ABSTRACT
Objective Analysis of myocardial microvascular perfusion in patients with chronic total coronary occlusion (CTO) who underwent a coronary artery bypass graft (CABG) use real-time myocardial contrast echocardiography (RTMCE),to provide an effective method of detecting viable myocardium and a reference for the choice of CABG indications.Methods Twenty-seven patients with CTO underwent RTMCE 1 week before CABG,they underwent follow-up echocardiography and coronary artery 256-slice multislice computed tomography aagiography 1 year after CABG.Myocardial viability was defined as a postoperative ultrasound wall motion significantly improved ≥ 1 point.Semi-quantitative analysis of contrast images,myocardial viability was defined as myocardial perfusion score ≤ 2 points.Viable myocardium by quantitative assessment of myocardial blood flow (MBF) was determined by analyses of receiver-operating characteristic (ROC) curves.Results Patients with LVEF increased significantly after CABG (P ＜ 0.01),Of 259 segments with wall motion abnormality,149 (58％) showed wall motion significantly improved ≥ 1 point after CABG,considered viable myocardium,110 (42％) were not observed in wall motion improved,considered to be non-viable.The viable myocardial segments were significantly greater than non-viable myocardial segments in A,β,A × β value (P ＜ 0.01).Compared with the semi-quantitative analysis,quantitative analysis of MBF increased the sensitivity and accuracy of RTMCE for detecting viable myocardium (P ＜ 0.05).Conclusion RTMCE could accurately assess myocardial viability and provide a strong reference for clinical decision making and judging prognosis.
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 (△LVEF, △LVESV and △LVEDV) between two groups; (4) The linear regression analysis between △LVEF, △LVESV, △LVEDV 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 △LVEF 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.