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Surgery_Schwartz. ring of the prosthetic valve, taking care to avoid damage to the coronary ostia, the conduction system, and the MV appara-tus. The annular sutures may be placed from below the annulus, seating the valve supra-annularly, or from above the annulus for intra-annular placement (Fig. 21-11).The major components to increased operative risk associ-ated with surgical AVR include age, body surface area, diabetes, renal failure, hypertension, chronic lung disease, peripheral vas-cular disease, neurologic events, infectious endocarditis, previ-ous cardiac surgery, myocardial infarction, cardiogenic shock, NYHA functional status, and pulmonary hypertension. For most patients, the risk of operative mortality associated with AVR is 1% to 5%, and 5-year survival has been reported to be >80%, even in patients >70 years of age.138-161 The choice of valve is dependent on many patient-related factors, and it is accompa-nied by the attendant postoperative risks of decreased durability and thromboembolic


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Surgery_Schwartz. >70 years of age.138-161 The choice of valve is dependent on many patient-related factors, and it is accompa-nied by the attendant postoperative risks of decreased durability and thromboembolic vs. hemorrhagic complications for biologi-cal and mechanical valves, respectively.Aortic Valve Repair. Although aortic valve replacement is performed more commonly, AV repair may be recommended at centers of excellence.96For patients with aortoannular ectasia, AI is due to annular dilatation and distortion of the sinotubular junction. For these Figure 21-11. Aortic valve replacement. The stented porcine bio-prosthesis as viewed through an aortotomy.patients, competence of the aortic valve can be achieved by functionally repairing the annulus in a method analogous to homograft implantation. The aneurysmal portion of the aor-tic root is excised, and the aortic valve is reimplanted inside a tubular Dacron graft, with concomitant reimplantation of the coronary arteries. Alternatively, the


Surgery_Schwartz

Surgery_Schwartz. The aneurysmal portion of the aor-tic root is excised, and the aortic valve is reimplanted inside a tubular Dacron graft, with concomitant reimplantation of the coronary arteries. Alternatively, the aneurysmal tissue and supravalvular tissue can be excised in their entirety, with subse-quent implantation of the Dacron graft onto the superior aspect of the annulus and reimplantation of the coronary arteries.Valve-sparing root replacement for root and annular sta-bilization in patients with AI due to aortoannular ectasia has led to a more durable outcome than is seen with subcommis-sural annuloplasty or leaflet-related procedures alone. One study demonstrated equivalent overall survival between patients undergoing subcommissural annuloplasty or aortic valve repair without annuloplasty and patients undergoing valve-sparing root replacement at 6 years.162 However, patients who under-went valve-sparing root replacement had higher freedom from reoperation and aortic insufficiency >2+ (100%


Surgery_Schwartz

Surgery_Schwartz. undergoing valve-sparing root replacement at 6 years.162 However, patients who under-went valve-sparing root replacement had higher freedom from reoperation and aortic insufficiency >2+ (100% vs. 90%, P = 0.03; and 100% vs. 77%, P = 0.002, respectively) at midterm follow-up.162For patients with AI associated with redundant leaflet tis-sue, aortic valve repair may be accomplished with free margin plication or resuspension of the valve cusps, with or without triangular resection of the redundant segment. Excision of the diseased portion of the involved valve cusp improves symme-try of the valve leaflets, and annular plication of one or both commissures helps to ensure adequate coaptation. Generally, the free margins of the excised leaflets are reapproximated pri-marily, but in the absence of adequate cusp tissue, a triangular autologous or bovine pericardial patch may be used for cusp restoration.AV cusp repair with a free margin plication or resuspen-sion technique has demonstrated


Surgery_Schwartz

Surgery_Schwartz. of adequate cusp tissue, a triangular autologous or bovine pericardial patch may be used for cusp restoration.AV cusp repair with a free margin plication or resuspen-sion technique has demonstrated encouraging results in expert centers, both in patients with tricuspid and bicuspid aortic valves. Freedom from AV reoperation in patients with a tricus-pid AV has been reported to be 89% to 92% at 10 years, with a freedom from recurrent AI >2+ of 80% to 86% at the same time point. In patients with bicuspid aortic valves, who gener-ally represent a younger cohort of patients, 10-year survival has been reported at 94% following AV repair, with a freedom from AV reoperation of 81% at the same time point.163Ross Procedure. As mentioned previously, the Ross procedure involves replacing the diseased AV with the patient’s native pulmonary valve as an autograft, which is in turn replaced with a homograft in the pulmonic position.112 The autograft may be implanted in the aortic position directly


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Surgery_Schwartz. AV with the patient’s native pulmonary valve as an autograft, which is in turn replaced with a homograft in the pulmonic position.112 The autograft may be implanted in the aortic position directly with resuspension of the valve commissures, or in association with a root replacement, which requires reimplantation of the coronary ostia.The cylinder root replacement technique is most reproduc-ible and involves transecting the native aorta approximately 5 mm above the sinotubular ridge, with subsequent excision of the aortic valve leaflets and supra-annular tissue. The main pulmonary artery is transected at the bifurcation, and the right ventricular outflow tract is incised, allowing the pulmonary valve and artery to be removed en bloc from the outflow tract. The annulus of the pulmonary autograft is sewn to the native aortic annulus with continuous or interrupted sutures, and the coronary ostia are reimplanted into the pulmonary artery graft. The pulmonary valve and right ventricular


Surgery_Schwartz

Surgery_Schwartz. is sewn to the native aortic annulus with continuous or interrupted sutures, and the coronary ostia are reimplanted into the pulmonary artery graft. The pulmonary valve and right ventricular outflow tract are subsequently reconstructed using an aortic homograft.Brunicardi_Ch21_p0801-p0852.indd 82801/03/19 5:32 PM 829ACQUIRED HEART DISEASECHAPTER 21The primary benefit of the Ross procedure compared to traditional AV surgery is a low risk of thromboembolism with-out the need for systemic anticoagulation. Although patients undergoing the Ross procedure are generally younger, periop-erative mortality has been reported to be as low as 2.5% in this group, with an overall survival of 90% at 18-year follow-up.164 However, the long-term durability of the procedure is somewhat questionable. Although Ross reported a freedom from autograft replacement of 75% at 20 years, other groups have reported freedom from autograft reoperation and allograft reinterven-tion of 51% and 82%, respectively,


Surgery_Schwartz

Surgery_Schwartz. Ross reported a freedom from autograft replacement of 75% at 20 years, other groups have reported freedom from autograft reoperation and allograft reinterven-tion of 51% and 82%, respectively, at 18-year follow-up.164,165 Progressive aortic insufficiency has been described as a cause of late failure in these patients, as well as calcification of the pulmonary homograft and pulmonary stenosis.Transcatheter Aortic Valve Replacement. Transcatheter aortic valve replacement (TAVR) has proven beneficial for the treatment of AS in patients who are either moderate or high-risk candidates for conventional surgery. TAVR is now indicated for patients with severe AS with a STS score predicted risk of mortality of greater than or equal to 3%.152 Clinical trials in the low-risk population are currently underway.There are two types of transcatheter valves that are approved for commercial use: a balloon-expandable valve (Edwards) and a self-expandable valve (CoreValve). A trans-catheter valve may be


Surgery_Schwartz

Surgery_Schwartz. underway.There are two types of transcatheter valves that are approved for commercial use: a balloon-expandable valve (Edwards) and a self-expandable valve (CoreValve). A trans-catheter valve may be inserted via the femoral artery, the left subclavian artery, the ascending thoracic aorta via an upper mini-sternotomy, or LV apex via a small left anterior thoracot-omy. By far the most common route is transfemoral, making up the majority of TAVR in most centers. The principle of valves placed via these routes are to place the aortic prosthesis inside the patient’s native aortic valve. Rigorous preoperative plan-ning is needed to ensure adequate sizing of the valve as well as placement to ensure there is no risk of coronary occlusion or malalignment of the valve.A series of large, multicenter clinical trials have been per-formed investigating the role and safety of TAVR in patients with severe aortic stenosis requiring surgical treatment. The PARTNER I trial looked at mortality rate as


Surgery_Schwartz

Surgery_Schwartz. clinical trials have been per-formed investigating the role and safety of TAVR in patients with severe aortic stenosis requiring surgical treatment. The PARTNER I trial looked at mortality rate as the primary endpoint in patients with severe aortic stenosis who were not suitable can-didates for surgery (high-risk patients).166 TAVR, as compared with standard surgical treatment (SAVR), significantly reduced the rates of death from any cause (30.7% vs. 50.7%, at 1 year, P <0.001), the composite endpoint of death from any cause or repeat hospitalization (42.5% vs. 71.6%, P <0.001), and cardiac symptoms (25.2% vs. 58.0%, P <0.001), despite the higher inci-dence of major strokes (5.0% vs. 1.1%, P = 0.06) and major vas-cular events (16.2% vs. 1.1%, P <0.001).166 In the PARTNER II trial, 2032 intermediate-risk patients with severe aortic stenosis were randomly assigned to undergo either TAVR or SAVR.167 It was found that in intermediate-risk patients, TAVR was simi-lar to SAVR with respect


Surgery_Schwartz

Surgery_Schwartz. patients with severe aortic stenosis were randomly assigned to undergo either TAVR or SAVR.167 It was found that in intermediate-risk patients, TAVR was simi-lar to SAVR with respect to the primary end point of death or disabling stroke (P = 0.001 for noninferiority). TAVR resulted in larger aortic valve areas than did surgery and also resulted in lower rates of acute kidney injury, severe bleeding, and new-onset atrial fibrillation; surgery resulted in fewer major vascu-lar complications and less paravalvular aortic regurgitation.167 Similarly, the Surgical or Transcatheter Aortic-Valve Replace-ment in Intermediate-Risk patients trial (SURTAVI) evaluated the clinical outcomes in intermediate-risk patients with severe, symptomatic aortic stenosis in a randomized trial comparing TAVR (performed with the use of a self-expanding prosthesis) 5with surgical aortic-valve replacement.168 TAVR was found to be a noninferior (i.e., similar composite endpoint of death from any cause or disabling


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Surgery_Schwartz. with the use of a self-expanding prosthesis) 5with surgical aortic-valve replacement.168 TAVR was found to be a noninferior (i.e., similar composite endpoint of death from any cause or disabling stroke at 24 months) alternative to surgery in patients with severe aortic stenosis at intermediate surgical risk, with a different pattern of adverse events associ-ated with each procedure. Surgery was associated with higher rates of acute kidney injury, atrial fibrillation, and transfusion requirements, whereas TAVR had higher rates of residual aor-tic regurgitation and need for pacemaker implantation.168 The PARTNER III trial, currently under investigation, is designed to establish the safety and effectiveness of TAVR in patients with severe, calcific aortic stenosis who are at low operative risk for standard surgical aortic valve replacement (SAVR). Ongoing trials will continue to define the roles for SAVR and TAVR in the future.TRICUSPID VALVE DISEASETricuspid Stenosis and


