Sudden cardiac death: epidemiology and prevention

Even if sudden cardiac death is considered to be the most frequent cause of death in adults in industrialized countries, its incidence varies widely, depending on the definition and the source and quality of underlying data. It is estimated that about 70-80% of cases are due to coronary heart disease. The remaining 20% are attributable to a wide variety of inborn, genetically determined or acquired diseases, including a small group with hitherto undefined background. Prevention primarily encompasses the treatment of cardiovascular risk factors to avoid manifestations of coronary heart disease. Furthermore, preventive strategies are targeted to define groups of patients with an increased risk for sudden cardiac death or individuals at risk in specific populations, e.g. competitive athletes. A major target group are patients with impaired left ventricular function, preferentially due to myocardial infarction. These patients, and some less clearly defined patient groups with non-ischaemic cardiomyopathy and heart failure, may benefit from the insertion of an implantable cardioverter-defibrillator. With regard to pharmacological prevention, treatment of the underlying condition is the mainstay, since no antiarrhythmic substance-with the exemption of beta-blockers in some situations-has shown to be of efficacy.