実験的急性虚血心におけるE−643の局所心筋動態および血行動態に及ぼす影響

Effects of E-643 on the regional myocardial function and hemodynamics in experimental acute coronary artery occlusion

　近年，急性心筋梗塞症にともなう左心不全に対して広く血管拡張剤療法が行われるようになり，その血行動態に及ぼす効果については多数の報告があるが，局所心筋動態に及ぼす効果については詳細な検討があまりなされていない。

　今回，我々は新しいquinazoline系化合物であるE—643を実験的急性虚血心に投与し，その血行動態および局所心筋動態に及ぼす効果について検討したので報告する。

We studied the effects of E-643, a new a₁-blocker on hemodynamics and regional myocardial function of the left ventricle in experimental acute coronary occlusion in dogs.

E-643 reduced mean aortic pressure by 18±2%, LVEDP (left ventricular end-diastolic pressure) by 22±5%, systemic vascular resistance by 26±2% and systolic pressure time index by 16±2%, and increased cardiac output by 13±3%. dp/dt/CDP was enhanced by 27±6% and time constant of isovolumic left ventricular pressure fall was shortened.

End-diastolic length decreased in all segments. In the normal and the marginal segments, myocardial shortening were increased in the first thirds of systole. In the ischemic segment, myocardial shortening was increased in the last thirds of systole.

These results indicated that E-643 reduced both preload and afterload, and improved cardiac pump function, regional myocardial function and left ventricular relaxation in ischemic myocardium, suggesting E-643 might be usefull for the treatment of acute myocardial infarction.