Luminal esophageal temperature predicts esophageal lesions after second-generation cryoballoon pulmonary vein isolation

BACKGROUND The novel second-generation cryoballoon (CB) facilitates pulmonary vein isolation (PVI) by improved surface cooling. The impact of this redesign on collateral damage is unknown. OBJECTIVE To investigate the incidence of esophageal lesions after PVI using the second-generation CB and the rote of lumina l esophageal temperature (lET) measurement as a predictor of lesion formation. METHODS Thirty-two consecutive patients underwent PVI using the second-generation 28 mm CB. Target application time was 2 x 240 seconds. Ninety-two percent of the PVs were isolated after 1 cryoenergy application. Compete PVI was achieved in all patients. lET with 3 thermocouples was continuously measured during cryoenergy application. Freezing was interrupted only if weakening/loss of phrenic nerve function or low lET (<5 degrees C) was observed. RESULTS The lowest measured lET was 12 degrees C (despite cryoapplication interruption). Postprocedural gastroesophagoscopy was performed after 1-3 days in all patients and showed lesions in 6 of 32 (19%) patients. A minimum lET of <= 12 degrees C predicted esophageal lesions with 100% sensitivity and 92% specificity (area under the receiver-operator characteristic curve 0.97; 95% CI 0.93-1.02; P =.001). Persistent phrenic nerve palsy occurred in 2 (6%) patients during ablation at the right inferior pulmonary vein. Repeat gastroesophagoscopy confirmed heating of lesions after 16 +/- 14 days. CONCLUSIONS Second-generation 28 mm CB PVI is associated with significant esophageal cooling, resulting in lesion formation in 19% of the patients. lET measurement accurately predicts lesion formation and may enhance the safety of the novel device.