山田 聡¹, 岩野 弘幸¹, 大手 信之², 瀬尾 由広³, 山田 博胤⁴, 石津 智子³, 楠瀬 賢也⁴, 若見 和明², 三神 大世⁵, 筒井 裕之¹

Satoshi YAMADA¹, Hiroyuki IWANO¹, Nobuyuki OHTE², Yoshihiro SEO³, Hirotsugu YAMADA⁴, Tomoko ISHIZU³, Kenya KUSUNOSE⁴, Kazuaki WAKAMI², Taisei MIKAMI⁵, Hiroyuki TSUTSUI¹

¹北海道大学大学院医学研究科循環病態内科学, ²名古屋市立大学大学院医学研究科心臓・腎高血圧内科学, ³筑波大学医学医療系循環器内科, ⁴徳島大学病院循環器内科, ⁵北海道大学大学院保健科学研究院

¹Department of Cardiovascular Medicine, Hokkaido University Graduate School of Medicine, ²Department of Cardio-Renal Medicine and Hypertension, Nagoya City University Graduate School of Medical Sciences, ³Cardiovascular Division, Faculty of Medicine, University of Tsukuba, ⁴Department of Cardiovascular Medicine, Tokushima University Hospital, ⁵Faculty of Health Sciences, Hokkaido University

キーワード : diastolic function, e´, echocardiography, left ventricular filling pressure, relaxation

目的：拡張早期僧帽弁輪運動速度（e´）は左室弛緩能の指標，左室流入血流拡張早期波高（E）のe´に対する比（E/e´）は左室充満圧の指標として普及している．しかし，最近，これらの指標の精度を疑問視する成績が幾つか報告されている．そこで，多施設共同研究SMAPを行い，拡張機能指標の診断精度を再検討した．対象と方法：4施設からの52例において，micromanometer付きカテーテルを用いて左室圧を記録し，圧下降脚の時定数（τ）と平均拡張期圧（LVMDP）を計測した．心エコー図法による左室拡張機能指標を計測した．結果と考察：e´は弛緩障害の有無で有意差を認めなかった．τ（48±11 msec）とe´（r=-0.30, p=0.03），τと肺静脈血流の拡張期波減速時間（r=0.40, p=0.02）の間にはまばらだが有意な相関を認めた．E/e´は充満圧上昇の有無で有意差を認めなかった．LVMDP（8.3±6.1 mmHg）はE/A（r=0.47, p=0.001）とは相関したが，E/e´（r=0.27, p=0.053）とは相関しなかった．結論：本邦初の多施設共同研究により，種々の器質的心疾患を含んだ対象における左室弛緩能と充満圧の推定に関して，e´とE/e´には限界があることが示唆された．さらに，e´とE/e´には，基本的な拡張機能指標である左室流入血流や肺静脈血流の指標と比較して，優位性を認めなかった．

Purpose: Mitral annular early-diastolic velocity (e´) and the early transmitral velocity to e´ ratio (E/e´) have been widely used as indexes of left ventricular (LV) relaxation and filling pressure, respectively. There are, however, a number of clinical settings in which e´ and E/e´ may not be reliable. We thus conducted a multicenter study in Japan (SMAP) to determine the accuracy of echocardiographic indexes of LV relaxation and filling pressure. Subjects and Methods: In 52 patients with various structural heart diseases from four institutions, time constant of LV pressure decay (τ) and LV mean diastolic pressure (LVMDP) were measured using a micromanometer-tipped catheter. Echocardiographic diastolic parameters were also measured. Results and Discussion: There was no difference in e´ between patients with and without abnormal relaxation. There was a weak, but significant, correlation between τ (48±11 msec) and e´ (r=-0.30, p=0.03), or deceleration time of pulmonary venous D wave (r=0.40, p=0.02). There was no difference in E/e´ between patients with and without elevated LV filling pressure. LVMDP (8.3±6.1 mmHg) significantly correlated with transmitral E/A (r=0.47, p=0.001), but not with E/e´ (r=0.27, p=0.053). Conclusion: The multicenter study in Japan demonstrated that e´ and E/e´ might be of limited use for estimating LV relaxation and filling pressure in patients with various structural heart diseases. Furthermore, e´ and E/e´ were not superior to the conventional indexes of LV inflow or pulmonary venous flow.