Sex differences in atrial potential morphology.

Area of Science:

• Cardiology
• Electrophysiology
• Cardiac Anatomy

Background:

• Conduction disorders are crucial in atrial fibrillation (AF) initiation and perpetuation.
• Unipolar potential morphology changes, like EGM fractionation, indicate asynchronous cardiomyocyte activation due to fibrotic barriers.
• Sex differences in unipolar potential morphology remain largely unexplored.

Purpose of the Study:

• To investigate potential sex differences in atrial unipolar potential morphology during sinus rhythm (SR).
• To compare electrical conduction characteristics between male and female patients.

Main Methods:

• Propensity score matching identified 62 male and female patients undergoing cardiac surgery.
• High-resolution mapping of the right atrium (RA), left atrium (LA), and pulmonary vein area (PVA), including Bachmann's bundle (BB).
• Unipolar potentials were classified (SPs, SDPs, LDPs, FPs, FD), and conduction block lines were assessed.

Main Results:

• Females showed higher proportions of short double potentials (SDPs), long double potentials (LDPs), and fractionated potentials (FPs) in the RA and PVA.
• Females had longer fraction durations (FDs) and lower single potential (SP) voltages in the RA.
• Females exhibited more conduction blocks (CB) in the RA and PVA.

Conclusions:

• Female patients demonstrated a lower proportion of single unipolar potentials, indicating less smooth conduction in the RA and PVA.
• Increased conduction blocks in females suggest sex-specific electrical remodeling.
• Findings highlight potential sex-based variations in atrial electrical properties relevant to AF.