The Clinical Observation Of Voltage Gradient Mapping Guide In Ablation Of Atrioventricular Nodal Reentry Tachycardia

Objective: Ablation of atrioventricular nodal reentry tachycardia(AVNRT)is the most common supraventricular tachycardia inducible in the electrophysiology lab。AVNRT has become more and more high success and low complication rate through the ablation of atrioventricular node slow pathway.Now most ablations are successful in utilizing an atrioventricular node anatomic approach and potential positioning in combination with ablation catheter,but heart anatomic variance,unusual pathway locations,or multiple pathways may complicate the procedure and reduce the success rate.Visualization of the slow pathway could expedite ablation success and enhance safety.Comparing with the routine anatomy and potential positioning method blation guided by the CARTO 3 electroanatomic mapping system,our purpose is to determine whether voltage gradient mapping can directly image the slow pathway and aid successful ablation of AVNRT.Methods: 77 patients who had been diagnosed as AVNRT with conventiona lelectrophysiological testing were enrolled In February 2015 to October,they were hospitalized in Yijishan Hospital Affiliated with Wannan Medical College.57 patients with the routine anatomy and potential positioning method blation guided by the CARTO 3 electroanatomic mapping system。20 patients with a 3-D reconstruction of the atrial endocardial geometry was created by contact voltage mapping.Peak-to-peak voltage data were collected during sinus rhythm using ablation catheter of the righ tatrium,paying particular attention to collection of data from the atrial septum within the triangle of Koch.Ablate the slow pathway associated low-voltage bridges.Followingablation,a repeat voltage gradient map was performed.All patients are induced with isuprel infusion and conduct regular heart electrophysiological examination.The study endpoint was the loss of antegrade slow pathway function and the absence of consistent AV nodal echo beats.Results: In this study,Immediate success was achieved in all 77 patients with radiofrequency ablation,without complications.20 patients with a 3-D reconstruction of the atrial endocardial geometry was created by contact voltage mapping,Voltage values were adjusted until low-voltage bridging was observed within the Triangle of Koch.Ablation of the slow pathway associated low-voltage bridges in all patients was successful in preventing reinduction.Repeat mapping confirmed the absence of lowvoltage connections previously observed.Comparing with the voltage gradient mapping group and traditional electrical dissection group,total operation time,X-ray exposure quantity,X-ray exposure time and the discharging number were no significant statistical difference.Conclusion: Voltage gradient mapping can assist in visualization of the slow pathway.Ablation of the associated low-voltage bridge results in loss of slow pathway function and significant changes in the post-ablation voltage map.Comparing with the routine anatomy and potential positioning method blation guided by the CARTO 3 electroanatomic mapping system,the voltage gradient mapping offers the feasibility to target the slow pathway for successful ablation and is not inferior to the former.For ablating a heart disease anatomic variance and AVNRT,the voltage gradient mapping may show a certain superiority in clinical work of supplementary treatment.