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Surgery_Schwartz. operative risk for standard surgical aortic valve replacement (SAVR). Ongoing trials will continue to define the roles for SAVR and TAVR in the future.TRICUSPID VALVE DISEASETricuspid Stenosis and InsufficiencyEtiology. Acquired tricuspid valve (TV) disease can be clas-sified as either organic or functional and affects approximately 0.8% of the general population.169 Tricuspid stenosis (TS) is almost always a result of rheumatic heart disease or rarely endo-carditis. In the case of rheumatic disease, tricuspid stenosis with or without associated insufficiency is invariably associated with mitral valve disease. Other less common causes of obstruction to right atrial emptying include congenital tricuspid atresia, right atrial tumors, and endomyocardial fibrosis.Tricuspid insufficiency (TR), on the other hand, is most often a functional disease caused by secondary dilation of the tricuspid annulus due to pulmonary hypertension and/or right heart failure. This is most commonly caused by


Surgery_Schwartz

Surgery_Schwartz. on the other hand, is most often a functional disease caused by secondary dilation of the tricuspid annulus due to pulmonary hypertension and/or right heart failure. This is most commonly caused by MV disease. Conditions such as right ventricular infarction and pulmonic stenosis can also lead to increased right ventricular pressures and functional TR. The less common causes of organic TR, with or without associated stenosis, include endocarditis, carcinoid syndrome, radiation therapy, trauma such as repeated endomyo-cardial biopsy, and Marfan syndrome.Pathology. The changes associated with TS closely resemble those associated with MS, including fusion of the commissures.169 In the case of rheumatic disease, mixed TS and TR may result from fusion and shortening of the chordae tendineae, and fusion of the commissures, causing retraction of the valve leaflets. The right atrium is frequently dilated and thickened in chronic TS, and chronic obstruction to right ventricular filling often


Surgery_Schwartz

Surgery_Schwartz. and fusion of the commissures, causing retraction of the valve leaflets. The right atrium is frequently dilated and thickened in chronic TS, and chronic obstruction to right ventricular filling often produces signs of systemic venous congestion such as hepatomegaly and splenomegaly.2In most cases of TR, dilation and deformation of the tri-cuspid annulus is the most prominent feature; the valve leaflets oftentimes appear stretched but are otherwise pliable and nor-mal in appearance.2 When TR is caused by carcinoid syndrome, white fibrous carcinoid plaques are found on the ventricular sur-faces of the TV, causing the cusps to adhere to the underlying right ventricular wall and stenting the valve open.2Pathophysiology. The basic pathophysiologic abnormality of both TS and severe TR is elevated right atrial pressure, produc-ing systemic congestion and right heart failure. Severe TS is marked by a valve area <1.0 cm2, and severe TR is defined as a vena contracta width of >0.7 cm in


Surgery_Schwartz

Surgery_Schwartz. elevated right atrial pressure, produc-ing systemic congestion and right heart failure. Severe TS is marked by a valve area <1.0 cm2, and severe TR is defined as a vena contracta width of >0.7 cm in combination with sys-tolic flow reversal in the hepatic veins.98 However, in patients with TS, a diastolic pressure gradient of only 5 mmHg, or a TV Brunicardi_Ch21_p0801-p0852.indd 82901/03/19 5:32 PM 830SPECIFIC CONSIDERATIONSPART IITable 21-12Data from ACC/AHA guidelines for TV surgery in specific clinical contextsCLINICAL SETTINGCLASS OF RECOMMENDATIONLEVEL OF EVIDENCESurgery for Tricuspid Valve Disease• TVr for severe TI in patients with MV disease requiring MV surgeryIB• TVR or annuloplasty for severe symptomatic primary TIIIaC• TVR for severe TI secondary to diseased/abnormal TV leaflets not amenable to annuloplasty or TVrIIaC• Annuloplasty for less than severe TI in patients undergoing MV surgery in the setting of1) Pulmonary hypertension2) Tricuspid annular dilatationIIbC• TVR


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Surgery_Schwartz. not amenable to annuloplasty or TVrIIaC• Annuloplasty for less than severe TI in patients undergoing MV surgery in the setting of1) Pulmonary hypertension2) Tricuspid annular dilatationIIbC• TVR or annuloplasty is not indicated in asymptomatic patients with TI, a normal MV, and a PASP <60 mmHgIII – HarmC• TVR or annuloplasty is not indicated in patients with mild primary TIIII – HarmCMV = mitral valve; PASP = pulmonary artery systolic pressure; TI = tricuspid insufficiency; TV = tricuspid valve; TVr = tricuspid valve repair; TVR = tricuspid valve replacement.orifice <1.5 cm2, is frequently enough to cause jugular venous distention, organomegaly, and peripheral edema. In severe cases, cardiac output is compromised, especially during exercise when the fixed obstruction prevents an increase in forward flow. Patients with severe insufficiency and pulmonary hypertension experience similar hemodynamic derangements.Clinical Manifestations. Patients with TS and severe TR develop symptoms of


Surgery_Schwartz

Surgery_Schwartz. in forward flow. Patients with severe insufficiency and pulmonary hypertension experience similar hemodynamic derangements.Clinical Manifestations. Patients with TS and severe TR develop symptoms of right heart failure associated with chroni-cally elevated right atrial pressures.2 The classic clinical signs and symptoms of TS and severe TR are jugular venous disten-tion, hepatomegaly, splenomegaly, ascites, and lower extremity edema. Uncomfortable fluttering in the neck has been reported in patients with TV disease, and sensations of throbbing in the eyeballs and pulsatile varicose veins have been reported to occur, especially in patients with severe TR.The low cardiac output syndrome occasionally associated with TS and severe TR can cause fatigue, weakness, and exer-cise intolerance in these patients. In the absence of pulmonary hypertension, dyspnea is not a prominent feature of tricuspid disease. The auscultatory findings associated with TS include a presystolic and middiastolic


Surgery_Schwartz

Surgery_Schwartz. these patients. In the absence of pulmonary hypertension, dyspnea is not a prominent feature of tricuspid disease. The auscultatory findings associated with TS include a presystolic and middiastolic murmur characterized by a tri-cuspid opening snap that increases on inspiration. The lower left parasternal murmur of TR may be holosystolic or less than holosystolic, depending on the degree of regurgitation, may be associated with a middiastolic murmur in severe cases, and may increase on inspiration.Diagnostic Studies. In patients with TV disease, chest X-ray frequently demonstrates enlargement of the right atrium and ventricle. Patients with TS demonstrate an exaggerated a wave and a diminished rate of y descent in the jugular venous pulse, while patients with TR have abnormal systolic c and v waves.2 TTE examination should be performed in patients with TV disease in order to characterize the structure and motion of the TV, the size of the tricuspid annulus, and other cardiac


Surgery_Schwartz

Surgery_Schwartz. c and v waves.2 TTE examination should be performed in patients with TV disease in order to characterize the structure and motion of the TV, the size of the tricuspid annulus, and other cardiac abnormalities that may affect TV function.98 In patients with a pulmonary artery systolic pressure >55 mmHg, TI commonly occurs in the setting of structurally normal valves; however, structural derangement of the TV apparatus is frequently present if TR is documented with a pulmonary artery systolic pressure <40 mmHg. Doppler TTE allows estimations of the severity of TR, the right ventricular systolic pressure, and the TV diastolic gradient.Indications for Operation. As an isolated lesion, mild or moderate TV disease does not require surgical correction. How-ever, patients with severe TV disease should be considered for surgical intervention, especially in the setting of right ventricu-lar enlargement and impaired systolic function, as this improves life expectancy and the development of


Surgery_Schwartz

Surgery_Schwartz. should be considered for surgical intervention, especially in the setting of right ventricu-lar enlargement and impaired systolic function, as this improves life expectancy and the development of sequelae such as heart failure and atrial fibrillation.169 Depending on the patient’s clini-cal status and the cause of TV dysfunction, TV repair and TV replacement be variably recommended for the treatment of TV dysfunction (Table 21-12).98 In patients with TR, the valve can usually be repaired with modern techniques.Operative Techniques and Results. The TV can be approached through a median sternotomy, a right thoracotomy, or port-based techniques. Surgery is performed with the assis-tance of cardiopulmonary bypass and, though TV surgery is usually performed on the beating heart, a brief period of car-dioplegic arrest may be rarely needed to allow for complete inspection of the interatrial septum and to close any defects that may be present.TV repair may include a suture or ring


Surgery_Schwartz

Surgery_Schwartz. period of car-dioplegic arrest may be rarely needed to allow for complete inspection of the interatrial septum and to close any defects that may be present.TV repair may include a suture or ring annuloplasty as well as valvuloplasty, and multiple methods have been described.169 Historically, bicuspidization of the TV was accomplished by a figure-of-eight suture plication of the annulus of the posterior leaflet; however, this technique has been essentially replaced by suture or ring annuloplasty. Suture annuloplasty is gener-ally performed by placing pledgeted sutures along the base of the anterior and posterior leaflets, partially encircling the annulus. Ring annuloplasty can be accomplished by suturing the TV annulus to a variety of rigid or semirigid annuloplasty rings, which generally have an opening at the level of the anterosep-tal commissure to avoid passing the anchoring sutures near to the conduction system. Most surgeons favor ring over suture annuloplasty. In severe annular


Surgery_Schwartz

Surgery_Schwartz. have an opening at the level of the anterosep-tal commissure to avoid passing the anchoring sutures near to the conduction system. Most surgeons favor ring over suture annuloplasty. In severe annular dilatation, augmentation of the anterior leaflet with autologous pericardium has been used with some success. Tricuspid valvuloplasty is infrequently performed and may include commissurotomy, triangular leaflet resection, Brunicardi_Ch21_p0801-p0852.indd 83001/03/19 5:32 PM 831ACQUIRED HEART DISEASECHAPTER 21primary perforation repair, and traditional leaflet repair tech-niques such as chordal transfer, shortening, and replacement, papillary muscle plication, tricuspid leaflet augmentation, and the edge-to-edge repair technique used in MV prolapse.For patients with functional TV disease, TV repair is gen-erally preferred to replacement due to favorable results without the associated risks of thrombosis and the need for anticoagu-lation. In the setting of concomitant mitral valve


