT obstruction, which might include hypoplasia and dysplasia of the pulmonary valve as well as obstruction at the subvalvar and pulmonary artery level; and right ventricular hypertrophy. More recently, the Van Praagh et al157 pointed out that TOF could be more correctly termed monology of Fallot, since the four com-ponents are explained by the malposition of the infundibular sep-tum. When the infundibular septum is displaced anteriorly and leftward, the RVOT is narrowed and its anterior displacement results in failure of fusion of the ventricular septum between the arms of the trabeculo-septo-marginalis (Fig. 20-54).The morphology of TOF is markedly heterogeneous and includes an absent pulmonary valve, concomitant AV septal defects, and pulmonary atresia with major aortopulmonary collaterals. The present discussion will focus only on the so-called classic presentation of TOF without coexisting


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Surgery_Schwartz. concomitant AV septal defects, and pulmonary atresia with major aortopulmonary collaterals. The present discussion will focus only on the so-called classic presentation of TOF without coexisting intracardiac defects.Anomalous coronary artery patterns, related to either ori-gin or distribution, have been described in TOF.158 However, the most surgically important coronary anomaly occurs when AortaMPAVSDMultilevelpulmonary stenosisRVHFigure 20-54. Tetrology of Fallot. (Used with permission from Kelly Rosso MD.)Brunicardi_Ch20_p0751-p0800.indd 78422/02/19 2:56 PM 785CONGENITAL HEART DISEASECHAPTER 20the left anterior descending artery arises as a branch of the right coronary artery. This occurs in approximately 3% of cases of TOF and may preclude placement of a transannular patch, as the left anterior descending coronary artery crosses the RVOT at varying distances from the pulmonary valve annulus.159Pathophysiology and Clinical Presentation. The initial presentation of a child


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Surgery_Schwartz. the left anterior descending coronary artery crosses the RVOT at varying distances from the pulmonary valve annulus.159Pathophysiology and Clinical Presentation. The initial presentation of a child afflicted with TOF depends on the degree of RVOT obstruction. Children with cyanosis at birth usually have severe pulmonary annular hypoplasia with concomitant hypoplasia of the peripheral pulmonary arteries. Most children, however, present with mild cyanosis at birth, which then pro-gresses as the right ventricular hypertrophy further compromises the RVOT. Cyanosis usually becomes significant within the first 6 to 12 months of life, and the child may develop characteristic “tet” spells, which are periods of extreme hypoxemia. These spells are characterized by decreased pulmonary blood flow and an increase in systemic blood flow. They can be triggered by any stimulus that decreases systemic vascular resistance, such as fever, agitation, or vigorous physical activity. Cyanotic spells


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Surgery_Schwartz. and an increase in systemic blood flow. They can be triggered by any stimulus that decreases systemic vascular resistance, such as fever, agitation, or vigorous physical activity. Cyanotic spells increase in severity and frequency as the child grows, and older patients with uncorrected TOF may often squat, which increases peripheral vascular resistance and relieves the cyanosis.Evaluation in the older patient with TOF may demonstrate clubbing, polycythemia, hemoptysis, or brain abscesses. Chest radiography will demonstrate a boot-shaped heart (Fig. 20-55), and EKG will show the normal pattern of right ventricular hypertrophy. Echocardiography confirms the diagnosis because it demonstrates the position and nature of the VSD, defines the character of the RVOT obstruction, and often visualizes the branch pulmonary arteries and the proximal coronary arteries. Cardiac catheterization is rarely necessary and is actually risky in TOF since it can create spasm of the RVOT muscle and result in


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Surgery_Schwartz. the branch pulmonary arteries and the proximal coronary arteries. Cardiac catheterization is rarely necessary and is actually risky in TOF since it can create spasm of the RVOT muscle and result in a hypercyanotic episode (tet spell). Occasionally, aortogra-phy (Fig. 20-56) is necessary to delineate the coronary artery anatomy.Treatment. John Deanfield160 stated “…long follow-up inevi-tably means surgery in an earlier era: More recent surgery, at a younger age, with better preoperative, operative, and post-operative care, will improve long-term results. Data from the former (earlier) era will be overly pessimistic.” This statement is particularly pertinent as surgical correction of TOF has evolved from a staged approach of antecedent palliation in infancy fol-lowed by intracardiac repair to primary repair during the first few months of life without prior palliative surgery.However, systemic-to-pulmonary shunts, generally an MBTS, may still be preferred with an unstable neonate younger