Atrial fibrillation from the pathologist's perspective

Area of Science:

• Cardiology
• Cardiac Electrophysiology
• Molecular Cardiology

Background:

• Atrial fibrillation (AF) is a common arrhythmia linked to high morbidity and mortality.
• Historically viewed as functional, AF is now recognized to have structural underpinnings.
• Pulmonary veins and surrounding atrial myocardium are key sites for AF initiation and maintenance.

Purpose of the Study:

• To review the current understanding of the structural and genetic bases of atrial fibrillation.
• To explore the classification, pathogenesis, and clinical implications of AF-related structural remodeling.
• To elucidate the pathogenetic vicious circle involving AF and myocardial structural changes.

Main Methods:

• Review of recent mapping and imaging techniques.
• Morphological analysis of myocardial tissue in AF patients.
• Synthesis of current literature on AF pathogenesis and genetics.

Main Results:

• Identification of specific atrial regions (e.g., pulmonary veins) crucial for AF.
• Demonstration of significant structural remodeling in these myocardial sites.
• Understanding of how AF induces and is sustained by structural changes, forming a vicious cycle.

Conclusions:

• Structural remodeling is integral to AF pathogenesis, not just a consequence.
• Genetic factors likely contribute to individual susceptibility and disease progression.
• This knowledge advances understanding of AF natural history and informs treatment strategies.