Surgery_Schwartz

Surgery_Schwartz. TV repair is gen-erally preferred to replacement due to favorable results without the associated risks of thrombosis and the need for anticoagu-lation. In the setting of concomitant mitral valve surgery, TV repair has not been associated with additional perioperative complications, and 5-year freedom from reoperation has been impressive at 98%. However, a subgroup of patients report late failure following TV repair, and this may be worse following suture annuloplasty compared with ring annuloplasty.117Prosthetic valve replacement may be necessary due to extensive leaflet destruction, as may be seen in patients with endocarditis, or marked annular dilatation not amenable to repair. In some cases, the valve prosthesis may be anchored directly to the leaflet tissue instead of the valve annulus, reduc-ing the risk of injury to the conduction system.169 If this tech-nique is used, it should be confirmed that the residual tissue does not interfere with the movement of the prosthetic


Surgery_Schwartz

Surgery_Schwartz. annulus, reduc-ing the risk of injury to the conduction system.169 If this tech-nique is used, it should be confirmed that the residual tissue does not interfere with the movement of the prosthetic leaflets after implantation. Pledgeted sutures should be used and may be placed on the ventricular or atrial side of the annulus.Outcomes data following TV replacement are difficult to interpret, as most reports are in patients with previous TV surgery and/or signs of severe right heart failure. Operative mortality has been >20% in some studies.169 One study of 87 patients undergoing TV replacement between 1994 and 2007 showed an in-hospital mortality of only 1.4%. The choice of prosthetic valve is also somewhat controversial. Though bio-prosthetic valves are more durable in the tricuspid than mitral or aortic positions, valve degeneration is an important cause of bioprosthetic valve dysfunction at reoperation. The ability to replace a degenerated tricuspid valve bioprosthesis with a


Surgery_Schwartz

Surgery_Schwartz. than mitral or aortic positions, valve degeneration is an important cause of bioprosthetic valve dysfunction at reoperation. The ability to replace a degenerated tricuspid valve bioprosthesis with a trans-catheter valve has led some surgeons to favor biological valves in this position. This is particularly true since the increased risk of valve thrombosis seen with mechanical valves mandates rig-orous systemic anticoagulation. Even with these precautions, mechanical tricuspid valves are associated with an increased risk of hemorrhagic and thrombotic complications. The choice of valve is usually decided on a case-by-case basis, and late out-comes have been similar with biological and mechanical valves in this position. In general, TV replacement may be a reasonable choice in select patients, though more data are needed regarding long-term outcomes in the modern era.Multivalve DiseasePathology involving multiple valves is relatively common and may result from diseases such as rheumatic


Surgery_Schwartz

Surgery_Schwartz. though more data are needed regarding long-term outcomes in the modern era.Multivalve DiseasePathology involving multiple valves is relatively common and may result from diseases such as rheumatic fever, calcific dis-ease, Marfan syndrome, and other connective tissue disorders. However, multivalve disease may also be caused by secondary valvular dysfunction due to a distal valvular lesion, as in the case of myxomatous degeneration of the mitral valve, resulting in pulmonary hypertension, dilation of the tricuspid annulus, and functional TR. If the primary pathology is corrected early in the disease course, these secondary functional changes may resolve without the need for intervention.In patients with multivalve disease, the clinical manifesta-tions may be dependent on the severity of each individual valve lesion, but this is not always the case.2 In patients with con-comitant mitral and tricuspid dysfunction, the prominent symp-toms of dyspnea, paroxysmal nocturnal dyspnea, and


Surgery_Schwartz

Surgery_Schwartz. each individual valve lesion, but this is not always the case.2 In patients with con-comitant mitral and tricuspid dysfunction, the prominent symp-toms of dyspnea, paroxysmal nocturnal dyspnea, and orthopnea commonly associated with MV dysfunction are sometimes diminished by associated TV dysfunction. Symptoms of multi-valve disease are most commonly masked when valvular abnor-malities are of approximately equal severity, highlighting the importance of careful examination of each valve both preopera-tively and in the operating room.Surgery for multivalve disease is associated with a higher perioperative mortality than single-valve procedures, and this risk is exacerbated by factors such as pulmonary artery hyper-tension, age, triple-valve procedures, concomitant coronary artery bypass grafting, previous heart surgery, renal insuffi-ciency, and diabetes.170 Failing to recognize significant con-comitant valvular dysfunction at the time of surgery is also associated with higher


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Surgery_Schwartz. grafting, previous heart surgery, renal insuffi-ciency, and diabetes.170 Failing to recognize significant con-comitant valvular dysfunction at the time of surgery is also associated with higher perioperative mortality. For this reason, patients suspected of having multivalve involvement should undergo full preoperative Doppler TTE or TEE evaluation and heart catheterization.98 In selected patients, procedures correcting multivalve disease demonstrate significant clinical improvement in symptoms and quality of life, as well as accept-able mortality and survival rates.170SURGICAL THERAPY FOR THE FAILING HEARTEpidemiology of Heart FailureHeart failure affects approximately 5 million patients in the United States, with >550,000 new cases diagnosed annually.171 The disorder is the primary reason for 12 to 15 million office visits and >1 million hospitalizations each year. Overall 1-year mortality is estimated to be around 25%, but this can increase to as high as 75% for patients with more


Surgery_Schwartz

Surgery_Schwartz. for 12 to 15 million office visits and >1 million hospitalizations each year. Overall 1-year mortality is estimated to be around 25%, but this can increase to as high as 75% for patients with more advanced heart failure (NYHA class IV).172 While heart transplantation remains the gold standard for the treatment of end stage disease, an increas-ing number of patients deteriorate while on the waiting list, and up to 30% die before transplantation.173 The total direct and indirect costs associated with the treatment of heart failure are estimated to be $32 billion, and this is projected to increase to $70 billion by 2030.174 Advances in the surgical management of heart failure over the two decades have pushed surgery for CHF into the mainstream. As a result, there is an increasing number of patients with lateor end-stage disease who are being consid-ered for surgical therapies.Etiology and PathophysiologyHeart failure can be classified as acute or chronic, genetic or acquired, left-sided


Surgery_Schwartz

Surgery_Schwartz. with lateor end-stage disease who are being consid-ered for surgical therapies.Etiology and PathophysiologyHeart failure can be classified as acute or chronic, genetic or acquired, left-sided and/or right-sided, and systolic and/or diastolic dysfunction. The underlying causes and treatments for each of these vary considerably. In the Framingham Heart Study, coronary artery disease accounted for 67% of heart fail-ure cases, valvular heart disease accounted for 10%, and 20% of cases were attributable to primary myocardial diseases, of which dilated cardiomyopathy predominated.175 In all cases, heart failure is a progressive disorder that through complex mechanisms of ventricular remodeling, altered hemodynamics, neurohumoral activation, cytokine overexpression, and vascu-lar and endothelial dysfunction either disrupts the ability of the myocardium to generate force or results in a loss of function-ing cardiac myocytes, thereby preventing normal myocardial contraction.CABG for Ischemic


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Surgery_Schwartz. dysfunction either disrupts the ability of the myocardium to generate force or results in a loss of function-ing cardiac myocytes, thereby preventing normal myocardial contraction.CABG for Ischemic CardiomyopathySurgical coronary revascularization is among the most com-monly performed procedures for CHF. CABG is beneficial as it protects from further myocardial infarction and/or malignant Brunicardi_Ch21_p0801-p0852.indd 83101/03/19 5:32 PM 832SPECIFIC CONSIDERATIONSPART IIventricular arrhythmias. It is most successful when treating hibernating as opposed to infarcted myocardium.While the majority of evidence supporting CABG for patients with ischemic cardiomyopathy comes from nonran-domized, retrospective studies, the prospective, randomized, multicenter international Surgical Treatment of Ischemic Heart Failure (STICH) trial compared CABG with medical therapy to medical therapy alone. Entry criteria included an EF ≤35% with CAD and anatomy suitable for CABG. No significant


Surgery_Schwartz

Surgery_Schwartz. of Ischemic Heart Failure (STICH) trial compared CABG with medical therapy to medical therapy alone. Entry criteria included an EF ≤35% with CAD and anatomy suitable for CABG. No significant difference was seen in overall mortality by study completion, but patients who underwent CABG did have fewer deaths or hospitalizations from cardiovascular causes (58% vs. 68%, P <0.001).176,177Myocardial viability testing has been shown by multiple studies to be pivotal in identifying patients that will have improved outcomes following CABG for ischemic cardiomyopathy.178,179 A meta-analysis performed by Allman et al demonstrated an 80% reduction in mortality in patients who underwent revas-cularization with viable myocardium compared to patients who received medical therapy alone (3.2% vs. 16%, P <0.0001). Most importantly, in this analysis, CABG had no benefit over medical therapy for patients without viable myocardium. A more recent study by Gerber et al prospectively compared CABG and medical


Surgery_Schwartz

Surgery_Schwartz. Most importantly, in this analysis, CABG had no benefit over medical therapy for patients without viable myocardium. A more recent study by Gerber et al prospectively compared CABG and medical therapy to medical therapy alone in 114 patients with CAD and low EF (24% ± 8%) who underwent viability testing using delayed-enhancement cardiac MRI.180 This study demon-strated worse 3-year survival in medically treated patients with dysfunctional but viable myocardium than in medically treated patients with nonviable myocardium (48% vs. 77%, P = 0.02). This corresponded with a 4.56 times increased hazard of death when medical treatment was selected over full revasculariza-tion. In contrast, survival after CABG was not significantly different whether myocardium was viable or not (88% vs. 71%, P = NS). These studies underscore both the importance of viable myocardium as well as the adverse consequences of not offering a patient with viability surgical intervention.Patients with ischemic


Surgery_Schwartz

Surgery_Schwartz. P = NS). These studies underscore both the importance of viable myocardium as well as the adverse consequences of not offering a patient with viability surgical intervention.Patients with ischemic cardiomyopathy are a heterogeneous group, and, as with any surgery, appropriate patient selection is central to success. In one retrospective study of 96 patients with ischemic cardiomyopathy (EF ≤25%), age and poor distal vessel quality were predictors of poor outcomes.181 Mortality in patients with poor vessel quality was 100%, compared with 90% when vessel quality was fair and 10% when it was good. Therefore, poor vessel quality should be considered a contraindication to surgical revascularization even in the presence of angina.LV size and LV dyssynchrony are also risk factors for adverse shortand intermediate-term outcomes. A LV end-diastolic dimension of >100 mL/m2 is associated with a signifi-cantly reduced 5-year survival following CABG (85% vs. 53%, P <0.05), as well as worse 5-year


