Abstract 9856: Left Atrial Passive Emptying Function Determined by Cardiac Magnetic Resonance Predicts Atrial Fibrillation Recurrence After Pulmonary Vein Isolation
Background: While pulmonary vein isolation (PVI) has become a mainstream therapy for selected patients with AF, late AF recurrence is common and its risk factors remain poorly defined. The purpose of our study was to test the hypothesis that reduced left atrial passive emptying function (LAPEF) has a strong association with late recurrent AF after PVI.
Methods: 346 patients with AF referred for CMR pulmonary vein mapping prior to PVI from 9/2005-6/2011 were included. Left atrial volumes (LAV) were determined by the biplane area-length method. LA maximum volumes (VOLmax) and volumes before atrial contraction (VOLbac) were measured, and LAPEF was calculated as (VOLmax - VOLbac)/VOLmax x 100. The primary outcome was late recurrent AF (≥ 3 months after PVI). Late AF-free survival curves stratified by LAPEF quintiles were plotted using the Kaplan-Meier method. Cox proportional hazards assessed the prognostic association of LAPEF with recurrent AF, adjusting for known markers of AF recurrence (BSA, VOLmax, hypertension, non-paroxysmal AF, diabetes, heart failure, ≥1 PVI procedure, sleep apnea).
Results: Over a median follow-up of 27 months, 124 patients (35.8%) experienced recurrent AF. Patients with recurrence were more likely to have non-paroxysmal AF (75.8% vs. 51.4%, P<0.01), larger mean LA volumes (60.2 ml/m2 vs. 52.8 ml/m2, P<0.01), and lower mean LAPEF (19.1 vs. 26.0, P<0.01). Patients in the lowest quintile of LAPEF (worst function) were at the highest risk of developing recurrent AF (Figure); at two years, the recurrence rate was 60.5% in the lowest quintile, compared to 17.3% in the highest quintile. After adjusting for historic markers of recurrent AF, patients with low LAPEF remained significantly more likely to recur (HR lowest vs. highest = 3.92, 95% CI 2.01-7.65).
Conclusions: We found a strong association between LAPEF and recurrent AF after PVI that persisted after multivariable adjustment. LAPEF may be used to risk stratify PVI candidates for late recurrence.
- © 2013 by American Heart Association, Inc.