射频消融慢径对房室结前传文氏周期的影响

Effects of slow pathway ablation on Wenkebach cycle lengths of atrioventricular node

目的:分析射频消融房室结慢径后对房室结前传文氏周期的影响。方法:67例房室结折返性心动过速患者,进行了选择性房室结慢径消融,除1例失败外,66例消融成功,其中45例消融后慢径不存在(Ⅰ组),12例消融后残存慢径前传功能(Ⅱ组)。结果:消融后快径有效不应期在Ⅰ组显著变短(331±74ms vs 271±77ms,P<0.001),在Ⅱ组无显著变化(346±49ms vs 314±50ms,P=NS)。房室结前传文氏周期消融前、后无显著变化(Ⅰ组352±60ms vs 337±71ms,P=NS;Ⅱ组350±48msvs 343±67ms,P=NS)。在Ⅰ组,消融前、后快径前传有效不应期与房室结前传文氏周期呈正相关(消融前 r=0.692,P<0.001;消融后 r=0.854,P<0.001)。在Ⅱ组,消融后慢径前传有效不应期与房室结前传文氏周期无相关性(r=0.497,P<0.10),快径前传有效不应期与房室结前传文氏周期呈正相关(r=0.838,P<0.002)。结论:射频消融慢径对房室结前传文氏周期影响不大,但明显使快径有效不应期缩短。

Objective:To analyze whether Wenckebach cycle length(WCL)of AV node could pro- long after ablation of slow pathway(SP),we evaluated change of WCL of AV node in patients underwent successful ablation of SP.Methods:Fifity-seven patients(18 male,39 female,mean age 50±13 years) with typical AV nodal reentrant tachycardia underwent SP ablation.After ablation,all patients had no in- ducible AVNRT.The SP has been completely eliminated in 45 cases(Group 1),12 patients had residual an- tegrade SP conduction(Group 2).Results:After ablation the effective refractory period(ERP)of fast pathway(FP)becarne shorter(from 331±74 ms to 271±77 ms,P<0.001)in group 1 patients,remained no change(346±49 ms vs 314±50 ms,P=NS)in group 2 patients.The WCL remained unchanged in both groups(group 1:352±60 ms vs 337±71 ms,p=NS;group 2:350±48 ms vs 343±67 ms,P=NS).The WCL had a positive correlation to the ERP of FP in group 1(r=0.629 before ablation,P<0.001;r=0. 845 after ablation,P<0.001).In group 2,WCI had no correlation(r=0.497,P>0.10)with the ERP of SP and a positive correlation(r=0.838,P<0.002)to the ERP of FP after ablation.Conclusion:Ra- diofrequency ablation of SP alone does not influence the WCL of AV node,but shorten the ERP of FP.