Hemodynamic and clinical effects of captopril in congestive heart failure

The acute and chronic effects of Captopril were evaluated in 8 patients (5 males and 3 females, age 49 +/- 17 years) with chronic severe congestive heart failure. Acute hemodynamic effects were studied according to a randomized, double blind, placebo controlled protocol, by using two doses of Captopril (25 and 50 mg). The usual diuretic and digitalis treatment was kept unchanged throughout the trial. The acute administration of placebo associate with the usual doses of diuretic and digitalis was followed after 2 hours by a significant reduction of mean pulmonary wedge pressure (-23%, p less than 0.05). One hour following a single administration of Captopril, the following significant (p less than 0.05) changes were observed, respectively for the doses of 25 and 50 mg: heart rate -9% and -6%, cardiac index +13% and +10%, mean pulmonary wedge pressure -27% and -35%, mean pulmonary arterial pressure -29% and -26%, systemic vascular resistances -20% and -17%. A longer duration of effects on heart rate and cardiac index was noted after the 50 mg dose. All patients received long-term treatment with Captopril 75 or 150 mg daily. The NYHA functional class improved in all cases and there was a significant decrease of the cardio-thoracic ratio (from 0.61 +/- 0.05 to 0.55 +/- 0.09, p less than 0.01). A repeated hemodynamic study after a mean period of 6.5 months (range 2.5-22 months) revealed in 7 cases a sustained effect of the drug.(ABSTRACT TRUNCATED AT 250 WORDS)