Atrial fibrillation is an independent risk factor for heart failure progression and pump failure mortality in HFpEF:: a propensity score matched analysis of the TOPCAT Americas study

Abstract Funding Acknowledgements Type of funding sources: None. Background Atrial fibrillation (AF) is associated with excess mortality and cardiovascular (CV) hospitalizations in HF patients (pts) with preserved systolic function (pEF) but the contributing factors to these outcomes are not known.. Purpose To analyze the independent impact of AF on clinical outcomes of HFpEF pts in the TOPCAT AMERICAS study using propensity score matched (PSM) cohorts to account for confounding by other comorbidities. Methods Study cohorts were PSM matched for 20 clinical, demographic & ECG variables. 3 matched cohorts based on baseline rhythm status at study entry were compared viz. subjects in sinus rhythm (SR), subjects in AF on baseline ECG & subjects with Any AF event by history or ECG. We analyzed CV mortality, adjudicated modes of death & morbidity during a mean follow up period of 2.9 yrs. Results 418 subjects in SR (SR cohort) were PSM with 418 subjects in AF on baseline ECG (AF on ECG cohort) & 418 pts with any AF event by history or ECG (Any AF cohort) at study entry. Any AF increased the risk of CV death (D), pump failure death (PFD), CV and HF hospitalization (H) and HF progression. AF on ECG increased risk of CVD, CVH, HFH and PFD (Tables). Neither AF cohort increased risk of sudden death (SD) {Figure}. Conclusion 1. AF is an independent risk factor for worsening CV outcomes in HFpEF. 2. This increased risk is due to a selective increase in symptomatic HF progression from early to advanced HF, HFH and PFD in advanced HF rather than SD. 3. Loss of AV synchrony & rate control in AF can independently impact HF progression in HFpEF with consequent HFH and PFD. Restoration of SR may offer benefits for CV outcomes in HFpEF & warrants evaluation.