英文誌(2004-)
Original Article(原著)
(0515 - 0524)
同時2方向複数周波数超音波ドプラ法を用いた左室内3次元血流ベクトルの計測
Measurement of Left Ventricular Spatial Flow Vectors Using a Simultaneous Dual Frequency 2-D Echo Doppler Flowmeter
水重 克文, 森田 久樹, 中島 茂, 深田 英利, 平林 浩一, 大森 浩二, 松本 康彦, 舛形 尚, 千田 彰一, 松尾 裕英
Katsufumi MIZUSHIGE, Hisaki MORITA, Shigeru NAKAJIMA, Hidetoshi FUKADA, Koichi HIRABAYASHI, Koji OHMORI, Yasuhiko MATSUMOTO, Hisashi MASUGATA, Shoichi SENDA, Hirohide MATSUO
香川医科大学第二内科
Second Department of Internal Medicine, Kagawa Medical School
キーワード : Doppler echocardiography, flow vector, intracardiac blood flow
The purpose of this study is to measure 3-dimensional blood flow directions and accurate velocities (V) at various sites in the left ventricle (LV). The newly developed dual frequency 2-D echo Doppler flowmeter equipped with two transducers, each with different center frequencies of 3.5 MHz and 2.2 MHz, was used to measure the flow velocity components from different directions. We can estimate the 2-D flow vectors by composing velocity components along each Doppler beam. We measured 2-D flow vectors on the long axis and the perpendicular short axis images of the heart. By recomposing these two 2-D flow vectors spatially, we can estimate the 3-D flow vectors.
We studied 35 healthy subjects. The results were as follows. The LV rapid inflow (R), measured at the level of the mitral annulus, was directed a little to the posterior and left of the direction of the cardiac apex. V was 77±22 cm/sec. The LV inflow due to atrial contraction (A) was directed a little more to the posterior than was R, and the degree of leftward deviation of A was smaller than that of R. V was 50±13 cm/sec. We thought that the directional difference between R and A was caused by the change in the mitral annulus position due to phasic movements of the heart. The ejection flow measured in the middle of the LV outflow tract was directed a little posterior of parallel to the interventricular septal surface of the LV outflow tract and a little to the left. V was 69±23 cm/sec.
We could analyze the spatial blood flow vector, and measure the absolute flow velocity.