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Forward stroke volume calculated from aortic valve echograms in normal subjects and patients with mitral regurgitation secondary to left ventricular dysfunction

1981; Elsevier BV; Volume: 47; Issue: 6 Linguagem: Inglês

10.1016/0002-9149(81)90250-2

1879-1913

Betty C. Corya, Susan Rasmussen, John Phillips, Mary Jo Black,

Cardiac Imaging and Diagnostics

A clinically applicable method was developed for calculating aortic valve stroke volume using the echocardiographically recorded initial and late aortic cusp separation, ejection time and amplitude of posterior aortic root motion during ejection. The formula was tested prospectively in 55 patients for whom 65 Fick [n = 26]or thermodilution [n = 39]cardiac output determinations were performed simultaneously with echocardiography. Aortic valve echograms were recorded in all patients and mitral valve echograms were also recorded in 48 of the 55 patients. Twenty patients had nonrheumatic mitral regurgitation. For the 65 studies, linear correlation (r) was excellent between the aortic valve method and Fick or thermodilution method for stroke volume (r = 0.96, standard error of the estimate [SEE]± 6 cc) and for cardiac output (r = 0.92, SEE ± 0.44 liters). Differences between cardiac output values obtained from aortic valve echograms and either Fick or thermodilution techniques ranged from −1.4 to +1.5 liters/min and were normally distributed. Ninety percent of the computed aortic valve data was within 15 percent of the Fick or thermodilution data. Aortic valve stroke volume correlated well (r = 0.93) with stroke volume derived from mitral valve echograms in the patients without mitral regurgitation but did not correlate well (r = 0.78) in the patients with mitral regurgitation. Mitral valve stroke volume exceeded aortic valve stroke volume by more than 20 percent in 19 of the 20 patients with mitral regurgitation compared with 1 of 28 patients without mitral regurgitation. The presence or absence of ventricular dyssynergy did not alter statistical findings. Data from this study show that (1) aortic valve echograms can be used clinically to measure forward stroke volume, and (2) the difference between mitral valve and aortic valve volume should be a measure of mitral regurgitant flow.