Coronary hemodynamic findings during spontaneous angina in patients with variant angina.

Abstract

To define more completely regional coronary hemodynamic changes that occur during spontaneous angina pectoris in patients with variant angina, coronary sinus and great cardiac vein blood flow (CSF and GCVF) and aortic and left ventricular pressures were measured before and during spontaneous angina in 6 patients with variant angina. During spontaneous angina, ECG in 4 patients showed evidence for transient anterior regional ischemia (ST-T-wave changes in I, aVL, V1-6) and in 2 patients showed evidence for transient inferior regional ischemia (ST-T-wave changes in II, III, aVF). During spontaneous angina, CSF decreased in 5 of 6 patients (27 .+-. 10 ml/min, P < 0.05), compared with measurements made during a painfree interval. In all 4 patients with anterior ischemia, GCVF decreased 34 .+-. 13 ml/min (P < 0.05). In the 2 patients with inferior ischemia, GCVF was unchanged, but the difference between CSF and GCVF, an index of inferior regional blood flow, decreased 36 .+-. 20 ml/min during ischemia. Heart rate was not significantly different during angina and mean aortic pressure decreased in 3 patients, increased in 2 and was unchanged in the other. Left ventricular end-diastolic pressure increased 10 .+-. 2 mm Hg during spontaneous angina (P < 0.01). Blood flow to the ischemic region during spontaneous angina apparently is decreased in patients with variant angina. A functionally important decrease in regional myocardial O2 delivery apparently occurs in certain patients with variant angina coincident with angina and ST-segment and T-wave changes.