左心室心肌力学参数预测心脏再同步化治疗效果的临床研究

Prediction on effect of cardiac resynchronization therapy by mechanical parameters of left ventricular myocardium

目的应用三维斑点追踪技术(3D-STI)检测慢性心力衰竭患者心脏再同步化治疗(CRT)前后左心室心肌力学参数变化,评价并预测CRT疗效。方法接受CRT治疗的心力衰竭患者24例,于起搏器植入术前及术后3个月进行常规超声测量左室舒张末期容积(LVEDV)、收缩末期容积(LVESV)和射血分数(LVEF);采用3D-STI测量左心室整体面积应变(AS)和左心室整体扭转角度峰值(Twist)。比较术前和术后3个月各参数之间的差异,并将术后3个月LVEDV、LVESV、AS和Twist的改变量(△LVEDV、△LVESV、△AS和△Twist)与LVEF的改变量(△LVEF)进行相关性分析。将术后LVESV缩小≥15%定义为CRT治疗有效。结果 15例(62.5%)患者为CRT治疗有效组,9例(37.5%)为CRT治疗无效组。CRT术后,有效组的LVEDV、LVESV减小,LVEF增高,AS和Twist增强(P<0.05),而无效组各参数比较差异均未见统计学意义(P均>0.05);有效组术前AS和Twist大于无效组(P<0.05),其余参数比较差异未见统计学意义(P均>0.05);有效组术后LVEDV和LVESV较无效组减小,LVEF增高,AS和Twist增强(P<0.05)。相关分析结果显示△AS和△Twist与△LVEF均有良好相关性(r=-0.493、0.521,P<0.05)。结论三维斑点追踪技术检测的左心室心肌力学参数AS和Twist可准确评价和预测CRT疗效,为临床筛选合适患者提供重要的超声依据。

Objective To investigate the changes of mechanical parameters of left ventricular myocardium before and after cardiac resynchronization therapy（ CRT） in patients with chronic heart failure by three-dimensional speckle tracking technology（ 3D-STI）,to evaluate and predict the efficacy of CRT. Methods Twenty-four patients with congestive heart failure received the CRT,their left ventricular end-diastolic volume（ LVEDV）,left ventricular end-systolic volume（ LVESV） and left ventricular ejection fraction（ LVEF） were measured by conventional ultrasonography before and 3 months after CRT operation. The left ventricular global area strain（ AS） and the peak of left ventricular twist angle（ Twist） were measured by 3D-STI. The differences of all the indices between before CRT and 3 months after CRT were calculated and the correlation between the changes of all those indices and the changes of left ventricular ejection fraction（ △LVEF） were analyzed. Patients were divided into responders and non-responders based on a reduction over 15% in LVESV after CRT.Results Among 24 patients,15 cases of them were responders,9 cases of them were non-responders. Three months after CRT,the responders LVEDV,LVESV reduced,LVEF increased,AS and Twist enhanced（ P〈0. 05）,while the non-responders all parameters were not significantly different（ P〈0. 05）. Compared with non-responders,the responders before CRT demonstrated a significant increase of AS and Twist（ P〈0. 05）; 3 months after CRT,LVEDV,LVESV reduced,LVEF increased,AS and Twist enhanced（ P〈0. 05）. △AS and △Twist were correlated with △LVEF 3 months after CRT（ r =-0. 493,0. 521; P〈0. 05）. Conclusions Left ventricular mechanical parameters（ AS and Twist） measured by 3D-STI,which not only can accurately evaluate the efficacy of CRT,but also can predict the efficacy,provide important basis for chinical screening suitalde patients.