Acute Hemodynamic Effects of the Vasodilating and Beta-blocking Agent Carvedilol in Comparison to Propranolol

In a randomized double-blind study, oral doses of 50 mg carvedilol were compared to 40 mg propranolol in 16 male patients with coronary heart disease (12 without significant stenosis after percutaneous transluminal coronary angioplasty) at rest, during and after exercise, and before and 80 min after drug application. Systemic and pulmonary pressures, heart rate, cardiac index, and lower limb blood flow were measured, and systemic and pulmonary resistances calculated. Carvedilol does not lead, as the classical beta-blocker propranolol does, to an increase in systemic or pulmonary resistance, nor to a decrease in cardiac output, or to an increase of the pulmonary capillary wedge pressure during exercise. In contrast to propranolol, the postexercise lower limb blood flow has increased significantly. The differences in action between the two beta-blockers can be explained by the vasodilating properties of carvedilol. Due to these acute effects, carvedilol may be of advantage compared to propranolol in the treatment of peripheral occlusive artery disease, hypertension, and coronary vasospasm.