Surgery_Schwartz

Surgery_Schwartz. intermediate-term outcomes. A LV end-diastolic dimension of >100 mL/m2 is associated with a signifi-cantly reduced 5-year survival following CABG (85% vs. 53%, P <0.05), as well as worse 5-year freedom from recurrent CHF (85% vs. 31%).182 Moreover, LV dyssynchrony has been shown to have a significant impact on mortality in patients undergo-ing moderateto high-risk revascularization and may compound risk in patients with nonviable myocardium.183 In patients with severe preoperative LV dyssynchrony, the 30-day mortality was 27% vs. 3% in patients without significant dyssynchrony (P <0.001). Similar differences were seen with the presence of postoperative LV dyssynchrony, and outcomes were worse when patients also had fewer segments of viable myocardium.Secondary Mitral RegurgitationSecondary mitral regurgitation describes MR that results from damage to the left ventricle as a result of either ischemia or dilated cardiomyopathy rather than from a problem with the valve itself.184


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Surgery_Schwartz. mitral regurgitation describes MR that results from damage to the left ventricle as a result of either ischemia or dilated cardiomyopathy rather than from a problem with the valve itself.184 Ischemic MR (IMR) typically results from sys-tolic restriction of the mitral leaflets due to tethering of the subvalvular apparatus. This occurs mainly from regional wall motion abnormalities in areas of the LV adjacent to papillary muscle attachments. Alterations in the size and shape of the mitral annulus and posterior displacement of the posteromedial papillary muscle, which occurs primarily after an inferoposterior MI, may also contribute. Additionally, functional MR (FMR) is caused by LV dilatation and increased sphericity, which displace the papillary muscles apically and radially, creating lateral forces on the valve that lead to increased retraction of the mitral leaflets by the chordae tendineae. LV dyssynchrony may also contribute to FMR through poor coordination of the contraction of


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Surgery_Schwartz. forces on the valve that lead to increased retraction of the mitral leaflets by the chordae tendineae. LV dyssynchrony may also contribute to FMR through poor coordination of the contraction of the septum and lateral walls, producing MR that may vary in intensity during the cardiac cycle. Functional MR is usually referred to as a Carpentier class I/IIIb lesion due to the presence of both annular dilatation (Carpentier type I) and systolic restriction of the mitral leaflets due to LV dysfunction (Carpentier type IIIb). Ultimately, increased regurgitation leads to increased preload, LV wall tension, and LV work load, all of which contribute to progressive dysfunction of the LV and worsening heart failure.Several observational and population-based studies have demonstrated a significant impact of secondary MR on long-term survival. Following MI, the 5-year survival rate dropped significantly from 61% in patients who did not have MR to 47% and 29% in patients with mild and moderate to


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Surgery_Schwartz. of secondary MR on long-term survival. Following MI, the 5-year survival rate dropped significantly from 61% in patients who did not have MR to 47% and 29% in patients with mild and moderate to severe MR, respectively.185 Similarly, in a series of 2057 patients with symptomatic heart failure and an LVEF <40%, the 5-year sur-vival rate for patients without MR was 54%, and it decreased to 40% in patients with moderate to severe secondary MR.186 Moreover, medical therapy and PCI have not reduced the impact of IMR on late mortality.187Although specific recommendations to intervene for secondary MR are controversial and have not been rigorously defined, guidelines are available (Table 21-13).96,188 Some sur-geons initially advocated performing only revascularization in cases of moderate ischemic MR with the idea that revasculariz-ing viable myocardium would lead to improvements in LV func-tion and effect reverse remodeling, ultimately contributing to a decrease in MR. While several


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Surgery_Schwartz. ischemic MR with the idea that revasculariz-ing viable myocardium would lead to improvements in LV func-tion and effect reverse remodeling, ultimately contributing to a decrease in MR. While several studies, including a recent large, multicenter, randomized, controlled trial, have shown that MR often persists following revascularization alone, the addition of a mitral valve annuloplasty in those studies did not improve long-term functional status or survival in patients with isch-emic MR.189-192 Nevertheless, other studies have shown that the persistence of MR after CABG is associated with a decreased survival rate and that CABG alone only has modest effects on reducing MR at 1 month follow-up.184 As a result, some centers continue to repair moderate MR in this patient population. Indi-cations for surgery in ischemic MR patients in the absence of revascularization options are even less well defined.For patients with functional MR, the goal of mitral valve surgery is to avoid or


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Surgery_Schwartz. for surgery in ischemic MR patients in the absence of revascularization options are even less well defined.For patients with functional MR, the goal of mitral valve surgery is to avoid or postpone transplantation in eligible patients. Mitral valve repair has been considered the procedure of choice when surgery is indicated for secondary MR. How-ever, in patients with severe ischemic MR, a recent randomized, multicenter trial showed improved late freedom from moderate or severe recurrent MR with mitral valve replacement compared to repair (2.3% vs. 32.6%, P <0.001).141 There was not a signifi-cantly higher mortality in the replacement group in this study.141 Brunicardi_Ch21_p0801-p0852.indd 83201/03/19 5:32 PM 833ACQUIRED HEART DISEASECHAPTER 21Table 21-13Data guidelines for surgical intervention for secondary mitral regurgitationCLINICAL SETTINGCLASS OF RECOMMENDATIONLEVEL OF EVIDENCEChronic Ischemic MR (ESC Guidelines)• Severe MR, LVEF >30%, undergoing CABGIC• Moderate MR,


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Surgery_Schwartz. intervention for secondary mitral regurgitationCLINICAL SETTINGCLASS OF RECOMMENDATIONLEVEL OF EVIDENCEChronic Ischemic MR (ESC Guidelines)• Severe MR, LVEF >30%, undergoing CABGIC• Moderate MR, undergoing CABG, if mitral repair is feasibleIIaC• Severe MR, symptomatic patients, LVEF <30%, candidate for revascularizationIIaC• Severe MR, LVEF >30%, no option for revascularization, refractory to optimal medical therapy, low comorbidityIIbCChronic Functional MR (ESC and ACC/AHA Guidelines)• Chronic severe MR due to LV dysfunction, EF <30%, persistent NYHA class III-IV, symptoms despite optimal medical therapyIIbCMR = mitral regurgitation; ESC = European Society of Cardiology; CABG = coronary artery bypass grafting; LVEF = left ventricular ejection fraction; LV = left ventricle; ACC = American College of Cardiology; AHA = American Heart Association; NYHA = New York Heart Association.In patients with poor LV function, dilated LV, and severe MR with significant leaflet tethering, we favor MV


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Surgery_Schwartz. College of Cardiology; AHA = American Heart Association; NYHA = New York Heart Association.In patients with poor LV function, dilated LV, and severe MR with significant leaflet tethering, we favor MV replacement with preservation of the subvalvular apparatus. Bioprosthetic valve is usually used due to the poor late survival in this group of patients. Currently, for patients undergoing repair recom-mendations are to use a semirigid or rigid annuloplasty ring to downsize the mitral annulus.184 There have also been various techniques proposed to correct the papillary muscle displace-ment, but most reports are single center, retrospective, and small. Mitral valve replacement with preservation of the sub-valvular apparatus is indicated when repair is not feasible due to severe tethering of the leaflets or massive LV dilation.Outcomes from surgery vary among centers and among patients in this heterogeneous group. Operative mortality ranges between 0% and 9% in most modern series.184


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Surgery_Schwartz. of the leaflets or massive LV dilation.Outcomes from surgery vary among centers and among patients in this heterogeneous group. Operative mortality ranges between 0% and 9% in most modern series.184 Generally speak-ing, mortality and recurrence rates are higher and long-term prognosis is worse compared to outcomes for primary MR. Recurrent MR is as high as 15% to 30% in some series, and 5-year mortality is between 44% and 48%.184,193,194 Some reduc-tions in left atrial dimension and LV reverse remodeling may be achieved.195Left Ventricular Aneurysmorrhaphy and Surgical Ventricular RestorationPathophysiology of Ventricular Aneurysms. A transmural infarction of approximately 5% to 10% of the myocardium may result in formation of an LV aneurysm as necrotic myocardium is replaced by fibrous tissue. This usually occurs 4 to 8 weeks following the infarct. In the last decade, prompt revasculariza-tion of the culprit artery by either surgical or interventional tech-niques generally results in


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Surgery_Schwartz. This usually occurs 4 to 8 weeks following the infarct. In the last decade, prompt revasculariza-tion of the culprit artery by either surgical or interventional tech-niques generally results in sparing of the subepicardial muscle while the subendocardial muscle remains necrotic.196 There-fore, it is not uncommon for the LV wall to show both living myocardium during thallium testing and an akinetic zone on echocardiogram or angiogram. It has been demonstrated that once more than 20% of the myocardium is necrosed there is irreversible progression to ventricular dilation and failure.197 Once heart failure develops after postinfarction remodeling, the 1-year mortality reaches 32% despite current therapies.198 The classic aneurysm is a 4 to 6 mm thick scar, which bulges out-ward in paradoxical motion as the LV contracts during systole. More than 80% develop in the anteroseptal and apical portions of the left ventricle as a result of left anterior descending artery occlusion. The rest are


Surgery_Schwartz

Surgery_Schwartz. motion as the LV contracts during systole. More than 80% develop in the anteroseptal and apical portions of the left ventricle as a result of left anterior descending artery occlusion. The rest are inferior in location and the result of cir-cumflex or right coronary occlusion.This patient population typically suffers from associated ventricular arrhythmias for several reasons. First, electrical dys-synchrony results from postinfarction remodeling, and triggers for ventricular arrhythmias typically occur in the scar border zone in patients with ischemic cardiomyopathy.199,200 Second, increased ventricular volume causes high wall stress and stretch, and stretch has been shown to be arrhythmogenic.201 Third, LV aneurysms represent an independent risk factor for SCD after MI.202 Surgical ventricular restoration (SVR) addresses each of these issues by removing the anatomic substrate during resection of the postinfarct scar and/or aneurysm, accomplishing volume reduction and mechanical


Surgery_Schwartz

Surgery_Schwartz. ventricular restoration (SVR) addresses each of these issues by removing the anatomic substrate during resection of the postinfarct scar and/or aneurysm, accomplishing volume reduction and mechanical resynchronization and relieving ischemia through complete revascularization and reduction in myocardial wall tension and oxygen demand.Clinical Presentation and Diagnosis. Symptoms of LV aneurysms include angina, CHF, ventricular arrhythmias, and, rarely, embolic phenomenon. Rupture is extremely uncommon. Patients generally present for coronary artery bypass or during evaluation of CHF or arrhythmias. While transthoracic echo-cardiography gives pertinent information regarding LV func-tion, size, mitral valve function, and the presence of thrombus, it is generally accepted that cardiac MRI is the best diagnostic modality to accurately identify areas of scar and viable tissue and to best define ventricular geometry.197Surgical Treatment and Results. In 1985, Vincent Dor described a surgical


