心房颤动环肺静脉口外线性消融术后二次消融的电生理发现及随访结果

Electrophysiological findings and ablation strategies in patients with atrial tachyarrhythmias after left atrial circumferential ablation in the treatment of atrial fibrillation

目的介绍三维导航下环肺静脉口外线性消融治疗心房颤动(房颤)术后快速房性心律失常及房颤复发患者二次消融时的电生理发现、消融策略及随访结果。方法 2004年4月至2006年5月,采用左心房线性消融治疗房颤共91例。术后4例患者因心动过速反复发作或无休止发作于2周内行二次消融术。随访3个月后,25例患者有快速性心律失常发作,其中15例接受二次消融术。在所有接受二次消融的19例患者中,第一次消融前房颤为阵发性者11例,持续性2例,永久性6例,其中男性17例,女性2例,年龄25～65(53±12)岁。所有患者术中均使用环状电极行肺静脉电位探查。结果 5例患者发现窦律下左侧肺静脉延迟电位,1例出现右侧肺静脉延迟电位,2例患者双侧同时出现延迟肺静脉电位;此类患者于环状电极指导下标测原消融线径的传导"缺口"并再次隔离成功。3例患者左侧肺静脉内颤动样节律,递减传导至左心房出现不规则房性心动过速;此类患者再次于三维标测指导下行左侧环状消融隔离成功;1例患者左侧肺静脉心动过速并1:1传导至左心房,经终止心动过速后隔离成功。4例患者肺静脉探查未发现肺静脉电位,但诱发出其他心动过速,包括右房瘢痕性房性心动过速、隐匿性旁路介导的室上性心动过速、右后间隔局灶性房性心动过速及三尖瓣峡部依赖的心房扑动。此4例患者在常规标测和三维标测指导下,心动过速均被成功消融。术中呈房颤节律者3例,再次于三维标测指导下行环肺静脉线性消融获成功。平均随访4～26(11.5±8.5)个月,16例患者无快速性心律失常发作,1例有频繁房性早搏,1例永久性房颤患者仍呈房颤节律,另1例永久性房颤患者转为阵发性房颤。结论肺静脉与左心房之间电传导恢复是消融术后出现快速房性心律失常的主要因素。肺静脉以外的心动过速在左心房线性消融术后可以表现为独立的心动过速,也可以触发房颤;环肺静脉口外线性消融不足以完全改良永久性房颤的维持基质。

Objective To report the electrophysiological findings and the ablation strategies in patients with atrial tachyarrhythmias （ATAs） or atrial fibrillation （AF） recurrence after left atrial circumferential ablation （LACA） in the treatment of AF. Methods 91 patients with AF had LACA procedure from April 2004 to May 2006, 19 of which accepted the second ablation procedure due to ATAs or AF recurrence. In all the 19 patients [17 male, 2 female, age 25 - 65 （53 ±12） years], 11 presented with paroxysmal AF before the first ablation procedure, 2 with persistent AF and 6 with permanent AF. Pulmonary vein potentials （PVP） were investigated in both sides in all the patients. Results Delayed PVP was identified inside the left circular line in 5 patients, in the right in 1 and both in 2 during sinus rhythm. ＂Gap＂ conduction was found and successfully closed guided by circular mapping catheter. In 3 cases, irregular left atrial tachycardia was caused by fibrillation rhythm inside the left ring via decremental ＂ gap＂ conduction. Reisolation was done successfully again guided by 3-D mapping and made the left atrium in sinus rhythm but the fibrillation rhythm was still inside the left ring. Pulmonary vein tachycardia with 1 ： 1 conduction to the left atrium presented in one case and reisolation stopped the tachycardia. No PVP was discovered in both sides in 4 patients but other tachycardias could be induced, including two right atrial scar related tachycardias, two supraventricular tachycardias mediated by concealed accessory pathway, one cavotricuspid isthmus dependent atrial flutter and one focal atrial tachycardia near the coronary sinus ostium. All the tachycardias in these 4 patients were successfully ablated with the help of routine and 3-D mapping techniques. In the rest 3, which were in AF rhythm, LACA was successfully done again. After a mean follow-up of 4 -26 （11.5 ± 8.5） months, 16 patients were symptom free without anti-arrhythmic drug therapy; 1 of them had frequent palpitation attack with Holter recording of atrial premature contractions ; 2 of them with permanent AF became paroxysmal in one, and still in AF in the other. Conclusions Reconduction between the left atrium and the pulmonary veins is the dominant factor for post-LACA ATAs and AF recurrence. Other forms of atrial tachycardias or supraventricular tachycardias may coexist with AF or sometimes trigger AF. LACA can not sufficiently modify AF substrate in some permanent AF patients.