西上 和宏, 吉川 純一, 吉田 清, 皆越 真一, 赤阪 隆史, 赤土 正洋, 山浦 泰子

Kazuhiro NISHIGAMI, Junichi YOSHIKAWA, Kiyoshi YOSHIDA, Shinichi MINAGOE, Takashi AKASAKA, Masahiro SHAKUDO, Yasuko YAMAURA

神戸中央市民病院循環器センター

Department of Cardiology, Kobe General Hospital

キーワード : mitral regurgitant orifice area, Doppler color proximal isovelocity surface area method, echocardiography, mitral regurgitation

Changes in the mitral regurgitant orifice area were measured in twelve patients with mitral regurgitation using the Doppler color proximal isovelocity surface area (PISA) method.
The instantaneous mitral regurgitant flow rate was calculated as PISA × isovelocity. PISA is given by: 2πr², where r is the aliasing radii calculated from color overlayed M-mode images. The regurgitant orifice area was calculated as instantaneous regurgitant flow rate divided by the velocity of the regurgitant jet measured by continuous wave Doppler at nine regurgitation times(T1, T2, T3, T4, T5, T6, T7, T8, T9).
Regurgitant orifice area at T2 was less than that at T1(pRegurgitant orifice area at T3 was less than that at T2(pRegurgitant orifice area at T4 was less than that at T3(pRegurgitant orifice area at T7 was larger than that at T6(pRegurgitant orifice area at T8 was larger than that at T7(pRegurgitant orifice area at T9 was larger than that at T8(pThus, the mitral regurgitant orifice area varied during systole. The mitral regurgitant orifice area decreased to 34% of its initial value during ventricular ejection and increased during ventricular isovolumetric relaxation.