Chilukuri Karuna, Scherr Daniel, Dalal Darshan, Cheng Alan, Spragg David, Nazarian Saman, Barcelon Bernadette D, Marine Joseph E, Calkins Hugh, Henrikson Charles A
Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
J Interv Card Electrophysiol. 2011 Nov;32(2):137-46. doi: 10.1007/s10840-011-9587-8. Epub 2011 May 26.
Esophageal injury is a potential complication with radiofrequency ablation in the posterior wall of the left atrium (LA). The "box isolation" method isolates the posterior LA wall including the pulmonary veins without ablation on the posterior LA wall. This study compares the acute and long-term efficacy of the box isolation method with conventional circumferential pulmonary vein isolation (PVI) for catheter ablation of AF.
Twenty-nine patients (age 60 ± 9 years, 62% male, 79% paroxysmal) with drug refractory AF underwent catheter ablation. Sixteen of the 29 patients (55%) underwent box isolation. Recurrence of AF was detected by checking the daily recorded rhythm strip on a portable home ECG monitor, irrespective of the symptoms. Mean follow-up duration was 10 ± 2 months.
Complete isolation of the posterior LA using box isolation lesions was achieved in three of 16 (19%) patients. The other 13 patients underwent creation of additional lesions until all PVs were isolated. Of the 16 patients who underwent box isolation, four patients (25%) had complete success, six patients (38%) had improvement, and the remaining six patients (37%) had failure. Of the 13 patients who underwent the standard PV isolation, two patients (15%) had complete success, eight patients (62%) had improvement, and the remaining three patients (23%) had failure (p = 0.44).
In this pilot study, the efficacy of box isolation is similar to the circumferential PVI for catheter ablation of AF. Few patients achieved PVI with box method alone. Based on these results, we do not recommend the box isolation strategy.
食管损伤是左心房后壁射频消融的潜在并发症。“盒状隔离”方法可隔离包括肺静脉在内的左心房后壁，而不对左心房后壁进行消融。本研究比较了盒状隔离方法与传统环肺静脉隔离术（PVI）用于房颤导管消融的急性和长期疗效。
29例药物难治性房颤患者（年龄60±9岁，男性占62%，阵发性房颤占79%）接受了导管消融。29例患者中有16例（55%）接受了盒状隔离。通过检查便携式家用心电图监测仪上每日记录的心律条来检测房颤复发，无论有无症状。平均随访时间为10±2个月。
16例患者中有3例（19%）通过盒状隔离病变实现了左心房后壁的完全隔离。其他13例患者进行了额外病变的创建，直到所有肺静脉都被隔离。在接受盒状隔离的16例患者中，4例（25%）完全成功，6例（38%）有改善，其余6例（37%）失败。在接受标准肺静脉隔离的13例患者中，2例（15%）完全成功，8例（62%）有改善，其余3例（23%）失败（p = 0.44）。
在这项初步研究中，盒状隔离的疗效与环肺静脉隔离术用于房颤导管消融的疗效相似。很少有患者仅通过盒状方法实现肺静脉隔离。基于这些结果，我们不推荐盒状隔离策略。
