减少术中X线曝光剂量治疗阵发性室上性心动过速

Reducing radiation dose during catheter ablation of paroxysmal supraventricular tachycardia

目的 分析阵发性室上性心动过速（PSVT）不同射频消融策略的X线曝光剂量,探索减少术中X线曝光剂量的方法.方法 2013年6月至10月156例在阜外心血管病医院接受射频消融的PSVT患者,根据术者不同分为A、B两组,两组均采用相同的优化后的低剂量透视条件.A组74例,为常规X线透视下行电生理检查及射频消融;B组82例,采用三维标测系统（Ensite-NavX）结合X线透视进行射频消融,术中缩小X线透视窗.记录患者的累积入射剂量（CD）、剂量面积乘积（DAP）、透视时间并换算单位时间放射剂量.结果 A组的累积入射剂量、剂量面积乘积、透视时间分别为22.0（12.0 ～34.0）mGy,130.0（66.7～237.7）μGym^2,16.3（11.1 ～26.0）min.B组的累积入射剂量、剂量面积乘积、透视时间分别为6.5（3.0～12.2）mGy,39.5 （20.8 ～ 76.5）μGym^2,6.2（3.5～9.1）min.与A组相比,B组在累积入射剂量、剂量面积乘积、透视时间上均明显降低（P值均＜0.001）.校正透视时间后,A、B两组累积入射剂量比率分别为1.13（0.81～1.98） mGy/min,1.11 （0.67～1.77） mGy/min,两组间差异无统计学意义（P=0.396）,剂量面积乘积比率分别为8.85 （5.91 ～ 12.76） μGym^2/min,6.23（3.93 ～10.04） μGym^2/min,B组明显低于A组（P=0.007）.结论 采用三维电场导航系统并缩小X线透视窗,可以明显减少PSVT术中X线曝光剂量.

Objective To analyse the X ray radiation dose by two ways of radiofrequency catheter ablation（RFCA） in the procedure of paroxysmal supraventricular tachycardia（PSVT）,and present a protocol of low radiation exposure.Methods One hundred and fifty-six patients undergoing ablation of PSVT from June 2013 to October 2013 were included and divided into group A and group B according to the operator.A same fluoroscopy system which provided a low radiation dose through optimizing the parameter settings was used.Patients of group A（n =74） were performed by one interventional electrophysiologist,who instituted a practice of traditional fluoroscopic condition and did not minimize the fluoroscopy field specially.Patients of group B （n =82） were performed by another electrophysiologist,who was guided by fluoroscopy and Ensite-NavX electroantomic mapping and kept the fluoroscopy field to minimum.After the procedure,cumulative radiation dose （CD）,dose area product （DAP） and fluoroscopy time were measured,then the radiation dose per unit time was calculated.Results Compared with group A,The CD,DAP and fluoroscopy time were significantly reduced in group B from a median of 22.0 mGy to 6.5 mGy（P〈0.001）,130.0 μGym^2 to 39.5 μ Gym^2 （P〈0.001） and 16.3min to 6.2min（P〈0.001）.After correcting fluoroscopy time,no significant difference was found between two groups in CD per unit time（1.13 mGy/min vs.1.11 mGy/min,P=0.936）,DAP per unit time was significantly reduced in group B from 8.85 μGym^2/min to 6.23 μ Gym^2/min （P =0.007）.Conclusion The radiation exposure can be significantly reduced in the ablation of paroxysmal supraventricular tachycardia by combining fluoroscopy with electroantomic mapping and minimizing the fluoroscopy field.