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

Abstract

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. To investigate the incidence of esophageal lesions after PVI using the second-generation CB and the role of luminal esophageal temperature (LET) measurement as a predictor of lesion formation. Thirty-two consecutive patients underwent PVI using the second-generation 28 mm CB. Target application time was 2 × 240 seconds. Ninety-two percent of the PVs were isolated after 1 cryoenergy application. Complete 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 °C) was observed. The lowest measured LET was-12 °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 °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 healing of lesions after 16 ± 14 days. 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.