Derivation and validation of a novel score to detect heart failure with preserved ejection fraction in patients with atrial fibrillation: the Fushimi AF registry
Authors: Aono Y , Iguchi M , Ogawa H , Ikeda S , Doi K , Hamatani Y , Fujino A , An Y , Ishii M , Masunaga N , Esato M , Wada H , Hasegawa K , Abe M , Akao M 
Published: November 2020

Abstract

Background
Heart failure with preserved ejection fraction (HFpEF) is an important comorbidity of atrial fibrillation (AF). However, it is sometimes difficult to detect HFpEF among AF patients with preserved EF, since AF and HF share similar symptoms.

Purpose
The aim of this study was to identify factors associated with having HFpEF in AF patients with preserved EF, and derive a new score for HFpEF in AF patients.

Methods
The Fushimi AF Registry is a community-based prospective survey of the AF patients in Fushimi-ku, Kyoto, Japan. Follow-up data were available for 4,466 patients, and 3,083 patients had preserved EF (≥50%). Of the 3,083 patients, 444 had prior HF hospitalization at baseline and we defined these patients as HFpEF. We examined the factors associated with having HFpEF, and derived a new score for detecting HFpEF in AF patients. Thereafter, we validated this score in patients without prior HF hospitalization.

Result
The mean age of the patients with EF ≥50% was 73.6 years, and 41.3% were female. Compared with the patients without prior HF hospitalization, HFpEF patients were older, more often female, less in body weight, had more heart disease (valvular heart disease, cardiomyopathy, old myocardial infarction, and coronary artery disease), chronic kidney diseases (CKD), anemia (Hb &lt;11 g/dL), sustained AF (persistent or permanent), left atrial enlargement (&gt;45 mm), and dilation of cardio-thoracic ratio (CTR) (&gt;54%) at baseline. In multivariate analysis, heart diseases, CKD, sustained AF, dilatation of CTR, left atrial enlargement, and anemia were significantly associated with HFpEF (Table 1). We derived a new score to diagnose HFpEF in AF patients (2 points for heart diseases, 1 point for CKD, sustained AF, dilatation of CTR, left atrial enlargement, and anemia; range 0 to 7 points). In a receiver-operating characteristic curve, optimal cut-off point for detecting HFpEF was 3 (Figure 1). We validated this score in patients without prior hospitalization for HF (n=2,639). Of these, 298 patients had HF symptoms of NYHA 2–4 (Symptomatic-HF), and 2,341 patients had neither prior HF hospitalization nor HF symptoms (No-HF). Notably, 207 patients (69.5%) in symptomatic-HF group and 748 patients (32.0%) in No-HF group were classified into HFpEF based on this new score. Furthermore, patients diagnosed as HFpEF by this score had higher incidence of new hospitalization for HF during the follow-up in both symptomatic-HF group and No-HF group. (Figure 2).

Conclusion
We derived a new score to diagnose HFpEF in AF patients based on the presence of prior HF hospitalization (2 points for heart diseases, 1 point for CKD, sustained AF, dilatation of CTR, left atrial enlargement, and anemia). In patients without prior HF hospitalization, sizable number of patients had high HFpEF score (≥3), and those patients showed higher incidence of new HF hospitalization.

Funding Acknowledgement
Type of funding source: None