Echoventriculography in acute myocardial infarction. IV. Infarct size and reliability by pathologic anatomic...

A morphologic-echocardiographic comparison was carried out in 24 consecutive patients to determine the accuracy of multidirectional single-beam echocardiography in imaging the size and site of 22 fatal acute myocardial infarctions and of 2 postinfarction ventricular aneurysms treated surgically. Echocardiography never missed the infarction, regardless of whether the infarction was anterior or posterior. The correlation between the echocardiographic and pathologic anatomic extent of infarct, as expressed by a percentage of the left ventricular horizontal circumference, was r=0.88 (p less than 0.001). One hundred four of one hundred eleven infarcted segments (94%) were detected by echo; only the posterior septal and the most lateral segments of the left ventricle tended to remain out of range of the method. The regional asynergy at the center of the infarcted region was clearcut-systolic thickening was never seen and the systolic wall motion was paradoxical in 75% of the patients (mean, -20+/-2.0 mm). Analysis of the regional function from multiple sites characterized reduction of the left ventricular performance (p less than 0.0005) better than did the ejection fraction in the presence of asynergy. An old postinfarction scar was differentiated from the acute necrosis. Thus, segmental left ventricular akinesis or paradoxical motion as seen by multidirectional echocardiography permits noninvasively a reliable estimation of the extent of acute myocardial infarction.