左右心室导线间距与心脏再同步治疗中即刻疗效的关系

目的探讨右心室起搏部位改变时，左、右心室导线间距对心脏再同步治疗（CRT）即刻疗效的影响。方法对25例符合适应证患者行CRT手术，术中将左心室导线植入侧壁或侧后壁，先后将右心室导线植入右心室流出道和右心室心尖部，分别测得主动脉速度血流积分及心肌收缩达峰时间标准差，同时比较此2种不同部位左、右心室导线间距，包括直接、垂直和水平距离（分别由正位及左侧位投影时测得）的差异。结果右心室心尖部起搏主动脉速度血流积分显著高于右心室流出道起搏（15．76±2．29）cm对（14．71±2．12）cm，P〈0．001]，QRS时限则显著较窄（141．84±20．89）ms对（159．84±19．56）ms，P〈0．001]。右心室心尖部起搏侧位投影下的导线间距（校正后）显著大于右心室流出道起搏（161．23±44．58）mm对（121．34±55．91）mm，P〈0．001]，其垂直距离（校正后）亦显著大于后者（97．65±45．73）mm对（39．41±23．51）mm，P〈0．001]。结论CRT术中改变右心室起搏部位时，侧位投影下的左、右心室导线间距较大者CRT手术即刻反应较佳。

Relationship between left ventricular-right ventricular interlead distance and acute hemodynamic re- sponse during cardiac resynchronization therapy

Objective To evaluate the relationship between interlead distance and acute response to cardiac resynchronization therapy （CRT） when right ventricular （RV） pacing site alters. Methods A total of 25 consecutive patients underwent CRT for standard indications. Left ventrieular （LV） lead was placed at the lateral or posterolateral wall.RV pacing site altered from RV outflow tract （RVOT）to RV apex （RVA）in the course of implantation.Aortic velocity time integral （aVTI）and standard deviation for time to peak velocity（ Ts- SD） were assessed during operation.A comparison was also made as for the LV-RV interlead distance ,including its vertical and horizontal components, on the posteroanterior and left lateral fluoroscopy views respectively.Re- suits Compared with RVOT pacing,a significantly higher aVTI （ 15. 76±2. 29） em vs. （ 14. 71±2. 12）cm, P〈0. 001 ] and narrower QRSdl （ 141.84±20. 89） ms vs. （ 159.84_± 19. 56） ms, P〈0. 001 ] could be obtained with RVA pacing.A significantly larger direct interlead distance（ which had been corrected）on the lateral fluo- roscopy view could also be observed with RVA pacing in comparison with RVOT pacing（ （ 161.23±44. 58） mm vs. （ 121.34±55.91 ） ram, P〈0. 001 ], so did the corrected vertical interlead distance （97.65±45.73） mm vs. （39. 41±23.51 ） mm ,P〈0. 001 ）. Conclusion A larger LV-RV intedead distance on lateral fluoroscopy view can result in better immediate response to CRT when RV lead position altered in the course of implantation.