Cineangiographic evaluation of changes in regional left ventricular wall motion after acute myocardial infarction.

To evaluate the natural course of changes in regional left ventricular function after acute myocardial infarction, we compared cineventriculograms taken during the acute and chronic stages of myocardial infarction in ten patients who had sustained coronary occlusion despite intracoronary thrombolysis. Three ventricular silhouettes (end diastole, aortic valve opening, and closure) were superimposed using external reference markers, and 36 radial grids were drawn from the center of gravity of the end-diastolic silhouette to the endocardial margin of each silhouette. Measurement of the length of each radial grid provided quantitative details of segmental centripetal wall motion. In the infarcted area, percentage total systolic shortening (% delta LTOT), iso-volumic shortening (% delta LISO), and ejection phase shortening (% delta LEJ) remained unchanged. In the nonischemic area, % delta LTOT tended to increase from 34% +/- 6% to 41% +/- 6%. Although % delta LISO was unchanged (9% +/- 4% vs. 8% +/- 1%), % delta LEJ increased from 25% +/- 4% to 37% +/- 6% (P less than 0.05). Thus, progressive increases in ejection phase shortening in normal regions may contribute to the functional recovery of the left ventricle after myocardial infarction.