速度向量成像技术评价心脏再同步化治疗左室扭转与收缩同步性的关系

Relationship between left ventricular twist and systolic synchrony in patients with cardiac resynchronization therapy using velocity vector imaging

目的应用速度向量成像技术(VVI)探讨心脏再同步化治疗(CRT)患者左室扭转参数与收缩同步性的关系。方法选取慢性心力衰竭(简称心衰)行CRT患者,分别于术前,术后1、4个月采集患者左室短轴切面(二尖瓣水平、乳头肌水平、心尖水平)及心尖四腔心、两腔心和长轴切面的二维高帧频图像,运用Siemens Syngo WorkPlace软件测量不同短轴切面心底、心尖的旋转角度,最后计算左室扭转角度;观察不同时间点的QRS波时限、左室壁12节段达峰时间标准差(Ts-12-SD)、跨主动脉瓣血流时间速度积分(AVTI)、左室舒张末内径(LVEDV)、左室收缩末内径(LVESV)、左室射血分数(LVEF)及NYHA心功能分级、6 min步行距离(6MWT)和明尼苏达心衰生活质量评分。结果 30例患者成功完成11例CRT-P,19例CRT-D植入手术。术后LVEDV、LVESV、生活质量评分改善,QRS波变窄(P<0.001);LVEF、AVTI、6 MWT增加(P<0.001)。术后1、4个月时收缩期左室心尖部旋转角度峰值(PAr)、左室心底部旋转角度峰值(PBr)、左室扭转角度峰值(Ptw)较术前增大,差异均有显著性(P<0.01)。双变量Pearson直线相关分析结果显示,术前,术后1、4个月时Ptw(SM)和Ts-12-SD呈正相关性(分别为r=0.385、0.435、0.422,P均<0.05);与LVEF呈正相关性(分别为r=0.375、0.411、0.37,P均<0.05)。术前Ptw和术后1、4个月时的LVEF也呈正相关性(分别为r=0.379、0.375,P均<0.05)。而术前、术后1、4个月时的Ptw(SM)和Ts-12-SD与QRS波时限均无直线相关关系(P>0.05)。结论左心室扭转指标可准确评价左室的收缩同步性,可能为临床提供一种除Ts-12-SD外简便的新型评估方法。

Objective To investigate the relationship between left ventricular twist and systolic synchrony by velocity vector imaging（VVI） in patients with cardiac resynchronization therapy （CRT） device. Methods Thirty patients with congestive heart failure were enrolled and all of them underwent the CRT-P or CRT-D device. A series of comparisons were made among the preoperative , after one month and four months. Two-dimensional images were recorded from the left ventricular short-axis views （mitral valve level, papillary muscle level, apex level）. Myocardial rotation was quantitatively analyzed with a VVI offline software. Simultaneously, index including QRS width, peak systolic velocity of the 12 left ventricular segments（Ts-12-SD） , aortic velocity time integral （AVTI）, left ventricular ejection fraction （LVEF） , left ventricular at the end of diastole diameter（ LVEDV）, left ventricle at the end of systolic diameter（LVESV） and the classifications of NYHA, walking distance in the six minutes （6MWT）, the scores of life quality were recorded. Results Eleven CRT-P and nineteen CRT-D were accomplished. Compared with preoperation, LVEDV, LVESV and the score of life quality were significantly smaller（ P〈0.05）, simultaneously QRS was more narrow （ P〈0.001 ） and LVEF, AVTI, 6MWT were more incremental after the operation（P〈0.001 ）. In the aspect of peak apical rotation （PAr）, peak basal rotation （PBr） and peak twist （Ptw） in systole period were all larger than preoperation after one month and four months（P〈0.01 ）. It showed a positive correlation between Ptw（SM） and Ts-12-SD（r= 0 . 3 8 5,0.4 3 5,0.4 2 2, P 〈 0.0 5 respectively ） among preoperative, one and four months later; linear correlation between Ptw（SM） and LVEF （r=0. 375,0. 411, 0. 37, P〈0. 05 respectively ） among preoperative, one and four months later. Futhermore, a linear correlation between Ptw （preoperative） and LVEF （postoperative） （r=0. 379, 0. 375, P〈0. 041 respectively）. However, there were no linear correlation between Ptw（ SM ） and QRS width, Ts-12-SD and QRS width among the periods of preoperation, one and four months later after operation（ P〉0.05 ）. Conclusions The parameters of left ventricular torsion can evaluate left ventricular systolic synchrony accurately. It could be a new index for the efficacy assessment of CRT.