Predictors of Atrial Fibrosis in an Ovine Model of Obesity

Abstract

Atrial fibrosis is recognised as the histopathological correlate of the atrial fibrillation (AF) substrate and predictive of chronicity. Methods: An ad-libitum calorie-dense diet was used to promote obesity in a cohort of 30 sheep. During dynamic weight gain, 10 were sampled at baseline, 4 months and 8 months for detailed cardiac MRI, invasive arterial and LA pressure measurements. Atrial tissue fibrosis was quantified using picrosirius red stain, inflammation was graded using H&E staining and myocardial lipid content proportioned using Oil-red-O staining. Tissue analysis was quantified by automated digital methods. Results and Conclusion: Weight progressively increased (48kg-125kg). There w..