Significance of prolonged left ventricular wall motion abnormalities after exercise echocardiography following non-Q-wave acute myocardial infarction.

Exercise echocardiography was used to assess myocardial ischemia after non-Q-wave acute myocardial infarction in 40 consecutive patients. Resting parasternal long- and short-axis views and apical 4- and 2-chamber views were recorded, digitized, and stored. A maximal symptom-limited exercise test was performed within 21 days (mean 17.7 +/- 3) using a cycle ergometer with continuous monitoring and the echocardiogram was repeated in the same views. Resting and exercise echocardiograms were then compared. Coronary angiography was performed in all patients within 21 days of exercise echocardiography. Stenosis in > or =50% of the lumen diameter was considered significant. Of the 40 patients studied, 29 (72%) had continuing angina and 11 (28%) had no angina. Eighteen patients (62%) with angina developed angina during exercise testing and 19 (65%) developed ST-segment depression. In patients without angina, 1 (9%) developed postexercise angina and 2 (18%) developed ST-segment depression. The mean wall motion score index after exercise increased from 1.2 +/- 0.3 to 1.8 +/- 0.4 in patients with continuing angina (p <0.001) and from 1.2 +/- 0.3 to 1.4 +/- 0.3 in patients without angina (p = NS). Prolonged wall motion abnormalities lasting >20 minutes persisted in > or =1 segment in 27 of 29 patients (93%) with angina or in 2 of 1 1 patients (18%) without angina (p <0.001). Patients with continued angina had predominantly 3-vessel coronary artery disease (22 of 29 [76%]) or 2-vessel disease (7 of 29 [24%]), and those without angina had 1-vessel disease (6 of 11 [55%]) or 2-vessel disease (4 of 11 [36%]). One patient had 3-vessel disease. The duration of wall motion abnormality demonstrated a significant relation to 2- and 3-vessel coronary artery disease (p <0.001). Thus, patients with non-Q-wave acute myocardial infarction had a high incidence of multivessel coronary disease not necessarily detected on routine exercise testing. There was also a significant incidence of prolonged wall motion abnormality.