Beta-blocking agents vs. antiarrhythmic interventions in heart failure complicated by arrhythmias

Approximately 40-50% of the patients with end-stage cardiac failure (either ischemic or nonischemic) die suddenly and unexpectedly, most probably from ventricular fibrillation. It is unclear whether the complex ventricular arrhythmias observed in large numbers of these patients were related to the mode of death. Theoretically, it seems quite reasonable to attempt to suppress the development of life-threatening ventricular arrhythmias (e.g., sustained ventricular tachycardia or ventricular fibrillation) in those patients. If antiarrhythmic drug therapy is ineffective, alternative antiarrhythmic interventions (antiarrhythmic surgery or implantation of an automatic implantable cardioverter defibrillator) should be considered. In patients with so-called potentially malignant ventricular arrhythmias (e.g., nonsustained ventricular tachycardia), antiarrhythmic drug therapy remains controversial as presently there is no definitive proof that this therapy prolongs life or reduces the incidence of sudden cardiac death. In patients with end-stage cardiac failure, beta-blockade can result in a decrease in resting tachycardia, improvement in clinical heart failure symptoms, and increase in work load capacity. It remains controversial whether treatment with these agents can also improve prognosis and prevent sudden cardiac death. Therefore, at this time, only patients in the earlier stages of this clinical syndrome and with clinical signs of markedly increased sympathetic tone can be treated with low doses of beta-blockers.