Abstract 12069: Impact of Atrial Fibrillation on Outcomes in Patients With Heart Failure With Reduced, Mildly Reduced and Preserved Ejection Fraction. A Systematic Review and Meta-Analysis of Published Studies

Background: Atrial fibrillation (AF) is highly prevalent in patients with heart failure (HF), however the difference in outcomes between the HF sub-types is not well known. Contemporary classification of HF categorizes it into HF with reduced ejection fraction (HFrEF), HF with mildly reduced ejection fraction (HFmrEF), and HF with preserved ejection fraction (HFpEF). With the new designation of HFmrEF, there have been studies researching the risk profile of AF in the three HF categories, however there is not yet a unifying statement on these data.

Aim: Systematic review and meta-analysis aimed to determine if there are any significant differences in AF-associated all-cause mortality (primary endpoint), heart failure hospitalizations, cardiovascular mortality, and stroke (secondary endpoints) between HFrEF, HFmrEF, and HFpEF.

Methods: A systematic search of PubMed, EMBASE, and Cochrane Library databases until February 28 ^th , 2023, identified studies reporting clinical outcomes linked to AF by HF category status. Data were combined using D+L random effects model.

Results: The review included 21 studies comprising 238,107 patients. Pooled AF prevalence: 32% in HFrEF, 38% in HFmrEF, and 43% in HFpEF. AF was associated with a higher risk of all-cause mortality in HFmrEF and HFpEF only (Figure for pooled hazard ratio (HR) and 95% CI). AF associated with a higher risk of HF hospitalizations, in the total population (HR=1.29, 95% CI=1.14-1.46), HFmrEF (HR=1.64, 95% CI=1.20-2.24), and HFpEF (HR=1.46, 95% CI=1.17-1.83), but not HFrEF (HR=1.01, 95% CI=0.87-1.18). AF was only associated with cardiovascular mortality in the HFpEF subcategory but was associated with stroke in all three HF subtypes.

Conclusion: AF was associated with a higher risk of all-cause mortality and heart failure hospitalization in HFmrEF and HFpEF only. As treatment guidelines for AF in HFmrEF are limited, the benefit of treatments to control AF in this subgroup should be further investigated.