急性心筋梗塞におけるカテーテルによる冠動脈再開通術の効果

Effects of percutaneous transluminal coronary recanalization in acute myocardial infarction

　1981年Rentropら^1）およびGanzら^2）によって広く世界に紹介されたpercutaneous transluminal coronary　recanalization （以下PTCR）はその後急速に普及し，急性心筋梗塞に対する最も重要な治療法の一つとなりつつある。欧米におけるPTCRの研究はすべてストレプトキナーゼ製剤を用いたもので，この治療を行うことによりわずかではあるが有意に左室機能が改善するという多くの報告がある^3〜10）。

　一方，本邦においてはウロキナーゼ（以下UK）が主に使用されており，ストレプトキナーゼと同様に閉塞冠動脈を再開通することができることはすでに認められている^11〜13）。しかしPTCRにより急性期から慢性期にかけて左室機能がどの程度改善するのかという点についてはまだ十分に検討されていないのが現状である。

Coronary arteriographies were performed in 25 consecutive patients with acute myocardial infarc-tion 4.14-1.8 hours (mean±SD) after the onset of symptoms. Twenty patients had total occlusion or subtotal occlusion with poor distal flow of an infarct-related coronary artery, while remaining 5 had severe proximal stenosis without poor distal flow. In 14 patients (70%), the occluded coronary artery was successfully recanalized by an intracoronary infusion of nitroglycerin or urokinase. All patients were administered GIK solution containing 313 gm glucose, 40 unit regular insulin and 50 mEq potassium per liter at 67 ml per hour for 76 hours. Repeat arteriography 30-56 days later revealed a patent coronary artery in 8 (Group A) of 13 successfully recanalized patients.

The left ventricular ejection fraction had signi-ficantly improved in Group A, from 54±12% to 74±9% (p<0.01). In contrast, the ejection fraction did not show significant increase in patients with unsuccessful recanalization or late reocclusion, from 43118% to 46±14% (p>0.10).

These data suggest that successful early recanalization with sustained patency of an infarct-related coronary artery has a beneficial effect on the extent of myocardial necrosis as estimated from contrast left ventriculogram. And we belive that GIK solution can enhance the beneficial effect of PTCR on left ventricular function in acute myocardial infarction.