Effects of enalapril on left ventricular function and exercise performance after a first acute myocardial infarction. The EDEN Study Investigators

A systematic review: Effect of angiotensin converting enzyme inhibition on left ventricular volumes and ejection fraction in patients with a myocardial infarction and in patients with left ventricular dysfunction

BACKGROUND AND AIM

To summarize and quantify results of echocardiographic studies examining the effect of angiotensin converting enzyme (ACE) inhibition on left ventricular remodelling in patients with acute myocardial infarction (MI) and in patients with left ventricular systolic dysfunction (LVSD).

METHODS

Systematic review of the literature and meta-analysis of eligible studies providing data on end-diastolic and end-systolic volumes and left ventricular ejection fraction (LVEF) were performed.

RESULTS

Data from 16 eligible studies were meta-analysed. The results of studies including patients with MI and preserved LVEF (>45%) showed no significant benefit of ACE inhibition. Results of studies/subgroups with mean LVEF < or =45% demonstrated significant differences in diastolic and systolic volumes of 3.0 (0.1, 6.0) ml and 2.25 (0.04, 4.4) ml in short-term (4-14 weeks) follow-up in favour of ACE inhibitor, p=0.041 and p=0.046 respectively. In the long-term (6-12 months) follow-up, the differences in diastolic and systolic volumes were 4.2 (0.98, 7.4) ml and 3.3 (0.9, 5.8) ml in favour of ACE inhibitor, p=0.01 and p=0.007 respectively. LVEF improved in both short and long-term follow-up, p=0.034 and p=0.021, respectively.

CONCLUSION

Chronic use of ACE inhibition has a small but sustained and beneficial effect on remodelling in patients with myocardial infarction and patients with chronic left ventricular dysfunction.

Effects of early and late administration of angiotensin-converting enzyme inhibitors on mortality after myocardial infarction

BACKGROUND

Clinical trials demonstrating that angiotensin-converting enzyme (ACE) inhibitors reduce mortality when prescribed following myocardial infarction have focused on either early or late administration. It is unclear what the overall mortality benefits are and how long they last.

METHODS

We identified trials of ACE inhibitor therapy after myocardial infarction that were published between 1987 and 2002. Studies were included if they were randomized placebo-controlled trials with follow-up of at least 1 month. Separate analyses were performed for trials of therapy initiated within 48 hours of infarction (early administration) or initiated more than 48 hours after infarction (late administration). The Yusuf-Peto modification of the Mantel-Haenszel method was used to obtain summary odds ratios for mortality.

RESULTS

Twenty-two trials (14 early administration, 8 late administration) met the inclusion criteria. Early administration of ACE inhibitors was associated with a slight reduction in 1-month mortality (odds ratio [OR] = 0.93; 95% confidence interval [CI]: 0.88 to 0.97) and a much larger reduction in 1-year mortality (OR = 0.68; 95% CI: 0.54 to 0.87). Late therapy was associated with significant reductions in 1-year mortality (OR = 0.84; 95% CI: 0.73 to 0.97), 2-year mortality (OR = 0.75; 95% CI: 0.67 to 0.85), and 3-year mortality (OR = 0.74; 95% CI: 0.65 to 0.84).

CONCLUSION

Both early and late administration of ACE inhibitor therapy are associated with lower mortality following myocardial infarction, with the largest benefits observed with long-term mortality.

Drug Therapy for Prevention of Recurrent Myocardial Infarction

OBJECTIVE

To provide an evidence-based overview of drug treatment for long-term secondary prevention of myocardial infarction (MI).

DATA SOURCES

We conducted searches of MEDLINE (1966-August 2002), the Cochrane Controlled Trial Register, and the reference list of each identified study.

STUDY SELECTION/DATA EXTRACTION

Trials and meta-analyses were included using the following criteria: (1) randomized trials, (2) description of identification procedure, inclusion criteria, outcome measures, and statistical methods, (3) confirmed MIs, (4) treatment continued for at least 1 month, and (5) all-cause mortality as primary outcome; other events as secondary outcomes. All authors interpreted the results from trials that met the inclusion criteria.

DATA SYNTHESIS

In randomized clinical trials, low-dose aspirin, high-intensity oral anticoagulants, beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, and statins decreased the risk of mortality and reinfarction after MI. Randomized clinical trials using calcium-channel blockers, antiarrhythmics, and hormone replacement therapy did not show benefits in patients with prior MI. Effects of the combined use of aspirin or oral anticoagulants with beta-blockers or ACE inhibitors plus statins must be derived from subgroup analysis of trials, but seem to be beneficial.

CONCLUSIONS

The use of at least aspirin or an oral anticoagulant, a beta-blocker or an ACE inhibitor, plus a statin should be incorporated in the treatment routine. Clopidogrel treatment might be an alternative to aspirin. Standard addition of a beta-blocker to ACE inhibitor-treated patients without reduced left-ventricular ejection fraction seems to be untimely.

Effect of angiotensin converting enzyme inhibition on sudden cardiac death in patients following acute myocardial infarction. A meta-analysis of randomized clinical trials

Estimate the effect of angiotensin converting enzyme (ACE) inhibitors on the risk of sudden cardiac death (SCD) following myocardial infarction (MI).

BACKGROUND

Trials in post-MI patients have shown that ACE inhibitor therapy reduces mortality. However, the effect on SCD as a mechanism has not been clarified.

METHODS

Trials of ACE inhibitor therapy following MI reported between January, 1978 and August, 1997 were identified. Studies were included if they met the following criteria: 1) randomized comparison of ACE inhibitor to placebo within 14 days of MI; 2) study duration/blinded follow-up of > or =6 weeks; 3) the number of deaths and modes of death were reported or could be obtained from the investigators.

RESULTS

We identified 374 candidate articles, of which 15 met the inclusion criteria. The 15 trials included 15,104 patients, 2,356 of whom died. Most (87%) fatalities were cardiovascular and 900 were SCDs. A significant reduction in SCD risk or a trend towards this was observed in all of the larger (N > 500) trials. Overall, ACE inhibitor therapy resulted in significant reductions in risk of death (random effects odds ratio [OR] = 0.83; 95% confidence interval [CI] 0.71-0.97), cardiovascular death (OR = 0.82; 95% CI 0.69-0.97) and SCD (OR = 0.80; 95% CI 0.70-0.92).

CONCLUSIONS

This analysis is consistent with prior reports showing that ACE inhibitors decrease the risk of death following a recent MI by reducing cardiovascular mortality. Moreover, this analysis suggests that a reduction in SCD risk with ACE inhibitors is an important component of this survival benefit.