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
Objective To investigate ventricular remodeling and glucose transporter 4(GLUT4) expression in rat with type 2 diabetes mellitus(DM) complicated with myocardial infarction (MI), as well as the effects of ramipril on ventricular remodeling and CLUT4 expression. Method Diabetic animal model (DM) was produced by cholesterol-diet and intraperitoneal injedtion of streptozotocin (STZ,30 mg/kg). The successful model was identified based on the blood gulcose value > 6.7 mmol/L. Left anterior descending coronary artery was ligated to produce the model of MI. 46 wistar rats were randomly(random number) divided into 5 groups: DM + MI + placebo group(placebo group, n = 9), DM + MI + ramipril group(ramipril group, n = 10), DM + sham-operation group (DM group, n = 10),non-DM group + MI (MI group, n = 9), and non-DM + sham-operation group (n = 8). After six weeks, echocardiographic studies was performed ; Left ventricular mass index (LVMI), myocardial infarct size and myocardial collagen volume fraction(CVF) of non-infarction area were also detected. GLUT4 mRNA in the myocardium away from infarction region was measured with real-time fluorescent quantitative RT-PCR and the expression of GLUT4 protein was measured with western blot. Analysis of variance was used to compare the groups. P -values< 0.05 were considered to indicate statistically significant differences. Results Compared with Ml group and DM group,EF[(32 ±3)% vs. (65 ±4)%, P <0.01 and (32 ±3)% vs. (38 ±4)%, P <0.05 respectively] significantly decreased,while E/A ratio (P < 0.01), LVMI (P < 0.05) and CVF (P < 0.05) obviously increased in placebo group. The expression of GLUT4 mRNA and protein were similar between placebo group and DM group, however, much lower than those in MI group(P<0.01).In rampiril group, E/A ratio (P < 0.01), LVMI(3.1±0.2 vs.4.2±0.4, P <0.01) and CVF(P < 0.05) significantly decreased compared with placebo group, while EF[(45±3)% vs.(32±3)%, P <0.01] and the expression of GLUT4 mRNA and protein (P < 0.05) increased. Conclusions Rampiril could improve left ventricular hypertrophy and systolic/di-astolic dysfunction, increase the expression of GLUT4 mRNA and protein in diabetic rats complicated with MI.
ABSTRACT
Objective To explore the feasibility of right ventricular outflow tract index in the evaluation on right ventricular systolic function and its relationship to other right ventricular functional indices generally accepted in clinical practice. Methods Sixty-one patients with heart failure were randomly selected and divided into elevated right side pressure group and normal right side pressure group by pressure gradient ≥35 mm Hg aquired from tricuspid regurgitation velocity. Twenty-four healthy adults were selected as control group. All the people experienced transthoracic echocardiography. Right ventricular longitudinal excursion(RVLX), right ventricular ejection fraction(RVEF), right ventricular outflow-tract fractional shortening(RVOTFS) and right ventricular ejection time(RVET) were measured, and their differences were compared between healthy adults and heart failure patients as well as between elevated right side pressure group and normal right side pressure group. Relationships of RVOTFS with other right ventricular functional indices were also analyzed. Results Compared with healthy adults, heart failure patients had lower RVOTFS((0.49)?(0.13) vs (0.22)?(0.09),P