Stratifying prognosis in heart failure patients with reduced ejection fraction and atrial cardiomyopathy

BACKGROUND: Co-existence of atrial cardiomyopathy (AtCM) and heart failure with reduced ejection fraction (HFrEF) has prognostic implications. We aimed to quantify the association of a health records data biomarker, FIND-AF, with outcomes in patients with HFrEF and AtCM without atrial fibrillation (AF). METHODS: Patients with HFrEF and AtCM without AF at baseline were identified from the ECG-HF registry (2010-2016) and linked to the territory-wide Clinical Data Analysis and Reporting System. AtCM was operationalized using a pragmatic multi-domain framework based on the 2025 clinical consensus statement of the Heart Failure Association of the ESC, using electrocardiographic and echocardiographic parameters. Patients were stratified to high and low risk by sex-specific FIND-AF thresholds. The primary outcome was a composite of incident AF, ischaemic stroke, and all-cause mortality. All patients were followed until 31 December 2019. RESULTS: We included 164 patients (mean age 62.3 ± 13.0 years, 73.8% men). The primary outcome occurred in 23/32 (71.9%) high-risk versus 67/132 (50.8%) low-risk patients (OR 2.48, 95% CI 1.07-5.76; p=0.035). In the model including both FIND-AF risk group and AtCM severity, high FIND-AF risk remained associated with the composite outcome (adjusted OR 2.70, 95% CI 1.14-6.40; p=0.024). Compared with CHA2DS2-VASc, FIND-AF showed superior discrimination for the composite outcome (AUC 0.735 vs. 0.641; DeLong p=0.007) and ischaemic stroke (AUC 0.700 vs. 0.575; DeLong p=0.008). CONCLUSIONS: High FIND-AF risk is associated with adverse prognosis in a cohort of patients with HFrEF and AtCM but without baseline AF. This exploratory data requires external validation and prospective study.