Long term use of enalapril in the treatment of patients with congestive heart failure

Effect of angiotensin-converting enzyme inhibition on functional class in patients with left ventricular systolic dysfunction-a meta-analysis

BACKGROUND

The effect of angiotensin converting enzyme (ACE) inhibitors on symptoms in patients with left ventricular systolic dysfunction (LVSD) is controversial.

AIMS

To perform a meta-analysis of studies evaluating effect of ACE inhibitors on New York Heart Association (NYHA) class in patients with LVSD.

METHODS

Individual data from 10389 patients in NYHA classes I-IV from four large long-term studies (2-4-year follow-up) and summary data from 2302 patients in NYHA classes II-IV from 16 short-term studies (3 months follow-up) were meta-analysed to assess changes in NYHA class.

RESULTS

The large long-term studies showed a significant improvement in the worst NYHA classes (classes II-IV compared to class I) in the ACE inhibitor arm versus placebo, odds ratio (OR) = 0.875 (0.811-0.943) p = 0.0005. This effect was only present in studies which included patients with chronic heart failure and was particularly pronounced on deterioration to the worst NYHA class IV, OR = 0.66 (0.52-0.84) p = 0.001. There was no effect in the studies which included patients after myocardial infarction. The short-term chronic heart failure studies showed a significant improvement in NYHA class; OR for improvement of at least one NYHA class was 2.11 (1.48-2.98, 95% CI) p < 0.0001.

CONCLUSION

ACE inhibition significantly improves symptomatic status measured as NYHA classification in patients with chronic heart failure.

A meta-analysis of the effect of angiotensin-converting enzyme inhibitors on functional capacity in patients with symptomatic left ventricular systolic dysfunction

AIM

To determine by meta-analysis whether angiotensin-converting enzyme (ACE) inhibitors improve exercise tolerance in patients with symptomatic left ventricular systolic dysfunction (LVSD).

METHODS AND RESULTS

After literature search 13 multi-centre double blind parallel group trials that evaluated the effect of ACE inhibitors vs. placebo on exercise duration were selected. Ninety-four percent of patients were in New York Heart Association class II-IV. The studies were combined using the Cochrane meta-analysis program (Review manager version 4.1). Analyses according to treatment period, exercise protocols and publication periods were performed. Treatment with ACE inhibitor over 4-12 weeks resulted in a beneficial effect on exercise duration (P=0.003 and P=0.0008 for 4- and 12-weeks treatment, respectively), but the magnitude of improvements did not exceed 30 s corresponding to only 5% compared with placebo.

CONCLUSION

In addition to the pronounced effect on mortality and morbidity in patients with symptomatic LVSD, ACE inhibitors have improving effect on functional capacity measured as exercise tolerance time.