Martin R W, Graham M M, Kao R, Bashein G
Department of Anesthesiology, University of Washington, Seattle 98195.
J Cardiothorac Anesth. 1989 Jun;3(3):260-8. doi: 10.1016/0888-6296(89)90105-1.
A transesophageal, ultrasonic cardiac imaging probe was built that incorporated a mechanism for changing the angle of the imaging plane of a conventional phased array in a precise and known manner. This probe was used to acquire an angular spatial sequence of two-dimensional images of the left ventricular cavity over a series of cardiac cycles by sweeping the imaging plane through it stepwise. The endocardial borders of these images were manually outlined off-line and the application of a three-dimensional reconstruction algorithm was then used to compute the left ventricular end-diastolic and end-systolic volumes and ejection fraction. A study was conducted with seven anesthesized dogs to compare ultrasonic determinations by this method with determinations and measurements made using radionuclide and thermal dilution methods. Comparison of 33 ejection fractions, measured by the ultrasonic volume method and by the gated blood pool radionuclide approach, yielded a correlation coefficient of 0.87 and a standard error of the estimate of 5.7% measured over a range of 10% to 58% (average, 40%). Comparison of the ultrasonically measured volumes with those calculated from stroke volume (derived from thermal dilution cardiac output measurement) and ejection fraction (measured by radionuclide technique) produced a correlation coefficient of 0.92 and a standard error of the estimate of 10.3 mL over a range of 18 to 130 mL (average, 56 mL). The accuracy of volume and ejection fraction measurements with this new ultrasonic method seems comparable to that of other currently used clinical approaches such as radionuclide and angiography.
构建了一种经食管超声心动成像探头，该探头包含一种机制，能够以精确且已知的方式改变传统相控阵成像平面的角度。通过逐步扫过成像平面，使用该探头在一系列心动周期内获取左心室腔二维图像的角度空间序列。离线手动勾勒出这些图像的心内膜边界，然后应用三维重建算法计算左心室舒张末期和收缩末期容积以及射血分数。对7只麻醉犬进行了一项研究，以比较该方法的超声测定结果与使用放射性核素和热稀释法进行的测定及测量结果。通过超声容积法和门控血池放射性核素法测量的33个射血分数进行比较，在10%至58%（平均40%）的范围内，相关系数为0.87，估计标准误差为5.7%。将超声测量的容积与根据每搏量（由热稀释心输出量测量得出）和射血分数（通过放射性核素技术测量）计算得出的容积进行比较，在18至130 mL（平均56 mL）的范围内，相关系数为0.92，估计标准误差为10.3 mL。这种新的超声方法测量容积和射血分数的准确性似乎与目前使用的其他临床方法（如放射性核素和血管造影）相当。
