This double-blind, placebo-controlled study evaluated the effects of the ACE inhibitor, quinapril, on the functional status of elderly frail heart failure patients with preserved systolic function. Seventy-four elderly patients, mean (SD) age 78 (7) years, with symptomatic heart failure (NYHA II-III) and normal or only mildly impaired left ventricular systolic function (ejection fraction > or =40%) were randomly assigned to receive either quinapril or matched placebo (titrated to 40 mg/day) for 6 months. There were no significant differences at baseline in terms of age, cardiac function, aetiology, concomitant treatment, and echocardiographic values between active and placebo groups. Mean 6-minute walk distance increased at six months in the quinapril group [241.2 (132.0) v 267.3 (124.0) metres, p=0.04] and in the placebo group [214.6 (114.5) v 267.6 (117.0) metres, p=0.003]. The mean increases between the two groups were not significantly different. There were no significant changes in quality of life scores. The number of adverse drug events was similar in the two groups. Patients in the quinapril group were less likely to have worsening heart failure or to be admitted to hospital but these changes were not statistically significant.
Conclusions: The present study confirmed the feasibility of single-centre drug trials in very elderly heart failure patients although recruitment and retention remain problematic. It did not show a beneficial effect of quinapril on exercise tolerance and quality of life in elderly heart failure patients with preserved systolic function.