Velocity Vector Imaging in Assessing the Regional Systolic Function of Patients with Post Myocardial Infarction

Abstract

To assess the regional systolic function in patients with post myocardial infarction (PMI), using the velocity vector imaging (VVI) technique, a new two-dimensional echocardiographic method. Two-dimensional images of apical four, two chambers and apical long-axis view were obtained in 20 patients with PMI and 15 normal controls. The segmental myocardial systolic peak strain (epsilon), strain rate (SRs), and segmental ejection fraction (SEF) were analyzed with VVI offline software. The result of epsilon in middle segments of the normal control analyzed by VVI was compared with that by tissue Doppler imaging (DTI). The segmental epsilon, SRs, and SEF were significantly lower in infarct segments than in the corresponding segments of the normal controls. There were significant difference in average epsilon, SRs, and SEF among infarct, noninfarct, and normal control segments. The segmental epsilon, SRs, and SEF did not vary significantly from basal to apical segments in the normal control subjects. There was a good correlation on epsilon in middle segments between VVI and DTI (r = 0.710, P < 0.01). The interobserver variability was 4.6% and the intraobserver variability was 7.0%, respectively. The regional systolic function decreased in infarct segments compared with the adjacent noninfarct segments and normal control segments. The systolic function of adjacent noninfarct area was also affected by infarct areas. VVI could recognize and quantify the abnormality of infarct segments and therefore could be a useful tool in assessing the myocardial regional systolic function.