Cardiac adipose tissue and atrial fibrillation: the perils of adiposity

Area of Science:

• Cardiology
• Biomedical Science
• Pathophysiology

Background:

• Accumulation of adipose tissue around the atria is linked to atrial fibrillation (AF) risk, persistence, and severity.
• This association is driven by complex interactions between atrial adipose tissue and the myocardium, not merely a coincidental finding.

Purpose of the Study:

• To explore the intricate relationship between epicardial adipose tissue and atrial myocardium in the context of atrial fibrillation.
• To highlight the role of inflammatory mediators and oxidative stress from adipose tissue in cardiac remodeling.
• To underscore the potential of risk factor management, particularly obesity, in treating AF.

Main Methods:

• Review of clinical and experimental evidence linking epicardial adipose tissue to atrial remodeling.
• Analysis of the mechanisms by which adipokines, inflammatory cytokines, and reactive oxidative species affect atrial myocardium.
• Consideration of fibro-fatty infiltrations and their impact on atrial function.

Main Results:

• Epicardial adipose tissue releases inflammatory mediators and oxidative species, promoting fibrotic remodeling of the atrial myocardium.
• Fibro-fatty infiltration in the subepicardium contributes to functional disorganization of the atrial myocardium.
• Obesity is associated with specific structural and functional atrial remodeling, offering therapeutic targets for AF.

Conclusions:

• The interplay between adipose tissue and atrial myocardium is a key factor in atrial fibrillation pathogenesis.
• Aggressive risk factor management, especially addressing obesity, presents a promising strategy for managing AF.
• Advancements in cardiac imaging are crucial for visualizing myocardial fat and localizing AF substrates.