加藤 まり子¹, 宮沢 総介², 成味 純², 宮田 晴夫², 鈴木 厚子², 杉浦 徹², 横井 奈穂子¹, 田中 一江¹, 福田 淳¹

Mariko KATO¹, Sosuke MIYAZAWA², Jun NARUMI², Haruo MIYATA², Atsuko SUZUKI², Toru SUGIURA², Naoko YOKOI¹, Kazue TANAKA¹, Atsushi FUKUDA¹

¹聖隷三方原病院臨床検査部, ²聖隷三方原病院循環器科　

¹Department of Clinical Laboratory, Seirei Mikatabara General Hospital, ²Department of Cardiology, Seirei Mikatabara General Hospital

キーワード : Acute myocardial infarction , Atrial fibrillation , Echocardiography, Left atrial ball thrombus, Normal mitral valve

We report the case of an 82-year-old man with a left atrial ball thrombus. He was admitted because of nausea and vomiting. Electrocardiography showed atrial fibrillation and elevated ST segments in leads Ⅱ, Ⅲ, and aVF resulting from inferior wall myocardial infarction. Echocardiography showed a large ball thrombus in the left atrium, as well as akinetic motion of the inferior wall. The thrombus moved freely in the left atrium and strangulated into the mitral valve orifice in the end-diastolic phase. The thrombus was kept in the upper space of the left atrium by having the patient on his left side. The patient died from acute renal failure two months after admission. At autopsy, a reddish, smooth-surfaced ball thrombus was found in the left atrium. To our knowledge, cases with left atrial ball thrombus without mitral valve disease have rarely been reported.