Oozing ruptureにて来院し，慢性期に真性か仮性か鑑別困難な心室瘤を認めた急性下壁心筋梗塞の1例

A Case of Oozing Rupture followed by a Pseudo-like Ventricular Aneurysm due to Acute Inferior Myocardial Infarction

　症例は61歳男性．呼吸困難と胸痛を主訴に来院．来院時心電図にてII,III,aV_F，V_4〜6で異常Q波とST上昇，心エコー検査にて左室下壁運動低下と一部モヤモヤエコーを含む心嚢液貯留を認めた．急性下壁心筋梗塞，左室自由壁破裂と診断した．緊急心臓カテーテル検査では，4PDの完全閉塞を認めた．第2病目心膜切開心嚢ドレナージを施行し，血性心嚢液約110mlを排液し，血行動態の安定を得た．慢性期に施行した左室造影，心エコー検査では下壁に真性か仮性か鑑別困難な心室瘤形成を認めた．心破裂のリスクを考慮し外科的治療を選択したが手術および病理所見は真性左室瘤であった．本症例はoozing typeの心破裂症例であるが，急性期に心エコー検査にて特徴的なモヤモヤエコーを含む高輝度心嚢液を認めたこと，また心嚢ドレナージのみで救命しえたこと，慢性期に真性か仮性か鑑別困難な心室瘤を認めたことなど貴重な経験と考えられたのでここに報告した．

A 61-year-old male was admitted to our hospital with chest pain and dyspnea. An electrocardiogram showed an abnormal Q wave and ST elevation at II, III, aV_F andV_4-6. The echocardiography showed hypokinesis at the left ventricular inferior wall and high echoic pericardial effusion. These findings suggested acute inferior myocar-dial infarction (MI) accompanied by left ventricular free wall rupture. The emergent coronary angiography demonstrated total occlusion of the posterodescending branch of the right coronary artery. One day after the patient's admission, pericardiocentesis was performed because of hemodynamic instability in spite of volume loading and low dose cathecolamine infusion.Hemodynamics improved as a result of the removal of 110 ml of bloody effusion. Left ventriculography and echocardiography performed 3 weeks after the onset of MI demonstrated an aneurysm at the inferior wall of the left ventricle. Because of difficulty with differentiation of true or false aneurysm, aneurysmectomy was perfor-med 1 month after onset, which showed that it was a true aneurysm. These findings suggest that: 1) an echocardiographic study should be performed before the initiation of reperfusion therapy for the treatment of acute myocardial infarction. 2) Oozing type free wall rupture may be partly stabilized by pericardiocentesis without an emergency operation. 3) Left ventricular aneurysm with a small mouth makes it dificult to differentiate between true or false aneurysm based on findings of echocardiography and/or left ventricurogra-phy, especially in cases of inferior aneurysms.