title: Atrial fibrillation

text: The primary pathologic change seen in atrial fibrillation is the progressive fibrosis of the atria. This fibrosis is due primarily to atrial dilation; however, genetic causes and inflammation may be factors in some individuals. Dilation of the atria can be due to almost any structural abnormality of the heart that can cause a rise in the pressure within the heart. This includes valvular heart disease (such as mitral stenosis, mitral regurgitation, and tricuspid regurgitation), hypertension, and congestive heart failure. Any inflammatory state that affects the heart can cause fibrosis of the atria. This is typically due to sarcoidosis but may also be due to autoimmune disorders that create autoantibodies against myosin heavy chains. Mutation of the "lamin AC" gene is also associated with fibrosis of the atria that can lead to atrial fibrillation.


title: Atrial fibrillation

text: Once dilation of the atria has occurred, this begins a chain of events that leads to the activation of the renin–angiotensin–aldosterone system (RAAS) and subsequent increase in the matrix metalloproteinases and disintegrin, which leads to atrial remodeling and fibrosis, with loss of atrial muscle mass. This process occurs gradually, and experimental studies have revealed patchy atrial fibrosis may precede the occurrence of atrial fibrillation and may progress with prolonged durations of atrial fibrillation.


title: Atrial fibrillation

text: Fibrosis is not limited to the muscle mass of the atria and may occur in the sinus node (SA node) and atrioventricular node (AV node), correlating with sick sinus syndrome. Prolonged episodes of atrial fibrillation have been shown to correlate with prolongation of the sinus node recovery time; this suggests that dysfunction of the SA node is progressive with prolonged episodes of atrial fibrillation.


title: Atrial fibrillation

text: Along with fibrosis, alterations in the atria that predispose to atrial fibrillation affect their electrical properties, as well as their responsiveness to the autonomic nervous system. The atrial remodeling that includes the pathologic changes described above has been referred to as "atrial myopathy".


title: Atrial fibrillation

text: There are multiple theories about the cause of atrial fibrillation. An important theory is that the regular impulses produced by the sinus node for a normal heartbeat are overwhelmed by rapid electrical discharges produced in the atria and adjacent parts of the pulmonary veins. Sources of these disturbances are either automatic foci, often localized at one of the pulmonary veins, or a small number of localized sources in the form of either a re-entrant leading circle or electrical spiral waves (rotors); these localized sources may be in the left atrium near the pulmonary veins or in a variety of other locations through both the left or right atrium. Three fundamental components favor the establishment of a leading circle or a rotor: slow conduction velocity of the cardiac action potential, a short refractory period, and a small wavelength. Meanwhile, the wavelength is the product of velocity and refractory period. If the action potential has fast conduction, with a long refractory period and/or conduction pathway shorter than the wavelength, an AF focus would not be established. In multiple wavelet theory, a wavefront will break into smaller daughter wavelets when encountering an obstacle, through a process called vortex shedding. But, under the proper conditions, such wavelets can reform and spin around a center, forming an AF focus.


title: Atrial fibrillation

text: In a heart with AF, the increased calcium release from the sarcoplasmic reticulum and increased calcium sensitivity can lead to an accumulation of intracellular calcium and causes downregulation of L-type calcium channels. This reduces the duration of action potential and the refractory period, thus favoring the conduction of re-entrant waves. Increased expression of inward-rectifier potassium ion channels can cause a reduced atrial refractory period and wavelength. The abnormal distribution of gap junction proteins such as GJA1 (also known as Connexin 43), and GJA5 (Connexin 40) causes non-uniformity of electrical conduction, thus causing the arrhythmia.


title: Atrial fibrillation

text: AF can be distinguished from atrial flutter (AFL), which appears as an organized electrical circuit usually in the right atrium. AFL produces characteristic saw-toothed F-waves of constant amplitude and frequency on an ECG, whereas AF does not. In AFL, the discharges circulate rapidly at a rate of 300 beats per minute (bpm) around the atrium. In AF, there is no such regularity, except at the sources where the local activation rate can exceed 500 bpm. Although AF and atrial flutter are distinct arrhythmias, atrial flutter may degenerate into AF, and an individual may experience both arrhythmias at different times.


title: Atrial fibrillation

text: Although the electrical impulses of AF occur at a high rate, most of them do not result in a heartbeat. A heartbeat results when an electrical impulse from the atria passes through the atrioventricular (AV) node to the ventricles and causes them to contract. During AF, if all of the impulses from the atria passed through the AV node, there would be severe ventricular tachycardia, resulting in a severe reduction of cardiac output. This dangerous situation is prevented by the AV node since its limited conduction velocity reduces the rate at which impulses reach the ventricles during AF.


title: Atrial fibrillation

text: The evaluation of atrial fibrillation involves a determination of the cause of the arrhythmia, and classification of the arrhythmia. Diagnostic investigation of AF typically includes a complete history and physical examination, ECG, transthoracic echocardiogram, complete blood count, and serum thyroid stimulating hormone level.


title: Atrial fibrillation

text: Numerous guidelines recommend opportunistic screening for atrial fibrillation in those 65 years and older. These organizations include the:


title: Atrial fibrillation

text: Single timepoint screening detects undiagnosed AF, which is often asymptomatic, in approximately 1.4% of people in this age group. A Scottish inquiry into atrial fibrillation estimated that as many as one-third of people with AF are undiagnosed. Despite this, in 2018, the United States Preventive Services Task Force found insufficient evidence to determine the usefulness of routine screening.


title: Atrial fibrillation

text: Given the importance of having a pathway to treatment, general practice is potentially an ideal setting to conduct AF screening. General practice was identified as a 'preferred' setting for AF screening by the AF-SCREEN international collaboration report due to the availability of nursing support and the natural pathway to treatment.


title: Atrial fibrillation

text: Screening in primary care has been trialled in a number of countries. These include: a recent Canadian study conducted in 184 general practices; a screening program conducted alongside influenza vaccinations in 10 Dutch practices; and several Australian studies showed that opportunistic screening in primary care by GPs and nurses using eHealth tools was feasible.


title: Atrial fibrillation

text: In general, the minimal evaluation of atrial fibrillation should be performed in all individuals with AF. The goal of this evaluation is to determine the general treatment regimen for the individual. If the results of the general evaluation warrant it, further studies may then be performed.


title: Atrial fibrillation

text: The history of the individual's atrial fibrillation episodes is probably the most important part of the evaluation. Distinctions should be made between those who are entirely asymptomatic when they are in AF (in which case the AF is found as an incidental finding on an ECG or physical examination) and those who have gross and obvious symptoms due to AF and can pinpoint whenever they go into AF or revert to sinus rhythm.


title: Atrial fibrillation

text: While many cases of AF have no definite cause, it may be the result of various other problems. Hence, kidney function and electrolytes are routinely determined, as well as thyroid-stimulating hormone (commonly suppressed in hyperthyroidism and of relevance if amiodarone is administered for treatment) and a blood count.


title: Atrial fibrillation

text: In acute-onset AF associated with chest pain, cardiac troponins, or other markers of damage to the heart muscle may be ordered. Coagulation studies (INR/aPTT) are usually performed, as anticoagulant medication may be commenced.


title: Atrial fibrillation

text: Atrial fibrillation is diagnosed on an electrocardiogram (ECG), an investigation performed routinely whenever an irregular heartbeat is suspected. Characteristic findings are the absence of P waves, with disorganized electrical activity in their place, and irregular R–R intervals due to irregular conduction of impulses to the ventricles. At very fast heart rates, atrial fibrillation may look more regular, which may make it more difficult to separate from other supraventricular tachycardias or ventricular tachycardia.


title: Atrial fibrillation

text: QRS complexes should be narrow, signifying that they are initiated by normal conduction of atrial electrical activity through the intraventricular conduction system. Wide QRS complexes are worrisome for ventricular tachycardia, although, in cases where there is a disease of the conduction system, wide complexes may be present in A-fib with a rapid ventricular response.


title: Atrial fibrillation

text: If paroxysmal AF is suspected, but an ECG during an office visit shows only a regular rhythm, AF episodes may be detected and documented with the use of ambulatory Holter monitoring (e.g., for a day). If the episodes are too infrequent to be detected by Holter monitoring with reasonable probability, then the person can be monitored for longer periods (e.g., a month) with an ambulatory event monitor.


title: Atrial fibrillation

text: In general, a non-invasive transthoracic echocardiogram (TTE) is performed in newly diagnosed AF, as well as if there is a major change in the person's clinical state. This ultrasound-based scan of the heart may help identify valvular heart disease (which may greatly increase the risk of stroke and alter recommendations for the appropriate type of anticoagulation), left and right atrial size (which predicts the likelihood that AF may become permanent), left ventricular size and function, peak right ventricular pressure (pulmonary hypertension), presence of left atrial thrombus (low sensitivity), presence of left ventricular hypertrophy and pericardial disease.


title: Atrial fibrillation

text: Significant enlargement of both the left and right atria is associated with long-standing atrial fibrillation and, if noted at the initial presentation of atrial fibrillation, suggests that the atrial fibrillation is likely to be of a longer duration than the individual's symptoms.


title: Atrial fibrillation

text: In general, an extended evaluation is not necessary for most individuals with atrial fibrillation and is performed only if abnormalities are noted in the limited evaluation, if a reversible cause of the atrial fibrillation is suggested, or if further evaluation may change the treatment course.


title: Atrial fibrillation

text: In general, a chest X-ray is performed only if a pulmonary cause of atrial fibrillation is suggested, or if other cardiac conditions are suspected (in particular congestive heart failure). This may reveal an underlying problem in the lungs or the blood vessels in the chest. In particular, if underlying pneumonia is suggested, then treatment of the pneumonia may cause the atrial fibrillation to terminate on its own.


title: Atrial fibrillation

text: A regular echocardiogram (transthoracic echo/TTE) has a low sensitivity for identifying blood clots in the heart. If this is suspected (e.g., when planning urgent electrical cardioversion), a transesophageal echocardiogram/TEE (or TOE where British spelling is used) is preferred.


title: Atrial fibrillation

text: The TEE has much better visualization of the left atrial appendage than transthoracic echocardiography. This structure, located in the left atrium, is the place where a blood clot forms in more than 90% of cases in non-valvular (or non-rheumatic) atrial fibrillation. TEE has a high sensitivity for locating thrombi in this area and can also detect sluggish blood flow in this area that is suggestive of blood clot formation.


