Comparison of the effects of captopril and enoximone in patients with severe heart failure: a placebo controlled double-blind study

Abstract

The effects of enoximone, a new cyclic adenosine monophosphate phosphodiesterase inhibitor, were compared with those of captopril in a double-blind study in a group of 10 patients with severe heart failure. Four weeks treatment with enoximone improved sympton-limited exercise tolerance from a mean value of 11.33 to 13.36 minutes ( P < 0.05) and 4 weeks of captopril treatment from 11.01 to 13.92 minutes ( P < 0.05). Four of the patients had a greater exercise tolerance taking enoximone, the remaining 6 while taking captopril. Both drugs reduced perceived exertion during submaximal exercise. Minute ventilation measured at rest and during submaximal exercise was also reduced by both drugs. Resting and post exercise calf blood flow was increased to a similar extent with captopril ( P < 0.03) and enoximone ( P < 0.005). There was no difference in calf blood flow and calf vascular resistance between the drugs suggesting that the peripheral haemodynamic effects of enoximone are due to peripheral vasodilatation. Enoximone is a useful drug for the treatment of patients with severe heart failure.