Pathogenesis of angina pectoris in patients with one-vessel disease: possible role of dynamic coronary obstruction.

We examined the pathogenesis of angina pectoris in 101 patients with one-vessel disease except those with 99% to 100% occlusion. The attacks could not be induced or could not be reproducibly induced by maximal treadmill exercise at the same hour of different days within a week period in 54 (53.5%) of the patients. In the 47 patients whose attacks were reproducibly induced by the exercise, propranolol, 80 mg orally, did not suppress the attacks in 41 (87.2%) of the patients. Diltiazem, 90 mg, and nifedipine, 20 mg given orally, suppressed the attacks completely in 39 (83.0%) of the 47 patients and in 36 (81.8%) of the 44 patients, respectively. Coronary arteriography showed that dynamic obstruction of the artery supplying the area of myocardium represented by ST segment deviation appeared during the attacks and disappeared with subsidence of the attacks in all 55 patients in whom coronary arteriography was done during the attack. We conclude that angina pectoris is usually caused not by increased myocardial oxygen demand but by dynamic coronary obstruction or by a combination of both in most patients with one-vessel disease.