経静脈的線溶療法により救命し得た急性左主幹部動脈閉塞症の1例

A case with sudden obstruction of the left main coronary artery treated by intravenous thrombolysis

　左主幹部動脈の完全閉塞は極めて稀で，冠状動脈造影検査施行患者中0.04％〜0.3％の頻度でみられる^1〜3）。この極めて少ない原因として，完全閉塞を生じると短時間で致死的となることがあげられる。一方，最近急性心筋梗塞症に対しurokinaseの経静脈投与が再脚光をあびている。本例は左主幹部動脈に血栓による完全閉塞を生じ，心原性ショック状態となり，urokinaseの経静脈的投与にて救命し得た1例である。本邦内外を問わずかかる例をみないので報告する。

A 10-year-old man with severe chest pain and loss of consciousness was transferred to our hospital. He had a systolic blood pressure of 60mmHg and his electrocardiogram (ECG) showed ST elevation on leads I, AVL and V_2~6. 240,000 IU of urokinase were infused intravenously 50 minutes after the onset of chest pain. Immediately after it, a monitor ECG showed Torsade de pointes type ventricular arrhythmia. Sinus rhythm was restored after a direct-current cardiovarsion. Few minutes later, his chest pain was almost disappeared. Coronary angiographyshowed a small thrombus in the left main coronary artery (LMC). The dominant right coronary artery had no organic stenosis. At cardiac catheterization, the cardiac index was 7.6 l/min/m², the left ventri-cular enddiastolic pressure was 22mmHg. In the chronic state, two-dimensional echocardiograms showed hypokinesis of the anterior septal regions,and ²⁰¹Tl scintigrams showed no perfusion defects. This rare case suggest that in a case with acute LMC obstruction and cardiogenic shock, a high dose intravenous infusion of urokinase is effective not only for saving a life but also for salvaging injuried myocardium.