Use of computer analysis of echocardiograms for assessment of left ventricular function.

Computer analysis of M-mode echocardiograms has been used for evaluation of left ventricular function. Ventricular dimensions and velocities of heart wall movement have been measured. In addition, a non-invasive estimate of ventricular wall stress has been obtained using the systolic cuff blood pressure combined with echocardiogram data, and simultaneous apex cardiography has been employed to look for any disruption in the timing of changes in ventricular dimension and wall stress. Various parameters have been calculated from the data to provide a quantitative indication of changes in the ventricle. A study has been carried out of 117 patients divided into four groups; one of normal subjects and the others containing patients with ischaemic heart disease, hypertrophic cardiomyopathy and dilated cardiomyopathy. Abnormal features of the echocardiograms have been evaluated from comparisons with data for normal subjects. Relationships between the quantities measured have been studied to give a fuller understanding of changes taking place in the ventricle, so that the data can be employed as the basis for a non-invasive assessment of ventricular function.