Hydralazine therapy in chronic congestive heart failure: Sustained central and regional hemodynamic responses

Central and regional hemodynamic parameters were evaluated at baseline and following three months of placebo or hydralazlne therapy (100 mg orally every eight hours) in 20 patients with idiopathic dilated cardiomyopathy. Both control (placebo) and hydralazine groups were comparable with respect to functional classification (New York Heart Association classes III and IV) and baseline hemodynamic variables. In the hydralazine group, cardiac index increased 25 percent (2.4 ± 0.4 to 3.0 ± 0.5 liters/minute/m 2), renal blood flow increased 26 percent (648 ± 199 to 815 ± 229 ml/minute), and limb blood flow was augmented by 35 percent (6.8 ± 3.0 to 9.2 ± 4.6 ml/dl/minute) with long-term therapy. These changes were significant (all p < 0.05) when compared with both baseline values and values in the control group. Both central and regional hemodynamic parameters remained unaltered in the control group. Long-term hydralazine therapy (three months) elicited a favorable circulatory response in this group of patients with chronic congestive heart failure. Central or regional hemodynamic tolerance to oral hydralazine failed to develop in the majority of patients.