Correlation of "critical" left coronary artery lesions with positive submaximal exercise tests in patients with chest pain.

This study correlates the anatomic pathologic coronary anatomy found by arteriography in each of three groups of symptomatic patients, all with coronary artery disease, divided according to the magnitude of ST-segment depression after an adequate submaximal treadmill exercise test. Group I consists of 45 patients with ST-segement depression of 2 mm. or more, Group II of 31 patients with ST-segment depression between 1.0 and 1.9 mm., and Group III, 30 patients with 0 to 0.9 mm. ST-segment depression. Seventy-five per cent of the patients in Group I had critical lesions defined as (1) 75 per cent or greater narrowing of left main coronary artery (LMCA), (2) 75 per cent or greater obstructive left anterior descending and left circumflex coronary artery both proximal to any major branching, the so-called left main equivalent (LME) lesions, and (3) 90 per cent or more obstruction of the left anterior descending coronary proximal to any major branches. Of patients in Group I, 24 PER CENT Had LMCA lesions, 29 per cent had LAD lesions. Eight-two per cent of Group I patients had two- or three-vessel disease. All patients with LMCA lesions had 2 mm. or more ST-segment depression. Over 95 per cent of patients with "critical" lesions is less than 5 per cent in the presence of an adequate aubmaximal treadmill test that shows less than 1 mm. of ST-segment depression, it is concluded that in such patients with medically controllable angina, coronary arteriography is not necessary.