Early Results of Complex Fractionated Atrial Electrogram Mapping Guided Atrial Fibrillation Surgery

OBJECTIVE: Although the Cox-maze operation is the standard surgical procedure for permanent atrial fibrillation(AF), conversion to sinus rhythm is limited by patient characteristics, including the duration of AF, atrial size, and voltage of fibrillation waves. A surgical strategy based on structural alteration of the electrical substrates of AF is required to achieve better outcomes of AF surgery. Complex fractionated atrial electrogram (CFAE) plays an important role in the electrical substrate of AF. We performed AF surgery guided by preoperative CFAE mapping using a 3-dimensional (3D) mapping system. This study evaluated the early results of our procedure.

METHODS: From January 2015 to August 2016, 8 patients (mean age:66.5±6.4 years) underwent CFAE mapping-guided AF surgery. In the preoperative electrophysiological study using 3D mapping, CFAE was defined by a low voltage electrogram (0.05~0.25 mV) with a highly fractionated potential (short cycle length <120 msec). First, right atrial CFAE sites were ablated by using a catheter ablation system. Several days after right-sided CFAE ablation, a modified Cox-maze operation was performed with additional cryoablation of CFAE sites.

RESULTS: There were 1~3 (mean:2.5 ±0.8) CFAE sites in the right atrium and 2~4 (mean:2.4±0.7) sites in the left atrium. Mean CFAE mapping time was 87.6±24.6 minutes, fluoroscopy time was 53.1±22.2 minutes, and volume of contrast agent was 44±3 ml. Concomitant cardiac surgery included mitral valve plasty in 6 patients, and aortic valve replacement and mitral valve replacement in 1 patient each. The mean time for CFAE mapping-guided AF surgery was 25.7±5.6 minutes. At discharge, 7 patients were in sinus rhythm and 1 patient still had AF, but sinus rhythm recovered at 3 months postoperatively without anti-arrhythmic medication. After a mean follow-up of 11.7±8.5 months, all patients remained in sinus rhythm.

CONCLUSIONS: Early results suggest that CFAE mapping-guided atrial fibrillation surgery is feasible and effective. Although the long-term effect of CFAE ablation on maintenance of sinus rhythm and atrial function should be evaluated, this novel method could provide an alternative strategy for the surgical treatment of AF.