定量组织速度成像对心梗病人左室心肌局域舒张功能的分析

目的探索冠心病人左室等容舒张期和快速充盈期局部心肌的舒张运动特点及其临床意义。方法以60帧/秒以上的高帧频对18例心肌梗死病人（MI组）和20例正常人（对照组）的左室心肌进行QTVI检查。获取左室各节段心肌长轴方向的同步运动曲线，测量其等容舒张期、快速充盈期、心房收缩期局部心肌的运动速度V

Evaluation of Regional Diastolic Function in Patients with Myocardial Infarction Using Quantitative Tissue Velocity Imaging

Objection This study was undertaken to detect the regionaldiastolic wall motion features during isovolumic relaxation and early diastole in patients with coronary artery disease,and their clinical significance.Methods 18 patients with myocardial infarction(MI) and 20 normal subjects(Nor) underwent quantitative tissue velocity imaging (QTVI) with frame rates of over 60 per second.Off-line left ventricular regional velocity profiles along long axis were obtained synchronously,and peak tissue velocities of LV segments during isovolumic relaxation (VIR ),early diastole (VE) and atrial contraction (VA) were measured.Mitral valve peak flow velocities during early diastole (E) and atrial contraction (A) were also measured and A/E ratio was calculated.Results VIR ＜2.0cm/s in 17 of 20 normal subjects (85％),344 of 360 (95.6％) myocardial segments,and the average value is -0.26±1.13cm/s;VIR ＞2.0cm/s only in 3 of 20 subjects (15％),16 of 360 (4.4％) segments.Whereas VIR ＞2cm/s in 16 of 18 (88.9％) MI patients,77 of 324 (23.8％) segments; VIR ＜2cm/s in 2 of 18 (11.1％) patients,247 of 342 (76.2％) segments,with average of 0.04±1.46cm/s.The differences of VIR ＞2.0cm/s numbers (P＜0.001) and VIR values (P＜0.005) between the two groups are significant.Regional minor VIR combining neighbor segments VIR ＞2.0cm/s are helpful in diagnosing regional diastolic wall motion abnormalities,with sensitivity,specificity,accuracy rate and positive predictive value of 88.9％,85％,86.8％ and 84.2％,respectively.A/E＞1 appears in more MI patients (11 of 18,61.1％) than normal subjects (7 of 20,35％; P＜0.05),but VIR and A/E have no correlation.The sensitivity and specificity of A/E＞1 in LV diastolic abnormality assessment are 61.1％ and 63.2,respectively.Conclusion Regional myocardial ischeamia and infarction can course significant regional diastolic wall motion abnormalities along long axis,and QTVI can evaluate the abnormalities quantitatively and synchronously with high sensitivity,and have the potential value in regional myocardial ischeamia diagnosis.