Is syncope the same thing as sudden death except that you wake up?

Syncope in Patients with Organic Heart Disease

Patients with syncope and organic heart disease remain a small but important subset of those patients who experience transient loss of consciousness. These patients require thoughtful and complete evaluation in an attempt to better understand the mechanism of syncope and its relationship to the underlying disease, and to diagnose and treat both properly. The goal is to reduce the risk of further syncope, to improve long-term outcomes with respect to arrhythmic and total mortality, and to improve patients' quality of life.

Sudden death risk in syncope: the role of the implantable cardioverter defibrillator

Syncope is generally benign but when it is due to an underlying cardiovascular condition, the prognosis can be guarded. Patients with syncope may be at risk of dying suddenly from a ventricular arrhythmia especially if the collapse is caused by a poorly-tolerated, self-terminating, ventricular tachycardia (VT). If a similar VT recurs, and persists, it could initiate cardiac arrest, leading to sudden cardiac death. However, distinguishing which patient with syncope may benefit most from implantable cardioverter defibrillator (ICD) therapy, which can stop life-threatening and poorly tolerated VT, thereby preventing sudden cardiac death, remains an ongoing challenge. Careful assessment of the patient's underlying cardiovascular conditions, scrupulous attention to historical detail to assess potential causes for syncope, and risk stratification based upon clinical characteristics and short and long-term risks can help. This review focuses on the sudden death risk in patients with syncope and explores the role of the ICD to treat ventricular arrhythmias, prevent symptoms, and prevent death.

Sudden Cardiac Death in the Young: A Strategy for Prevention by Targeted Evaluation

The annual incidence of sudden cardiac death (SCD) in the general population is estimated as 1 in a 1,000. Since survival rates from out-of-hospital cardiac arrests are poor, primary prevention is key to reducing the burden of SCD in the community. Prominent causes of SCD include ischaemic heart disease, anomalous coronary arteries, and the primary myocardial diseases: hypertrophic cardiomyopathy, dilated cardiomyopathy, and ar rhythmogenic right ventricular cardiomyopathy (ARVC). In 4% of sudden deaths in the 16-64 age group, post-mortem examination fails to identify a cause, yielding a default diagnosis of sudden arrhythmic death syndrome (SADS). The inherited arrhythmia syndromes (long QT, short QT, and Brugada syndromes, and familial catecholaminergic polymorphic ventricular tachycardia) may be implicated in SADS, owing to their propensity for producing ventricular tachyarrhythmia in the structurally normal heart. Monogenic disorders therefore predominate as causes of SCD in the young. The advent of effective therapies for these diseases, particularly implantable cardioverter defibrillators, has prompted calls for universal screening to enable timely diagnosis of occult cardiac disease. Since prospective cardiac assessment of the general population is not feasible, the solution may be to target high-risk subgroups, namely, patients with cardiac symptoms, relatives of SCD victims, and competitive athletes. The recommended preliminary work-up includes a 12-lead ECG, signal-averaged ECG, transthoracic echocardiogram, exercise test, and ambulatory ECG monitoring. Cardiovascular magnetic resonance is a useful adjunct in patients with suspected ARVC or anomalous coronary arteries. Provocative challenge with a sodium challenge blocker may be of value in unmasking the Brugada syndrome. Identification of disease-causing mutations in affected individuals facilitates cascade screening of families.