真田 純一, 尾立 源晴, 山王 和寿, 小牧 伸一郎, 常盤 二起子, 寺田 浩和, 加倉 秀章, 小寺 顕一, 田中 康博, 有馬 暉勝

Junichi SANADA, Motoharu ODACHI, Kazuhisa SANNOU, Shinichiro KOMAKI, Fukiko TOKIWA, Hiroaki TERADA, Hideaki KAKURA, Kenichi KODERA, Yasuhiro TANAKA, Terukatsu ARIMA

鹿児島大学医学部付属病院第2内科

Second Department of Internal Medicine Kagoshima University Faculty of Medicine

キーワード : Color Doppler echocardiography　, Mitral regurgitation , Pulsed Doppler echocardiography, Ultrasound diagnosis, Ultrasound

To assess the usefulness of analyzing mitral regurgitant flow at the left ventricular side of the mitral orifice to grade severity of mitral regurgitation (MR), pulsed Doppler echocardiography (PDE) and color Doppler echocardiography (CDE) were performed in 111 consecutive cases (mean age, 59±10 years) with MR to determine its severity by left ventriculography within 7 days before or after echocardiography. Sellers' classification indicated grade I in 58 cases, grade Ⅱ in 25 cases, grade Ⅲ in 17 cases, and grade Ⅳ in 11 cases. PDE detected MR flow in the left ventricle in 2 (3%) cases in grade Ⅰ, 14 (56%) cases in grade Ⅱ, 17 (100%) cases in grade Ⅲ, and 11(100%) cases in grade Ⅳ. Laminar flow (showing a narrow-band spectrum with open area 1/2 ≤ of peak velocity and velocity peak at late-systole continuing over the second heart sound) was observed in none of those cases in grade Ⅰ, 1 (4%) of those in grade Ⅱ, 14 (82%) of those in grade Ⅲ, and 10 (91%) of those in grade Ⅳ. CDE showed acceleration flow in 22 (38%) cases in grade Ⅰ, 17 (68%) cases in grade Ⅱ, 17 (100%) cases in grade Ⅲ, and 11(100%) cases in grade Ⅳ. Large acceleration flow (1.0 cm²≤) was detected in none of these cases in grade Ⅰ, 2 (8%) in grade Ⅱ, 11 (65%) in grade Ⅲ, and 8 (73%) in grade Ⅳ. Based on detection of laminar flow on PDE and large acceleration flow on CDE, the sensitivity of PDE and CDE in diagnosing severe MR (grade Ⅲ≤) was 86% vs 68%; specificity, 99% vs 98%; predictive value, 96% VS 90%; and accuracy, 95% vs 90%, respectively. The usefulness of quantifying MR at the left ventricular side of the mitral orifice by CDE to grade its severity has been reported; however, the process is affected by such factors as use of an inappropriate gain setting, and difficulty in separating MR from ejection flow of flow-area planimetry method or the time-consuming proximal isovelocity surface-area method. Here we show that use of PDE to detect laminar flow in severe MR appears to involve fewer of these limitations. We conclude that use of PDE to analyze MR flow at the left ventricular side of the mitral orifice is useful for rapid and accurate grading of severity of MR, especially when combined with CDE, which is highly sensitive to MR.