Sudden cardiac death: the role of risk stratification.

Sudden cardiac death syndrome remains a major health problem responsible for approximately 400,000 deaths annually in the US. Effective therapies exist but are costly and are associated with potential complications. Currently used strategies for selection of the best candidates for implantable cardioverter defibrillator (ICD) therapy are imperfect and leave a large number of high-risk patients unprotected. At the same time, many patients who received ICDs will never develop tachyarrhythmia and require ICD intervention. The article summarizes the current status and applicability of the noninvasive and invasive tests used for sudden cardiac death risk assessment with the emphasis on the increasingly recognized value of microvolt T wave alternans.