Pulmonary vein conduction is the major finding in patients with atrial tachyarrhythmias after intraoperative maze ablation.

INTRODUCTION: Electrophysiological (EP) data from patients with recurrent atrial tachyarrhythmias (ATa) after intraoperative maze ablation are limited. Furthermore, the clinical course after accomplishing pulmonary vein (PV) isolation using the double lasso technique (DLT) is unknown.

METHODS AND RESULTS: EP study and catheter ablation (CA) was guided by a three-dimensional electroanatomic mapping system (3-D EA, CARTO, Biosense-Webster) combined with simultaneous ipsilateral PV mapping using the DLT. Defined endpoints were: (1) identification of conduction gaps within the ipsilateral PVs, (2) elimination of all PV spikes, and (3) ablation of clinical ATas. CA was performed in eight patients (four females, 62 +/- 5 years, LA: 50 +/- 6 mm) with drug refractory ATa (9.1 +/- 6.3 years) despite non-"cut and sew" maze operation. Electrical PV conduction was demonstrated in the majority of patients (7/8). All endpoints were achieved. Repeat ablations were required in three patients. Second ablation was due to typical atrial flutter (n = 1) and atrial fibrillation (n = 2). One patient required three ablations due to a left atrial macroreentrant tachycardia. During a mean follow-up of 15.5 +/- 4.8 months, 7/8 patients were free of ATa recurrences.

CONCLUSION: Incomplete lesions after non-"cut and sew" maze operation are associated with PV conduction and recurrence of ATas. Electrical isolation of ipsilateral PVs and completion of linear lesions guided by 3-D EA mapping is feasible and successful in maintaining sinus rhythm during mid term follow-up. Completeness of linear lesions using EP endpoints should be confirmed during the initial surgical procedure to minimize ATa recurrences.