Becker Michael, Hoffmann Rainer, Schmitz Fabian, Hundemer Anne, Kühl Harald, Schauerte Patrick, Kelm Malte, Franke Andreas
Department of Cardiology, University RWTH Aachen, Aachen, Germany.
Am J Cardiol. 2007 Dec 1;100(11):1671-6. doi: 10.1016/j.amjcard.2007.07.019. Epub 2007 Oct 24.
We sought to define the impact of echocardiographically defined left ventricular (LV) lead position on the efficacy of cardiac resynchronization therapy (CRT) in a serial study using 3-dimensional echocardiography. Fifty-eight consecutive patients (53+/-9 years of age; 37 men) with heart failure were included in the study. Echocardiograms were obtained before CRT, within 7 days after implantation, and at 12+/-2 months of follow-up using a 3-dimensional digital ultrasound scanner (iE33, Philips, Andover, Massachusetts). Analysis of the temporal course of contraction in 16 LV segments was performed offline using a semiautomatic contour tracing software (LV Analysis, TomTec, Unterschleissheim, Germany). Based on the resulting volume/time curves the segment with the latest minimum of systolic volume in each patient was identified preoperatively (segment A). In addition, the temporal difference between the pre- and postoperative (within 7 days) minimum of systolic volume was determined for each segment. The segment with the longest temporal difference was defined to show the greatest effect of CRT. Location of the LV lead tip was assumed to be within this segment (segment B). LV lead position was defined as optimal when segments A and B were equal and as nonoptimal when they were far from each other. Using this definition, 26 patients had a nonoptimal and 32 patients an optimal LV lead position. Before CRT ejection fraction (32+/-4% vs 31+/-6%), LV end-systolic and end-diastolic volumes (242+/-92 vs 246+/-88 ml, 315+/-82 vs 323+/-90 ml), and peak oxygen consumption (14.3+/-1.4 vs 14.6+/-1.5 ml/min/kg) were equal in the 2 groups. At 12+/-2 months of follow-up, patients with an assumed optimal LV lead position showed greater increases of ejection fraction (10+/-2% vs 6+/-3%) and peak oxygen consumption (2.4+/-0.3 vs 1.5+/-0.4 ml/min/kg) and greater decreases of LV end-systolic (32+/-7 vs 21+/-5 ml) and end-diastolic (20+/-7 vs 13+/-6 ml) volumes. In conclusion, correspondence of the segment with the latest preoperative LV contraction with the segment with the greatest effect based on CRT results in a significantly greater benefit of ejection fraction and peak oxygen consumption and a greater improvement in LV remodeling. Thus, there is an optimal LV lead position that should be obtained.
我们试图在一项使用三维超声心动图的系列研究中，确定经超声心动图定义的左心室（LV）导联位置对心脏再同步治疗（CRT）疗效的影响。该研究纳入了58例连续的心力衰竭患者（年龄53±9岁；男性37例）。在CRT治疗前、植入后7天内以及随访12±2个月时，使用三维数字超声扫描仪（iE33，飞利浦，安多弗，马萨诸塞州）获取超声心动图。使用半自动轮廓追踪软件（LV Analysis，TomTec， Unterschleissheim，德国）离线分析16个左心室节段的收缩时间过程。根据所得的容积/时间曲线，术前确定每位患者收缩容积最小最晚的节段（节段A）。此外，确定每个节段术前与术后（7天内）收缩容积最小值之间的时间差异。时间差异最长的节段被定义为显示CRT效果最大的节段。LV导联尖端的位置假定在该节段内（节段B）。当节段A和节段B相等时，LV导联位置被定义为最佳；当它们彼此远离时，则为非最佳。根据这一定义，26例患者的LV导联位置非最佳，32例患者的LV导联位置最佳。CRT治疗前，两组患者的射血分数（32±4%对31±6%）、左心室收缩末期和舒张末期容积（242±92对246±88 ml，315±82对323±90 ml）以及最大耗氧量（14.3±1.4对14.6±1.5 ml/min/kg）相等。在随访12±2个月时，假定LV导联位置最佳的患者射血分数（10±2%对6±3%）和最大耗氧量（2.4±0.3对1.5±0.4 ml/min/kg）增加更多，左心室收缩末期（32±7对21±5 ml）和舒张末期（20±7对13±6 ml）容积减少更多。总之，术前左心室最晚收缩节段与基于CRT结果效果最大的节段相对应，可使射血分数和最大耗氧量显著获益更多，左心室重构改善更大。因此，应获得最佳的LV导联位置。