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Surgery_Schwartz. best diagnostic modality to accurately identify areas of scar and viable tissue and to best define ventricular geometry.197Surgical Treatment and Results. In 1985, Vincent Dor described a surgical technique called the endoventricular cir-cular patch plasty that was intended to improve geometric reconstruction compared with the standard linear repair in LV aneurysm surgery. SVR is a somewhat broader term that arose from surgical repair of ventricular aneurysms and has now come to be applied to a group of surgical procedures designed to correct the effects of postinfarction ventricular remodeling. It is also sometimes referred to as surgical ventricular remodel-ing or reconstruction, surgical anterior ventricular endocardial reconstruction (SAVER), or the Dor procedure. SVR is specifi-cally intended to reduce the size and sphericity of the LV by Brunicardi_Ch21_p0801-p0852.indd 83301/03/19 5:32 PM 834SPECIFIC CONSIDERATIONSPART IIexcluding akinetic and dyskinetic areas, most often


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Surgery_Schwartz. intended to reduce the size and sphericity of the LV by Brunicardi_Ch21_p0801-p0852.indd 83301/03/19 5:32 PM 834SPECIFIC CONSIDERATIONSPART IIexcluding akinetic and dyskinetic areas, most often by using a circular patch inserted inside the ventricle on contractile myo-cardium (Fig. 21-12A,B).Candidates for SVR are typically patients who have had a remote anterior or anteroseptal myocardial infarction, signifi-cant ventricular enlargement with a significant area of akinetic or dyskinetic myocardium, a discrete aneurysm, a clinical pic-ture consistent with heart failure (LVEF <40%), retained func-tion of the basilar and lateral portions of the heart, and good right ventricular function. These patients should also be candi-dates for repair of any other concomitant cardiac disease. Dor currently emphasizes the importance of complete revasculariza-tion and repair of any mitral pathology at the time of operative SVR. In patients with spontaneous (13%) or inducible (25%) ventricular


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Surgery_Schwartz. currently emphasizes the importance of complete revasculariza-tion and repair of any mitral pathology at the time of operative SVR. In patients with spontaneous (13%) or inducible (25%) ventricular tachycardia (VT), it is additionally necessary to per-form nonguided endocardial resection and cryoablation encir-cling the resected area.197Results with this approach have been good in treating both heart failure and its sequelae, such as VT. In Dor’s series of 1150 patients, the operative mortality varied based on the LVEF, ranging from 1% (patients with EF >40%) to 13% (patients with EF <30%), and the 5-year survival approached 85%.197 Overall, more than 80% of survivors either stabilized or improved, and the quality of life was shown to improve significantly by 6 months after the Dor procedure.203 This is likely due in part to the fact that the Dor procedure restores LV geometry, resulting in a mean ejection fraction increase between 10% and 15%, with significant alleviation of


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Surgery_Schwartz. procedure.203 This is likely due in part to the fact that the Dor procedure restores LV geometry, resulting in a mean ejection fraction increase between 10% and 15%, with significant alleviation of symptoms.197,204-206 These data are rein-forced by the international RESTORE group, which examined SVR in a registry of 1198 postinfarction patients between 1998 and 2003.207 They found that 5-year overall freedom from hos-pital readmission for CHF was 78%. Moreover, 67% of patients had preoperative NYHA class III or IV symptoms, whereas 85% of patients were NYHA functional class I or II postoperatively.With respect to VT, Dor et al reported on 106 patients with ischemic ventricular arrhythmias that underwent recon-struction for postinfarction LV aneurysm and visually directed endocardiectomy plus or minus cryoablation and coronary revascularization.208 At a mean follow-up of 21.3 months, only 10.8% of patients had inducible VT, and no spontaneous VT was documented. Results from similar


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Surgery_Schwartz. plus or minus cryoablation and coronary revascularization.208 At a mean follow-up of 21.3 months, only 10.8% of patients had inducible VT, and no spontaneous VT was documented. Results from similar series have also been excellent,197,206,209 but the efficacy of left ventricular restoration alone has been controversial.210,211 Inferior results seen in some Figure 21-12. Surgical ventricular restoration of a ventricular aneurysm using the Dor procedure. A. The size and sphericity of the left ventricle are reduced by excluding akinetic and dyskinetic areas. B. Most often this is completed using a circular patch inserted inside the ventricle on contractile myocardium.series have been attributed to failure to perform endocardial resection and/or cryoablation at the border of the transitional zone, as well as differences in stimulation protocols and pos-sible inadequate volume reduction of the ventricle.A large, randomized, multicenter study, the STICH trial, concluded that adding SVR to


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Surgery_Schwartz. zone, as well as differences in stimulation protocols and pos-sible inadequate volume reduction of the ventricle.A large, randomized, multicenter study, the STICH trial, concluded that adding SVR to reduce ventricular volume to CABG does not improve symptoms or exercise tolerance and fails to lower death rate or cardiac rehospitalization compared to CABG alone.176 While this trial has some shortcomings, it has resulted in a marked decrease in referrals for this procedure. The main problem is that the LV volume was reduced by only 19% in the STICH trial, reflecting an inadequate repair as determined by the Surgery Therapy Committee, whose “acceptable STICH procedure” guideline required a 30% reduction at the 4-month postoperative cardiac MRI.212 Previous studies have reported an average reduction of end-systolic volume index (ESVI) of 40% with a range between 30% and 58%, suggesting that the STICH SVR procedure may have involved an inadequately small LV plication or limited


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Surgery_Schwartz. average reduction of end-systolic volume index (ESVI) of 40% with a range between 30% and 58%, suggesting that the STICH SVR procedure may have involved an inadequately small LV plication or limited intracavitary reconstruction.212 Moreover, this trial enrolled 13% of patients who had never had an MI and changed criteria such that enrollment required documented LV anterior wall dysfunction rather than demonstration of scar. This could have captured patients with hibernating myocardium that would recover following CABG alone. Dor subsequently pub-lished the results of 117 patients who would have been eligible for the STICH trial and demonstrated durable improvement in left ventricular function.213 However, this was a single-center, retrospective experience. Caution should be exercised so as not to broadly extrapolate the results of the STICH trial and inap-propriately deny appropriate patients effective treatment. This remains an area of controversy.With the recent advances in


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Surgery_Schwartz. so as not to broadly extrapolate the results of the STICH trial and inap-propriately deny appropriate patients effective treatment. This remains an area of controversy.With the recent advances in percutaneous interventions, the Parachute device has been trialed in human subjects. It is composed of a self-expanding nitinol frame covered with an impermeable fluoropolymer that is deployed into the LV apex walling off akinetic or dyskinetic segments of the LV. The PARACHUTE trial reported 3-year echocardiographic and clinical outcomes of patients with ischemic heart failure who underwent placement of the Parachute device as a feasibility and safety study. They demonstrated that of the 31 patients who received the device, there was improvement or maintenance of NYHA functional class in 85% as well as significant reduction of the LV EDV index.198Brunicardi_Ch21_p0801-p0852.indd 83401/03/19 5:32 PM 835ACQUIRED HEART DISEASECHAPTER 21Mechanical Circulatory SupportIntra-Aortic Balloon


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Surgery_Schwartz. as well as significant reduction of the LV EDV index.198Brunicardi_Ch21_p0801-p0852.indd 83401/03/19 5:32 PM 835ACQUIRED HEART DISEASECHAPTER 21Mechanical Circulatory SupportIntra-Aortic Balloon Pump. The intra-aortic balloon pump (IABP) is a commonly used device for mechanical circulatory support and has been in use since 1968. The device is inserted percutaneously through a peripheral artery into the thoracic aorta. The balloon is synchronized so that it inflates during dias-tole and deflates during systole, resulting in augmentation of diastolic perfusion of the coronary arteries and decreased after-load. Typically, this improves cardiac index and decreases both preload and myocardial oxygen consumption.Common indications for use of an IABP is cardiogenic shock during or following cardiac catheterization or cardiac sur-gery. It also is utilized for preoperative stabilization of high-risk patients with either severe coronary artery disease, LV dysfunc-tion, or refractory,


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Surgery_Schwartz. cardiac catheterization or cardiac sur-gery. It also is utilized for preoperative stabilization of high-risk patients with either severe coronary artery disease, LV dysfunc-tion, or refractory, unstable angina. Kang et al have reported that risk-adjusted mortality was significantly lower for selected high-risk patients undergoing open heart surgery when a pre-operative IABP was used.214 In 2012, Thiele et al reported their data following a randomized, prospective, multicenter clinical trial looking at the outcome of using intra-aortic balloon pump in the treatment of cardiogenic shock complicating acute myo-cardial infarction in patients who underwent early revasculariza-tion (by means of percutaneous coronary intervention or bypass surgery) (IABP-SHOCK II trial).215 IABP did not significantly reduce 30-day mortality in this group of patients. Addition-ally, they reported no significant differences in secondary end points, including the time to hemodynamic stabilization, the length of


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Surgery_Schwartz. reduce 30-day mortality in this group of patients. Addition-ally, they reported no significant differences in secondary end points, including the time to hemodynamic stabilization, the length of stay in the intensive care unit, serum lactate levels, the dose and duration of catecholamine therapy, renal function, and major complications including major bleeding and peripheral ischemia.215Generally, an IABP is used for a few days and the amount of support is weaned as the patient’s condition improves. Mor-bidity associated with device use is typically minimal; however, in one series of 911 patients undergoing CABG who received an IABP, there was a 12% incidence of minor or major vascu-lar complications, including an approximately 3% incidence of limb ischemia requiring thromboembolectomy. This is the most serious complication of IABP placement. To prevent this prob-lem, frequent lower extremity neurovascular checks are neces-sary while an IABP is in place.216Ventricular Assist Device


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Surgery_Schwartz. This is the most serious complication of IABP placement. To prevent this prob-lem, frequent lower extremity neurovascular checks are neces-sary while an IABP is in place.216Ventricular Assist Device Indications and Cannulation. Patients in need of ventricular assist devices (VADs) may have preexisting chronic heart failure, refractory ventricular arrhythmias, or acute heart failure following an MI, cardiopul-monary arrest, viral illness, pregnancy, or cardiotomy. Device therapy is intended to preserve end-organ perfusion and func-tion and may be categorized as shortor long-term support for the left heart, the right heart, or both. In general, VADs may be used rarely for support while the heart recovers (bridge to recovery, BTR), while the patient waits for a heart transplant (bridge to transplant, BTT) or increasingly more commonly to treat a chronic heart failure patient who is not a transplant candidate (destination therapy, DT). The Interagency Registry for Mechanically Assisted


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Surgery_Schwartz. transplant, BTT) or increasingly more commonly to treat a chronic heart failure patient who is not a transplant candidate (destination therapy, DT). The Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) database, a joint effort by the NHLBI, FDA, CMS, academia, and industry to prospectively track patient outcomes, reported that in 2015 and 2016 indications for device implantation were BTR (0.2%), BTT listed (26.4%), BTT likely (15.5%), BTT moderate (7.7%), BTT unlikely (2.5%), DT (49.2%), and res-cue therapy (0.5%).217 The percentage of patients receiving a VAD as destination therapy has markedly increased over the last decade as results and devices improved.Left ventricular assist devices (LVADs) provide support for the failing heart by unloading blood from the left ventricle and pumping it into the aorta. Cannulas may be inserted into the LV apex or the left atrium for inflow into the pump, and return is through an arterial cannula or graft sewn to