title: Atrial fibrillation

text: If a blood clot is seen on TEE, then cardioversion is contraindicated due to the risk of stroke, and anticoagulation is recommended.


title: Atrial fibrillation

text: A Holter monitor is a wearable ambulatory heart monitor that continuously monitors the heart rate and heart rhythm for a short duration, typically 24 hours. In individuals with symptoms of significant shortness of breath with exertion or palpitations regularly, a Holter monitor may be of benefit to determine whether rapid heart rates (or unusually slow heart rates) during atrial fibrillation are the cause of the symptoms.


title: Atrial fibrillation

text: Some individuals with atrial fibrillation do well with normal activity but develop shortness of breath with exertion. It may be unclear whether the shortness of breath is due to a blunted heart rate response to exertion caused by excessive atrioventricular node-blocking agents, a very rapid heart rate during exertion, or other underlying conditions such as chronic lung disease or coronary ischemia. An exercise stress test will evaluate the individual's heart rate response to exertion and determine whether the AV node blocking agents are contributing to the symptoms.


title: Atrial fibrillation

text: The American College of Cardiology (ACC), American Heart Association (AHA), and the European Society of Cardiology (ESC) recommend in their guidelines the following classification system based on simplicity and clinical relevance.


title: Atrial fibrillation

text: All people with AF are initially in the category called "first detected AF". These people may or may not have had previous undetected episodes. If a first detected episode stops on its own in less than seven days and then another episode begins, later on, the category changes to "paroxysmal AF". Although people in this category have episodes lasting up to seven days, in most cases of paroxysmal AF, the episodes will stop in less than 24 hours. If the episode lasts for more than seven days, it is unlikely to stop on its own and is then known as "persistent AF". In this case, cardioversion can be attempted to restore a normal rhythm. If an episode continues for a year or more, the rhythm is then known as "longstanding persistent AF". If a decision is made by the person and their medical team to accept persistent AF and not attempt restoration of a normal sinus rhythm but instead manage the AF by simply controlling the person's ventricular rate then the rhythm is referred to as "permanent AF". As a further subtype, AF that is detected only by an implanted or wearable cardiac monitor is known as s"ubclinical AF."


title: Atrial fibrillation

text: Episodes that last less than 30 seconds are not considered in this classification system. Also, this system does not apply to cases where the AF is a secondary condition that occurs in the setting of a primary condition that may be the cause of the AF.


title: Atrial fibrillation

text: About half of people with AF have permanent AF, while a quarter have paroxysmal AF, and a quarter have persistent AF.


title: Atrial fibrillation

text: In addition to the above AF categories, which are mainly defined by episode timing and termination, the ACC/AHA/ESC guidelines describe additional AF categories in terms of other characteristics of the person. "Valvular AF" refers to AF attributable to moderate to severe mitral valve stenosis or atrial fibrillation in the presence of a mechanical artificial heart valve. This distinction may be useful as it has implications on appropriate treatment, including differing recommendations for anticoagulation, but the most recent guidelines discourage use of this term as it may be confusing. Other historically used definitions include "lone AF" – AF occurring in those aged under 60 in the absence of other cardiovascular or respiratory diseases. This description is also discouraged as it is recognised that AF always has an underlying cause. S"econdary AF" refers to AF that occurs in the setting of another condition that have caused the AF, such as acute myocardial infarction, cardiac surgery, pericarditis, myocarditis, hyperthyroidism, pulmonary embolism, pneumonia, or another acute pulmonary disease.


title: Atrial fibrillation

text: Prevention of atrial fibrillation focuses primarily on preventing or controlling its risk factors. Many of its risk factors, such as obesity, smoking, lack of physical activity, and excessive alcohol consumption, are modifiable and preventable with lifestyle modification or can be managed by a healthcare professional.


title: Atrial fibrillation

text: Several healthy lifestyle behaviors are associated with a lower likelihood of developing atrial fibrillation. Accordingly, consensus guidelines recommend abstaining from alcohol and recreational drugs, stopping tobacco use, maintaining a healthy weight, and regularly participating in moderate-intensity physical activities. Consistent moderate-intensity aerobic exercise, defined as achieving 3.0-5.9 METs of intensity, for at least 150 minutes per week may reduce the risk of developing new-onset atrial fibrillation. Few studies have examined the role of specific dietary changes and how it relates to the prevention of atrial fibrillation.


title: Atrial fibrillation

text: The main goals of treatment are to prevent circulatory instability and stroke. Rate or rhythm control is used to achieve the former, whereas anticoagulation is used to decrease the risk of the latter. If cardiovascularly unstable due to uncontrolled tachycardia, immediate cardioversion is indicated. Many antiarrhythmics, when used long term, increase the risk of death without any meaningful benefit. An integrated management approach, which includes stroke prevention, symptoms control and management of associated comorbidities was associated with better outcomes in patients with atrial fibrillation.


title: Atrial fibrillation

text: Regular aerobic exercise improves atrial fibrillation symptoms and AF-related quality of life. The effect of high-intensity interval training on reducing atrial fibrillation burden is unclear. Weight loss of at least 10% is associated with reduced atrial fibrillation burden in people who are overweight or obese.


title: Atrial fibrillation

text: For people who have both atrial fibrillation and obstructive sleep apnea, observational studies suggest that continuous positive airway pressure (CPAP) treatment appears to lower the risk of atrial fibrillation recurrence after undergoing ablation. Randomized controlled trials examining the role of obstructive sleep apnea treatment on atrial fibrillation incidence and burden are lacking. Guideline-recommended lifestyle and medical interventions are recommended for people with atrial fibrillation and coexisting conditions such as hyperlipidemia, diabetes mellitus, or hypertension without specific blood sugar or blood pressure targets for people with atrial fibrillation. Bariatric surgery may reduce the risk of new-onset atrial fibrillation in people with obesity without AF and may reduce the risk of a recurrence of AF after an ablation procedure in people with coexisting obesity and atrial fibrillation. It is important for all people with atrial fibrillation to optimize the control of all coexisting medical conditions that can worsen their atrial fibrillation, such as hyperthyroidism, diabetes, congestive heart failure, high blood pressure, chronic obstructive pulmonary disease, stimulant use (e.g., methamphetamine dependence), and excessive alcohol consumption.


title: Atrial fibrillation

text: Anticoagulation can be used to reduce the risk of stroke from AF. Anticoagulation is recommended in most people other than those at low risk of stroke or those at high risk of bleeding. The risk of falls and consequent bleeding in frail elderly people should not be considered a barrier to initiating or continuing anticoagulation since the risk of fall-related brain bleeding is low and the benefit of stroke prevention often outweighs the risk of bleeding. Similarly, the presence or absence of AF symptoms does not determine whether a person warrants anticoagulation and is not an indicator of stroke risk. Oral anticoagulation is underused in atrial fibrillation, while aspirin is overused in many who should be treated with a direct oral anticoagulant (DOAC) or warfarin. In 2019, DOACs were often recommended over warfarin by the American Heart Association.


title: Atrial fibrillation

text: The risk of stroke from non-valvular AF can be estimated using the CHADS-VASc score. In the 2019 AHA/ACC/HRS guidelines anticoagulation is recommended in non-valvular AF if there is a score of two or more in men and three or more in women and may be considered if there is a score of one in men or two in women; not using anticoagulation is reasonable if there is a score of zero in men or one in women. Guidelines from the American College of Chest Physicians, Asia-Pacific Heart Rhythm Society, Canadian Cardiovascular Society, European Society of Cardiology, Japanese Circulation Society, Korean Heart Rhythm Society, and the National Institute for Health and Care Excellence recommend the use of novel oral anticoagulants or warfarin with a CHADS-VASc score of one over aspirin and some directly recommend against aspirin. Experts generally advocate for most people with atrial fibrillation with CHADS-VASc scores of one or more receiving anticoagulation though aspirin is sometimes used for people with a score of one (moderate risk for stroke). There is little evidence to support the idea that the use of aspirin significantly reduces the risk of stroke in people with atrial fibrillation. Furthermore, aspirin's major bleeding risk (including bleeding in the brain) is similar to that of warfarin and DOACs despite its inferior efficacy.


title: Atrial fibrillation

text: Anticoagulation can be achieved through several means including warfarin, heparin, dabigatran, rivaroxaban, edoxaban, and apixaban. Many issues should be considered related to their comparative effectiveness, including the cost of DOACs, risk of stroke, risk of falls, comorbidities (such as chronic liver or kidney disease), the presence of significant mitral stenosis or mechanical heart valves, compliance, and speed of the desired onset of anticoagulation. The optimal approach to anticoagulation in people with AF and who simultaneously have other diseases (e.g., cirrhosis and end-stage kidney disease on dialysis) that predispose a person to both bleeding and clotting complications is unclear.


title: Atrial fibrillation

text: For those with non-valvular atrial fibrillation, DOACs are at least as effective as warfarin for preventing strokes and blood clots embolizing to the systemic circulation (if not more so) and are generally preferred over warfarin. DOACs carry a lower risk of bleeding in the brain compared to warfarin, although dabigatran is associated with a higher risk of intestinal bleeding. Dual antiplatelet therapy with aspirin and clopidogrel is inferior to warfarin for preventing strokes and has comparable bleeding risk in people with atrial fibrillation. In those who are also on aspirin, however, DOACs appear to be better than warfarin.


title: Atrial fibrillation

text: Warfarin is the recommended anticoagulant choice for persons with valvular atrial fibrillation (atrial fibrillation in the presence of a mechanical heart valve and/or moderate-severe mitral valve stenosis). The exception to this recommendation is in people with valvular atrial fibrillation who are unable to maintain a therapeutic INR on warfarin therapy; in such cases, treatment with a DOAC is then recommended.


title: Atrial fibrillation

text: There are two ways to approach atrial fibrillation using medications: rate control and rhythm control. Both methods have similar outcomes. "Rate control" lowers the heart rate closer to normal, usually 60 to 100 bpm, without trying to convert to a regular rhythm. "Rhythm control" tries to restore a normal heart rhythm in a process called cardioversion and maintains the normal rhythm with medications. Studies suggest that rhythm control is more important in the acute setting AF, whereas rate control is more important in the chronic phase.


title: Atrial fibrillation

text: The risk of stroke appears to be lower with rate control versus attempted rhythm control, at least in those with heart failure. AF is associated with a reduced quality of life, and, while some studies indicate that rhythm control leads to a higher quality of life, some did not find a difference.


