Digital computer analysis of M-scan echocardiograms

In the past few years, echocardiography has emerged as a useful noninvasive clinical tool in cardiac diagnosis. Conventional methods for analyzing echocardiographic data involve time consuming and tedious manual techniques for measuring various distances and computing cardiac parameters of interest. This paper describes a useful method for automating the analysis of M scan echocardiograms both for routine clinical work as well as for special research oriented ultrasonic cardiac studies. Using a GRAF/PEN digitizer interfaced to a PDP-11 minicomputer system, relevant points of the ventricular and mitral valve interfaces, R-R intervals, and time and distance calibration points are entered from hard copies of M scan echocardiograms. The computer then determines all the parameters of interest such as left ventricular (LV) diameters, LV volumes, LV mass, ejection fraction, stroke volume, cardiac output, septal and posterior wall dynamics, as well as such mitral valve (MV) parameters as opening/closing velocities, excursions, and areas subtended by both MV leaflets. The data and results are stored on disc or tape and a report of the results is immediately available from a printer for incorporation into the patient's record file.