心筋梗塞症の左室拡張期特性と最大クレアチンキナーゼMB値との関係

Correlation of left ventricular diastolic property and peak creatine kinase MB isoenzyme activity in myocardial infarction

　急性期心筋梗塞の血清酵素学的分析は，心筋梗塞量の推定，心機能評価および予後判定に関して，実験的^1）および臨床的^2〜9）にすぐれた方法であることが明らかになっている。

　一方左室拡張期特性の重要性が認識されるにつれ，RIアンジオグラフィーの分野においても，左室拡張期心機能の研究^10〜14）が盛んに行われている。我々も拡張期全体の心機能を評価する目的で，逆方向性平衡時法を考案し，慢性期心筋梗塞を対象として，急速充満期および心房収縮期における左室充満様式の変化を報告^13）してきた。

Serial changes of serum creatine kinase-MB isoenzyme (CK-MB) activity have been used not only as diagnostic aids but also quantitative assess-ment of infarct size in acute myocardial infarction (MI). The purpose of this study was to evaluate the correlation of left ventricular (LV) diastolic property and peak CK-MB activity in patients (Pts) without prior MI.

Peak rapid filling rate (PRF) as an index of LV suction and peak atrial filling rate (PAF) as an index of left atrial booster pump functin were measured by means of backward method of Tc-99m equilibrium radionuclide angiocardiography from 15 normal controls and from 14 Pts after about one month from the onset of MI. CK-MB activity were determined from Pts with acute MI at admission and thereafter every four hour to obtain peak CK-MB activity. Peak CK-MB activity showed a close inverse correlation with ejection fraction (r=-0.792) and with PAF (r=-0.603). But there is a general relation between peak CK-MB activity and PAF (r=-0.447).

In conclusion enzymatic infarct size estimated utilizing peak CK-MB activity may be a reliable measure for assessing the left atrial booster pump function and LV contraction.