title: Atrial fibrillation

text: Neither rate nor rhythm control is superior in people with heart failure when they are compared in various clinical trials. However, rate control is recommended as the first-line treatment regimen for people with heart failure. On the other hand, rhythm control is only recommended when people experience persistent symptoms despite adequate rate control therapy.


title: Atrial fibrillation

text: In those with a fast ventricular response, intravenous magnesium significantly increases the chances of achieving successful rate and rhythm control in the urgent setting without major side-effects. A person with poor vital signs, mental status changes, preexcitation, or chest pain often will go to immediate treatment with synchronized DC cardioversion. Otherwise, the decision of rate control versus rhythm control using medications is made. This is based on several criteria that include whether or not symptoms persist with rate control.


title: Atrial fibrillation

text: Rate control to a target heart rate of fewer than 110 beats per minute is recommended in most people. Lower heart rates may be recommended in those with left ventricular hypertrophy or reduced left ventricular function. Rate control is achieved with medications that work by increasing the degree of the block at the level of the AV node, decreasing the number of impulses that conduct into the ventricles. This can be done with:


title: Atrial fibrillation

text: In addition to these agents, amiodarone has some AV node blocking effects (in particular when administered intravenously) and can be used in individuals when other agents are contraindicated or ineffective (particularly due to hypotension).


title: Atrial fibrillation

text: Cardioversion is the attempt to switch an irregular heartbeat to a normal heartbeat using electrical or chemical means.


title: Atrial fibrillation

text: After successful cardioversion, the heart may be stunned, which means that there is a normal rhythm, but the restoration of normal atrial contraction has not yet occurred.


title: Atrial fibrillation

text: Catheter ablation (CA) is a procedure performed by an electrophysiologist, a cardiologist who specializes in heart rhythm problems, to restore the heart's normal rhythm by destroying, or electrically isolating, specific parts of the atria. A group of cardiologists led by Dr Haïssaguerre from noted in 1998 that the pulmonary veins are an important source of ectopic beats, initiating frequent paroxysms of atrial fibrillation, with these foci responding to treatment with radio-frequency ablation. Most commonly, CA electrically isolates the left atrium from the pulmonary veins, where most of the abnormal electrical activity promoting atrial fibrillation originates. CA is a form of rhythm control that restores normal sinus rhythm and reduces AF-associated symptoms more reliably than antiarrhythmic medications. Electrophysiologists generally use two forms of catheter ablation—radiofrequency ablation, or cryoablation. In young people with little-to-no structural heart disease where rhythm control is desired and cannot be maintained by medication or cardioversion, radiofrequency catheter ablation or cryoablation may be attempted and may be preferred over several years of medical therapy. Although radiofrequency ablation has become an accepted intervention in selected younger people and may be more effective than medication at improving symptoms and quality of life, there is no evidence that ablation reduces all-cause mortality, stroke, or heart failure. Some evidence indicates CA may be particularly helpful for people with AF who also have heart failure. AF may recur in people who have undergone CA and nearly half of people who undergo it will require a repeat procedure to achieve long-term control of their AF. In general, CA is more successful at preventing AF recurrence if AF is paroxysmal as opposed to persistent . As CA does not reduce the risk of stroke, many are advised to continue their anticoagulation. Possible complications include common, minor complications such as the formation of a collection of blood at the site where the catheter goes into the vein (access site hematoma), but also more dangerous complications including bleeding around the heart (cardiac tamponade), stroke, damage to the esophagus (atrio-esophageal fistula), or even death.


title: Atrial fibrillation

text: An alternative to catheter ablation is surgical ablation. The Maze procedure, first performed in 1987, is an effective invasive surgical treatment that is designed to create electrical blocks or barriers in the atria of the heart. The idea is to force abnormal electrical signals to move along one, uniform path to the lower chambers of the heart (ventricles), thus restoring the normal heart rhythm. People with AF often undergo cardiac surgery for other underlying reasons and are frequently offered concomitant AF surgery to reduce the frequency of short- and long-term AF. Concomitant AF surgery is more likely to lead to the person being free from atrial fibrillation and off medications three months after surgery, but these people are also more likely to need a pacemaker following the procedure.


title: Atrial fibrillation

text: AF often occurs after cardiac surgery and is usually self-limiting. It is strongly associated with age, preoperative hypertension, and the number of vessels grafted. Measures should be taken to control hypertension preoperatively to reduce the risk of AF. Also, people with a higher risk of AF, e.g., people with pre-operative hypertension, more than three vessels grafted, or greater than 70 years of age, should be considered for prophylactic treatment. Postoperative pericardial effusion is also suspected to be the cause of atrial fibrillation. Prophylaxis may include prophylactic postoperative rate and rhythm management. Some authors perform posterior pericardiotomy to reduce the incidence of postoperative AF. When AF occurs, management should primarily be rate and rhythm control. However, cardioversion may be used if the patient is hemodynamically unstable, highly symptomatic, or AF persists for six weeks after discharge. In persistent cases, anticoagulation should be used.


title: Atrial fibrillation

text: There is growing evidence that left atrial appendage occlusion therapy may reduce the risk of stroke in people with non-valvular AF as much as warfarin.


title: Atrial fibrillation

text: After catheter ablation, people are moved to a cardiac recovery unit, intensive care unit, or cardiovascular intensive care unit where they are not allowed to move for 46 hours. Minimizing movement helps prevent bleeding from the site of the catheter insertion. The length of time people stay in the hospital varies from hours to days. This depends on the problem, the length of the operation, and whether or not general anesthetic was used. Additionally, people should not engage in strenuous physical activityto maintain a low heart rate and low blood pressurefor around six weeks.


title: Atrial fibrillation

text: Atrial fibrillation increases the risk of heart failure by 11 per 1000, kidney problems by 6 per 1000, death by 4 per 1000, stroke by 3 per 1000, and coronary heart disease by 1 per 1000. Women have a worse outcome overall than men. Evidence increasingly suggests that atrial fibrillation is independently associated with a higher risk of developing dementia.


title: Atrial fibrillation

text: Among Danish men aged 50, with no risk factors, the 5-year risk of stroke was 1.1% and with AF alone 2.5%. For women the risks were slightly less, 0.7% and 2.1%. For men aged 70, the 5-year risk of stroke was 4.8% and with AF alone 6.8%. For women aged 70 the risk was again lower than for men, 3.4% with no added risk factor and 8.2% with AF.


title: Atrial fibrillation

text: Determining the risk of an embolism causing a stroke is important for guiding the use of anticoagulants. The most accurate clinical prediction rules are:


title: Atrial fibrillation

text: Both the CHADS and the CHADS-VASc score predict future stroke risk in people with A-fib with CHADS-VASc score being more accurate. Some that had a CHADS score of zero had a CHADS-VASc score of three, with a 3.2% annual risk of stroke. Thus, a CHADS-VASc score of zero is considered very low risk.


title: Atrial fibrillation

text: In atrial fibrillation, the lack of an organized atrial contraction can result in some stagnant blood in the left atrium (LA) or left atrial appendage (LAA). This lack of movement of blood can lead to thrombus formation (blood clotting). If the clot becomes mobile and is carried away by the blood circulation, it is called an embolus. An embolus proceeds through smaller and smaller arteries until it plugs one of them and prevents blood from flowing through the artery. This process results in end organ damage due to the loss of nutrients, oxygen, and the removal of cellular waste products. Emboli in the brain may result in an ischemic stroke or a transient ischemic attack (TIA).


title: Atrial fibrillation

text: More than 90% of cases of thrombi associated with non-valvular atrial fibrillation evolve in the left atrial appendage. However, the LAA lies in close relation to the free wall of the left ventricle, and thus the LAA's emptying and filling, which determines its degree of blood stagnation, may be helped by the motion of the wall of the left ventricle if there is good ventricular function.


title: Atrial fibrillation

text: Atrial fibrillation has been independently associated with a higher risk of developing cognitive impairment, vascular dementia, and Alzheimer disease and with elevated levels of neurofilament light chain in blood, a biomarker indicating neuroaxonal injury. Several mechanisms for this association have been proposed, including silent small blood clots (subclinical microthrombi) traveling to the brain resulting in small ischemic strokes without symptoms, altered blood flow to the brain, inflammation, clinically silent small bleeds in the brain, and genetic factors. Tentative evidence suggests that effective anticoagulation with direct oral anticoagulants or warfarin may be somewhat protective against AF-associated dementia and evidence of silent ischemic strokes on MRI but this remains an active area of investigation.


title: Atrial fibrillation

text: Atrial fibrillation is the most common arrhythmia and affects more than 33 million people worldwide. In Europe and North America, , it affects about 2% to 3% of the population. This is an increase from 0.4 to 1% of the population around 2005. In the developing world, rates are about 0.6% for males and 0.4% for females. The number of people diagnosed with AF has increased due to better detection of silent AF and increasing age and conditions that predispose to it.


title: Atrial fibrillation

text: It also accounts for one-third of hospital admissions for cardiac rhythm disturbances, and the rate of admissions for AF has risen in recent years. AF is the cause for 20% to 30% of all ischemic strokes. After a transient ischemic attack or stroke, about 11% are found to have a new diagnosis of atrial fibrillation. 3% to 11% of patients with AF have structurally normal hearts. Approximately 2.2 million individuals in the United States and 4.5 million in the European Union have AF.


title: Atrial fibrillation

text: The number of new cases each year of AF increases with age. In people older than 80 years, it affects about 8%. In contrast, in younger people the prevalence is estimated to be 0.05% and is associated with congenital heart disease or structural heart disease in this demographic. As of 2001, it was anticipated that in developed countries, the number of people with atrial fibrillation was likely to increase during the following 50 years, due to the growing proportion of elderly people.


title: Atrial fibrillation

text: Atrial fibrillation is more common in men than in women when reviewed in European and North American populations. In developed and developing countries, there is also a higher rate in men than in women. The risk factors associated with AF are also distributed differently according to sex. In men, coronary disease is more frequent, while in women, high systolic blood pressure and valvular heart disease are more prevalent.


title: Atrial fibrillation

text: Rates of AF are lower in populations of African descent than in populations of European descent. African descent is associated with a protective effect for AF, due to the lower presence of SNPs with guanine alleles. European ancestry has more frequent mutations. The variant rs4611994 for the gene PITX2 is associated with risk of AF in African and European populations. Hispanic and Asian populations have a lower risk of AF than European populations. The risk of AF in non-European populations is associated with characteristic risk factors of these populations, such as hypertension.


