Atrial cardiomyopathy: markers and outcomes

Area of Science:

• Cardiology
• Biomarkers
• Epidemiology

Background:

• Atrial cardiomyopathy (AtCM) is increasingly recognized as a significant factor contributing to atrial fibrillation (AF).
• Understanding AtCM's risk factors and its association with major cardiovascular events is crucial for clinical practice.

Purpose of the Study:

• To investigate potential markers and risk factors for AtCM.
• To assess the association of AtCM with incident AF, heart failure (HF), and stroke.
• To evaluate the additive value of AtCM markers in cardiovascular risk prediction.

Main Methods:

• Utilized UK Biobank data with cardiac MRI and ECG information from 26,467 individuals.
• Defined AtCM markers including left atrial dilation, mechanical dysfunction, P-wave prolongation, and abnormal P-wave terminal force.
• Employed logistic regression for risk factors and Cox regression/cumulative incidence models for outcomes, integrating clinical and genetic risk scores.

Main Results:

• 15.7% of individuals had at least one AtCM marker; 2.3% had two or more.
• AtCM markers were associated with significantly increased hazard ratios for AF (HR: 4.59 for ≥2 markers), HF (HR: 3.08), and stroke (HR: 3.07).
• Adding AtCM markers improved AF risk reclassification by 13.7% (NRI).

Conclusions:

• Atrial cardiomyopathy is a prevalent condition, with markers present in one in seven individuals.
• AtCM markers are independently associated with increased risks of AF, HF, and stroke.
• AtCM serves as a common pathophysiological substrate for these cardiovascular outcomes, enhancing risk prediction models.