Estimation of right ventricular volume by modified echocardiographic subtraction method.
To evaluate the accuracy and clinical utility of right ventricular volume estimated by a modified echocardiographic subtraction method versus Krebs' original subtraction method, an experiment was performed on hearts excised from 25 animals (dogs, pigs, and cows) followed by a clinical study of 41 patients with heart disease. Right ventricular volume was measured by subtracting the left ventricular volume from that of the whole heart based on echocardiographic apical two- and four-chamber views by means of the area-length method. In the animal heart study, the coefficient of variation between the right ventricular volume estimated by the modified method and the true volume was +/- 13%. The regression equation was y = 0.94x + 4.15 (r = 0.987, p less than 0.001) and showed good correlation, whereas the right ventricular volume obtained by the original method underestimated the true volume (coefficient of variation = +/- 25%, y = 0.59x + 1.11; r = 0.976, p less than 0.001). In the clinical study, the coefficient of variation between right ventricular volume estimated by the modified echocardiographic method and RV volume estimated by radionuclide ventriculography was +/- 15%. The regression equation was y = 0.80x + 13.3 (r = 0.935, p less than 0.001). This correlation was better than that obtained by the original method (coefficient of variation = +/- 16%), where the regression equation was y = 0.60x + 2.43 (r = 0.888, p less than 0.001). Thus the accuracy of the modified subtraction method was validated, and this method showed a better correlation than the original method both experimentally and clinically.
Tomita
M
M
Second Department of Internal Medicine, Gifu University School of Medicine, Japan.
Masuda
H
H
Sumi
T
T
Shiraki
H
H
Gotoh
K
K
Yagi
Y
Y
Tsukamoto
T
T
Terashima
Y
Y
Miwa
Y
Y
Hirakawa
S
S
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D002417:Cattle; D004285:Dogs; D004452:Echocardiography / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D006331:Heart Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000503:physiopathology; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D015635:Radionuclide Ventriculography; D012044:Regression Analysis; D015203:Reproducibility of Results; D013382:Subtraction Technique; D013552:Swine; D013815:Thermodilution; D016278:Ventricular Function, Right / Q000502:physiology*