Hemodynamic advantage of combined administration of hydralazine orally and nitrates nonparenterally in the vasodilator therapy of chronic heart failure.

Patients with severe left ventricular failure generally have both reduced cardiac output and increased pulmonary and systemic venous pressures. A study was therefore made of the use of combined vasodilator therapy with nonparenterally administered nitrates, which act primarily on venous capacitance vessels and thus reduce preload, and orally administered hydralazine, which acts on arteriolar resistance vessels and thus reduces afterload. Twelve patients with chronic refractory heart failure were given these drugs individually and in combination during continuous hemodynamic monitoring. Heart rate and arterial pressure did not change significantly. Nitrates significantly reduced filling pressures of both ventricles without affecting cardiac index. Hydralazine did not alter filling pressures but dramatically increased cardiac index. The hemodynamic effects of each drug were additive during combined therapy, resulting in a 36 percent (28 to 18 mm Hg) mean decrease in left ventricular filling pressure and a 58 percent (2.1 to 3.3 liters/min per m(2)) mean increase in cardiac index. The seven patients who have continued to receive combined therapy for 3 to 10 months have shown sustained clinical improvement.