Influence of coronary occlusion during PTCA on end-systolic and end-diastolic pressure-volume relations in humans.

The influence of acute coronary occlusion on systolic and diastolic left ventricular pressure-volume relations was studied in 10 patients undergoing percutaneous transluminal coronary angioplasty (PTCA). Pressure-volume relations were obtained by conductance catheter and micromanometer techniques and with volume load altered by transient inferior vena caval occlusion. End-systolic and end-diastolic pressure-volume relations were obtained at baseline, during 60-90 seconds of ischemia, and at return to baseline after angioplasty balloon deflation. Coronary occlusion significantly altered systolic and diastolic chamber function. Systolic dysfunction was characterized by a reproducible rightward shift of the end-systolic pressure-volume relation (+25.4 +/- 18.4 ml) that was greater for proximal left anterior descending and circumflex coronary artery occlusions (+41 ml) than for distal or right coronary artery occlusions (+15.4 ml, p less than 0.05). Occlusion also lowered chamber systolic function indexes, su...