峡部隐匿性拖带指导典型心房扑动的射频消融治疗

The Significance of Isthmus Concealed Entrainment in the Radiofrequency Catheter Ablation of Common Atrial Flutter

目的 :研究右房峡部隐匿性拖带在典型心房扑动 (房扑 )患者射频消融中的意义。方法 :对 12 5例行射频消融治疗的典型房扑患者研究。消融前或消融失败后 ,短阵快速心房刺激诱发房扑 ,在下腔静脉至三尖瓣环之间的峡部以短于房扑周长 10～2 0ms的周长拖带房扑 ,观察心房刺激波的形态 ,并测量起搏后间期。然后线性消融峡部。结果 :所有房扑均于峡部呈隐匿性拖带 ,且起搏后间期等于房扑周长 (PPI=FCL)。 118例患者 ( 94 .4 % )常规射频消融成功产生了峡部的双向传导阻滞 ,而 7例患者( 5 .6% )射频消融失败。对该 7例患者再次于峡部进行房扑的拖带研究 ,均显示房扑呈隐匿性拖带 ,且PPI =FCL。换用冷盐水灌注导管消融 ,平均消融 4 .5± 2次后均获成功。表明典型房扑患者常规射频消融不能成功的原因是由于射频消融不能产生足够的组织破坏。结论 :峡部隐匿性拖带有助于发现射频消融不能成功的机制 。

Objective: Concealed entrainment with PPI=FCL (PPI: post pacing interval, FCL: flutter cycle length) delineated that the pacing site was in the reentry circuit , as would be invaluable in guiding radiofrequency (RF) ablation of atrial flutt er (AF). The study investigated the role of isthmus concealed entrainment in gui ding RF ablation of common type AF. Methods: One hundred and twenty-five cases wi th common AF were enrolled. Isthmus entrainment of AF was studied before ablatio n and after initial failure of ablation, the isthmus was then linearly ablated f rom tricuspid to the inferior vena cava. Results: All the cases demonstrated isth mus concealed entrainment of AF with PPI = FCL. Isthmus bidirectional block was successfully created in 118 patients, but failed in 7 patients by the convention al RF energy applications. Isthmus concealed entrainment was reestablished in th ese 7 patients, and the saline-irrigated cool-tipped catheter was introduced. Th e 7 cases were succeeded with a mean RF energy application of 4.5+/-2 times. It revealed that the failed achievement of isthmus bi-directional block in common A F was due to the inadequate tissue injury. Conclusion: Isthmus concealed entrainm ent is able to focus the cause of failure, and play an important role in guid ing RF ablation of common AF.