Usefulness of ejection fraction response to exercise one month after acute myocardial infarction in predicting coronary anatomy and prognosis.

The prognostic value of left ventricular (LV) ejection fraction (EF) measured during maximal exercise testing early after acute myocardial infarction (AMI) was assessed in 75 patients, aged 65 years or younger, a mean of 36 days after AMI. At follow-up for a mean 12 months (range 6 to 26), medical complications developed in 15 patients: cardiac death in 5, ventricular fibrillation in 1, reinfarction in 2, unstable angina in 5, and severe cardiac failure in 2. Seven other patients underwent coronary artery bypass grafting for severe angina. When LVEF less than 50% at rest was compared with LVEF of 50% or more, the 2-year life-table survival free of complications was 54 +/- 21% compared with 84 +/- 19% (p less than 0.05). When exercise LVEF less than 50% was compared with LVEF of 50% or more, the 2-year survival rate free of medical complication was 42 +/- 32% compared with 83 +/- 20% (p less than 0.05). LVEF change from rest to exercise was not related to prognosis. Patients with combined medical and surgical events tended to have lower rest and exercise LVEFs, but changes in LVEF during exercise were again unrelated to prognosis. Sixty-five patients underwent coronary arteriography. After inferior AMI the mean LVEF was lower in those with multivessel than in those with 1-vessel coronary artery disease at rest (47 +/- 13% vs 59 +/- 7%, p less than 0.005) and during exercise (47 +/- 13% vs 59 +/- 9%, p less than 0.005); however, the change in LVEF during exercise was not related to coronary anatomy anatomy.(ABSTRACT TRUNCATED AT 250 WORDS)