[Echocardiographic assessment for surgical treatment in patients with aortic stenosis]

The diagnostic value of preoperative echocardiography was assessed in 51 patients with aortic stenosis. We measured 1) left ventricular-aortic pressure gradient (LV-Ao PG), 2) aortic valve area (AVA), 3) grade of LV hypertrophy and function, and 4) aortic annulus diameter for determining the availability and size of a prosthesis. The maximal instantaneous PG (max-PG) by continuous-wave (cw) Doppler echocardiography correlated well with the peak-to-peak PG by cardiac catheterization (cath), and their correlation equation was y = 1.49 x -48.3 with a correlation coefficient of 0.90. Excellent correlations were also found between cw-max PG and cath-max PG (r = 0.84), and between cw-mean systolic PG and cath-mean systolic PG (r = 0.80). The AVA of the echocardiogram, which was derived from the stroke volume using Gibson's M-mode echocardiographic formula and the cw-Doppler echocardiographic mean gradient, correlated well with the AVA of the cardiac catheterization using Gorlin's formula (y = 1.33 x -0.61, r = 0.79). Preoperative LV pump function, which was obtained from the M-mode echocardiogram, correlated inversely with end-systolic wall stress, and a depressed LV pump function was observed in patients with inadequate hypertrophy. In such patients, however, depressed function was alleviated after surgical treatment. Thus, we considered that cardiac catheterization for further examination is unnecessary, even in such patients. To determine the available size of the prosthesis, measurement of the inner diameter of the aortic annulus on the long-axis cross-sections was the most useful.(ABSTRACT TRUNCATED AT 250 WORDS)