title: Atrial fibrillation

text: Atrial fibrillation is an uncommon condition in children but sometimes occurs in association with certain inherited and acquired conditions. Congenital heart disease and rheumatic fever are the most common causes of atrial fibrillation in children. Other inherited heart conditions associated with the development of atrial fibrillation in children include Brugada syndrome, short QT syndrome, Wolff Parkinson White syndrome, and other forms of supraventricular tachycardia (e.g., AV nodal reentrant tachycardia). Adults who survived congenital heart disease have an increased risk of developing AF. In particular, people who had atrial septal defects, Tetralogy of Fallot, or Ebstein's anomaly, and those who underwent the Fontan procedure, are at higher risk with prevalence rates of up to 30% depending on the heart's anatomy and the person's age.


title: Atrial fibrillation

text: Because the diagnosis of atrial fibrillation requires measurement of the electrical activity of the heart, atrial fibrillation was not truly described until 1874, when Edmé Félix Alfred Vulpian observed the irregular atrial electrical behavior that he termed ""fremissement fibrillaire"" in dog hearts. In the mid-18th century, Jean-Baptiste de Sénac made note of dilated, irritated atria in people with mitral stenosis. The irregular pulse associated with AF was first recorded in 1876 by Carl Wilhelm Hermann Nothnagel and termed ""delirium cordis"", stating that "[I]n this form of arrhythmia the heartbeats follow each other in complete irregularity. At the same time, the height and tension of the individual pulse waves are continuously changing". Correlation of delirium cordis with the loss of atrial contraction, as reflected in the loss of "a waves" in the jugular venous pulse, was made by Sir James MacKenzie in 1904. Willem Einthoven published the first ECG showing AF in 1906. The connection between the anatomic and electrical manifestations of AF and the irregular pulse of delirium cordis was made in 1909 by Carl Julius Rothberger, Heinrich Winterberg, and Sir Thomas Lewis.


title: Atrial fibrillation

text: Atrial fibrillation occurs in other animals, including cats, dogs, and horses. Unlike humans, dogs rarely develop the complications that stem from blood clots breaking off from inside the heart and traveling through the arteries to distant sites (thromboembolic complications). Cats rarely develop atrial fibrillation but appear to have a higher risk of thromboembolic complications than dogs. Cats and dogs with atrial fibrillation often have underlying structural heart disease that predisposes them to the condition. The medications used in animals for atrial fibrillation are largely similar to those used in humans. Electrical cardioversion is occasionally performed in these animals, but the need for general anesthesia limits its use. Standardbred horses appear to be genetically susceptible to developing atrial fibrillation. Horses that develop atrial fibrillation often have minimal or no underlying heart disease, and the presence of atrial fibrillation in horses can adversely affect physical performance.


title: Hande Erçel

text: Hande Erçel (born 24 November 1993) is a Turkish actress, best known for Gunesin Kizlari, Ask Laftan Anlamaz, Halka and Sen Çal Kapimi.


title: Hande Erçel

text: Hande Erçel starred in the series "Aşk Laftan Anlamaz" (2016–2017) as Hayat Uzun, opposite Burak Deniz. The show gained her and Deniz wide popularity in India, Pakistan and Uzbekistán especially in Middle East. She also played the role of Hazal in "Siyah İnci" on Star TV. She then landed the role of Müjde in "Halka" on TRT 1. Her performances include the role of Azize Günay in "Azize", broadcast on Kanal D, opposite Buğra Gülsoy. In 2020, Erçel was cast in a leading role in "Sen Çal Kapımı" together with Kerem Bürsin, which opened with high ratings in Turkey. It was also sold to more than 100 countries, with Spain becoming the first country in the world besides Turkey to air the series.


title: Jägermeister

text: Wilhelm Mast was a vinegar manufacturer and wine-trader in the city of Wolfenbüttel, Germany. His son, Curt Mast (1897–1970), was passionate about the production of spirits and liqueurs, and always keen to help his father in the business even at an early age. In 1934, at the age of 37, after he took over his father's business, Curt devised the recipe for "Jägermeister".


title: Jägermeister

text: Curt was an enthusiastic hunter. The name "Jägermeister" in German literally means "Master Hunter", "Hunt Master" or "master of the hunt". It is a title for a high-ranking official in charge of matters related to hunting and gamekeeping. The term ' had existed as a job title for many centuries. In 1934 the new ' (Reich Hunting Law) re-defined the term, applying it to senior foresters, game wardens, and gamekeepers in the German civil service. was appointed ' (Reich Hunting Master) when the new hunting law was introduced. Thus, when Jägermeister was introduced in 1935, its name was already familiar to Germans, who sometimes called the product "".


title: Jägermeister

text: is a type of liqueur called (herbal liqueur). It is akin to other European liqueurs, such as from Denmark, balsam and from Moldova, from the Netherlands, from Hungary, from the Czech Republic, Gorzka Żołądkowa from Poland, from Slovakia, from Croatia, Riga Black Balsam from Latvia, from Serbia, from Italy, Licor Beirão from Portugal and and from France. In contrast to those beverages, has a sweeter taste. In Germany itself, there are quite a few competitors, such as , , , , , and , some of which are as sweet as Jägermeister.


title: Jägermeister

text: 's ingredients include 56 herbs, fruits, roots, and spices, including citrus peel, licorice, anise, poppy seeds, saffron, ginger, juniper berries, and ginseng. These ingredients are ground, then steeped in water and alcohol for two to three days. This mixture is filtered and stored in oak barrels for about a year. Then the liqueur is filtered again, and mixed with sugar, caramel and alcohol.


title: Jägermeister

text: The company recommends that be kept on ice and served cold, and suggests that it be kept in a freezer at −18 °C (0 °F) or on tap between .


title: Jägermeister

text: The label on Jägermeister bottles features a glowing Christian cross seen between the antlers of a stag. This image is a reference to the two Christian patron saints of hunters, Saint Hubertus and Saint Eustace, both of whom converted to Christianity after experiencing a vision in which they saw a Christian cross between the antlers of a stag.


title: Jägermeister

text: In the product name on the label is one of the few surviving examples of the use of the long s in print.


title: Jägermeister

text: The label contains the following verse from the poem "", by the forester, hunter, and ornithologist ; von Riesenthal is not credited on the label.


title: Jägermeister

text: In 2012 launched premixed drinks as a brand extension. The drinks come in two flavours, "raw" and "ginger lime".


title: Jägermeister

text: In 2018 launched a premium line extension titled Manifest. The 38% ABV spirit is twice oak-aged and not to be served ice cold.


title: Jägermeister

text: In 2019 launched the first of its karakter series, Scharf, also known as "Hot Ginger." Each extension in the "karakter" series was intended to highlight one of 's 56 signature herbs and spices. As of January 2021 no further extensions under the "karakter" series have been announced.


title: Jägermeister

text: In 2019 launched Cold Brew Coffee Liqueur, using its original recipe with fair trade coffee and cacao added.


title: Jägermeister

text: From the 1970s, the brand has developed an association with motor racing, as they have sponsored various European racing teams, primarily those who fielded BMWs and Porsches. These teams have competed in various major racing series including Formula One (March and EuroBrun), DRM (Max Moritz, Kremer, Zakspeed), DTM and Group C (Brun Motorsport), who took the team title in the 1986 World Sportscar Championship.


title: Jägermeister

text: 's orange livery is one of the more commonly recognised in motorsport. The Spanish Fly slot car brand has recently brought out model cars with the distinctive design. More recently, they introduced the Naylor Racing NHRA Pro Stock car, minus its signature orange livery. An article in the January 31, 2008, edition of "Autosport" listed the livery as one of the twenty most iconic commercial colour schemes.


title: Jägermeister

text: As of 2018 Jägermeister has sponsored the National Hockey League (NHL) as the official shot of the NHL.


title: Jägermeister

text: In the United States, became popular through promotion by Sidney Frank and through its association with heavy metal and rock music bands such as Murphy's Law, Halestorm, Metallica, Mötley Crüe, Pantera, Slayer, HIM, Crossfaith, Epica, The Bloodhound Gang, Psychostick, and Turbonegro. was the tour sponsor of numerous bands of this genre.


title: Jägermeister

text: The Music Tour, which was owned by Sidney Frank Importing, was an event that was held each year in the spring and fall.


title: Jägermeister

text: In Australia, sponsors the AIR Charts, which are Australia's official independent music charts (run by the Australian Independent Record Labels Association).


title: Jägermeister

text: In 2020 USA launched a program titled "Meister Class," an initiative to provide emerging musicians with insight from and access to established stars Mustard, Smino, and EarthGang.


title: Jägermeister

text: On December 18, 2020 it was announced that USA donated one million dollars to NIVA Emergency Relief Fund in support of venues struggling due to COVID-19.


title: Ravi Shankar

text: Ravi Shankar (; born Robindro Shaunkor Chowdhury, sometimes spelled as Rabindra Shankar Chowdhury; 7 April 1920 – 11 December 2012) was an Indian sitarist and composer. A sitar virtuoso, he became the world's best-known export of North Indian classical music in the second half of the 20th century, and influenced many musicians in India and throughout the world. Shankar was awarded India's highest civilian honour, the Bharat Ratna, in 1999.


title: Ravi Shankar

text: Shankar was born to a Bengali Brahmin family in India, and spent his youth as a dancer touring India and Europe with the dance group of his brother Uday Shankar. He gave up dancing in 1938 to study sitar playing under court musician Allauddin Khan. After finishing his studies in 1944, Shankar worked as a composer, creating the music for the "Apu Trilogy" by Satyajit Ray, and was music director of All India Radio, New Delhi, from 1949 to 1956.


title: Ravi Shankar

text: In 1956, Shankar began to tour Europe and the Americas playing Indian classical music and increased its popularity there in the 1960s through teaching, performance, and his association with violinist Yehudi Menuhin and Beatles guitarist George Harrison. His influence on Harrison helped popularize the use of Indian instruments in Western pop music in the latter half of the 1960s. Shankar engaged Western music by writing compositions for sitar and orchestra, and toured the world in the 1970s and 1980s. From 1986 to 1992, he served as a nominated member of Rajya Sabha, the upper chamber of the Parliament of India. He continued to perform until the end of his life.


