A MAJOR UK Biobank study has found that atrial cardiomyopathy, a condition marked by electrical and structural changes in the atria, is strongly linked with higher risks of atrial fibrillation, stroke, and heart failure.
Understanding Atrial Cardiomyopathy and Its Growing Significance
Atrial cardiomyopathy (AtCM) is gaining recognition as a critical underlying cause of atrial fibrillation (AF). Once considered a secondary finding, it is now viewed as a key player in cardiac remodelling and disease progression. This new study examined more than 26,000 participants to identify markers and outcomes associated with AtCM, aiming to determine how it contributes to major cardiovascular events.
How Atrial Cardiomyopathy Predicts Major Cardiac Events
In this large-scale analysis of 26,467 individuals from the UK Biobank, 15.7% had at least one marker and 2.3% had two or more markers of atrial cardiomyopathy. Risk factors such as age, hypertension, and coronary artery disease were strongly associated with AtCM. Having one marker conferred a hazard ratio (HR) for AF of 1.88 (95% CI 1.54–2.31; P < .001), while those with two or more markers had a dramatically higher HR of 4.59 (95% CI 3.52–5.99; P < .001). The study also found increased risk for heart failure (HR 3.08, 95% CI 2.03–4.66; P < .001) and stroke (HR 3.07, 95% CI 1.78–5.28; P < .001). Integration of AtCM markers improved risk prediction for AF by a net reclassification improvement (NRI) of 13.7% (95% CI 9.2%–18.3%).
Clinical Implications and Future Outlook
The researchers found that AtCM may represent a shared substrate for AF, heart failure (HF), and stroke, suggesting that early detection could be vital in preventing serious complications. Importantly, only those with multiple markers faced the highest risks, indicating that risk stratification could guide preventive care. Reducing modifiable factors such as hypertension, coronary artery disease, and excessive alcohol intake may help slow disease progression. Further research, including the ongoing RACE X trial, aims to determine whether interventions such as catheter ablation can halt or reverse AtCM. For clinicians, these findings reinforce the importance of early identification and comprehensive management of AtCM in cardiovascular care.
Reference
Vad OB et al. Atrial cardiomyopathy: markers and outcomes. European Heart Journal. 2025:ehaf793.
