Atrial arrhythmia recurrence after the Maze procedure: Insights from catheter-based mapping.

BACKGROUND

The Cox-Maze procedure treats atrial fibrillation (AF) through surgical lesion sets designed to isolate pulmonary veins (PVs) and interrupt atrial reentrant circuits.

OBJECTIVE

This study aimed to characterize mechanisms of recurrent atrial arrhythmias after Maze procedures using electroanatomic mapping.

METHODS

We retrospectively analyzed 86 patients who underwent Maze procedures from 2008 to 2023 and later required endocardial catheter ablation for recurrent AF or atrial flutter (AFl). Electroanatomic mapping assessed lesion integrity, arrhythmia patterns, and ablation outcomes.

RESULTS

After the 3-month postoperative blanking period, 31.8% of patients had both AF and AFl recurrence, 33.7% had AF only, and 33.7% had AFl only. PV reconnection occurred in 78.3% of patients who initially underwent PV isolation. Reconnection rates were significantly lower with cut-and-sew Maze III (5%) than cryothermal (67%; odds ratio 0.07; P < .0001) and radiofrequency ablations (56%; odds ratio 0.11; P < .0001). Macroreentrant flutter was inducible in 77.9% of patients during catheter mapping, frequently associated with incomplete linear lesions. Surgical left atrial appendage-to-mitral annulus lesions were associated with significantly higher overall flutter (100% vs 71.2%; P = .005), left AFl (80% vs 36.4%; P = .001), and atypical flutter (90% vs 50%; P = .002). Mitral valve repair correlated with increased overall flutter (92.6% vs 71.2%; P = .028), cavotricuspid isthmus flutter (55.6% vs 30.5%; P = .033), and atypical flutter (81.5% vs 49.2%; P = .005).

CONCLUSION

Recurrent arrhythmias after Maze primarily result from PV reconnection and incomplete linear lesions. Cut-and-sew lesions demonstrate greater durability than thermal ablation. Meticulous lesion formation and intraoperative verification may reduce recurrence and improve outcomes.