title: Ravi Shankar

text: Shankar was born on 7 April 1920 in Benares (now Varanasi), then the capital of the eponymous princely state, in a Bengali family, as the youngest of seven brothers. His father, Shyam Shankar Chowdhury, was a Middle Temple barrister and scholar from East Bengal (now Bangladesh). A respected statesman, lawyer and politician, he served for several years as "dewan" (Prime minister) of Jhalawar, Rajasthan, and used the Sanskrit spelling of the family name and removed its last part. Shyam was married to Hemangini Devi who hailed from a small village named Nasrathpur in Mardah block of Ghazipur district, near Benares and her father was a prosperous landlord. Shyam later worked as a lawyer in London, England, and there he married a second time while Devi raised Shankar in Benares, and did not meet his son until he was eight years old.


title: Ravi Shankar

text: Shankar shortened the Sanskrit version of his first name, Ravindra, to Ravi, for "sun". Shankar had five siblings: Uday (who became a famous choreographer and dancer), Rajendra, Debendra and Bhupendra. Shankar attended the Bengalitola High School in Benares between 1927 and 1928.


title: Ravi Shankar

text: At the age of 10, after spending his first decade in Benares, Shankar went to Paris with the dance group of his brother, choreographer Uday Shankar. By the age of 13 he had become a member of the group, accompanied its members on tour and learned to dance and play various Indian instruments. Uday's dance group travelled Europe and the United States in the early to mid-1930s and Shankar learned French, discovered Western classical music, jazz, cinema and became acquainted with Western customs. Shankar heard Allauddin Khan – the lead musician at the court of the princely state of Maihar – play at a music conference in December 1934 in Calcutta, and Uday persuaded the Maharaja of Maihar H.H Maharaja Brijnath singh Judev in 1935 to allow Khan to become his group's soloist for a tour of Europe. Shankar was sporadically trained by Khan on tour, and Khan offered Shankar training to become a serious musician under the condition that he abandon touring and come to Maihar.


title: Ravi Shankar

text: Shankar's parents had died by the time he returned from the Europe tour, and touring the West had become difficult because of political conflicts that would lead to World War II. Shankar gave up his dancing career in 1938 to go to Maihar and study Indian classical music as Khan's pupil, living with his family in the traditional "gurukul" system. Khan was a rigorous teacher and Shankar had training on "sitar" and "surbahar", learned "ragas" and the musical styles "dhrupad", "dhamar", and "khyal", and was taught the techniques of the instruments "rudra veena", "rubab", and "sursingar". He often studied with Khan's children Ali Akbar Khan and Annapurna Devi. Shankar began to perform publicly on "sitar" in December 1939 and his debut performance was a "jugalbandi" (duet) with Ali Akbar Khan, who played the string instrument "sarod".


title: Ravi Shankar

text: Shankar completed his training in 1944. He moved to Mumbai and joined the Indian People's Theatre Association, for whom he composed music for ballets in 1945 and 1946. Shankar recomposed the music for the popular song "Sare Jahan Se Achcha" at the age of 25. He began to record music for HMV India and worked as a music director for All India Radio (AIR), New Delhi, from February 1949 until January 1956. Shankar founded the Indian National Orchestra at AIR and composed for it; in his compositions he combined Western and classical Indian instrumentation. Beginning in the mid-1950s he composed the music for the "Apu Trilogy" by Satyajit Ray, which became internationally acclaimed. He was music director for several Hindi movies including "Godaan" and "Anuradha".


title: Ravi Shankar

text: V. K. Narayana Menon, director of AIR Delhi, introduced the Western violinist Yehudi Menuhin to Shankar during Menuhin's first visit to India in 1952. Shankar had performed as part of a cultural delegation in the Soviet Union in 1954 and Menuhin invited Shankar in 1955 to perform in New York City for a demonstration of Indian classical music, sponsored by the Ford Foundation.


title: Ravi Shankar

text: Shankar heard about the positive response Khan received and resigned from AIR in 1956 to tour the United Kingdom, Germany, and the United States. He played for smaller audiences and educated them about Indian music, incorporating "ragas" from the South Indian Carnatic music in his performances, and recorded his first LP album "Three Ragas" in London, released in 1956. In 1958, Shankar participated in the celebrations of the 10th anniversary of the United Nations and UNESCO music festival in Paris. From 1961, he toured Europe, the United States, and Australia, and became the first Indian to compose music for non-Indian films. Shankar founded the Kinnara School of Music in Mumbai in 1962.


title: Ravi Shankar

text: Shankar befriended Richard Bock, founder of World Pacific Records, on his first American tour and recorded most of his albums in the 1950s and 1960s for Bock's label. The Byrds recorded at the same studio and heard Shankar's music, which led them to incorporate some of its elements in theirs, introducing the genre to their friend George Harrison of the Beatles.


title: Ravi Shankar

text: In 1967, Shankar performed a well-received set at the Monterey Pop Festival. While complimentary of the talents of several of the rock artists at the festival, he said he was "horrified" to see Jimi Hendrix set fire to his guitar on stage: "That was too much for me. In our culture, we have such respect for musical instruments, they are like part of God." Shankar's peaked at number 43 on "Billboard"s pop LPs chart in the US, which remains the highest placing he achieved on that chart.


title: Ravi Shankar

text: Shankar won a Grammy Award for Best Chamber Music Performance for "West Meets East", a collaboration with Yehudi Menuhin. He opened a Western branch of the Kinnara School of Music in Los Angeles, in May 1967, and published an autobiography, "My Music, My Life", in 1968. In 1968, he composed the score for the film "Charly".


title: Ravi Shankar

text: He performed at the Woodstock Festival in August 1969, and found he disliked the venue. In the late 1960s, Shankar distanced himself from the hippie movement and drug culture. He explained during an interview:


title: Ravi Shankar

text: In October 1970, Shankar became chair of the Department of Indian Music of the California Institute of the Arts after previously teaching at the City College of New York, the University of California, Los Angeles, and being guest lecturer at other colleges and universities, including the Ali Akbar College of Music. In late 1970, the London Symphony Orchestra invited Shankar to compose a concerto with "sitar". "Concerto for Sitar & Orchestra" was performed with André Previn as conductor and Shankar playing the "sitar". Shankar performed at the Concert for Bangladesh in August 1971, held at Madison Square Garden in New York. After the musicians had tuned up on stage for over a minute, the crowd of rock-music fans broke into applause, to which the amused Shankar responded, "If you like our tuning so much, I hope you will enjoy the playing more." which confused the audience. Although interest in Indian music had decreased in the early 1970s, the live album from the concert became one of the best-selling recordings to feature the genre and won Shankar a second Grammy Award.


title: Ravi Shankar

text: In November and December 1974, Shankar co-headlined a North American tour with George Harrison. The demanding schedule weakened his health, and he suffered a heart attack in Chicago, causing him to miss a portion of the tour. Harrison, Shankar and members of the touring band visited the White House on invitation of John Gardner Ford, son of US president Gerald Ford. Shankar toured and taught for the remainder of the 1970s and the 1980s and released his second concerto, "Raga Mala", conducted by Zubin Mehta, in 1981. Shankar was nominated for an Academy Award for Best Original Music Score for his work on the 1982 movie "Gandhi".


title: Ravi Shankar

text: He performed in Moscow in 1988, with 140 musicians, including the Russian Folk Ensemble and members of the Moscow Philharmonic, along with his own group of Indian musicians.


title: Ravi Shankar

text: He served as a member of the Rajya Sabha, the upper chamber of the Parliament of India, from 12 May 1986 to 11 May 1992, after being nominated by Indian Prime Minister Rajiv Gandhi. Shankar composed the dance drama "Ghanashyam" in 1989. His liberal views on musical co-operation led him to contemporary composer Philip Glass, with whom he released an album, "Passages", in 1990, in a project initiated by Peter Baumann of the band Tangerine Dream.


title: Ravi Shankar

text: Because of the positive response to Shankar's 1996 career compilation "", Shankar wrote a second autobiography, "Raga Mala". He performed between 25 and 40 concerts every year during the late 1990s. Shankar taught his daughter Anoushka Shankar to play "sitar" and in 1997 became a Regents' Professor at University of California, San Diego.


title: Ravi Shankar

text: He performed with Anoushka for the BBC in 1997 at the Symphony Hall in Birmingham, England. In the 2000s, he won a Grammy Award for Best World Music Album for "" and toured with Anoushka, who released a book about her father, "Bapi: Love of My Life", in 2002. After George Harrison's death in 2001, Shankar performed at the Concert for George, a celebration of Harrison's music staged at the Royal Albert Hall in London in 2002.


title: Ravi Shankar

text: In June 2008, Shankar played what was billed as his last European concert, but his 2011 tour included dates in the United Kingdom.


title: Ravi Shankar

text: On 1 July 2010, at the Southbank Centre's Royal Festival Hall, London, England, Anoushka Shankar, on sitar, performed with the London Philharmonic Orchestra, conducted by David Murphy, which was billed the first "Symphony" by Ravi Shankar.


title: Ravi Shankar

text: Beatles guitarist George Harrison, who was first introduced to Shankar's music by American singers Roger McGuinn and David Crosby, who were big fans of Shankar, became influenced by Shankar's music. He went on to help popularize Shankar and the use of Indian instruments in pop music throughout the 1960s. Olivia Harrison explains:


title: Ravi Shankar

text: Harrison became interested in Indian classical music, bought a sitar and used it to record the song "Norwegian Wood (This Bird Has Flown)". In 1968, he went to India to take lessons from Shankar, some of which were captured on film. This led to Indian music being used by other musicians and popularised the raga rock trend. As the sitar and Indian music grew in popularity, groups such as the Rolling Stones, the Animals and the Byrds began using it in some of their songs. The influence even extended to blues musicians such as Michael Bloomfield, who created a raga-influenced improvisation number, "East-West" (Bloomfield scholars have cited its working title as "The Raga" when Bloomfield and his collaborator Nick Gravenites began to develop the idea) for the Butterfield Blues Band in 1966.


title: Ravi Shankar

text: Harrison met Shankar in London in June 1966 and visited India later that year for six weeks to study "sitar" under Shankar in Srinagar. During the visit, a documentary film about Shankar named "Raga" was shot by Howard Worth and released in 1971. Shankar's association with Harrison greatly increased Shankar's popularity, and decades later Ken Hunt of AllMusic wrote that Shankar had become "the most famous Indian musician on the planet" by 1966.


title: Ravi Shankar

text: George Harrison organized the charity Concert for Bangladesh in August 1971, in which Shankar participated. During the 1970s, Shankar and Harrison worked together again, recording "Shankar Family & Friends" in 1973 and touring North America the following year to a mixed response after Shankar had toured Europe with the Harrison-sponsored Music Festival from India. Shankar wrote a second autobiography, "Raga Mala", with Harrison as editor.


