Videometry studies of left ventricular wall movement after myocardial infarction.

Investigations using videometry were made on 15 normal subjects and 20 patients with previous myocardial infarction; videometry is a new radiological method of measuring the amplitude and rate of displacement of the left ventricular wall. Videotape recordings of the movement of the left heart border as seen on a conventional image intensifier television screening set are made simultaneously with a record of the electrocardiogram. The videometer is used to analyse the movements of the image of the left ventricle at 5 positions along its length in the posteroanterior, left anterior oblique, and lateral projections. Abnormalities of movement amounting to dyskinesia or paradox were commonly found, in addition to an overall reduction in amplitude and rate of systolic displacement in the abnormal group. Unexpectedly, two of the normal subjects also showed dyskinetic activity at the apex and a hypothesis is proposed to explain the phenomenon.