Applicability and prognostic value of new proposed criteria for atrial cardiomyopathy in patients with heart failure

Background Atrial function plays a crucial role in patients with heart failure (HF). Recently, a criteria of atrial cardiomyopathy (AtCM) have been proposed based on both electrical and mechanical atrial dysfunction. However, it is unclear whether AtCM defined by the proposed criteria can stratify the risk of adverse events in patients with HF. Purpose We sought to investigate the association between AtCM and clinical outcomes. Methods Between January 2020 and June 2025, 2,046 symptomatic patients with chronic HF enrolled in a prospective multicenter registry (29 sites) were analysed. Electrical atrial dysfunction (EAD) was defined by the presence of any P-wave abnormality on a standard 12-lead electrocardiogram, including interatrial block and advanced interatrial block. Mechanical atrial dysfunction (MAD) was defined as impaired left atrial reservoir strain (LArS <23%) and or increased left atrial volume index (LAVI >40 mL/m², or >48 mL/m² in females aged >65 years). AtCM was diagnosed when both EAD and MAD were present. The primary outcome was a composite of all-cause death and hospitalisation for worsening HF. Results Among the 2,046 patients, 1,341 (65.5%) were classified as having AtCM. Patients with AtCM were older, more frequently male, and more often had advanced HF and reduced left ventricular ejection fraction compared with those without AtCM. During a median follow-up of 728 days (interquartile range, 519–1115 days), the primary outcome occurred in 427 patients (20.9%). Kaplan–Meier analysis showed a significantly higher cumulative incidence of the primary outcome in patients with AtCM than in those without AtCM (P <0.001) (Figure 1A). When patients were stratified according to EAD and MAD status, those with both abnormalities had the highest event rates (Figure 1B). In multivariable Cox regression analyses, AtCM remained independently associated with the primary outcome after adjustment for significant prognostic covariates (hazard ratio 1.43, 95% confidence interval, 1.11–1.84) and after additional adjustment for N-terminal pro-B-type natriuretic peptide and the MAGGIC risk score (hazard ratio 1.51, 95% confidence interval 1.17–1.94). Increasing severity of P-wave abnormalities was associated with a stepwise increase in event rates (Figure 2A), and MAD defined by either LArS or LAVI showed comparable prognostic value (Figure 2B and C). The association between AtCM and adverse outcomes was consistent between HF with reduced ejection fraction (HFrEF) and non-HFrEF (P for interaction = 0.47) and between males and females (P for interaction = 0.050), with no significant interactions observed. Conclusions AtCM defined by the proposed criteria identified patients with HF at increased risk of adverse events. Combined electrical and mechanical atrial dysfunction characterised a subgroup with markedly elevated risk, underscoring the clinical relevance of integrating both domains when diagnosing AtCM.