Abstract:

Background: Atrial myopathy refers to structural and functional cardiac abnormalities associated with atrial fibrillation (AF) and stroke, but appropriate diagnostic criteria are lacking. We aimed to assess prevalence, clinical correlates, and overlap between potential atrial myopathy markers.

Methods: The population-based Swedish CArdioPulmonary bioImage Study prospectively included 6,013 AF-free subjects with 24h-electrocardiograms (24hECGs). Resting ECGs measuring P-wave indeces were collected at one screening site (n=1,201 subjects), and a random sample (n=385) had echocardiographic left atrial volume index (LAVi). Atrial myopathy markers were defined as ≥500 premature atrial complexes (PACs)/24h, LAVi>34ml/m2, P-wave duration>120ms, or P-wave terminal force in V1>4000ms*s. Clinical correlates included age, sex, BMI, height, smoking, physical activity, coronary artery disease (CAD), diabetes, systolic blood pressure (SBP), antihypertensive medication, and low education.

Results: Atrial myopathy was common; 42% of the population with all diagnostic modalities available had>1 atrial myopathy marker, but only 9% had 2 and 0.3% had>3. Only P-wave duration and LAVi were correlated (rho 0.10, p=0.04). Clinical correlates of PACs, P-wave indices, and LAVi differed; current smoking (34% increase, p<0.001), SBP (4%/mmHg increase, p=0.01) diabetes (35% increase, p=0.001) and CAD (71% increase, p=0.003) were associated with PACs, physical activity>2 hours/week was associated with increased LAVi (Beta-coefficient 3.1 p<0.0001) and BMI was associated with P-wave duration (Beta-coefficient 0.4/kg/m2, p<0.0001).

Conclusions: In the general population, indirect markers of atrial myopathy are common but only weakly correlated, and their risk factor patterns are different. More studies are needed to accurately identify individuals with atrial myopathy with diagnostic methods.

Editor-in-Chief

Kalyanam Shivkumar, MD, PhD, FACC 

CME Editor
Kenneth A. Ellenbogen, MD, FACC

Author
Mahmoud Houmsse, MD, FACC 

Important Dates
Date of Release: November 27, 2023
Term of Approval/Date of CME/MOC Expiration: November 26, 2024