Heart Failure and Ventricular Arrhythmias: Prognostic Indices of Mortality and Therapeutic Options

Patients with chronic heart failure show a high incidence of complex ventricular ectopic activity and high mortality, with an average sudden death rate of 46%. Given the close relationship between ventricular ectopic activity and left ventricular function, it is difficult to determine whether the ventricular ectopic activity has independent prognostic significance in patients with chronic heart failure. Notwithstanding, several large scale clinical studies have shown that left ventricular dysfunction is the first independent prognostic index in patients with ischaemic or dilative idiopathic cardiomyopathy. Therefore, potentially reversible causes of arrhythmia should be diagnosed and if necessary corrected. Electrophysiological testing and noninvasive techniques are used for evaluating arrhythmia mechanisms and establishing drug efficacy. Empirical therapy of potentially malignant ventricular arrhythmias in patients with ischaemic or dilative idiopathic cardiomyopathy has proved unsatisfactory because of both the inadequate control obtained and the increasing evidence that antiarrhythmic drugs are arrhythmogenic. In selected groups of patients, however, empirical therapy with amiodarone may reduce the frequency and complexity of the ventricular ectopic activity and incidence of sudden death. The use of drugs with an indirect antiarrhythmic action, such as β-blockers and angiotensin converting enzyme (ACE) inhibitors, has been shown to decrease the mortality and incidence of sudden cardiac death in some groups of patients with chronic heart failure. A further step forward in the treatment of patients at high risk of sudden death is represented by nonpharmacological therapy, i.e. excision of aneurysm, surgical or electrical ablation of arrhythmogenic foci, and use of automatic implantable cardioverter defibrillators. © 1993, Adis International Limited. All rights reserved.