ACE Inhibitors in Heart Failure-Switching from Enalapril to Perindopril

Although ACE inhibitors have demonstrated their beneficial effects in heart failure, whether different agents may induce different benefits remains unclear. We designed an open, sequential, prospective study switching heart failure patients receiving enalapril to perindopril which has been reported to be longer acting and better tolerated. The objective of the study was to find out if clinical and functional status could be further improved by changing from enalapril 30 mg daily to a perindopril 4 mg daily. Assessments of clinical status, echocardiography and nuclear ventriculography were performed at baseline under enalapril (30 mg mean dose (b.i.d.)), then 6 and 12 months after the switch to perindopril (4 mg/day mean dose). Thirty-one patients were included (90% men, aged 56.5 +/- 11.8 years, mean radionuclide left ventricular (LV) ejection fraction 22.4 +/- 8.5 %). After 6 months of treatment, NYHA functional class was significantly improved; the percentage of patients in class I increased to 57% after perindopril versus 20% at baseline (p < 0.001), and 50% of the total study population gained at least one NYHA class. After 12 months of treatment, 80% of the patients were in NYHA class I. Blood pressure decreased significantly with a good tolerance at 6 months and then remained stable. After 12 months of treatment, significant reductions of LV end-diastolic diameter (61.4 +/- 5.3 vs. 64.5 +/- 6.5 mm; p = 0.001) and LV mass index (143.3 +/- 21.5 vs. 164.2 +/- 40.2 g/m2; p < 0.001) were observed, reflecting a positive effect on the LV remodelling process. Despite some limitations, because it is of an open-label design with a small number of patients, our study found significant differences in clinical and objective parameters in heart failure patients switched from enalapril to perindopril. The prognostic significance of these findings remains to be investigated.