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Surgery_Schwartz. the left ventricle and pumping it into the aorta. Cannulas may be inserted into the LV apex or the left atrium for inflow into the pump, and return is through an arterial cannula or graft sewn to either the ascending or descending aorta. For right-sided devices, inflow drainage is most often from a cannula in the right atrium, and blood is returned through a graft sewn to the pulmonary artery or right ventricular outflow tract.Left Ventricular Assist Devices. The first generation LVADs were pulsatile devices. They provided adequate support for the heart but were limited by their large size and durabil-ity.218 More recently, continuous-flow LVADs based on rotary pump technology have been introduced. These devices are smaller, quieter, and durable enough for long term support. The two most commonly used devices today are the HeartMate II (Thoratec, Pleasanton, CA) and the HeartWare HVAD (Heart-Ware, Inc., Framingham, MA) (Figs. 21-13A,B and 21-14A,B). These devices differ in that the


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Surgery_Schwartz. commonly used devices today are the HeartMate II (Thoratec, Pleasanton, CA) and the HeartWare HVAD (Heart-Ware, Inc., Framingham, MA) (Figs. 21-13A,B and 21-14A,B). These devices differ in that the HeartMate II is implanted sub-diaphragmatically, whereas the smaller HeartWare HVAD is implanted within the pericardium. Frequently used short-term support devices include the Abiomed BVS 5000 (Abiomed, Inc., Danvers, MA) and the CentriMag (Thoratec), which are both extracorporeal pumps, as well as the Impella (Abiomed), which may be inserted percutaneously. These devices are com-monly used in either post-MI or postcardiotomy heart failure. They have the benefit of faster and easier insertion, making them ideal rescue devices and allowing time for patient transfer to a tertiary referral center, device weaning, transplantation, or transition to a permanent VAD as DT or BTT.Bridge to Recovery. The ideal clinical situation would be for all LVADs to be temporary with the goal of myocardial


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Surgery_Schwartz. device weaning, transplantation, or transition to a permanent VAD as DT or BTT.Bridge to Recovery. The ideal clinical situation would be for all LVADs to be temporary with the goal of myocardial recov-ery. However, as noted previously, this is rare with only 0.2% of devices in the most recent INTERMACS data placed with intent for bridge to recovery.217 The LVAD Working Group Recovery Study, a prospective multicenter trial investigating myocardial recovery in BTT patients, has shown significant improvements in left ventricular ejection fraction and significant reductions in left ventricular end-diastolic diameter following support with continuous flow pumps, but myocardial recovery resulting in device explantation was still only seen in six patients (9%).219 Current data suggest that significant reverse remodeling is more likely to occur in the young and those with myocarditis.220Nevertheless, some encouraging results have been reported using a combination of treatment modalities. In a


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Surgery_Schwartz. reverse remodeling is more likely to occur in the young and those with myocarditis.220Nevertheless, some encouraging results have been reported using a combination of treatment modalities. In a few small studies of patients with LVADs inserted for nonischemic cardiomyopathy, deliberate and aggressive medical therapy, including the β2-agonist clenbuterol, resulted in successful LVAD explantation in 69% to 73% of patients,221,222 but these results have been difficult to replicate. Moreover, early results from clinical trials using stem cell therapy to treat patients with ischemic cardiomyopathy suggest that stem cells may be another adjuvant treatment with potential to aid in myocardial recovery.223,224Bridge to Transplant. LVADs are used as a bridge to trans-plant in patients who are candidates for heart transplantation but are not predicted to survive the waiting list period due to sequelae of cardiac failure, including end-organ dysfunc-tion, rising pulmonary artery pressures,


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Surgery_Schwartz. candidates for heart transplantation but are not predicted to survive the waiting list period due to sequelae of cardiac failure, including end-organ dysfunc-tion, rising pulmonary artery pressures, escalating inotrope Brunicardi_Ch21_p0801-p0852.indd 83501/03/19 5:32 PM 836SPECIFIC CONSIDERATIONSPART IIABFigure 21-13. The HeartMate II LVAD viewed from the (A) outside and (B) inside. The device is an axial flow, rotary pump that produces no pulsatile action. The pump contains a magnet, and the rotor assembly functions by the electromotive force generated by the motor. The result is that blood is propelled from the inflow cannula to systemic circulation at flows up to 10 L/min. (HeartMate, HeartMate II and St. Jude Medical are trademarks of St. Jude Medical, LLC or its related companies. Reproduced with permission of St. Jude Medical, ©2017. All rights reserved.)ABFigure 21-14. The HeartWare HVAD system. A. Both the device controller and batteries are held in a wearable carrying


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Surgery_Schwartz. Reproduced with permission of St. Jude Medical, ©2017. All rights reserved.)ABFigure 21-14. The HeartWare HVAD system. A. Both the device controller and batteries are held in a wearable carrying case and con-nected to the ventricular assist device through the driveline. B. The main component is a centrifugal blood pump, called the HVAD, which is implanted within the pericardium. The only moving part in the device, the impeller, is suspended within the pump using magnets and thrust bearings. Similar to the HeartMate II, it can deliver a flow rate of up to 10 L/min. (Reproduced with permission of Medtronic, Inc.)requirements, malignant ventricular arrhythmias, and risk for sudden death. Due to the scarcity of donor organs, the improved survival seen with LVAD usage has resulted in more patients remaining alive while on the transplantation waiting list. It is currently estimated that 35% of patients who go on to receive a heart transplant have had a previous LVAD implantation, although


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Surgery_Schwartz. remaining alive while on the transplantation waiting list. It is currently estimated that 35% of patients who go on to receive a heart transplant have had a previous LVAD implantation, although at more aggressive tertiary care facilities this number may be as high as 75% to 90%.172The HeartMate II pump was evaluated as a BTT in an observational, prospective multicenter trial of 133 patients with persistent NYHA class IV heart failure despite optimal medical management who were status 1A or 1B on the transplant list.225 At 6 months, 100 patients (75%) had undergone transplantation, had cardiac recovery, or continued on mechanical support while remaining eligible for transplantation. There were significant improvements in both quality of life and functional status with device therapy. At 3 months, 81% of patients were in class I or II heart failure. Moreover, complications, including bleeding requir-ing reoperation, stroke, drive-line infection, and need for right ventricular assist


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Surgery_Schwartz. 3 months, 81% of patients were in class I or II heart failure. Moreover, complications, including bleeding requir-ing reoperation, stroke, drive-line infection, and need for right ventricular assist device support, were significantly less frequent than with the previous generation HeartMate XVE.226 These data led to FDA approval of the HeartMate II as a BTT LVAD in 2008, and clinical use of the device increased dramatically. More recently, a multicenter, prospective trial compared the Heart-Ware HVAD to contemporaneously inserted devices for use as a BTT.227 This trial demonstrated noninferiority of the HeartWare HVAD, but in contrast to the 2007 trial, approximately 90% of patients in both groups were transplanted, explanted for recovery, or remained alive and eligible for transplant with LVAD support at 6 months. Most important, data suggest that patients bridged to transplant with an LVAD in the current era experience similar shortand long-term posttransplant survival and


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Surgery_Schwartz. with LVAD support at 6 months. Most important, data suggest that patients bridged to transplant with an LVAD in the current era experience similar shortand long-term posttransplant survival and complications and do not have a higher incidence of allosensitization compared to standard cardiac transplant patients.228,229Brunicardi_Ch21_p0801-p0852.indd 83601/03/19 5:32 PM 837ACQUIRED HEART DISEASECHAPTER 21Most recently, in 2017, Mehra et al reported their multi-center outcome (Mechanical Circulatory Support Therapy with HeartMate 3 trial—MOMENTUM 3) comparing the safety and effectiveness of centrifugal-flow pump (HeatMate 3) to the axial-flow pump (HeatMate II).230 Implantation of a fully mag-netically levitated centrifugal-flow pump (HeartMate 3) was associated with better outcomes at 6 months than was implanta-tion of an axial-flow pump (HeartMate II). The improved out-comes were primarily due to the lower rate of reoperation for pump malfunction. Additionally, no patients in the


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Surgery_Schwartz. 6 months than was implanta-tion of an axial-flow pump (HeartMate II). The improved out-comes were primarily due to the lower rate of reoperation for pump malfunction. Additionally, no patients in the HeartMate 3 group were suspected or found to have pump thrombosis.230Destination Therapy. The Randomized Evaluation of Mechan-ical Assistance for Treatment of Congestive Heart Failure (REMATCH) trial was conducted to compare the efficacy of LVAD insertion against optimal medical management in patients with NYHA class IV heart failure. While the pulsatile devices used in this trial had high failure rates, poor durability, and high associated mortality, there was still a clear survival ben-efit in patients treated with LVADs. This led to the FDA approval of the first LVADs for destination therapy in 2002.218Subsequent trials have proven the increased efficacy of second-generation devices for DT. In one such landmark trial, patients with advanced heart failure who were ineligible for


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Surgery_Schwartz. therapy in 2002.218Subsequent trials have proven the increased efficacy of second-generation devices for DT. In one such landmark trial, patients with advanced heart failure who were ineligible for transplantation were randomized in a 2:1 ratio to either a Heart-Mate II or HeartMate XVE.231 While both groups showed sig-nificant improvements in functional capacity and quality of life, actuarial survival at 2 years was superior for HeartMate II patients (58% vs. 24%, P = 0.008) and adverse event rates were signifi-cantly lower. These data established the benefit of continuous flow LVADs over optimal medical management for end-stage heart failure, and led to FDA approval of the HeartMate II for DT in 2010. In certain populations, 2-year survival with the HeartMate II is now 80%.232 Several smaller third generation devices are in various stages of development or clinical trials. Some of these devices eliminate the drive line by using alter-native energy sources, thereby removing a


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Surgery_Schwartz. smaller third generation devices are in various stages of development or clinical trials. Some of these devices eliminate the drive line by using alter-native energy sources, thereby removing a significant nidus for device infections. Long-term outcomes with these devices are expected to continue to improve, approaching that of cardiac transplantation and providing a viable solution to organ short-age for many patients.232 In 2013, Slaughter et al reported their multicenter clinical trial outcome to evaluate the HeartWare Ventricular Assist Device (HVAD) system for BTT in patients with advance heart failure in the United States (ADVANCE BTT trial).233 The use of the HeartWare pump as a BTT continued to demonstrate a high 180-day survival rate (91%) despite a low rate of transplant. Adverse event rates were similar or better than those observed in historical BTT trials, despite longer exposure times due to longer survival and lower transplant rates.233Current eligibility criteria for


