不同部位心肌梗死对左心室收缩期涡流影响的初步研究

The impact of different infarction sites on left ventricular systolic vortex-a pilot study

目的应用血流向量图（vectorflowmap，VFM）技术对不同部位心肌梗死患者收缩期涡流特点进行连续动态观察，比较前壁和下后壁节段性运动异常对收缩期涡流的影响。方法根据冠状动脉造影结果将冠心病心肌梗死患者分为单纯左前降支病变组（LAD组）和左旋支或（和）右冠病变组（LCX／RCA组）。应用VFM技术观察两组收缩期心腔内血液流场特点，计算涡流持续时间等参数并与正常对照组相比较。结果LAD组等容收缩期整体涡流同正常组无明显差异，射血早期涡流范围大，常在心尖部形成局部涡流；LCX／RCA组等容收缩期涡流范围较小，射血早期涡流较LAD组明显减小，较正常组增大，出现的部位多位于心腔中部。病例组涡流总持续时间和瓦解时间均较对照组延长，LAD组和LCX／RCA组比较差异无统计学意义；整体涡流持续时间三组间差异无统计学意义。结论前壁心肌梗死对收缩期左室血液流场的影响较下后壁更明显，VFM技术可以用于显示并评价该变化。

Objective To compare the impact of anterior and inferior-posterior regional wall motion abnormalities on the vortex in systolic phase by vector flow map（VFM） technique. Methods Sixty patients with myocardial infarction were divided into 2 groups：the left anterior descending artery single branch lesion group （LAD group） and the left circumflex artery and/or right coronary artery lesion group （LCX/RCA group）. By VFM technique,left ventricular systolic blood flow field was observed. Parameters such as the vortex duration were calculated and compared between two patient groups and also with healthy control group. Results LAD group did not show significant difference from the control group in isovolumic systolic vortex,this group was characterized with large size of vortex and usually forming local vortex at the apex in early ejection. On the contrary, LCX/RCA group had small isovolumic systolic vortex, the early ejection vortex of this group was significantly smaller than that of LAD group and larger than that of control group. The phenomenon was usually observed in the center of the lumen. Both LAD and LCX/RCA group had longer total vortex duration and vortex collapse time than the healthy control group, these differences were not significant between LAD and LCX/RCA group. There were no significant differences in isovolumic vortex duration among the three groups. Conclusions Anterior wall infarction had more impact on systolic blood flow field than inferior-posterior wall infarction. The VFM technique could be applied for observation and evaluation of the changes in vortex characteristics.