経皮的冠動脈形成術（PTCA）における急性冠閉塞の臨床病理学的検討

Clinicopathologic study of acute coronary occlusion in percutaneous transluminal coronary angioplasty

　経皮的冠動脈形成術（PTCA）の施行中あるいは施行後の比較的早期に発生する冠動脈の閉塞（急性冠閉塞）は，PTCAの主要な合併症（心筋梗塞・緊急バイパス術・死亡）と関連する非常に重要な問題である^1）。しかしその発生機序や発生要因あるいはその対策については未解決の問題が多数残されている。本研究ではこれらの問題を明らかにするため，臨床例と剖検例を用いて検討した。

Twenty-four patients with acute coronary occlu-sion (ACO) within 24 hours after percutaneous transluminal coronary angioplasty (PTCA) were re-viewed and compared with a control group of 86 consecutive patients who underwent successful first PTCA and had no ACO.

ACO occurred within 40 min (mean 15.7 min) after PTCA in 22 patients and more than 12 hours in 2. The group with ACO had a significantly higher incidence of female (46% vs 23%), acute myocardial infarction (63% vs 35%), eccentric les-ions (73% vs 28%), tortuous lesions (30% vs 4%) and coronary dissection or intraluminal haziness (89% vs 34%). Luminal narrowing before and after PTCA was significantly higher in ACO group than in control group (93% and 56% vs 87% and 23%). Repeat PTCA was performed in 17 patients andwas successful in 13. Coronary bypass surgery was performed in 4 patients. Intracoronary urokinase was ineffective to ACO. In 3 autopsy cases dying 5, 14 and 17 days after PTCA, large extent of in-timal tears and thrombus in the space of tears and the lumens were observed.

These results suggest that coronary dissection chiefly contributes to ACO and coronary thrombosis is superimposed for a secondary event in most of cases with ACO.