超声应变率成像技术在冠状动脉支架置入前后左室舒张功能评价中的应用价值

Application value of strain rate imaging on sonography in evaluation of ventriculus sinister diastolic function before and after placement of stents in coronary artery

目的探讨冠状动脉支架置入术前后应用应变率成像技术(SRI)评价左室舒张功能的临床价值。方法 40例冠心病患者分别于支架置入术前和术后7 d行超声心动图检查,获取左室射血分数(EF),二尖瓣口舒张早期峰值流速(VE)和舒张晚期峰值流速(VA)及E峰下降时间(DT);采用应变率成像获取左室狭窄冠脉供血节段和非狭窄节段的收缩期峰值应变率(SRS)、舒张早期峰值应变率(SRE)等。结果支架置入术后7 d,左室EF、VE明显增加,VE/VA升高、DT降低,与支架置入术前比较,差异有统计学意义(P<0.05)。支架置入术前及术后7 d,狭窄节段及非狭窄节段的SRS比较,差异均无统计学意义(P>0.05)。支架置入术前,狭窄节段SRE显著低于非狭窄节段,二者比较差异有统计学意义(P<0.05);术后7 d,狭窄节段SRE较术前显著增加(P<0.05),而非狭窄节段SRE术前与术后无明显变化(P>0.05),术后7 d二者SRE水平相似(P>0.05)。狭窄节段ΔSRE%与二尖瓣口ΔVE之间存在正相关性(r=0.58,P<0.05);非狭窄节段ΔSRE%与ΔVE之间无明显相关性(r=0.16,P>0.05)。结论冠状动脉支架置入术前后应用应变率成像技术可以准确反映左室心肌运动变化和局部心肌功能改善状况,准确评价支架置入术的临床疗效。

Objective To investigate the application value of strain rate imaging on sonography in evaluation of ventriculus sinister diastolic function before and after placement of stents in coronary artery. Methods Forty patients with coronary heart disease received echocardiography before and 7ds after placement of stents. Ventriculus sinister ejection fraction （EF）, peak velocity in early relaxation period （V E）, advanced relaxation period （VA） at mitral orifice, and descending time （DT） of E peak were obtained. Strain rate imaging was used to obtain peak strain rate in systole period （SRs） and early relaxation period （SRE） and in the blood-supply segments in stenotic coronary arteries and non-stenotic segments in ventriculus sinister. Results Seven days after placement of stents, ventriculus sinister EF and VE significantly increased, VF/VA increased and DT decreased. Compared with those before placement of stents, the differences were statistically significant （P〈0.05）. The differences in SRs in the stenotic and non-stenotic segments before and 7ds after placement of stents were statistically insignificant （P 〉0.05）. Before placement of stents, the SRE in stenotic segments was significantly lower than that of nonstenotic segments, and the difference was statistically significant （P 〈 0.05）. 7ds after the operation, the SRE in stenotie segments significantly increased compared with that before the operation （ P 〈 0. 0 5 ） , while that in non-stenotic segments changed insignificantly （P 〉0.05）. 7d after the operation, SRE levels in stenotie and non-stenotic segments were similar （ P 〉 0.05）. △SRE % of stenotic segments and △VE at mitral orifice were positively correlated （r = 0.58, P 〈 0.05）, while △SRE% of nonstenotic segments and △VE at mitral orifice were insignificantly correlated （ r = 0.16, P 〉 0. 05）. Conclusion Application of strain rate imaging before and after placement of stents in coro- nary artery can accurately reflect the changes in the motion of the cardiac muscle of ventriculus sinister and the improving conditions of local myocardial function, and accurately evaluate the clinical therapeutic effects of placement of stents.