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Surgery_Schwartz. event rates were similar or better than those observed in historical BTT trials, despite longer exposure times due to longer survival and lower transplant rates.233Current eligibility criteria for mechanical support as des-tination therapy include (a) NYHA class III or IV heart failure despite guideline-directed medical therapy including cardiac resynchronization therapy if indicated; (b) peak oxygen con-sumption <12 mL/kg per min or failure to wean from continuous IV inotropes; (c) left ventricular ejection fraction <25%; and (d) presence of a contraindication for heart transplantation (i.e., age >65 years, irreversible pulmonary hypertension, chronic renal failure, insulin-dependent diabetes with end-organ dam-age, or other clinically significant comorbidities).172,234 Once a patient has an LVAD inserted as DT, close and intensive follow-up by a multidisciplinary heart failure team is required in order to optimize medical therapy, reduce device-related morbidity, and improve


Surgery_Schwartz

Surgery_Schwartz. has an LVAD inserted as DT, close and intensive follow-up by a multidisciplinary heart failure team is required in order to optimize medical therapy, reduce device-related morbidity, and improve survival.6It is also important to keep in mind that while some con-traindications to transplantation are irreversible, others can be modified. As such, approximately 10% of patients implanted with an initial strategy of destination therapy become BTT patients,172 and in some patients, the LVAD itself facilitates this transition. For example, an improvement in mean pulmonary vascular resistance was reported following implantation of the HeartMate II in patients with end-stage heart failure (2.1 vs. 3.6 Woods units, P <0.001).235 These data are also relevant to patients that receive LVADs as a bridge to decision.Right Ventricular Assist Devices and Biventricular Assist DevicesMost patients who present with advanced heart failure and a failing left ventricle also have some degree of right


Surgery_Schwartz

Surgery_Schwartz. a bridge to decision.Right Ventricular Assist Devices and Biventricular Assist DevicesMost patients who present with advanced heart failure and a failing left ventricle also have some degree of right ventricu-lar dysfunction, but the majority of these patients do well with only an LVAD. However, implantation of an LVAD may cause acute worsening of tricuspid regurgitation and exacerbations of right heart failure through leftward deviation of the intraven-tricular septum and as a result of the significant volume-loading and transfusion requirement that is often necessary to achieve adequate flows postoperatively. Overall, approximately 20% of HeartMate II BTT patients had persistent right ventricular failure (RVF) requiring either a subsequent RVAD (6%) or intravenous inotropic support for >14 days (14%), and these patients had significantly worse 6-month survival compared to those without RVF (71% vs. 89%, P <0.001).236 Typically, mechanical right-ventricular support is temporary with


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Surgery_Schwartz. >14 days (14%), and these patients had significantly worse 6-month survival compared to those without RVF (71% vs. 89%, P <0.001).236 Typically, mechanical right-ventricular support is temporary with intent to wean the device, and isolated right-ventricular assist devices are unusual.Biventricular support is most commonly indicated for acute cardiogenic shock after an MI or postcardiotomy heart failure. Biventricular support is temporary, although some patients may be successfully bridged to transplant or perma-nent left-sided assist devices. There is currently no destination therapy device for biventricular failure.Total Artificial HeartThe total artificial heart (TAH, SynCardia Systems, Tucson, AZ) is currently indicated as a bridge to transplant for patients in biventricular failure, particularly for those who are critically ill and too large for extracorporeal BiVAD support. Unlike ven-tricular assist devices, the TAH replaces the entire heart. The ven-tricles of the TAH are


Surgery_Schwartz

Surgery_Schwartz. particularly for those who are critically ill and too large for extracorporeal BiVAD support. Unlike ven-tricular assist devices, the TAH replaces the entire heart. The ven-tricles of the TAH are implanted orthotopically to the atrial cuffs on the ventricular side of the AV groove, and the outflow conduits are attached to the great vessels. This approach has the benefit of obviating the hemodynamic influence of pulmonary hyperten-sion, right heart failure, myocardial or valvular problems, cardiac arrhythmias, and inotropic agents.237 While this device has failed to reach its potential as a replacement for cardiac transplantation, the TAH has achieved favorable results as a BTT with a >70% survival in selected centers.238-240 However, at most centers results with the TAH have been suboptimal, and it is not frequently used. A total of 226 TAH implants between 2013 and 2016 were reported to INTERMACS database. One-year and 2-year sur-vival was reported at 52% and 37%, respectively.


Surgery_Schwartz

Surgery_Schwartz. and it is not frequently used. A total of 226 TAH implants between 2013 and 2016 were reported to INTERMACS database. One-year and 2-year sur-vival was reported at 52% and 37%, respectively. Compare to the previously reported survival (2006 through 2012), no significant improvement in survival was noted with time.217SURGERY FOR ARRHYTHMIASThe success of catheter-based ablation and implantable cardio-verter defibrillators (ICDs) has significantly diminished refer-rals for the surgical treatment of arrhythmias such as ventricular Brunicardi_Ch21_p0801-p0852.indd 83701/03/19 5:32 PM 838SPECIFIC CONSIDERATIONSPART IItachycardia, Wolff-Parkinson-White syndrome, atrial flutter, and atrioventricular nodal reentry. On the other hand, the intro-duction of surgical ablation modalities such as radiofrequency and cryothermal energy, has simplified the surgical treatment of atrial fibrillation and has led to an increase in the number of surgical procedures performed annually for AF, although


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Surgery_Schwartz. radiofrequency and cryothermal energy, has simplified the surgical treatment of atrial fibrillation and has led to an increase in the number of surgical procedures performed annually for AF, although this has plateaued in recent years.241,242Atrial FibrillationEpidemiology of Atrial Fibrillation. AF remains the most common arrhythmia in the world with an overall prevalence of 0.4% to 1% that increases to 8% in those older than 80 years old.243 The most serious complication of AF is thromboembo-lism with resultant stroke,244 but serious morbidity and mortality may also result from hemodynamic compromise due to loss of atrial contraction and exacerbations of CHF from atrioventricu-lar asynchrony and tachycardia-induced cardiomyopathy.Medical Management. Most patients are treated medically, but the shortcomings of pharmacological management have left an important role for interventional therapies. Antiarrhythmic medications have been limited by modest efficacy and sig-nificant


Surgery_Schwartz

Surgery_Schwartz. but the shortcomings of pharmacological management have left an important role for interventional therapies. Antiarrhythmic medications have been limited by modest efficacy and sig-nificant proarrhythmic and systemic toxicities.245 Conversely, rate control strategies leave the patient in AF, do not address the impaired hemodynamics or symptoms associated with this arrhythmia, and may render subsequent attempts at rhythm con-trol therapies less effective for younger patients who may suf-fer irreversible cardiac remodeling due to the prolonged period of time in AF. Additionally, AF is associated with a fivefold greater risk of ischemic stroke or systemic embolism compared with normal sinus rhythm. Annual risk of major bleeding in those on anticoagulation is estimated at 1.2%.246Restoration of normal sinus rhythm has several potential benefits over other strategies.247-249 These include improvement in atrial systolic function, which improves cardiac output and often symptoms of CHF;


Surgery_Schwartz

Surgery_Schwartz. of normal sinus rhythm has several potential benefits over other strategies.247-249 These include improvement in atrial systolic function, which improves cardiac output and often symptoms of CHF; lowered risks of stroke; potential free-dom from anticoagulation; and likely reversal of atrial structural and/or electrical remodeling.Indications for Surgical Management. Consensus guide-lines published by the Heart Rhythm Society state that surgical ablation for atrial fibrillation is indicated for (a) all symptom-atic AF patients undergoing other cardiac surgery; (b) selected asymptomatic AF patients undergoing cardiac surgery in which the ablation can be performed with minimal additional risk; and (c) symptomatic patients with lone AF who have failed medi-cal therapy and prefer a surgical approach, have failed one or more attempts at catheter ablation, or are poor candidates for catheter ablation.243 At our institution, relative indications for surgical ablation in patients with


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Surgery_Schwartz. approach, have failed one or more attempts at catheter ablation, or are poor candidates for catheter ablation.243 At our institution, relative indications for surgical ablation in patients with permanent AF that were not included in the consensus statement are (a) a contraindica-tion to long term anticoagulation for patients at high risk for stroke (CHADS2 score ≥2) and (b) a history of stroke while on therapeutic anticoagulation. Since the consensus statement was released, a multicenter, randomized, controlled trial of surgical ablation in patients undergoing mitral valve surgery showed a significant improvement in freedom from atrial fibrillation in patients receiving surgical ablation (63% vs. 29%, P <0.001).250 Controversially, this trial did not show a difference between left atrial and biatrial ablation; this may have been due to techni-cal issues with the operations.251 The STS has recently released guidelines for surgical ablation that give a Class I Level A rec-ommendation


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Surgery_Schwartz. and biatrial ablation; this may have been due to techni-cal issues with the operations.251 The STS has recently released guidelines for surgical ablation that give a Class I Level A rec-ommendation for concomitant surgical ablation at the time of mitral valve surgery and a Class I Level B-NR recommendation for concomitant surgical ablation at the time of AVR, CABG, or AVR-CABG.252The Cox-Maze IV Procedure. The first successful operation for atrial fibrillation, the Cox-Maze procedure, was introduced clinically in 1987 by James Cox. The procedure involved the completion of a maze-like pattern of surgical incisions across both the right and left atrial that were designed to interrupt the multiple macroreentrant circuits thought to be responsible for AF, while still allowing propagation of the sinus impulse, restoring atrioventricular synchrony, and preserving atrial trans-port function. While effective at eliminating AF and reducing the risk of thromboembolism, it was not widely


Surgery_Schwartz

Surgery_Schwartz. of the sinus impulse, restoring atrioventricular synchrony, and preserving atrial trans-port function. While effective at eliminating AF and reducing the risk of thromboembolism, it was not widely performed because it was technically difficult and significantly prolonged time on cardiopulmonary bypass. In 2002, the Cox-Maze IV, was introduced. The Cox-Maze IV uses a combination of bipo-lar radiofrequency (RF) ablation and cryoablation to effectively replace the majority of incisions that comprise the Cox-Maze III while significantly shortening cross-clamp time and reducing operative complexity.The Cox-Maze IV is performed on cardiopulmonary bypass through either a median sternotomy, often in combina-tion with other cardiac surgery or a right minithoracotomy.253,254 In most cases, the right atrial lesion set performed on the beat-ing heart, whereas the left atrial lesions are performed during cardioplegic arrest (Fig. 21-15).Results from the Cox-Maze IV procedure have been excellent.


