Vasodilators in heart failure secondary to coronary artery disease

Although vasodilators produce acute beneficial hemodynamic effects in patients with chronic congestive heart failure, their effects on the long-term management of such patients are unclear. In 56 patients followed up for an average of 13 months, there was a 37% mortality at 1 year. Because of the potential adverse effects of vasodilators in patients with coronary artery disease, we evaluated the effects of prazosin, hydralazine, and isosorbide dinitrate on hemodynamics, coronary sinus flow, and myocardial oxygen consumption (MVO2). Isosorbide dinitrate reduced ventricular filling pressure with no change in heart rate or mean arterial pressure; coronary sinus flow and MVO2 fell significantly. With prazosin there was a reduction in ventricular filling pressures and rate-pressure product but no change in coronary sinus flow or MVO2. With hydralazine there were parallel changes in the rate-pressure product and MVO2. Results emphasize the differing effects of vasodilators on oxygen supply and demand, which may influence the long-term course of patients with coronary artery disease.