Dittmann H, Voelker W, Karsch K R, Seipel L
Medical Department III, University of Tuebingen, West Germany.
J Am Coll Cardiol. 1987 Oct;10(4):818-23. doi: 10.1016/s0735-1097(87)80275-9.
In 40 patients cardiac output was simultaneously determined by pulsed Doppler echocardiography and thermodilution (range 4.0 to 10.2 liters/min). The sample volume was located in the center of the mitral anulus, at the tips of the mitral leaflets and in the center of the aortic anulus. Circular cross-sectional areas of the mitral anulus, aortic anulus and aortic bulbus were calculated from M-mode and two-dimensional echocardiographic diameters. The varying short axis of the elliptical mitral opening area was obtained from the diastolic leaflet separation in the M-mode, and the long axis was derived from the maximal mitral orifice area or mitral anulus diameter. Cardiac output was calculated by multiplying time-velocity integrals with the different areas and heart rate. Doppler flow measurements correlated significantly with the thermodilution method (r = 0.79 to 0.93). Flow measurements at the aortic anulus were most accurate (r = 0.93, SEE = 0.589 liter/min) if the annular area was derived from the M-mode tracing. Measurement of the anulus in the apical five chamber view yielded a significant underestimation and the area of the aortic bulbus provided an overestimation of cardiac output. Left ventricular inflow was underestimated at the mitral leaflet tips and overestimated at the mitral anulus. The accuracy of pulsed Doppler cardiac output measurements strongly depends on the assumed flow area and sampling site. Both should be determined at the same level in the inflow or outflow tract of the left ventricle. Measurement of cardiac output in the center of the aortic anulus provided the highest accuracy.
在40例患者中，同时采用脉冲多普勒超声心动图和热稀释法测定心输出量（范围为4.0至10.2升/分钟）。取样容积位于二尖瓣环中心、二尖瓣叶尖部以及主动脉环中心。二尖瓣环、主动脉环和主动脉球的圆形横截面积由M型和二维超声心动图直径计算得出。椭圆形二尖瓣开口面积的可变短轴取自M型舒张期瓣叶分离，长轴则源自最大二尖瓣口面积或二尖瓣环直径。心输出量通过将不同面积的时间 - 速度积分与心率相乘来计算。多普勒血流测量与热稀释法显著相关（r = 0.79至0.93）。如果环面积源自M型描记，主动脉环处的血流测量最为准确（r = 0.93，标准误 = 0.589升/分钟）。在心尖五腔视图中测量环会导致显著低估，而主动脉球面积会高估心输出量。二尖瓣叶尖部的左心室流入量被低估，二尖瓣环处则被高估。脉冲多普勒心输出量测量的准确性强烈依赖于假定的血流面积和取样部位。两者都应在左心室流入或流出道的同一水平确定。在主动脉环中心测量心输出量具有最高的准确性。
