ABSTRACT
Temporal and spatial disturbances of left ventricular function were studied in the cineangiogram in 34 patients with isolated disease of the left anterior descending (LAD) coronary artery and compared with 12 normal subjects. Classical anterior wall infarction caused impaired contraction of the distal two thirds of the anterior wall, the apex, and the distal quarter of the inferior wall, with marked delay in contraction and relaxation of the border zones and hyperkinesis of the inferior wall. Left bundle branch block induced profound temporal delay particularly during relaxation.
Different methods of assessing spatial and temporal contraction defects were measured and compared. The dysfunction index, calculated as the area that the shortening fraction curve of the patient derived from 100 equiangular radii, fell below 1 SD of the normal population, was simple to measure, and gave good discrimination between different syndromes of left ventricular dysfunction.
When classical thrombolysis with intravenous streptokinase was used to achieve reperfusion (65 patients with a first anterior myocardial infarction and a patent infarct related coronary artery), the dysfunction index was an excellent method of assessing myocardial damage. The dysfunction index showed that infarct size was related to the time delay until streptokinase was administered (less than 2 h), the delay until reperfusion was achieved (an additional 1 1/2 h), and residual stenosis of more than 75% in the infarct-related coronary artery. Simple computer interactive methods can be used to assess regional ventricular dysfunction and infarct size.
