Atrial electrophysiology is altered by acute hypercapnia but not hypoxemia: Implications for promotion of atrial fibrillation in pulmonary disease and sleep apnea

Abstract

Background: Chronic pulmonary disease and sleep apnea have been associated with the development of atrial fibrillation (AF). Objective: The purpose of this study was to characterize the atrial electrical changes that occur with hypercapnia and hypoxemia and to determine their role in AF development. Methods: Seventeen sheep (6 control, 5 hypercapnia, 6 hypoxemia) underwent open chest electrophysiologic evaluation under autonomic blockade. A 64-electrode endocardial basket catheter was positioned in the right atrium, and 2 × 128 electrode epicardial plaques were sutured to the right atrial and left atrial appendages to determine atrial refractoriness (effective refractory period [ERP]) at 9 s..