Oral hydralazine produced a greater increase in cardiac index and a lesser fall in pulmonary wedge pressure (5.5 vs 9.9 mm Hg, P<0.001) compared to nitroprusside in left ventricular failure.
Does a single oral dose of hydralazine improve hemodynamics compared to nitroprusside infusion in patients with left ventricular failure due to cardiomyopathy?
A single oral dose of hydralazine produces sustained hemodynamic improvement in patients with left ventricular failure, suggesting its utility in chronic management.
Absolute Event Rate: 5.5% vs 9.9%
p-value: p=<0.001
Hydralazine was administered in a single oral dose of 50 to 100 mg in 16 patients with left ventricular failure due to cardiomyopathy. It produced sustained effects for at least 4 h characterized by a significant increase in cardiac output, a reduction in arterial and pulmonary arterial pressure, and a slight rise in heart rate. When compared to nitroprusside infusion in these same patients, hydralazine produced a similar reduction in systemic vascular resistance but a slightly greater increase in cardiac index (0.74 versus 0.95 litres/min-m2), with a lesser fall in mean arterial pressure (7.8 versus 13.6 mm Hg, P less than 0.01), mean pulmonary arterial pressure (4.2 versus 11.3 mm Hg, P less than 0.001), and pulmonary wedge pressure (5.5 versus 9.9 mm Hg, P less than 0.001). Forearm venous tone decreased and venous compliance increased during nitroprusside infusion, but they were unchanged after hydralazine therapy. These data suggest that hydralazine may be a useful agent in the treatment of chronic left ventricular failure.
Franciosa et al. (1977) studied left ventricular failure due to cardiomyopathy (n=16). Oral hydralazine vs. nitroprusside infusion was evaluated on fall in pulmonary wedge pressure (mm Hg) (p=<0.001). Oral hydralazine produced a greater increase in cardiac index and a lesser fall in pulmonary wedge pressure (5.5 vs 9.9 mm Hg, P<0.001) compared to nitroprusside in left ventricular failure.