Introduction: There is increasing evidence that a certain proportion of patients with cardiac sarcoidosis have atrial arrhythmias. Although 18F-fluorodeoxy-glucose (FDG) uptake in ventricular wall on positron emission tomography/computed tomography (PET/CT) is well studied, FDG uptake in atrial wall has not been elucidated in detail. The aim of this study was to evaluate the FDG uptake in atrial wall and its relationship to atrial arrhythmias in patients with cardiac sarcoidosis.
Methods: We retrospectively investigated 71 cardiac sarcoidosis patients. All patients underwent echocardiography, 24-h ambulatory Holter monitoring, and PET/CT. Serum angiotensin converting enzyme (ACE) and B-type natriuretic peptide (BNP) levels were also evaluated.
Results: Of the studied population, 27 patients (38.0%) had atrial arrhythmias, including 4 atrial tachycardias and 23 atrial fibrillations. PET-CT demonstrated positive atrial uptake in 35 patients (49.3%), of which 16 patients had left atrial, 4 patients had right atrial, and 15 patients had bilateral atrial uptake. Twenty one patients with atrial arrhythmias had atrial FDG uptake, whereas 14 patients without atrial arrhythmias had atrial FDG uptake (77.8% vs 31.8%, P = 0.001). Multivariate analysis revealed a significant association between atrial arrhythmias and age (odds ratio [OR]: 1.07; 95% confidence interval [CI]: 1.00-1.15, P = 0.049), atrial FDG uptake (OR: 8.75; 95% CI: 2.37-32.37, P = 0.001), and left atrial diameter (OR: 1.19; 95% CI: 1.03-1.37, P = 0.019). Meanwhile, gender, serum ACE and BNP levels, and other echocardiographic parameters (left ventricular ejection fraction, A/E ratio) were not associated with atrial arrhythmias.
Conclusions: Atrial FDG uptake was common in patients with cardiac sarcoidosis, and strongly associated with atrial arrhythmias.