Impact of pre-ablation cardiorespiratory fitness and echocardiographic parameters on atrial fibrillation ablation outcomes.

Background: Studies have shown a correlation between greater cardiorespiratory fitness (CRF) and lower risk of incident and recurrent atrial fibrillation (AF). Transthoracic echocardiographic (TTE) parameters correlate to CRF and risk of AF. However, there is scarce data regarding the interplay of CRF, echocardiographic parameters, and AF ablation outcomes. Our study sought to investigate how CRF and echocardiographic parameters impact AF ablation outcomes.

Methods: We evaluated the Mayo Clinic Cardiorespiratory Exercise database from January 1, 2013, through December 31, 2017, to include all patients who underwent cardiopulmonary exercise testing and an AF ablation in temporal proximity.

Results: A total of 205 patients (mean age 61.2 years, 74% male) were included for analysis. Fitness was calculated with peak VO2 when available and exercise time when VO2 was not available. Lower baseline fitness correlated to larger left atrial volumes, lower medial mitral e' values, and higher E/e' ratios. Lower baseline fitness correlated to higher risk of AF recurrence post-ablation in a simple model, but lost significance when multiple variables were accounted for. Lower baseline fitness also correlated to a higher AF burden post-ablation at one year.

Conclusions: Lower baseline CRF likely correlates to more malignant and difficult to treat AF. Lower fitness also correlated to larger left atria and TTE parameters suggestive of diastolic dysfunction.