title: Ravi Shankar

text: Shankar developed a style distinct from that of his contemporaries and incorporated influences from rhythm practices of Carnatic music. His performances begin with solo "alap", "jor", and "jhala" (introduction and performances with pulse and rapid pulse) influenced by the slow and serious "dhrupad" genre, followed by a section with "tabla" accompaniment featuring compositions associated with the prevalent "khyal" style. Shankar often closed his performances with a piece inspired by the light-classical "thumri" genre.


title: Ravi Shankar

text: Shankar has been considered one of the top "sitar" players of the second half of the 20th century. He popularised performing on the bass octave of the "sitar" for the "alap" section and became known for a distinctive playing style in the middle and high registers that used quick and short deviations of the playing string and his sound creation through stops and strikes on the main playing string. Narayana Menon of "The New Grove Dictionary" noted Shankar's fondness for rhythmic novelties, among them the use of unconventional rhythmic cycles. Hans Neuhoff of "Musik in Geschichte und Gegenwart" has argued that Shankar's playing style was not widely adopted and that he was surpassed by other "sitar" players in the performance of melodic passages. Shankar's interplay with Alla Rakha improved appreciation for "tabla" playing in Hindustani classical music. Shankar promoted the "jugalbandi" duet concert style. Shankar introduced at least 31 new ragas, including "Nat Bhairav", "Ahir Lalit", "Rasiya", "Yaman Manjh", "Gunji Kanhara", "Janasanmodini", "Tilak Shyam", "Bairagi", "Mohan Kauns", "Manamanjari", "Mishra Gara", "Pancham Se Gara", "Purvi Kalyan", "Kameshwari", "Gangeshwari", "Rangeshwari", "Parameshwari", "Palas Kafi", "Jogeshwari", "Charu Kauns", "Kaushik Todi", "Bairagi Todi", "Bhawani Bhairav", "Sanjh Kalyan", "Shailangi", "Suranjani", "Rajya Kalyan", "Banjara", "Piloo Banjara", "Suvarna", "Doga Kalyan", "Nanda Dhwani", and "Natacharuka (for Anoushka)". In 2011, at a concert recorded and released in 2012 as "Tenth Decade in Concert: Ravi Shankar Live in Escondido", Shankar introduced a new percussive sitar technique called "Goonga Sitar", whereby the strings are muffled with a cloth.


title: Ravi Shankar

text: Shankar married Allauddin Khan's daughter Annapurna Devi (Roshanara Khan) in 1941 and their son, Shubhendra Shankar, was born in 1942. He separated from Devi during 1962 and continued a relationship with Kamala Shastri, a dancer, that had begun in the late 1940s.


title: Ravi Shankar

text: An affair with Sue Jones, a New York concert producer, led to the birth of Norah Jones in 1979. He separated from Shastri in 1981 and lived with Jones until 1986.


title: Ravi Shankar

text: An affair with Sukanya Rajan, whom he had known since the 1970s, led to the birth of their daughter Anoushka Shankar in 1981. In 1989, he married Sukanya Rajan at Chilkur Temple in Hyderabad.


title: Ravi Shankar

text: Shankar's son, Shubhendra "Shubho" Shankar, often accompanied him on tours. He could play the "sitar" and "surbahar", but elected not to pursue a solo career. Shubhendra died of pneumonia in 1992.


title: Ravi Shankar

text: His daughter Norah Jones became a successful musician in the 2000s, winning eight Grammy Awards in 2003.


title: Ravi Shankar

text: His daughter Anoushka Shankar was nominated for a Grammy Award for Best World Music Album in 2003. Anoushka and her father were both nominated for Best World Music Album at the 2013 Grammy Awards for separate albums.


title: Ravi Shankar

text: Shankar was a Hindu, and a devotee of the Hindu god Hanuman. He was also an "ardent devotee" of the Bengali Hindu saint, Sri Anandamayi Ma. Shankar used to visit Anandamayi Ma frequently and performed for her on various occasions. Shankar wrote of his hometown, Benares (Varanasi), and his initial encounter with "Ma":


title: Ravi Shankar

text: Varanasi is the eternal abode of Lord Shiva, and one of my favorite temples is that of Lord Hanuman, the monkey god. The city is also where one of the miracles that have happened in my life took place: I met Ma Anandamayi, a great spiritual soul. Seeing the beauty of her face and mind, I became her ardent devotee. Sitting at home now in Encinitas, in Southern California, at the age of 88, surrounded by the beautiful greens, multi-colored flowers, blue sky, clean air, and the Pacific Ocean, I often reminisce about all the wonderful places I have seen in the world. I cherish the memories of Paris, New York, and a few other places. But Varanasi seems to be etched in my heart!


title: Ravi Shankar

text: Shankar was a vegetarian. He wore a large diamond ring which he said was "manifested" by Sathya Sai Baba. He lived with Sukanya in Encinitas, California.


title: Ravi Shankar

text: Shankar performed his final concert, with daughter Anoushka, on 4 November 2012 at the Terrace Theater in Long Beach, California.


title: Ravi Shankar

text: On 9 December 2012, Shankar was admitted to Scripps Memorial Hospital in La Jolla, San Diego, California after complaining of breathing difficulties. He died on 11 December 2012 at around 16:30 PST after undergoing heart valve replacement surgery.


title: Ravi Shankar

text: The "Swara Samrat festival", organized on 5–6 January 2013 and dedicated to Ravi Shankar and Ali Akbar Khan, included performances by such musicians as Shivkumar Sharma, Birju Maharaj, Hariprasad Chaurasia, Zakir Hussain, and Girija Devi.


title: Nintendo 64

text: The (N64) is a home video game console developed by Nintendo. The successor to the Super Nintendo Entertainment System, it was released on June 23, 1996, in Japan, on September 29, 1996, in North America, and on March 1, 1997, in Europe and Australia. It was the last major home console to use cartridges as its primary storage format until the Nintendo Switch in 2017. It competed primarily with the Sony PlayStation and the Sega Saturn.


title: Nintendo 64

text: Development began in 1993 in partnership with Silicon Graphics, using the codename Project Reality, then a test model and arcade platform called Ultra 64. The final design was named after its 64-bit CPU, which aided in the console's 3D capabilities. Its design was mostly complete by mid-1995 and launch was delayed until 1996 for the completion of the launch games "Super Mario 64", "Pilotwings 64", and "Saikyō Habu Shōgi" (exclusive to Japan). The charcoal-gray console was followed by a series of color variants. Some games require the Expansion Pak accessory to increase system RAM from 4MB to 8MB, for improved graphics and functionality. The console mainly supports saved game storage either onboard cartridges or on the Controller Pak accessory. The 64DD peripheral drive hosts both exclusive games and expansion content for cartridges, with many further accessories plus the defunct Internet service Randnet, but it was a commercial failure and was only released in Japan.


title: Nintendo 64

text: "Time" named it Machine of the Year in 1996, and in 2011, "IGN" named it the ninth-greatest video game console of all time.


title: Nintendo 64

text: The Nintendo 64 was discontinued in 2002 following the 2001 launch of its successor, the GameCube. The Nintendo 64 was critically acclaimed and remains one of the most recognized video game consoles.


title: Nintendo 64

text: Following the video game crash of 1983, Nintendo led the industry with its first home game console, the Famicom, originally released in Japan in 1983 and later released internationally as the Nintendo Entertainment System (NES) beginning in 1985. Though the NES and its successor, the Super Nintendo Entertainment System (SNES), were commercially successful, sales for the SNES decreased as a result of the Japanese recession. Competition from emerging rival Sega's 32-bit Saturn console over Nintendo's 16-bit SNES emphasized Nintendo's need to develop improved SNES hardware or risk losing market dominance to its competitors. The Atari 5200, 7800, Lynx, and Jaguar also competed with Nintendo during this time.


title: Nintendo 64

text: Nintendo sought to enhance the SNES with a proposed CD-ROM peripheral, to be developed by outsourcing media companies. Contracts with CD-ROM technology pioneers Philips and Sony failed after some hardware prototypes, and no games from them or other interested third parties. Philips used the software portion of its license by releasing original "Mario" and "Zelda" games on its competing CD-i console, and Sony salvaged its internal progress to develop the PlayStation. Nintendo's third-party developers protested its strict licensing policies.


title: Nintendo 64

text: Silicon Graphics, Inc. (SGI), a long-time leader in graphics computing, was exploring expansion by adapting its supercomputing technology into the higher volume consumer market, starting with the video game market. SGI reduced its MIPS R4000 family of enterprise CPUs, to consume only 0.5 watts of power instead of 1.5 to 2 watts, with an estimated target price of instead of –200. The company created a design proposal for a video game chipset, seeking an established partner in that market. Jim Clark, founder of SGI, offered the proposal to Tom Kalinske, who was the CEO of Sega of America. The next candidate would be Nintendo.


title: Nintendo 64

text: Kalinske said that he and Joe Miller of Sega of America were "quite impressed" with SGI's prototype, and invited their hardware team to travel from Japan to meet with SGI. The engineers from Sega Enterprises said that their evaluation of the early prototype had revealed several hardware problems. Those were subsequently resolved, but Sega had already decided against SGI's design. Nintendo disputed this account, arguing that SGI chose Nintendo because Nintendo was the more appealing partner. Sega demanded exclusive rights to the chip, but Nintendo offered a non-exclusive license. Michael Slater, publisher of "Microprocessor Report" said, "The mere fact of a business relationship there is significant because of Nintendo's phenomenal ability to drive volume. If it works at all, it could bring MIPS to levels of volume [SGI] never dreamed of."


title: Nintendo 64

text: Jim Clark met with the CEO of Nintendo at the time, Hiroshi Yamauchi in early 1993, initiating Project Reality. On August 23, 1993, the companies announced a global joint development and licensing agreement surrounding Project Reality, projecting that the yet unnamed product would be "developed specifically for Nintendo, would be unveiled in arcades in 1994, and would be available for home use by late 1995 ... below $250". This announcement coincided with Nintendo's August 1993 Shoshinkai trade show.


title: Nintendo 64

text: SGI had named the core components Reality Immersion Technology, which would be first used in Project Reality: the MIPS R4300i CPU, the MIPS Reality Coprocessor, and the embedded software. Some chip technology and manufacturing was provided by NEC, Toshiba, and Sharp. SGI had recently acquired MIPS Computer Systems (renamed to MIPS Technologies), and the two worked together to be ultimately responsible for the design of the Reality Immersion Technology chips under engineering director Jim Foran and chief hardware architect Tim Van Hook.


