Esophageal Acid Levels after Pulmonary Vein Isolation for Atrial Fibrillation

BACKGROUND: Pulmonary vein antrum isolation (PVAI) is a potentially curative, nonpharmacologic treatment of atrial fibrillation (AF). Several procedural complications have been described, including esophageal wall lesions ranging from erythema and esophagitis, necrosis and ulcer, to atrio-esophageal fistula. We prospectively studied changes in esophageal acid levels before and after PVAI. METHODS: We performed 24-hour pH-metry before and 1.3 +/- 1.6 days after PVAI, in 25 patients (mean age = 62 +/- 12 years, 17 men) with symptomatic AF. A 2-mm transnasal probe was inserted into the inferior part of the esophagus and into the stomach to measure pH levels at fixed intervals. DeMeester scores, indicating acidic gastro-esophageal reflux, were calculated. RESULTS: The mean number of reflux episodes increased from 89 +/- 80 before to 107 +/- 94 after PVAI. The mean percentage of time with esophageal pH < 4 was shorter after (108 +/- 193 minutes) than before PVAI (159 +/- 245 minutes). The mean DeMeester score decreased from 49 +/- 68 before to 31 +/- 41 after PVAI (P < 0.05). We observed erythema or esophagitis in five patients, necrosis or ulcer in seven, and atrio-esophageal fistula in no patient. CONCLUSIONS: Our hypothesis of increased acid levels caused by stimulation of the right vagal nerve during isolation of the right upper pulmonary vein was not verified.