The validity of using the measurement of the cardiac silhouette as an objective guide for the evaluation of left ventricular performance was investigated in 75 patients with arteriographically demonstrated coronary heart disease. None of the measurements of the silhouette, when normal, reliably excluded poor left ventricular function. Even the most reliable dimensions of the cardiac silhouette, the frontal plane transverse diameter, oblique diameter, and cardiothoracic ratio, frequently were normal in individuals with moderate to severe impairment of ventricular function. The results of this study suggest that the size of the cardiac silhouette should be considered only secondarily for the purpose of clinically evaluating the functional state of the left ventricle. By implication, these results also suggest that a greater reliance should be placed on other clinical methods, including a carefully taken history and physical examination.
(JAMA 229:1614-1620, 1974)
Stein PD, Lewinson H, Potts KH. Cardiac Size and Left Ventricular PerformanceLack of Correlation With Silhouette Measurement. JAMA. 1974;229(12):1614–1620. doi:10.1001/jama.1974.03230500032022