Angiotensin-converting enzyme inhibitor therapy improves respiratory muscle strength in patients with heart failure

Study objectives: Respiratory muscle strength has been shown to be reduced in patients with chronic heart failure. The purpose of this prospective stu dy was to determine whether long-term therapy with the angiotensin-converti ng enzyme (ACE) inhibitor perindopril improves respiratory muscle strength in patients with chronic heart failure. Patients and methods: Eighteen patients with stable chronic heart failure w ere administered perindopril, 4 mg/d, in addition to their standard therapy for a period of 6 months, Fourteen patients completed the study. Maximum i nspiratory pressure (PImax) and maximum expiratory pressure (PEmax) express ed in percentage of predicted values, left ventricular ejection fraction (L VEF) determined by means of two-dimensional echocardiography, and pulmonary volumes were obtained before and after therapy. Measurements and results: As compared to baseline, there was a significant increase in both PImax and PEmax after therapy (57 +/- 27% predicted vs 78 +/- 36% predicted and 62 +/- 20% predicted vs 73 +/- 15% predicted, respect ively; each p < 0.05), LVEF increased (34 +/- 5% vs 41 +/- 10%; p < 0.05); functional class improved by greater than or equal to 1 New York Heart Asso ciation (NYHA) class in five patients. There were no changes in pulmonary v olumes, No correlation was found between changes in PImax and PEmax and cha nges in either LVEF or NYHA functional class. Conclusions: In patients with chronic heart failure, long-term therapy with the ACE inhibitor perindopril improved respiratory muscle strength, as ind icated by significant increases in PImax and PEmax.