村上 弘則¹, 米倉 修二², 高橋 尚子², 橋本 暁佳², 長谷 守², 善岡 信博², 田中 繁道², 飯村 攻²

Hironori MURAKAMI¹, Shuji YONEKURA², Naoko TAKAHASHI², Akiyoshi HASHIMOTO², Mamoru HASE², Nobuhiro YOSHIOKA², Shigemichi TANAKA², Osamu IIMURA²

¹天使病院循環器内科, ²札幌医科大学第2内科

¹Department of Cardiology Tenshi Hospital, ²Second Department of Internal Medicine School of Medicine Sapporo Medical University

キーワード : Aging, Left atrial function

To assess the effects of aging on the left atrial contractile function, 170 normal subjects (84 males and 86 females; 40.0±16.9 years old) were analyzed echocardiographically. From an M-mode recording at the aortic root level, it was possible to examine the left atrial dimension index just prior to atrial contraction (DDal) as end-diastole, that after atrial contraction (DSal) as end-systole, maximum left atrial dimension index (DmaxI) and the interval between both timing (ETa). This made it possible to compute atrial filling fraction (AFF), the fractional shortening of the left atrium (FSa), and the mean velocity of circumferential fiber shortening of the left atrium (mVCFa). DDal, DSal, DmaxI and AFF increased with age, although aging did not alter the values of FSa and mVCFa. These findings suggest that left atrial contractility did not alter with age although the magnitude of preload recruitment to the left atrium increased with age for maintaining left ventricular filling.