Background: Thermal esophageal injury is a rare but devastating complication of pulmonary vein isolation using radiofrequency energy or cryoablation (CRYO) and also radiofrequency ablation of posterior wall (PW). Risk of esophageal injury with PW and roof CRYO is unknown. Since PW and roof CRYO has recently been advocated, we studied minimum esophageal temperature (MET) to assess safety of PW and roof CRYO.

Purpose: To assess safety of PW and roof CRYO for atrial fibrillation.

Methods: CRYO was performed in 16 patients (mean age: 64 ± 9 years; mean left atrial volume: 59 ± 24 mL/m2 ; male sex: 12) with atrial fibrillation (8 paroxysmal, 8 persistent). Following pulmonary vein isolation, CRYO balloon was dragged across the roof and PW with lesions delivered at half-balloon-width intervals. CRYO balloon and esophagus were precisely localized to 1 mm accuracy with Navik 3D mapping system (APN Health, LLC, Waukesha, WI). Lesions were maintained for 3 minutes unless a MET of

Results: Lesions were distributed as follows: roof (n=81), PW (n=34), and pulmonary veins (right superior [RSPV, n=19], right inferior [RIPV, n=21], left superior [LSPV, n=19], and left inferior [LIPV, n=17]). Occurrence of MET of

Conclusion: Significant esophageal cooling with CRYO is less common at the roof and PW than in inferior pulmonary veins, and the overall incidence is low. CRYO of PW and roof may be safer than CRYO of pulmonary veins.