Analysis of atrioventricular function and its efficacy in patients with AVNRT undergoing atrioventricular junction ablation of slow conduction pathway

Objective The electrophysiological parameters of atrioventricular conduction function in patients with atrioventricular nodal reentry tachycardia (AVNRT) were analyzed, and to explore the effect of different ablation endpoints on atrioventricular conduction function in patients with AVNRT. Methods 96 cases with AVNRT underwent radiofrequency catheter ablation (RFCA) of slow conduction pathway.According to whether the slow pathway eliminated, the patients were divided into the slow pathway disappeared group and slow tracks remaining group.Preoperative and postoperative intracavitary electrophysiological examination and atrioventricular function data were recorded, including before and after radiofrequency ablation of bundle of HIS, PA, AH, HV interval, atrioventricular prequel venturi point(AVN-WKB), ventriculoatrial retrograde venturi point(VAN-WKB), atrioventricular node prequel effective refractory period(AVB-WKB). Patients were followed up by telephone for a year.Then, a comparative analysis of preoperative and postoperative was done. Results RFCA of AVNRT patients with atrioventricular node prequel time effect: RFCA and preoperative ratio, after his bundle electrogram PA, ah, HV interval had no significant changes(P>0.05). Effect of RFCA surgery on patients with AVNRT refractory atrioventricular node prequel: compared with RFCA before surgery, postoperative slow pathway disappear fast pathway shortening of effective refractory period[preoperative(287.5±46.2)ms, postoperative(260.2±55.6)ms, t=2.901, P=0.005], slow pathway effective refractory period[disappear preoperative(243.3±43.2), postoperative(0.0±0.0)ms, t=43.290, P=0.000], AV node Wenckebach point in advance before operation[(261.3±44.3)ms, postoperative(293.2±46.2)ms, t=3.828, P=0.000]; group after slow pathway to improve fast pathway effective refractory period without obvious change(P>0.05), the slow pathway effective refractory period in high concentration[preoperative(242.2±42.8)ms, postoperative(281.2±41.3)ms, t=3.879, P=0.000], atrioventricular node Wenckebach point in advance before operation[(261.5±43.5)ms, postoperative(291.3±46.5)ms, t=2.769, P=0.007]. Comparison between groups, after slow pathway disappeared group fast pathway effective refractory period was significantly shorter in the slow diameter improvement group, but between the two groups in the atrioventricular node Wenckebach point differences was not statistically significant(P>0.05). There was no recurrence in the follow-up after a year of slow path loss and slow pathway. Conclusion RFCA caused by slow pathway to disappear or modified two slow pathway ablation right AVNRT patients atrioventricular time had no effect, but all the atrioventricular junction the prequel's point advance.The atrioventricular node slow pathway disappear fast and effective pathway refractory period shortened, slow pathway improved the slow pathway effective refractory period.RFCA surgery done by the slow pathway disappeared or slow pathway ablation is effective in patients with AVNRT, and there was no significant recurrence rate in both groups within 1 year. Key words: Ablation; Tachycardia; Atrioventricular conduction function