Ventricular arrhythmias in heart failure

In the management of patients with chronic heart failure, our attention is shifting from just improving left ventricular function and abolishing ventricular arrhythmias to improving personal longevity. Importantly, sudden cardiac death is a pattern of death in as many as a half of patients with chronic heart failure. Arrhythmias are common in this disorder, but may possibly be a marker of diseased heart rather than a predictor of sudden cardiac death. The mechanisms and triggers of rapid ventricular tachycardia or fibrillation responsible for sudden cardiac death have not been well established. At present, it is important to be reminded that pharmacologic augmentation of cardiac contractility or suppression of asymptomatic ventricular arrhythmias is not an effective approach to preventing sudden cardiac death, but may even be deleterious. Three groups of drugs that have shown efficacy in preventing sudden cardiac death in patients with chronic heart failure are amiodarone, beta-blockers, and angiotensin-converting enzyme (ACE) inhibitors. Although how these drugs improve prognosis of heart failure are not clear at present, myocardial protection by these agents appears to be most important.