Current Concepts of Premature Ventricular Contractions

Premature ventricular contractions (PVCs) are early depolarizations of the myocardium originating in the ventricle. PVCs are common with an estimated prevalence of 40% to 75% in the general population on 24- to 48-hour Holter monitoring. Traditionally, they have been thought to be relatively benign in the absence of structural heart disease but they represent increased risk of sudden death in structural heart disease. Especially in ischemic heart disease, the frequency and complexity of PVCs is associated with mortality. Implantable cardioverter defibrillator therapy is indicated in patients with nonsustained ventricular tachycardia (NSVT) due to prior myocardial infarction, left ventricular ejection fraction less than or equal to 40%, and inducible ventricular fibrillation or sustained ventricular tachycardia at electrophysiological study. In congestive heart failure, PVCs did not provide significant incremental prognostic information beyond readily available clinical variables. Consequently, NSVT should not guide therapeutic interventions. Recently, the concept of PVC-induced cardiomyopathy was proposed when pharmacological suppression of PVCs in patients with presumed idiopathic dilated cardiomyopathy subsequently showed improved left ventricular systolic dysfunction. For the treatment PVCs, it is important to consider underlying heart disease, the frequency of the PVCs and the frequency and severity of symptoms.