Atrial FDG uptake and atrial fibrillation: A systematic review and meta-analysis

Atrial inflammatory and metabolic derangements have been reported in patients with atrial fibrillation (AF).

We sought to evaluate the association of ¹⁸F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) in the left and right atria and AF.

We conducted a systematic review and meta-analysis, using the PRISMA Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, of studies involving patients undergoing FDG-PET scans with reported atrial or ventricular uptake and outcomes of AF. Data were pooled and analyzed, and FDG uptake in AF and non-AF patients was compared using odds ratios (ORs).

Six studies (4 retrospective, 1 prospective, and 1 case-control) were included in the meta-analysis of studies on patients not meeting diagnostic criteria for cardiac sarcoidosis (CS): 832 patients with a mean age of 67 years, 62% male, and 53% with hypertension. AF patients demonstrated higher odds of FDG uptake in the left atrium (pooled OR 14.50, 95% confidence interval 6.78-31.02; P < .0001, I ² = 0) and right atrium (pooled OR 51.98, 95% confidence interval 22.77-118.63, P < .0001, I ² = 0). Two studies on patients met diagnostic criteria for CS: one did not report atrial uptake and the other did not demonstrate a statistically significant association between right or left atrial uptake in AF patients.

In patients undergoing FDG-PET without meeting CS diagnostic criteria, FDG uptake in the atria was strongly associated with AF, suggesting altered metabolism or inflammation in AF pathophysiology and risk assessment.