Impact of atrial fibrillation on cerebro-cardiovascular outcome of heart failure with mildly-reduced ejection fraction

Aims: Atrial fibrillation (AF) and heart failure (HF) often co-exist and are closely intertwined. The impact of AF on the outcome of patients with heart failure with mildly-reduced ejection fraction (HFmrEF) is not fully clear. This study aimed to investigate the impact of AF on the outcomes of hospitalized HFmrEF patients.

Methods and results: The study included 1691 consecutive patients with HFmrEF (mean 68.2 years, 64.8% male) including 296 AF patients. Patients completed 1 year and mean of 33 month clinical follow-up after discharge by telephone interview, clinical visit, or community visit. The primary endpoint was cerebro-cardiovascular events (CCE, composite of HF rehospitalization, stroke, or cardiovascular death). After propensity score matching, 296 patients were included into the AF group (mean 71.5 years) and 592 patients into the non-AF group (mean 70.6 years). After propensity score matching, CCE at 1 year (59.1% vs. 48.5%, P = 0.003) and at a mean of 33 month (77.0% vs. 70.6%, P = 0.043). AF was independently associated with increased CCE within 1 year (HR = 1.31, 95% CI 1.07 to 1.61, P = 0.010) and at 33 months (HR = 1.20, 95% CI 1.00 to 1.43, P = 0.050) post-discharge after adjusted for other clinical confounders including discharge heart rate, NT-proBNP, haemoglobin, and uric acid.

Conclusions: AF is independently associated with an increased risk of CCE in HFmrEF patients within 1 year and at a mean of 33 months after discharge.