松浦 秀哲¹, 山田 晶², 杉本 邦彦¹, 大平 佳美¹, 高橋 礼子¹, 杉本 恵子³, 尾崎 行男², 岩瀬 正嗣⁴, 石川 隆志¹, 石井 潤一¹

Hideaki MATSUURA¹, Akira YAMADA², Kunihiko SUGIMOTO¹, Yoshimi OHIRA¹, Ayako TAKAHASHI¹, Keiko SUGIMOTO³, Yukio OZAKI², Masatsugu IWASE⁴, Takashi ISHIKAWA¹, Junichi ISHII¹

¹藤田保健衛生大学病院臨床検査部, ²藤田保健衛生大学医学部循環器内科, ³藤田保健衛生大学医療科学部臨床生理学, ⁴藤田保健衛生大学医療科学部医療経営情報学科

¹Fujita Health University Hospital, Clinical Laboratory, ²Fujita Health University School of Medicine, Division of Cardiology, ³Fujita Health University School of Health Sciences, Department of Clinical Physiology, ⁴Fujita Health University School of Health Sciences, Faculty of Medical Management and Information Science

キーワード : echocardiography, Doppler, left atrial volume index, late diastolic annular velocity, coronary artery disease

目的：左房容積係数（left atrial volume index: LAVI）は，左室拡張能の低下に伴う左室充満圧上昇により増大することに加えて，急性心筋梗塞患者の予後評価に有効であることが報告されている．また，組織ドプラエコー法を用いた僧帽弁輪部心房収縮速度波（A’）が，心房機能を反映することが報告されている．今回A’により，心事故発生を層別化出来るか否かを，左房拡大の有無を踏まえて検討を行った．対象と方法：対象は，当院CCUに入院した急性冠症候群（acute coronary syndrome: ACS）患者のうち，心房細動，心房粗動及び中等度以上の僧帽弁疾患を除外した連続212例（平均年齢64歳，男性166例）．心臓死及び心不全による再入院を心事故と定義して，平均508日間の経過観察を行った．対象を左房拡大（LAVI≥32ml/m²）62例と非拡大150例の2群に分類し，検討した．結果：経過観察期間中に17例（死亡8例，心不全による再入院9例）の心事故が発生した．ROC曲線からA’のカットオフ値を10.7 cm/secに設定した．全例及び左房拡大例においては，A’≥10.7cm/secの群で心事故回避率が有意に高値であった．結論：左房拡大を伴うACS患者において，A’は心事故予測に有用である．

Purpose: Left atrial (LA) volume index (LAVI) has been reported to reflect left ventricular (LV) diastolic dysfunction and predict cardiac events in patients with coronary artery disease (CAD). Late diastolic mitral annular velocity (A’) has been shown to correlate well with LA function and LV filling pressure. We hypothesized that A’ could be a useful predictor of mortality and rehospitalization due to heart failure (HF) in CAD patients with dilated LA volume. Subjects and Methods: This study included 212 patients (mean age: 64 years, 166 men) who were admitted to the coronary care unit at our hospital due to acute coronary syndrome (ACS). They underwent echocardiography including tissue Doppler imaging (TDI). None of them had atrial fibrillation and atrial flutter or more than moderate mitral valvular disease. The primary study endpoints were mortality and rehospitalization due to HF. Results and Discussion: During a mean follow-up of 508 days, eight patients died and nine patients were rehospitalized due to HF. According to a previous report, the patients were divided into two groups. Group A: LAVI≥32 ml/m² (n=62) and Group B: LAVI〈32 ml/m² (n=150). Receiver operator curve analysis revealed that A’≥10.7 cm/s was the optimal cut-off value to predict mortality and rehospitalization due to HF in Group A. In Group A, patients with A’≥10.7 cm/sec showed a significantly lower incidence of cardiac events than those with A’〈10.7 cm/sec (log-rank, p=0.0019). However, A’ could not be a predictor of events in Group B. Conclusion: A’ could be a useful predictor of mortality and rehospitalization due to HF in ACS patients with large LAVI.