射频消融治疗局灶性房颤面临的问题及术中应用心腔内超声的重要性

目的　讨论射频消融治疗局灶性心房颤动 (房颤 )中面临的问题 ,评价心腔内超声在术中的价值。方法　比较 5例分别经X线指引及心腔内超声指引下射频消融局灶性房颤的治疗结果、手术时间、X线曝光时间 ,研究术中存在的问题 ,探讨解决方法。结果　 (1) 5例病人即刻成功 3例 ;其中 1例于 2 4小时后复发。未成功的 2例中 ,1例经 3个月的随访无房颤发作 ;(2 )心脏内超声指导操作 ,与X线指导相比 ,手术时间短 ,X线曝光量少 ,可清楚显示房间隔、肺静脉的切面 ,有助于准确进行房间隔穿刺及调整导管的定位及消融 ;(3)术中面临的主要问题是很难诱发房颤 ,判断与房颤相关的房早以及消融的终点存在较大的主观性 ;(4 ) 1例单纯经心腔内超声指引下行房间隔穿刺 ,在送入鞘管后出现心包填塞。心腔内超声结合X线影像技术有助于减少并发症。结论　射频消融治疗局灶性房颤是一个有希望的治疗手段。超声指导导管操作及定位具有重要意义 ,但仍存在一些技术问题需进一步解决。目前 ,应注意掌握适应证 ,以保证操作的安全有效性

The importance of intracardiac echocardiography and difficulties confronted in procedure of radiofrequency ablation for focus atrial fibrillation

Objective To evaluate the intracardiac echocardiography in guiding the radiofrequency ablation for focus atrial fibrillation and discuss the problems confronted in this procedure.Methods 5 patients with focus atrial fibrillation accepted electrophysiologic study and radiofrequency ablation,1 guided by X-ray combining intracardiac mapping,the other guided by intracardiac echocardiography.Efficacy of the procedure,time for operation and X-ray exposure were compared.Results (1)Of the 5 patients,3 got immediately successful results,2 failed to the procedure.Atrial fibrillation recovered in 24 hours after ablation in 1 patient who has got success immediately.Delayed success occurred in 1 patient without relapse 3 months later.(2)Compared with the X-ray guiding method,intracardiac echocardiography can clearly show the interatrial septum and pulmonary vein.These properties are helpful to guiding the puncture septum and ablation around the ostium of pulmonary vein accurately,and also can save operative time and decrease the exposeure to the X-ray.(3)The two main difficulties encountered when searching for this type of focal source,however,are patients with too few atrial premeature beats and no episode of atrial fibrillation initiated by one ectopic beat at base state and isoprotenol infusion combined with burst atrial pacing.(4)1 patient who accepted intracardiac echocardiography guiding method suffered a tamponade after advancing the transseptum sheath.Echocardiography combined with X-ray may be helpful to avoid this complication.Conclusion Radiofrequency ablation is a hopeful method to cure the focus atrial fibrillation, intracardiac echocardiography is important to direct the ablation catheter accurately.At present,selecting proper patients for this procedure is very important because some obstacles lie in the procedure and need to be solved.