斑点追踪技术对急性心肌梗死患者再灌注治疗前后内、外膜心肌扭转的研究

目的 应用斑点追踪技术通过心内膜旋转角度、心外膜旋转角度及跨壁角度梯度三者峰值指标对急性心肌梗死(心梗)患者再灌注治疗前、后室壁运动异常及心功能进行评价.方法 正常对照组20例,急性前壁心梗患者21例,对正常组、心梗术前及术后1月分别行常规超声检查后,获取左室心尖及心底短轴切面二维图像各3个心动周期,使用QLab软件进行脱机分析,得到两短轴切面心内、外膜旋转角度及跨壁角度梯度.结果 无论在心尖还是在心底短轴切面,与正常组相比,术前组内膜旋转角度峰值、外膜旋转角度峰值及跨壁角度梯度峰值均降低(P<0.01).再灌注治疗1月,术后组上述三个指标均较术前组有不同程度改善,差异有统计学意义(P<0.05),且内膜改善优于外膜.同时,左室射血分数(r=0.717,P<0.01)、舒张末容积(r=-0.694,P<0.05)与心尖内膜旋转角度峰值相关良好,而与心底及心尖其他各指标无明显相关性.结论 心内、外膜旋转角度及跨壁角度梯度峰值是评价急性心梗患者再灌注治疗前、后室壁运动异常及心功能的敏感指标之一.

Assessment of endocardial and epicardial rotation of left ventricle in patients with acute myocardial infarction before and after revascularization by speckle tracking imaging

Objective To evaluate peak rotation in the endocardium(endo)and epicardium(epi)and peak mural torsion in patients with anterior wall acute myocardial infarction(AMI)before and after revascularization by speckle tracking imaging(STI).Methods The study comprised 20 normal controls and 21 consecutive xpatients with a first-episode anterior wall AMI with stenosis of the left anterior descending artery.All patients underwent Successful percutaneous coronary intervention within 12h onset of AMI.During one month, two patients were ruled OUt because one died of heart failure and the other suffered from persistent atrial fibrillation.Conventional echocardiography and STI were performed in normal controls and AMI patients before and one month after revascularization.Results In the left ventricle(LV)apical and basal level,peak endo-and epi-rotation and peak mural torsion in AMI patients were significantly reduced relative to those of normal control group(all P<0.01).One month after revascularization,there were significant changes in these three variables,especially in peak endorotation(P<0.01).Peak apical endo-rotation positively correlated with LV ejection fraction(LVEF)(r=0.717,P<0.01)and inversely correlated with LV end-diastolic volume(EDV)(r=-0.694,P<0.05).However,tight relations were not found among other variables at the two planes.Conclusions Peak endo-and epi-rotation and peak mural torsion can make the sensitive assessment of abnormal myocardial contractile performancein AMI patients using STI.