PO-02-222 CARDIORESPIRATORY FITNESS AND COMPREHENSIVE ATRIAL REMODELLING IN PATIENTS WITH SYMPTOMATIC ATRIAL FIBRILLATION

Abstract

Cardiorespiratory fitness (CRF) are important independent prognostic markers in AF. The influence of CRF on atrial (LA) electrical and functional remodelling in AF is unknown. To use cardiopulmonary exercise testing (CPET) to assess the link between CRF, PA and atrial remodelling assessed both invasively and non-invasively. Consecutive patients with symptomatic paroxysmal or persistent AF undergoing AF ablation were recruited. CRF was assessed objectively by measuring peak oxygen consumption (VO2PEAK) during CPET. Invasive assessment of atrial remodelling involved assessment of LA and RA electrical function using high-density electroanatomical maps and hemodynamic assessment of LA and RA pressures. Non-invasive assessment involved 2D transthoracic echocardiography at rest and during exercise. The association between VO2PEAK and atrial parameters were determined using multivariable linear regression models adjusted for age and sex. In total, 120 participants were recruited. Mean age was 63.2±11.2 and 74.5% of the cohort was male. In adjusted analyses, we observed a significant positive relationship between VO2PEAK and bipolar LA (p=0.049) and RA voltages (p=0.046). In addition, there was an inverse relationship between VO2PEAK and mean LAP (p<0.001) and mean RAP (p=0.013). On non-invasive testing, VO2PEAK was positively associated with left atrial emptying fraction (LAEF) (p=0.001) and reservoir strain (p<0.001) at rest. During exercise, VO2PEAK remained associated with LAEF (p<0.001) and LA reservoir strain (p=0.007). In patients with symptomatic AF, poor CRF is independently associated with extensive atrial remodelling involving LA and RA electrical remodelling, impaired LA haemodynamics, and LA mechanical dysfunction.