Abstract 17695: Diastolic Dysfunction May Underlie Sex Differences in Outcome Following Catheter Ablation for Atrial Fibrillation in Patients with Preserved Ejection Fraction
Introduction: Reduced efficacy of radiofrequency catheter ablation (RFA) for atrial fibrillation (AF) in females has been reported. Diastolic dysfunction (DD) resulting in elevated left atrial (LA) pressure (LAP) may promote LA remodeling and create a substrate for AF, whereas RFA primarily targets AF triggers.
Hypothesis: We hypothesized that among patients with normal ejection fraction (EF), females undergoing RFA for symptomatic AF have more DD, higher LAP and poorer outcomes. As DD predisposes to heart failure (HF) independent of AF, we also determined if sex predicted quality of life (QOL) independent of ablative efficacy.
Methods: 707 patients with preserved EF (≥0.5) undergoing first time RFA for AF (age 60±11 years, 26% female) underwent echocardiography and invasive LAP measurement (transseptal approach) prior to RFA. QOL and AF-related symptoms (SF-36 and MAFSI) and 1-year outcomes were assessed.
Results: Female AF patients were older (63±10 vs. 59±10 years; p<0.0001) but had a similar prior duration of AF. Females had less CAD (7% vs. 18%, p=0.0004) but otherwise comparable comorbidity to males. Despite more frequent paroxysmal AF (49% vs. 38%, p=0.01), females had more AF-related symptoms (p<0.0001) and poorer baseline QOL (p=0.02). Females had higher EF (62±7 vs. 58±10%, p<0.0001) but worse diastolic function (E/e’ 11.9±5.7 vs. 9.9±4.9, p<0.0001; and PASP 32.3±8.2 vs. 29.4±6.6 mmHg, p<0.0001). Indexed LA volume and LV geometry were similar between sexes, but peak systolic LAP was higher in females (20.7±6.7 vs. 19.0±6.0mmHg, p=0.0009) consistent with reduced LA compliance. AF recurrence was higher in females (27% vs. 19%, p=0.02) even after adjusting for age (Female sex OR 1.55, 95%CI 1.03-2.33, p=0.04). QOL at 1 year remained poorer in females (p=0.05), largely independent of AF recurrence (sex stratified analysis).
Conclusion: Females with preserved EF and symptomatic AF undergoing RFA have worse diastolic function compared to males which may contribute to their increased AF recurrence and poorer QOL, despite comparable comorbidity and prior duration of AF in this cohort. Symptomatic AF in patients with DD may herald future HF, particularly in females.
- © 2012 by American Heart Association, Inc.