title: Nintendo 64

text: The initial Project Reality game development platform was developed and sold by SGI in the form of its Onyx supercomputer costing – and loaded with the namesake RealityEngine2 graphics boards and four 150 MHz R4400 CPUs. Its software includes early Project Reality application and emulation APIs based on Performer and OpenGL. This graphics supercomputing platform had served as the source design which SGI had reduced down to become the Reality Immersion Technology for Project Reality.


title: Nintendo 64

text: The Project Reality team prototyped a game controller for the development system by modifying a Super NES controller to have a primitive analog joystick and Z trigger. Under maximal secrecy even from the rest of the company, a LucasArts developer said his team would "furtively hide the prototype controller in a cardboard box while we used it. In answer to the inevitable questions about what we were doing, we replied jokingly that it was a new type of controllera bowl of liquid that absorbed your thoughts through your fingertips. Of course, you had to think in Japanese..."


title: Nintendo 64

text: On June 23, 1994, Nintendo announced the new official name of the still unfinished console as "Ultra 64". The first group of elite developers selected by Nintendo was nicknamed the "Dream Team": Silicon Graphics, Inc.; Alias Research, Inc.; Software Creations; Rambus, Inc.; MultiGen, Inc.; Rare, Ltd. and Rare Coin-It Toys & Games, Inc.; WMS Industries, Inc.; Acclaim Entertainment, Inc.; Williams Entertainment, Inc.; Paradigm Simulation, Inc.; Spectrum Holobyte; DMA Design Ltd.; Angel Studios; Ocean; Time Warner Interactive; and Mindscape.


title: Nintendo 64

text: By purchasing and developing upon Project Reality's graphics supercomputing platform, Nintendo and its Dream Team could begin prototyping their games according to SGI's estimated console performance profile, prior to the finalization of the console hardware specifications. When the Ultra 64 hardware was finalized, that supercomputer-based prototyping platform was later supplanted by a much cheaper and fully accurate console simulation board to be hosted within a low-end SGI Indy workstation in July 1995. SGI's early performance estimates based upon its supercomputing platform were ultimately reported to have been fairly accurate to the final Ultra 64 product, allowing LucasArts developers to port their "Star Wars" game prototype to console reference hardware in only three days.


title: Nintendo 64

text: The console's design was publicly revealed for the first time in late Q2 1994. Images of the console displayed the Nintendo Ultra 64 logo and a ROM cartridge, but no controller. This prototype console's form factor would be retained by the product when it eventually launched. Having initially indicated the possibility of utilising the increasingly popular CD-ROM if the medium's endemic performance problems were solved, the company now announced a much faster but space-limited cartridge-based system, which prompted open analysis by the gaming press. The system was frequently marketed as the world's first 64-bit gaming system, often stating the console was more powerful than the first moon landing computers. Atari had already claimed to have made the first 64-bit game console with their Atari Jaguar, but the Jaguar only uses a general 64-bit architecture in conjunction with two 32-bit RISC processors and a 16/32-bit Motorola 68000.


title: Nintendo 64

text: Later in Q2 1994, Nintendo signed a licensing agreement with Midway's parent company which enabled Midway to develop and market arcade games with the Ultra 64 brand, and formed a joint venture company called "Williams/Nintendo" to market Nintendo-exclusive home conversions of these games. The result is two Ultra 64 branded arcade games, "Killer Instinct" and "Cruis'n USA". Not derived from Project Reality's console-based branch of Ultra 64, the arcade branch uses a different MIPS CPU, has no Reality Coprocessor, and uses onboard ROM chips and a hard drive instead of a cartridge. "Killer Instinct" features 3D character artwork pre-rendered into 2D form, and computer-generated movie backgrounds that are streamed off the hard drive and animated as the characters move horizontally.


title: Nintendo 64

text: Previously, the plan had been to release the console with the name "Ultra Famicom" in Japan and "Nintendo Ultra 64" in other markets. Rumors circulated attributing the name change to the possibility of legal action by Konami's ownership of the Ultra Games trademark. Nintendo said that trademark issues were not a factor, and the sole reason for any name change was to establish a single worldwide brand and logo for the console. The new global name "Nintendo 64" was proposed by "Earthbound" series developer Shigesato Itoi. The prefix for the model numbering scheme for hardware and software across the Nintendo 64 platform is "NUS-", a reference to the console's original name of "Nintendo Ultra Sixty-four".


title: Nintendo 64

text: The newly renamed Nintendo 64 console was fully unveiled to the public in playable form on November 24, 1995, at Nintendo's 7th Annual Shoshinkai trade show. Eager for a preview, "hordes of Japanese schoolkids huddled in the cold outside ... the electricity of anticipation clearly rippling through their ranks". "Game Zero" magazine disseminated photos of the event two days later. Official coverage by Nintendo followed later via the "Nintendo Power" website and print magazine.


title: Nintendo 64

text: The console was originally slated for release by Christmas of 1995. In May 1995, Nintendo delayed the release to April 1996. Consumers anticipating a Nintendo release the following year at a lower price than the competition reportedly reduced the sales of competing Sega and Sony consoles during the important Christmas shopping season. "Electronic Gaming Monthly" editor Ed Semrad even suggested that Nintendo may have announced the April 1996 release date with this end in mind, knowing in advance that the system would not be ready by that date.


title: Nintendo 64

text: In its explanation of the delay, Nintendo claimed it needed more time for Nintendo 64 software to mature, and for third-party developers to produce games. Adrian Sfarti, a former engineer for SGI, attributed the delay to hardware problems; he claimed that the chips underperformed in testing and were being redesigned. In 1996, the Nintendo 64's software development kit was completely redesigned as the Windows-based Partner-N64 system, by Kyoto Microcomputer, Co. Ltd. of Japan.


title: Nintendo 64

text: The Nintendo 64's release date was later delayed again, to June 23, 1996. Nintendo said the reason for this latest delay, and in particular, the cancellation of plans to release the console in all markets worldwide simultaneously, was that the company's marketing studies now indicated that they would not be able to manufacture enough units to meet demand by April 1996, potentially angering retailers in the same way Sega had done with its surprise early launch of the Saturn in North America and Europe.


title: Nintendo 64

text: To counteract the possibility that gamers would grow impatient with the wait for the Nintendo 64 and purchase one of the several competing consoles already on the market, Nintendo ran ads for the system well in advance of its announced release dates, with slogans like "Wait for it..." and "Is it worth the wait? Only if you want the best!"


title: Nintendo 64

text: "Popular Electronics" called the launch a "much hyped, long-anticipated moment". Several months before the launch, "GamePro" reported that many gamers, including a large percentage of their own editorial staff, were already saying they favored the Nintendo 64 over the Saturn and PlayStation.


title: Nintendo 64

text: The console was first released in Japan on June 23, 1996. Though the initial shipment of 300,000 units sold out on the first day, Nintendo successfully avoided a repeat of the Super Famicom launch day pandemonium, in part by using a wider retail network which included convenience stores. The remaining 200,000 units of the first production run shipped on June 26 and 30, with almost all of them reserved ahead of time. In the months between the Japanese and North American launches, the Nintendo 64 saw brisk sales on the American gray market, with import stores charging as much as $699 plus shipping for the system. The Nintendo 64 was first sold in North America on September 26, 1996, though having been advertised for the 29th. It was launched with just two games in the United States, "Pilotwings 64" and "Super Mario 64"; "Cruis'n USA" was pulled from the line-up less than a month before launch because it did not meet Nintendo's quality standards. In 1994, prior to the launch, Nintendo of America chairman Howard Lincoln emphasized the quality of first-party games, saying "... we're convinced that a few great games at launch are more important than great games mixed in with a lot of dogs". The PAL version of the console was released in Europe on March 1, 1997, except for France where it was released on September 1 of the same year. According to Nintendo of America representatives, Nintendo had been planning a simultaneous launch in Japan, North America, and Europe, but market studies indicated that worldwide demand for the system far exceeded the number of units they could have ready by launch, potentially leading to consumer and retailer frustration.


title: Nintendo 64

text: Originally intended to be priced at , the console was ultimately launched at to make it competitive with Sony and Sega offerings, as both the Saturn and PlayStation had been lowered to $199.99 earlier that summer. Nintendo priced the console as an impulse purchase, a strategy from the toy industry. The price of the console in the United States was further reduced in August 1998.


title: Nintendo 64

text: The Nintendo 64's North American launch was backed with a $54 million marketing campaign by Leo Burnett Worldwide (meaning over $100 in marketing per North American unit that had been manufactured up to this point). While the competing Saturn and PlayStation both set teenagers and adults as their target audience, the Nintendo 64's target audience was pre-teens.


title: Nintendo 64

text: To boost sales during the slow post-Christmas season, Nintendo and General Mills worked together on a promotional campaign that appeared in early 1999. The advertisement by Saatchi and Saatchi, New York began on January 25 and encouraged children to buy Fruit by the Foot snacks for tips to help them with their Nintendo 64 games. Ninety different tips were available, with three variations of thirty tips each.


title: Nintendo 64

text: Nintendo advertised its Funtastic Series of peripherals with a $10 million print and television campaign from February 28 to April 30, 2000. Leo Burnett Worldwide was in charge again.


title: Nintendo 64

text: The console's main microprocessor is a 64-bit NEC VR4300 CPU with a clock rate of 93.75 MHz and a performance of 125 MIPS. "Popular Electronics" said it had power similar to the Pentium processors found in desktop computers. Except for its narrower 32-bit system bus, the VR4300 retained the computational abilities of the more powerful 64-bit MIPS R4300i, though software rarely took advantage of 64-bit data precision operations. Nintendo 64 games generally used faster and more compact 32-bit data-operations, as these were sufficient to generate 3D-scene data for the console's RSP (Reality Signal Processor) unit. In addition, 32-bit code executes faster and requires less storage space (which is at a premium on the Nintendo 64's cartridges).


title: Nintendo 64

text: In terms of its random-access memory (RAM), the Nintendo 64 was one of the first consoles to implement a unified memory subsystem, instead of having separate banks of memory for CPU, audio, and video operations. The memory itself consists of 4 megabytes of Rambus RDRAM, expandable to 8 MB with the Expansion Pak. Rambus was quite new at the time and offered Nintendo a way to provide a large amount of bandwidth for a relatively low cost.


title: Nintendo 64

text: Audio may be processed by the Reality Coprocessor or the CPU and is output to a DAC with up to sample rate.


