Determination of left ventricular volumes with use of a new nongeometric echocardiographic method: clinical validation and potential application
WA Zoghbi,
JC Buckey,
MA Massey,
and
CG Blomqvist
Department of Medicine, Baylor College of Medicine, Houston, Texas.
A new nongeometric echocardiographic technique for measurement of right and left ventricular volumes was recently validated in vitro. With this method, all images are taken from one point on the chest wall as the transducer is tilted through the ventricle. This approach offers several advantages. No geometric assumptions about ventricular shape are made. All images are acquired from the best echocardiographic window. Furthermore, the digitized points can be used to make a three-dimensional reconstruction of the ventricle. The present study addresses the clinical feasibility of imaging the heart from a single pivoting point in short axis and compares the accuracy of the method in determining left ventricular volumes with that of biplane cineangiography. Twenty-four patients underwent echocardiographic studies within 2 h before angiography. At catheterization, volumes determined by the biplane area-length method ranged between 95 and 368 ml at end-diastole and between 15 and 303 ml at end-systole. A good correlation was observed between ventricular volumes by angiography and echocardiography at end-diastole and end-systole (r = 0.92 and 0.96, respectively). Correlations between volumes by the two techniques were equally good in patients with wall motion abnormalities (n = 13; r = 0.97). Ventricular ejection fraction ranged between 18% and 84% at angiography and correlated well with echocardiographic measurements (r = 0.82). Thus, the echocardiographic tilt method provides accurate determination of left ventricular volume and ejection fraction. This nongeometric method offers the potential for the determination of right ventricular volume and three-dimensional display of the heart.
