Evaluation of Left Ventricular Function by Echocardiography

TLDR

Echocardiography was used to measure ventricular minor‑axis dimensions at end‑systole and end‑diastole in five patient groups, from which left‑ventricular volumes, ejection fraction, velocity of circumferential fiber shortening, and shortening duration were calculated. The echocardiographic measurements closely matched angiographic data and allowed differentiation of heart‑failure patients from normals, with reduced parameters in mitral stenosis, normal values in volume overload, increased values in hypertrophic subaortic stenosis, and overall feasibility of noninvasive ventricular function assessment in many ambulatory patients.

Abstract

Ventricular minor-axis dimensions were measured by echocardiography at end-systole (S 8 ) and end-diastole (S D ) in five groups of patients: (I) normal; (II) mitral stenosis; (III) compensated volume overload; (IV) idiopathic hypertrophic subaortic stenosis; and (V) congestive heart failure. Cardiac pump function was evaluated by determination of left ventricular volumes and ejection fraction (EF) from the echographic dimensions using formulae previously reported. The mean velocity of circumferential fiber shortening (V CF ), a parameter of cardiac muscle performance previously obtained only by invasive methods, was determined from the echographic dimensions by the formula:[See Equation in PDF File]. The duration of minor-axis shortening (dt) was measured directly from the echocardiogram. Dimension and volume measurements in these groups of patients were similar to those reported in similar patients determined by angiographic methods. Measurement of the relative changes in echographic dimensions with systole (%ΔS), EF, and V CF allowed separation of patients with clinical heart failure (group V) from normal subjects (group I). Patients in group II had reduced values for these parameters compared to group I. Those in III did not differ significantly, and those in IV had increased values. In general, V CF , EF, and %ΔS showed similar trends, but individual patients sometimes differed. The findings reported here demonstrate the feasibility of evaluating ventricular function by a noninvasive method in a large group of ambulatory patients.