The effects of brief periods of major coronary artery occlusion on global and regional peak left ventricular (LV) filling rates were studied during angioplasty in 10 patients. No patient had had a previous myocardial infarction. High-fidelity LV pressure and volume were determined by angiography before and 20 and 50 seconds after the onset of transluminal coronary occlusion and soon after the last balloon inflation. Segmental wall motion was analyzed frame by frame along 20 hemiaxes. Global peak filling rate decreased significantly both after 20 (29%, p <0.05) and 50 seconds (27%, p <0.05) from the onset of the occlusion. The term ΣΔt1 was defined as the sum of the absolute values of the time differences from the occurrence of global peak filling rate and the segmental peak filling rate in 20 segments. This variable increased significantly during both periods of transluminal occlusion (by 73% and by 72% [both p <0.005], respectively), indicating asynchrony in the occurrence of regional peak filling rate. Simultaneously, the sum of intervals between aortic valve closure (end systole) and occurrence of peak segmental shortening, ΣΔt2, measured in the 20 segments, increased by 63% after 20 seconds and by 87% after 50 seconds (both p <0.005), showing major asynchrony in segmental contraction. A significant negative correlation was found between global peak filling rate and both ΣΔt1 and ΣΔt2 (r = 0.64, p <0.001 and r = 0.70, p <0.0001, respectively). Our findings suggest that during coronary transluminal occlusion, early asynchrony in regional peak filling rate occurs that appears to be related to delayed and asynchronous peak segmental shortening.
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