血行動態，冠循環および心筋代謝に対するNicardipine hydrochlorideの急性効果に関する検討

Acute effects of Nicardipine hydrochloride on hemodynamics, coronary circulation and myocardial metabolism

　Ca^＋＋拮抗剤であるNicardipine hydrochloride （1,4—dihydropyridine誘導体）の血行動態，冠循環および心筋代謝に及ぼす急性効果について，健常例10例を対象としてカテーテル法により検討を行った。

　Nicardipine 0.01mg／kgの静脈内投与により，平均大動脈圧の低下と冠静脈洞血流量の増加がみられ，全身血管抵抗および冠血管抵抗は共に有意に減少した。左心室拡張末期圧は軽度ながら有意に増加した。また，血圧降下により心拍数max dP／dt／Pの増加とともに心拍出量の増大が認められたが心筋酸素消費量と心筋乳酸摂取率は有意に変化しなかった。

We studied the acute effects of Nicardipine hydrochloride, a new Ca⁺⁺-antagonist, on hemo-dynamics and coronary circulation in healthy sub-jects.

Following intravenous administration, Nicardipine hydrochloride (0.01 mg/kg) decreased mean aortic pressure, mediated through a decrease in system ic vascular resistance and accompanied by increase in heart rate, max dP/dt/P and cardiac output. More-over, it increased coronary sinus flow through de-creasing coronary vascular resistance.

Although this drug produced these hemodynamic changes, it did not develop any change in myo-cardial lactate extraction ratio nor increase in myo-cardial oxygen consumption.

These results indicate that Nicardipine hydrochlo-ride is a favorable agent for afterload reducing therapy in patients with ischemic heart disease.