Reproducibility of Quantitative Echocardiography: Factors Affecting Variability of Imaging and Doppler Measurements

During the past fifteen years steady advances in echocardiographic technology and extensive clinical research have established imaging and Doppler ultrasound as important techniques in cardiac diagnosis. Echocardiographic measurements of cardiac structure, function, and hemodynamics often provide the best index of the severity of heart disease, and of its progression or response to treatment in individual patients. The accuracy of echocardiography for detection of heart disease and assessment of its severity depends in turn on the reliability of echocardiographic measurements. Optimal use of echocardiography for clinical and research purposes depends on standardization of methods in ways that maximize reproducibility of measurements and facilitate their comparison between laboratories. Although several sources of variability in echocardiographic measurement have been recognized and recommendations made by various investigators to limit variability of individual measurements, the only available review of variability in quantitative echocardiography is restricted to consideration of left ventricular measurements and focuses primarily on M-mode echocardiography.' Accordingly, this review examines in a comprehensive manner the sources of variability of echocardiographic measurements of cardiac chambers, valves, and hemodynamic parameters. The sources of variability in echocardiographic measurement and available approaches to limit such variability and to enhance reproducibility of echocardiographic measurements are examined