Angiographic characteristics of the infarct-related coronary artery in patients with angina pectoris after myocardial infarction.

To elucidate the pathophysiology of angina pectoris after myocardial infarction, we analyzed the coronary stenoses in 45 subjects (28 men, 17 women, aged 33 to 67 years) with recent (less than or equal to 60 days) infarction, significant narrowing of only the infarct-related artery, and residual anterograde flow in this artery. Postinfarction angina was absent in 19 (group I) and present in 26 (group II). The groups were similar in age, left ventricular function, incidence with which each coronary artery was involved, as well as stenosis diameter (1.0 +/- 0.3 vs 0.9 +/- 0.4 mm [mean +/- standard deviation], respectively, difference not significant), stenosis area (0.9 +/- 0.4 vs 0.8 +/- 0.8 mm2, respectively, difference not significant), percent diameter narrowing (65 +/- 5 vs 66 +/- 9, respectively, difference not significant), and stenosis eccentricity. However, those with postinfarction angina had longer stenoses (group I, 4.3 +/- 1.4 mm; group II, 10.3 +/- 4.0 mm; p less than 0.001). Thus, patients with postinfarction angina and residual anterograde flow in the infarct artery may have angina due to a marked reduction in anterograde flow, caused by a long stenosis. There is no apparent relation between stenosis eccentricity and postinfarction angina.