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Surgery_Schwartz. atrial lesion set performed on the beat-ing heart, whereas the left atrial lesions are performed during cardioplegic arrest (Fig. 21-15).Results from the Cox-Maze IV procedure have been excellent. The Washington University group reported a series of 576 consecutive patients in 2015, demonstrating free-dom from atrial tachyarrhythmias in 92% of patients at 1 year and 73% of patients at 5 years postoperatively.255 Additionally, freedom from atrial tachyarrhythmias and antiarrhythmic drugs was 81% at 1 year and 61% at 5 years. A recent propensity-matched analysis showed that the addition of the Cox-Maze IV procedure to a routine cardiac surgery did not significantly increase postoperative morbidity or mortality and was associ-ated with improved late survival compared with patients with untreated AF and a similar survival to patients without a his-tory of AF.256 A propensity analysis has shown that results are similar between the traditional “cut-and-sew” maze (Cox-Maze III) and the


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Surgery_Schwartz. untreated AF and a similar survival to patients without a his-tory of AF.256 A propensity analysis has shown that results are similar between the traditional “cut-and-sew” maze (Cox-Maze III) and the Cox-Maze IV.257 This procedure is often successful in patients who are poor candidates for catheter-based ablation, such as those with large left atria and patients with long-standing persistent AF.The combination of surgical management of the left atrial appendage (LAA) and restoration of normal sinus rhythm after the Cox-Maze procedure significantly reduces stroke risk. It is our practice to stop warfarin at 3 months postoperatively in patients who are in normal sinus rhythm and without another indication for anticoagulation, regardless of CHA2DS2-VASc score. With this approach, the stroke rate following the Cox-Maze procedure off anticoagulation has been remarkably low (annual risk = 0.2%).258 In contrast, in one report the annual rate of intracranial hemorrhage in anticoagulated


Surgery_Schwartz

Surgery_Schwartz. rate following the Cox-Maze procedure off anticoagulation has been remarkably low (annual risk = 0.2%).258 In contrast, in one report the annual rate of intracranial hemorrhage in anticoagulated patients with AF was 0.9% per year, and the overall rate of major bleeding complications was 2.3% per year.259Left Atrial Lesion Sets. Some surgeons perform more lim-ited ablation procedures, such as isolated pulmonary vein isola-tion or lesion sets that are limited to the left side of the heart. This is done in order to further reduce the complexity of the pro-cedure and takes advantage of the fact that in most patients AF 7Brunicardi_Ch21_p0801-p0852.indd 83801/03/19 5:32 PM 839ACQUIRED HEART DISEASECHAPTER 21Figure 21-15. The Cox-Maze IV Lesion Set. A. The left atrial lesion set is comprised of right and left pulmonary vein isolation, connecting lesions between the left and right superior and inferior pulmonary veins, a lesion from the left atrial appendage excision site to the


Surgery_Schwartz

Surgery_Schwartz. comprised of right and left pulmonary vein isolation, connecting lesions between the left and right superior and inferior pulmonary veins, a lesion from the left atrial appendage excision site to the pulmonary vein, and a lesion to the mitral valve annulus. B. The right atrial lesion set consists of lines of ablation along the superior and inferior vena cavae, the free wall of the right atrium, and down to the tricuspid valve annulus. (Reproduced with permission from Weimar T, Bailey MS, Watanabe Y, et al: The Cox-maze IV procedure for lone atrial fibrillation: a single center experience in 100 consecutive patients, J Interv Card Electrophysiol. 2011 Jun;31(1):47-54.)ABoriginates from the pulmonary veins and posterior left atrium. However, there is seldom justification for limited lesion sets in experienced hands.While there is a high degree of variability in both the techniques and energy sources that have been attempted for left-sided atrial lesion sets, these procedures have all


Surgery_Schwartz

Surgery_Schwartz. sets in experienced hands.While there is a high degree of variability in both the techniques and energy sources that have been attempted for left-sided atrial lesion sets, these procedures have all incorpo-rated some subset of the left atrial lesion set of the Cox-Maze procedure. Pulmonary vein isolation is ubiquitously performed, and the LAA is often excised. Results differ greatly between series, including the recent CTSNet multicenter trial,250 but a meta-analysis of the published literature by Ad and colleagues revealed that a biatrial lesion set resulted in a significantly higher late freedom from AF compared with a left atrial lesion set alone (87% vs. 73%, P = 0.05).260 These results are not sur-prising, as our intraoperative mapping experience with such patients showed a distinct region of stable dominant frequency in the left atrium only 30% of the time.261 The dominant fre-quency was located in the right atrium 12% of the time and moved during the recording period in almost


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Surgery_Schwartz. region of stable dominant frequency in the left atrium only 30% of the time.261 The dominant fre-quency was located in the right atrium 12% of the time and moved during the recording period in almost half of all patients. It must also be kept in mind that recurrent right atrial flutter is a known complication of performing only the left atrial lesions. When it does occur, atrial flutter can be treated with catheter-based ablation; however, recurrent left atrial flutter can be very difficult to ablate.Pulmonary Vein Isolation. Pulmonary vein isolation (PVI) is an attractive therapeutic option because it can be performed off of cardiopulmonary bypass (CPB) through small or thora-coscopic incisions. The results of PVI have been variable and highly dependent on patient selection since outcomes are con-sistently worse in patients with longstanding persistent AF. In a study from Edgerton et al, only 56% of patients were free from AF at 6 months (35% off antiarrhythmic drugs), and with


Surgery_Schwartz

Surgery_Schwartz. are con-sistently worse in patients with longstanding persistent AF. In a study from Edgerton et al, only 56% of patients were free from AF at 6 months (35% off antiarrhythmic drugs), and with concomitant procedures, the success rate of PVI has been even lower.262 Several devices are available to close the LAA at the time of PVI. These include staplers and epicardial clips that can be placed without the need for CPB.263While surgical PVI has had poorer results than a Cox-Maze procedure, it has had superior results to catheter-based PVI. The Atrial Fibrillation Catheter Ablation Versus Surgi-cal Ablation Treatment (FAST) Trial, which was a two cen-ter, randomized clinical trial, compared catheter-based ablation to thoracoscopic PVI in patients with antiarrhythmic drug-refractory AF and either left atrial dilatation and hypertension or failed prior catheter-ablation.264 This study demonstrated that the 12-month freedom from AF and antiarrhythmic drugs was 37% for the catheter ablation


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Surgery_Schwartz. left atrial dilatation and hypertension or failed prior catheter-ablation.264 This study demonstrated that the 12-month freedom from AF and antiarrhythmic drugs was 37% for the catheter ablation group and 66% for the PVI group (P = 0.002).264SURGERY FOR PERICARDIAL DISEASEAcute PericarditisPericarditis is characterized by infiltration of the cellular and fibrous pericardium by inflammatory cells. The exact incidence and prevalence of pericarditis is unknown, but it is estimated that pericarditis is found in approximately 1% of autopsies and accounts for up to 5% of presentations of nonischemic chest pain.265,266 The etiologies of acute pericarditis are diverse and may result from primary pericardial disorders or occur sec-ondary to a systemic illness.267 In developed countries, 80% to 90% of cases are now considered idiopathic or related to a viral pathogen, but nonviral infection, autoimmune diseases, myocardial infarction, radiation, malignancy, endocrinopathy, myocarditis, aortic


Surgery_Schwartz

Surgery_Schwartz. of cases are now considered idiopathic or related to a viral pathogen, but nonviral infection, autoimmune diseases, myocardial infarction, radiation, malignancy, endocrinopathy, myocarditis, aortic dissection, uremia, trauma, pharmacologi-cal side effects, and previous cardiothoracic surgery must be included in the differential diagnosis. The relative incidences of peri-infarction pericarditis, which was once common, and post-cardiac injury syndrome have been dramatically reduced with the advent of thrombolytics and coronary angioplasty.267Clinical Presentation and Diagnosis. Diagnosis of acute pericarditis typically requires the identification of at least two of four cardinal features (Table 21-14). The presentation may be confused with several more common cardiopulmonary condi-tions, particularly myocardial infarction, making a careful his-tory and physical critical. Patients with pericarditis classically complain of sudden onset, retrosternal pain that may be pleuritic in nature.


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Surgery_Schwartz. myocardial infarction, making a careful his-tory and physical critical. Patients with pericarditis classically complain of sudden onset, retrosternal pain that may be pleuritic in nature. The pain may also be positional, with alleviation of pain when the patient is upright and leaning forward. Pain from pericarditis is typically sharp or stabbing, as opposed to the dull pain or pressure that is common with angina, and it typically does not crescendo. While both conditions cause pain that often radiates to the neck, arms, and shoulders, pericarditis pain may Brunicardi_Ch21_p0801-p0852.indd 83901/03/19 5:32 PM 840SPECIFIC CONSIDERATIONSPART IIuniquely radiate to the trapezius ridge due to innervation from the phrenic nerve.268-269The presence of a pericardial friction rub is pathogno-monic for pericarditis, but it tends to vary in intensity over time and may be absent in 15% to 65% of patients.265,268 As such, the sensitivity of this physical finding is dependent on the fre-quency


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Surgery_Schwartz. for pericarditis, but it tends to vary in intensity over time and may be absent in 15% to 65% of patients.265,268 As such, the sensitivity of this physical finding is dependent on the fre-quency and quality of auscultation. A pericardial friction rub is best heard at the left lower sternal border and is typically described as a high-pitched scratchy or squeaky sound with a triphasic cadence corresponding to the movement of the heart during atrial systole, ventricular systole, and early ventricular diastole. However, it may be monophasic or biphasic in up to 50% of patients.Electrocardiogram changes typically progress through four stages representing global subepicardial myocarditis and subsequent recovery. Pericarditis patients may have concave ST deflections with diffuse changes, spanning the leads of multiple coronary artery distributions, but ST segment abnormalities are absent in 20% to 40% of patients.270,271 Acute pericarditis should not result in the development of infarct


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Surgery_Schwartz. the leads of multiple coronary artery distributions, but ST segment abnormalities are absent in 20% to 40% of patients.270,271 Acute pericarditis should not result in the development of infarct patterns, such as Q waves or loss of R waves, and T-wave inversions from pericarditis tend to result later in the disease process after the ST segment has returned to baseline.Echocardiography is routinely performed in the evaluation of acute pericarditis. Its role is primarily to assess for a pericar-dial effusion. However, in a patient who can be demonstrated to have previously had normal cardiac function, it may be used to exclude segmental wall motion abnormalities that may suggest ischemia.The remaining workup should attempt to determine the underlying cause of the pericarditis and should be directed by the history and physical. Most inflammatory markers and labo-ratory tests are nonspecific, but C-reactive protein may be useful in predicting recurrence risks and in guiding the duration of