Clinical experience in protecting the failing heart

Several large, carefully randomized studies of pharmaceutical agents in the treatment of patients with congestive heart failure (CHF) and left ventricular dysfunction have demonstrated conclusively that angiotensin-converting enzyme (ACE) inhibitors reduce mortality among patients with CHF, as well as the number of hospitalizations for heart failure, myocardial infarction (MI), and angina. ACE inhibitors also have been shown to prevent the development of heart failure in patients with asymptomatic left ventricular dysfunction. Phosphodiesterase inhibitors and the beta agonists have been shown to increase mortality with no beneficial effect on morbidity. The role of digitalis remains controversial. On the one hand, the limited data available suggest that digoxin prevents clinical deterioration in patients with heart failure, even in the presence of sinus rhythm. On the other hand, when administered after MI, digoxin has been associated with increased mortality. Such conclusions are unreliable, however, since it is impossible to adjust statistically for the fact that digoxin is used in sicker patients. This question will be addressed in a large randomized study currently being conducted by the Digitalis Investigation Group. Pharmacologic approaches to the reduction of sudden death currently being explored include amiodarone, oral magnesium supplements, and beta blockers. According to the Cardiac Arrhythmia Suppression Trial and other studies, the class I antiarrhythmic agents appear unpromising or even harmful. The calcium channel blockers also appear to be contraindicated as routine therapy for CHF.