AHA/ACCF Scientific Statement on the Evaluation of Syncope: From the American Heart Association Councils on Clinical Cardiology, Cardiovascular Nursing, Cardiovascular Disease in the Young, and Stroke, and the Quality of Care and Outcomes Research Interdisciplinary Working Group; and the American College of Cardiology Foundation In Collaboration With the Heart Rhythm Society

Abstract

Introduction… 316 General Evaluation… 316 Syncope in the Patient With a Normal Evaluation… 318 Syncope in the Patient With Coronary Artery Disease… 319 Nonischemic Dilated Cardiomyopathy… 320 Syncope in Other Forms of Structural Heart Disease… 320 Syncope Resulting From Inherited Cardiac Ion Channel Abnormalities… 321 Evaluation of the Pediatric Patient With Syncope… 321 Special Considerations in the Elderly… 323 Neurological Evaluation… 323 Conclusions… 324 Syncope, a transient loss of consciousness, is a common clinical problem. The most common causes of syncope are cardiovascular in origin and are associated with a high rate of mortality in patients with underlying heart disease, transient myocardial ischemia, and other less common cardiac abnormalities.1 The primary purpose of the evaluation of the patient with syncope is to determine whether the patient is at increased risk for death. This involves identifying patients with underlying heart disease, myocardial ischemia, Wolff-Parkinson-White syndrome, and potentially life-threatening genetic diseases such as long-QT syndrome (LQTS), Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia. If these diagnoses can be excluded, the goal then becomes identification of the cause of syncope in an attempt to improve the quality of the patient’s life and to prevent injury to the patient or others. The purpose of this statement is to summarize the data that direct the evaluation of the patient with syncope (Figure 1). Figure 1. Flow chart for the diagnostic approach to the patient with syncope. In the general population, the most common cause of syncope is neurocardiogenic, followed by primary arrhythmias. Other names for neurocardiogenic syncope include neurally mediated, vasodepressor, and vasovagal syncope. The causes of syncope are highly age dependent.2 Pediatric and young patients are most likely to have neurocardiogenic syncope, conversion reactions (psychiatric causes), and primary arrhythmic causes such as the LQTS and Wolff-Parkinson-White syndrome. In middle age, neurocardiogenic syncope …