Metabolic syndrome associates with left atrial dysfunction.

Area of Science:

• Cardiology
• Metabolic Health
• Medical Imaging

Background:

• Obesity and metabolic syndrome (MetS) are recognized risk factors for atrial fibrillation (AF).
• Limited data exist on the specific impact of ectopic fat depots and cardiometabolic risk factors on left atrial (LA) function.

Purpose of the Study:

• To investigate the effects of cardiac, hepatic, and intra-abdominal ectopic fat depots on LA function.
• To evaluate the influence of cardiometabolic risk factors on LA function in non-diabetic males.

Main Methods:

• Utilized 1.5T 1H-magnetic resonance spectroscopy for myocardial and hepatic triglyceride content.
• Employed magnetic resonance imaging (MRI) to assess LA and left ventricular function, visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and epicardial/pericardial fat.
• Assessed LA volumes using a novel three-chamber orientation MRI approach in men with and without MetS.

Main Results:

• Patients with MetS exhibited significantly lower LA ejection fraction (EF) compared to controls (44% vs. 49%, p=0.013) without LA enlargement, indicating subclinical LA dysfunction.
• LA EF showed negative correlations with waist circumference, BMI, SAT, VAT, fasting insulin, and HOMA-IR, and a positive correlation with HDL cholesterol.
• Visceral adipose tissue (VAT) emerged as the strongest predictor of reduced LA EF.

Conclusions:

• Metabolic syndrome is associated with subclinical left atrial dysfunction in men.
• Visceral obesity and insulin resistance are significant contributors to LA dysfunction in MetS.
• Further research is warranted to understand the role of atrial remodeling in AF development.