Association of Atrial Fibrillation Progression With Left Atrial Functional Reserve and Its Reversibility

Background Atrial fibrillation (AF) progression is closely related to heart failure occurrence, and catheter ablation carries a beneficial effect for heart failure prevention. Recently, particular attention has been given to left atrial (LA) function and functional reserve in the pathogenesis linking AF and heart failure, although its significance and reversibility is not well studied. Methods and Results We prospectively investigated 164 patients with AF with normal left ventricular systolic function and free from heart failure who underwent first catheter ablation and pre‐/postprocedural echocardiography. Conventional and speckle‐tracking echocardiography were performed at rest and during passive leg lifting to assess LA size, LA reservoir strain (LARS), and functional reserve calculated as passive leg lifting‐LARS – rest‐LARS. Patients were categorized into 3 AF subtypes: paroxysmal AF (N=95), persistent AF (PeAF; N=50), and long‐standing persistent AF (LS‐PeAF; N=19). The PeAF and LS‐PeAF groups had larger LA size and reduced LARS compared with the paroxysmal AF group (all P