抗血小板療法中に左房内巨大血栓を併発した肥大型閉塞性心筋症の1症例

A case of hypertrophic obstructive cardiomyopathy with left atrial giant thrombus during anti-platelet therapy

　心エコー法，CT法等の普及につれ心腔内血栓を発見する機会が多くなってきたが，左房内巨大血栓は稀な病態であり，かつほとんどが僧帽弁狭窄症（MS）に伴い，その他僧帽弁置換術後等にも散見されるが肥大型心筋症（HCM）に伴うものは極めて稀である。今回，我々はTIAの既往のため抗血小板療法を施されていたにもかかわらず左房内巨大血栓の発生を認めた肥大型閉塞性心筋症（HOCM）の1症例を経験したので若干の文献的考察を加えて報告する。

A case of a 77-year-old female with hypertrophic obstructive cardiomyopathy having the left atrial "giant" thrombus was reported ; the diagnosis of the localization and size of the thrombus was made by employing echocardiography and contrast enhance-ment computed tomography as well. The clinical record indicated that the thrombus formation, which happened in the course of the antiplatelet therapy, was to be considered due to the complicated condi-tion of the patient, i. e., the combination of atrial fibrillation, low cardiac output, enlargement of left atrium and left ventricular diastolic disfunction, which assumed to predispose the giant thrombus.Avoiding the surgical removal of the thrombus be-cause of the poor conditions of the patient, urokinase treatment was attempted, but not successful, which might be derived from the nature of the thrombus already organized. In general, left atrial giant throm-bus is very uncommon status ; if any, it is occasio-nally complicated with mitral stenosis. The case reported deems to be very rare, enough worthy to be reported.