In this follow-up analysis of CAPRICORN, investigators found that carvedilol improves clinical outcome in patients with left ventricular dysfunction after acute myocardial infarction. These findings were consistent regardless of patient age, sex, history of angina, and other factors. These findings suggest high-risk patients with left ventricular dysfunction will benefit if this beta-blocker is included in post-myocardial infarction therapy.

Previous studies have shown that beta blockade after myocardial infarction provides long-term benefits including reduced rates of mortality, sudden death and non-fatal reinfarction. However, investigators conducted these trials in the treatment era before thrombolysis and angiotensin-converting enzyme inhibitors. Furthermore, they did not measure left ventricular function and typically excluded heart failure patients.

Dr. Sharpe presented new data regarding carvedilol efficacy on morbidity and mortality in left ventricular dysfunction patients who had a myocardial infarction. They treated these patients according to a protocol that required use of an angiotensin-converting enzyme inhibitor.

The data comes from the double blind, randomized, placebo-controlled CAPRICORN trial. This trial included nearly 2,000 patients with acute myocardial infarction and a left ventricular ejection fraction of 40% or less. Almost all of them received angiotensin-converting enzyme inhibitors.

As reported in May 2001 in The Lancet, carvedilol reduced all-cause mortality by 23% (from 15% to 12%). The beta-blocker also reduced the composite of all cause mortality and cardiovascular hospitalizations by 8%. These were the primary endpoints of the study.

In an oral presentation, Dr. Sharpe revealed that carvedilol also reduces cardiovascular mortality by 25% (from 14% to 11%). Recurrent myocardial infarction was halved from 6% to 3%.

The combined endpoint of all major cardiovascular events (cardiovascular death, non-fatal myocardial infarction, hospitalization for heart failure) was 19% lower in the group of patients treated with carvedilol.

Patient benefit was consistent regardless of age, sex, ejection fraction, location of myocardial infarction, previous history of angina or myocardial infarction, presence of diabetes or heart failure, and other factors.

In addition, Dr. Sharpe reported that treating 43 of these high risk left ventricular dysfunction patients would prevent one death per year. The number needed to treat for ACE inhibitors alone is similar to this in this patient group, but in CAPRICORN this benefit was additive to the ACE inhibitor benefit.

One attendee asked whether these findings suggest a class effect for beta-blockers in this patient population. Dr. Sharpe did not rule out this possibility, but noted that data is available only to support the use of carvedilol in this situation.

CAPRICORN Sub-study Results: