ASSESSMENT OF MYOCARDIAL VELOCITY GRADIENT IN ISCHEMIC HEART DISEASE PRE AND POST PTCA

The aim of this study was to determine whether myocardial velocity gradient (MVG) derived from color Doppler myocardial imaging could detect regional changes in the left ventricular function following successful percutaneous coronary angioplasty (PTCA) and to relate these changes to the territory at risk according to the target vessel. We studied 19 patients (pts) undergoing single vessel PTCA. 11 pts underwent PTCA of the LAD and 8 pts of the LCx. Color coded tissue Doppler images were obtained from the parasternal mid short axis view and endocardial and epicardial velocities were measured in the anterior wall, septal wall and lateral wall. Each MVG was calculated by the subtraction of epicardial velocity from endocardial velocity. Peak MVG pre and post PTCA was measured in systole during ventricular ejection (SE) and diastole during isovolumic relaxation (IVR), rapid ventricular filling (RVF) and atrial contraction (AC). In pts undergoing PTCA of the LAD there was a significant increase in the anterior wall in SE (2.4 +/- 1.1 vs 4.3 +/- 1.2, p = 0.03), IVR (0.6 +/- 0.3 vs – 0.2 +/- 0.1, p = 0.05) and RVF (2.6 +/- 0.9 vs 4.4 +/- 1.6, p = 0.04) and in the septal wall in SE (2.2 +/- 1.3 vs 3.9 +/- 1.3, p = 0.05), IVR ( 0.4 +/- 0.1 vs –0.3 +/- 0.1, p = 0.01) and RVF (2.7 +/- 0.3 vs 3.8 +/- 0.9, p = 0.05). In the pts undergoing PTCA of the LCx there was an improvement in the anterior wall in SE (2.6 +/- 0.9 vs 4.1 +/- 1.1, p = 0.05), IVR (0.5 +/- 0.2 vs – 0.2 +/- 0.1, p = 0.03) and RVF (2.2 +/- 0.4 vs 4.1 +/- 1.1, p = 0.03) and in the lateral wall in SE (2.8 +/- 0.9 vs 4.5 +/- 1.4, p = 0.04), IVR (0.6 +/- 0.1 vs – 0.3 +/- 0.1, p = 0.02) and RVF (2.6 +/- 0.2 vs 4.2 +/- 1.3, p = 0.04). Thus, MVG allows the detection of early improvement in regional left ventricular function after the release of ischemia by successful PTCA.