Can pharmacological therapy influence the mortality of chronic congestive heart failure?

The prognosis of patients with advanced left heart failure is fairly dismal. It was not until recently that studies were conducted demonstrating the poor prognosis can be modulated by drug therapy. Of the many vasodilators tested, positive data have emerged only from trials of high-dose nitrates with hydralazine and, most importantly, angiotensin-converting enzyme inhibitors believed to constitute the biggest step forward in the treatment of chronic heart failure. The agents included in this group improve the symptomatology, increase exercise tolerance and improve the prognosis. At present, they are indicated in cases of severe heart failure, and the potential of their use in the more severe forms as well as in patients after myocardial infarction is being intensively investigated. Still, diuretic remain the mainstay of drug therapy. The role of digitalis in the treatment of heart failure is being currently reviewed; its administration is unnecessary in most patients, especially those with maintained sinus rhythm. A number of other positive inotropic drugs, both catecholamine-based agents and phosphodiesterase inhibitors (amrinone, milrinone, xamoterol, enoximone) have been tested. Their effect in the chronic form, unlike acute failure, is controversial, and there is no evidence documenting improved prognosis; some studies even show an adverse trend. As almost 50% of patients with heart failure die suddenly, it would have been only logical to administer antiarrhythmics to them. However, no data demonstrating an improved prognosis are available either. Results of studies conducted to date have proved to be rather disappointing, and a study with the most promising antiarrhythmic drug--amiodarone--is still under way.