Mitrani R D, Klein L S, Hackett F K, Zipes D P, Miles W M
Krannert Institute of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis 46202-4800.
J Am Coll Cardiol. 1993 Feb;21(2):432-41. doi: 10.1016/0735-1097(93)90686-u.
We compared the electrophysiologic effects on atrioventricular (AV) node physiology of selective "fast" versus selective "slow" pathway radiofrequency ablation in 42 patients with drug-resistant AV node reentrant tachycardia who underwent 51 ablation attempts to prevent tachycardia recurrence while preserving AV conduction.
The recent introduction of radiofrequency ablation to treat AV node reentrant tachycardia allows the opportunity to study the effects of selective elimination of the different limbs involved in AV node reentrant tachycardia.
Selective fast pathway ablation was attempted in 13 patients by delivering radiofrequency energy anteriorly across the tricuspid valve anulus. Selective slow pathway ablation was attempted in 29 patients by delivering radiofrequency energy posteriorly across the tricuspid valve anulus at sites where putative slow pathway potentials were recorded.
Selective fast pathway ablation eliminated AV node reentrant tachycardia without AV block in 6 (46%) of 13 patients after one ablation session and in an additional 3 patients (69% of total) after repeat ablation sessions. Slow pathway ablation eliminated AV node reentrant tachycardia without AV block in 26 (90%) of 29 patients after one radiofrequency ablation session and in an additional 2 patients (97% of total) after repeat ablation sessions. Selective fast pathway ablation increased the PR interval (140 to 220 ms, p = 0.0001) and AH interval (66 to 153 ms, p = 0.0001), whereas slow pathway ablation did not change these intervals. Fast pathway radiofrequency ablation caused retrograde block in 7 (64%) of 11 patients, whereas no patients undergoing slow pathway ablation developed selective retrograde block. Single AV node echo beats were commonly induced after slow but not fast pathway ablation (17 of 29 patients vs. 1 of 11 patients, respectively, p = 0.01) and did not predict recurrence of AV node reentrant tachycardia.
Successful selective radiofrequency ablation of fast or slow pathways in patients with AV node reentrant tachycardia resulted in different electrophysiologic properties after ablation. Slow pathway ablation produced more successful outcomes, with a decreased prevalence of recurrent AV node reentrant tachycardia or AV block.
我们比较了42例药物难治性房室结折返性心动过速患者中，选择性“快”径路与选择性“慢”径路射频消融对房室（AV）结生理功能的电生理影响。这些患者共接受了51次消融尝试，目的是预防心动过速复发并保留房室传导。
最近引入的射频消融治疗房室结折返性心动过速，为研究选择性消除参与房室结折返性心动过速的不同径路的影响提供了机会。
对13例患者尝试通过经三尖瓣环前方施加射频能量进行选择性快径路消融。对29例患者尝试通过在记录到假定慢径路电位的部位经三尖瓣环后方施加射频能量进行选择性慢径路消融。
13例患者中，6例（46%）在一次消融术后通过选择性快径路消融消除了房室结折返性心动过速且无房室传导阻滞，另外3例患者（占总数的69%）在重复消融术后也达到此效果。29例患者中，26例（90%）在一次射频消融术后通过慢径路消融消除了房室结折返性心动过速且无房室传导阻滞，另外2例患者（占总数的97%）在重复消融术后也达到此效果。选择性快径路消融使PR间期（从140毫秒增至220毫秒，p = 0.0001）和AH间期（从66毫秒增至153毫秒，p = 0.0001）增加，而慢径路消融未改变这些间期。快径路射频消融使11例患者中的7例（64%）出现逆行阻滞，而接受慢径路消融的患者中无一例发生选择性逆行阻滞。慢径路消融后较常诱发单个房室结回波搏动（29例患者中有17例，而11例患者中有1例，p = 0.01），而快径路消融后则不然，且单个房室结回波搏动并不能预测房室结折返性心动过速的复发。
房室结折返性心动过速患者成功进行选择性快径路或慢径路射频消融后，消融后的电生理特性有所不同。慢径路消融产生了更成功的结果，房室结折返性心动过速复发或房室传导阻滞的发生率降低。