title: Nintendo 64

text: The system allows for video output in two formats: composite video and S-Video. The composite and S-Video cables are the same as those used with the preceding Super NES and succeeding GameCube platforms.


title: Nintendo 64

text: The Nintendo 64 supports 16.8 million colors. The system can display resolutions from 320×240 up to 640×480 pixels. Most games that make use of the system's higher resolution mode require use of the Expansion Pak RAM upgrade; though several do not, such as Acclaim's "NFL Quarterback Club" series and EA Sports's second generation "Madden", "FIFA", "Supercross", and "NHL" games. The majority of games use the system's low resolution 320×240 mode. Many games support a video display ratio of up to using either anamorphic widescreen or letterboxing.


title: Nintendo 64

text: The controller of the Nintendo 64 is designed in an "M" shape and features 10 buttons, one analog control stick and a directional pad.


title: Nintendo 64

text: The Nintendo 64 is one of the first gaming consoles to have four controller ports. According to Shigeru Miyamoto, Nintendo opted to have four controller ports because the Nintendo 64 is the company's first console which can handle a four player split screen without significant slowdown.


title: Nintendo 64

text: Nintendo 64 games are ROM cartridge based. Cartridge size varies from 4 to 64 MB. Many cartridges include the ability to save games internally.


title: Nintendo 64

text: Nintendo cited several advantages for making the Nintendo 64 cartridge-based. Primarily cited was the ROM cartridges' very fast load times in comparison to disc-based games. While loading screens appear in many PlayStation games, they are rare in Nintendo 64 games. Although vulnerable to long-term environmental damage, the cartridges are far more resistant to physical damage than compact discs. Nintendo also cited the fact that cartridges are more difficult to pirate than CDs, thus resisting copyright infringement, albeit at the expense of lowered profit margin for Nintendo. While unauthorized N64 interface devices for the PC were later developed, these devices are rare, when compared to a regular CD drive used on the PlayStation which suffered widespread copyright infringement.


title: Nintendo 64

text: On the downside, cartridges took longer to manufacture than CDs, with each production run (from order to delivery) taking two weeks or more. This meant that publishers of Nintendo 64 games had to attempt to predict demand for a game ahead of its release. They risked being left with a surplus of expensive cartridges for a failed game or a weeks-long shortage of product if they underestimated a game's popularity. The cost of producing a Nintendo 64 cartridge was also far higher than for a CD. Publishers passed these expenses onto the consumer. Nintendo 64 games cost an average of $10 more when compared to games produced for rival consoles. The higher cost also created the potential for much greater losses to the game's publisher in the case of a flop, making the less risky CD medium tempting for third-party companies. Some third-party companies also complained that they were at an unfair disadvantage against Nintendo first party developers when publishing games for the Nintendo 64, since Nintendo owned the manufacturing plant where cartridges for their consoles are made and therefore could sell their first party games at a lower price.


title: Nintendo 64

text: As fifth generation games became more complex in content, sound and graphics, games began to exceed the limits of cartridge storage capacity. Nintendo 64 cartridges had a maximum of 64 MB of data, whereas CDs held 650 MB. The "Los Angeles Times" initially defended the quality control incentives associated with working with limited storage on cartridges, citing Nintendo's position that cartridge game developers tend to "place a premium on substance over flash", and noted that the N64 launch games are free of "poorly acted live-action sequences or half-baked musical overtures" which it says tend to be found on CD-ROM games. However, the cartridge's limitations became apparent with software ported from other consoles, so Nintendo 64 versions of cross-platform games were truncated or redesigned with the storage limits of a cartridge in mind. For instance this meant fewer textures, and/or shorter music tracks, while full motion video was not usually feasible for use in cutscenes unless heavily compressed and of very brief length.


title: Nintendo 64

text: The era's competing systems from Sony and Sega (the PlayStation and Saturn, respectively) used CD-ROM discs to store their games. As a result, game developers who had traditionally supported Nintendo game consoles were now developing games for the competition. Some third-party developers, such as Square and Enix, whose "Final Fantasy VII" and "Dragon Warrior VII" were initially planned for the Nintendo 64, switched to the PlayStation, citing the insufficient storage capacity of the N64 cartridges. Some who remained released fewer games to the Nintendo 64; Konami released fifty PlayStation games, but only twenty nine for the Nintendo 64. New Nintendo 64 game releases were infrequent while new games were coming out rapidly for the PlayStation.


title: Nintendo 64

text: Through the difficulties with third parties, the Nintendo 64 supported popular games such as "GoldenEye 007", giving it a long market life. Additionally, Nintendo's strong first-party franchises such as "Mario" had strong name brand appeal. Second-parties of Nintendo, such as Rare, helped.


title: Nintendo 64

text: Nintendo's controversial selection of the cartridge medium for the Nintendo 64 has been cited as a key factor in Nintendo losing its dominant position in the gaming market. The ROM cartridges are constrained by small capacity and high production expenses, compared to the compact disc format used by its chief competitors. Some of the cartridge's advantages are difficult for developers to manifest prominently, requiring innovative solutions which only came late in the console's life cycle. Another of its technical drawbacks is a limited-size texture cache, which force textures of limited dimensions and reduced color depth, appearing stretched when covering in-game surfaces. Some third-party publishers that supported Nintendo's previous consoles reduced their output or stopped publishing for the console; the majority of the Nintendo 64's most successful games came from first-party or second-party studios.


title: Nintendo 64

text: The Nintendo 64 comes in several colors. The standard Nintendo 64 is dark gray, nearly black, and the controller is light gray (later releases in the U.S., Canada, and Australia included a bonus second controller in Atomic Purple). Various colorations and special editions were released.


title: Nintendo 64

text: Most Nintendo 64 game cartridges are gray in color, but some games have a colored cartridge. Fourteen games have black cartridges, and other colors (such as yellow, blue, red, gold, and green) were each used for six or fewer games. Several games, such as "", were released both in standard gray and in colored, limited edition versions.


title: Nintendo 64

text: The programming characteristics of the Nintendo 64 present unique challenges, with distinct potential advantages. "The Economist" described effective programming for the Nintendo 64 as being "horrendously complex". As with many other game consoles and other types of embedded systems, the Nintendo 64's architectural optimizations are uniquely acute, due to a combination of oversight on the part of the hardware designers, limitations on 3D technology of the time, and manufacturing capabilities.


title: Nintendo 64

text: As the Nintendo 64 reached the end of its lifecycle, hardware development chief Genyo Takeda repeatedly referred to the programming challenges using the word . Looking back, Takeda said "When we made Nintendo 64, we thought it was logical that if you want to make advanced games, it becomes technically more difficult. We were wrong. We now understand it's the cruising speed that matters, not the momentary flash of peak power".


title: Nintendo 64

text: In contrast to the NES and the Super NESwith unique names and hardware designs in JapanNintendo developed the same brand and hardware design for the Nintendo 64 in every region worldwide. The company initially stated that regional lock-out chips would be the chief distinction to localize games. Following the North American launch, it stated that regional lock-out is enforced by unique notches in the back of cartridges instead of chips.


title: Nintendo 64

text: A total of 393 games were released for the Nintendo 64, though there were a few games that were exclusively sold in Japan. For comparison, rivals PlayStation and the Sega Saturn received around 1,100 games and 600 games, respectively, while previous Nintendo consoles such as the NES and Super NES had 768 and 725 games released in the United States. The considerably smaller Nintendo 64 game library has been attributed to the controversial decision not to adopt the CD-ROM, and programming difficulties for its complex architecture (see above). This trend is also seen as a result of Hiroshi Yamauchi's strategy, announced during his speech at the Nintendo 64's November 1995 unveiling, that Nintendo would be restricting the number of games produced for the Nintendo 64 so that developers would focus on developing games to a higher standard instead of trying to outdo their competitors with sheer quantity. The "Los Angeles Times" also observed that this was part of Nintendo's "penchant for perfection", as "while other platforms offer quite a bit of junk, Nintendo routinely orders game developers back to the boards to fix less-than-perfect titles".


title: Nintendo 64

text: Although having less third-party support than rival consoles, Nintendo's strong first-party franchises such as "Mario" enjoyed wide brand appeal. Second-parties of Nintendo, such as Rare, released groundbreaking titles. Consequently, the Nintendo 64 game library included a high number of critically acclaimed and widely sold games. According to TRSTS reports, three of the top five best-selling games in the U.S. for December 1996 were Nintendo 64 games (both of the remaining two were Super NES games). "Super Mario 64" is the best-selling console game of the generation, with 11 million units sold beating "Gran Turismo" for the PlayStation (at 10.85 million) and "Final Fantasy VII" (at 9.72 million) in sales. The game also received much praise from critics and helped to pioneer three-dimensional control schemes. "GoldenEye 007" was important in the evolution of the first-person shooter, and has been named one of the greatest in the genre. "" set the standard for future 3D action-adventure games and is considered by many to be one of the greatest games ever made.


title: Nintendo 64

text: The most graphically demanding Nintendo 64 games that arrived on larger 32 or 64 MB cartridges are the most advanced and detailed of the 32-bit/64-bit generation. In order to maximize use of the Nintendo 64 hardware, developers had to create their own custom microcode. Nintendo 64 games running on custom microcode benefited from much higher polygon counts in tandem with more advanced lighting, animation, physics and AI routines than its 32-bit competition. "Conker's Bad Fur Day" is arguably the pinnacle of its generation combining multicolored real-time lighting that illuminates each area to real-time shadowing and detailed texturing replete with a full in game facial animation system. The Nintendo 64's graphics chip is capable of executing many more advanced and complex rendering techniques than its competitors. It is the first home console to feature trilinear filtering, which allowed textures to look very smooth. This contrasted with the Saturn and PlayStation, which used nearest-neighbor interpolation and produced more pixelated textures. Overall however the results of the Nintendo cartridge system were mixed and this was tied primarily to its storage medium.


title: Nintendo 64

text: The smaller storage size of ROM cartridges limited the number of available textures. As a result, many games which utilized much smaller 8 or 12 MB cartridges are forced to stretch textures over larger surfaces. Compounded by a limit of 4,096 bytes of on-chip texture memory, the end-result is often a distorted, out-of-proportion appearance. Many games with larger 32 or 64 MB cartridges avoid this issue entirely, including "Resident Evil 2", "Sin and Punishment: Successor of the Earth", and "Conker's Bad Fur Day", allowing for more detailed graphics with multiple, multi-layered textures across all surfaces.