Evaluation of the left ventricular remodeling in patients with myocardial infarction after revascularization with intravenous real-time myocardial contrast echocardiography

Abstract

In order to evaluate the left ventricular remodeling in patients with myocardial infarction after revascularization with intravenous real-time myocardial contrast echocardiography (RT-MCE), intravenous RT-MCE was performed on 20 patients with myocardial infarction before coronary revascularization. Follow-up echocardiography was performed 3 months after coronary revascularization. Segmental wall motion was assessed using 18-segment LV model and classified as normal, hypokinesis, akinesis and dyskinesis. Myocardial perfusion was assessed by visual interpretation and divided into 3 conditions: homogeneous opacification=1; partial or reduced opaciflcation or subendocardial contrast defect=2; constrast defect=3. Myocardial perfusion score index (MPSI) was calculated by dividing the total sum of contrast score by the total number of segments with abnormal wall motion. Twenty patients were classified into 2 groups according to the MPSI: MPSI≤1.5 as good myocardial perfusion, MPSI>1.5 as poor myocardial perfusion. To assess the left ventricular remodeling, the following comparisons were carried out: (1) Comparisons of left ventricular ejection fraction (LVEF), left ventricular end-systolic volume (LVESV) and left ventricular end-diastolic volume (LVEDV) before and 3 months after revascularization in two groups; (2) Comparisons of LVEF, LVESV and LVEDV pre-revascularization between two groups and comparisons of these 3 months post-revascularization between two groups; (3) Comparisons of the differences in LVEF, LVESV and LVEDV between 3 months post-and pre-revascularization (ΔLVEF, ΔLVESV and ΔLVEDV) between two groups; (4) The linear regression analysis between ΔLVEF, ΔLVESV, ΔLVEDV and MPSI. The results showed that the LVEF obtained 3 months after revascularization in patients with MPSI>1.5 was obviously lower than that in those with MPSI≤1.5. The LVEDV obtained 3 months post-revascularization in patients with MPSI>1.5 was obviously larger than that in those with MPSI≤1.5 (P=0.002 and 0.04). The differences in ΔLVEF and ΔLVEDV between patients with MPSI>1.5 and those with MPSI≤1.5 were significant (P=0.002 and 0.001, respectively). Linear regression analysis revealed that MPSI had a negative correlation with ΔLVEF and a positive correlation with ΔLVESV, ΔLVEDV (P=0.004, 0.008, and 0.016, respectively). It was concluded that RT-MCE could accurately evaluate the left ventricular remodeling in patients with myocardial infarction after revascularization.

Keywords

real-time myocardial contrast echocardiography / myocardial infarction / left ventricular remodeling / revascularization

References

[1] BologneseL., NeskovicA. N., ParodiG., et al.. Left ventricular remodeling after primary coronary angioplasty patterns of left ventricular dilation and long-term prognostic implications. Circulation, 2002, 106: 2351-2357

[2] SuttonM. G., SharpeN.. Left ventricular remodeling after myocardial infarction: pathophysiology and therapy. Circulation, 2000, 101(25): 2981-2988

[3] RouleauJ. L., de ChamplainJ., KleinM., et al.. Activation of neurohumoral systems in postinfarction left ventricular dysfunction. J Am Coll Cardiol, 1993, 22: 390-398

[4] PfefferM. A., BraunwaldE., MoyeL. A., et al.. Effect of captopril on mortality and morbidity in patients with left ventricular dysfunction after myocardial infarction: results of the survival and ventricular enlargement trial; the SAVE investigators. N Engl J Med, 1992, 327: 669

[5] GaudronP., EillesC., KuglerI., et al.. Progressive left ventricular dysfunction and remodeling after myocardial infarction: potential mechanisms and early predictor. Circulation, 1993, 87: 755-763

[6] WhiteH. D., NorrisR. M., BrownM. A., et al.. Left ventricular end-systolic volume as the major determinant of survival after recovery from myocardial infarction. Circulation, 1987, 76: 44-51

[7] DionisopoulosP., SmartS. C., SagarK. B., et al.. Dobutamine stress echocardiography predicts left ventricular remodeling after acute myocardial infarction. J Am Soc Echocardiogr, 1999, 12: 777-784

[8] AbeY., MuroT., SakanoueY., et al.. Intravenous myocardial contrast echocardiography predicts regional and global left ventricular remodeling after acute myocardial infarction: comparison with low dose dubutamine stress echocardiography. Heart, 2005, 91: 1578-1583

[9] JeetleyP., SwinburnJ., HickmanM., et al.. Myocardial contrast echocardiography predicts left ventricular remodeling after acute myocardial infarction. J Am Soc Echocardiogr, 2004, 17: 1030-1036

[10] LiP., DengY. b., YangH. Y., et al.. Assessment of myocardial perfusion by intravenous real-time myocardial contrast echocardiography before and after bypass surgery in patients with coronary artery disease. Chin J Ultrasonogr (Chinese), 2007, 16: 19-22

[11] MyersJ. H., StirlingM. C., ChoyM., et al.. Direct measurement of inner and outer wall thickening dynacute myocardial infarctions with epicardial echocardiography. Circulation, 1986, 74: 164-172

[12] TouchstoneD. A., BellerG. A., NygaardT. W., et al.. Effects of successful intravenous reperfusion therapy on regional myocardial function and geometry in humans: a tomographic assessment using two-dimensional echocardiography. J Am Coll Cardiol, 1989, 13: 1506-1513

[13] ItoH., MaruyamaA., IwakuraK., et al.. Clinical implications of the “no reflow” phenomenon: a predictor of complications and left ventricular remodeling in reperfused anterior wall myocardial infarction. Circulation, 1996, 93: 223-228