title: Atrial fibrillation is associated with hematopoietic tissue activation and arterial inflammation.
abstract: Inflammation is associated with the development of atrial fibrillation (AF). Activity in hematopoietic tissues, which produce inflammatory leukocytes, is closely related to systemic inflammation, arterial inflammation and cardiovascular events, but its relationship to AF is unknown. Using 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging, we examined the relationships between AF, splenic metabolic activity and vascular inflammation. We conducted a cross sectional study of 70 participants: 35 with AF, who were matched (by age, sex and history of active cancer) to 35 controls without AF. Splenic metabolic activity and vascular aortic inflammation were measured by the mean FDG maximum standard uptake values (SUV Max) by PET. We examined (1) the association between AF and splenic activity, and (2) AF and aortic inflammation. The mean age of the population was 68.13 (standard deviation (SD) 8.98) years and 46 (65 %) participants were male. Splenic activity was higher in AF participants [2.31 (SD 0.45) vs. 2.07 (SD 0.37), p = 0.024], and remained significant after adjusting for demographic and clinical covariates. Aortic inflammation was also higher in AF participants [2.22 (SD 0.44) vs. 1.91 (SD 0.44), p = 0.004], and remained significant on multivariable analysis. Aortic inflammation and splenic activity were highly correlated (Pearson R = 0.61, p < 0.001). Atrial fibrillation is associated with higher hematopoietic tissue activation and arterial inflammation. Further studies are needed to clarify the mechanisms by which this cardio-splenic axis is implicated in AF.
authors.affiliation: Cardiac MR PET CT Program, Division of Cardiac Imaging, Massachusetts General Hospital and Harvard Medical School, Suite 400-165 Cambridge St, Boston, MA, 02114, USA.|McMaster University, Hamilton, ON, Canada.
authors.forename: Philip
authors.initials: P
authors.lastname: Joseph
authors.affiliation: Cardiac MR PET CT Program, Division of Cardiac Imaging, Massachusetts General Hospital and Harvard Medical School, Suite 400-165 Cambridge St, Boston, MA, 02114, USA.
authors.forename: Amorina
authors.initials: A
authors.lastname: Ishai
authors.affiliation: Cardiac MR PET CT Program, Division of Cardiac Imaging, Massachusetts General Hospital and Harvard Medical School, Suite 400-165 Cambridge St, Boston, MA, 02114, USA.
authors.forename: Megan
authors.initials: M
authors.lastname: MacNabb
authors.affiliation: Cardiac MR PET CT Program, Division of Cardiac Imaging, Massachusetts General Hospital and Harvard Medical School, Suite 400-165 Cambridge St, Boston, MA, 02114, USA.
authors.forename: Amr
authors.initials: A
authors.lastname: Abdelbaky
authors.affiliation: Cardiac MR PET CT Program, Division of Cardiac Imaging, Massachusetts General Hospital and Harvard Medical School, Suite 400-165 Cambridge St, Boston, MA, 02114, USA.
authors.forename: Zachary R
authors.initials: ZR
authors.lastname: Lavender
authors.affiliation: Cardiac MR PET CT Program, Division of Cardiac Imaging, Massachusetts General Hospital and Harvard Medical School, Suite 400-165 Cambridge St, Boston, MA, 02114, USA.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Ruskin
authors.affiliation: Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: Matthias
authors.initials: M
authors.lastname: Nahrendorf
authors.affiliation: Cardiac MR PET CT Program, Division of Cardiac Imaging, Massachusetts General Hospital and Harvard Medical School, Suite 400-165 Cambridge St, Boston, MA, 02114, USA. atawakol@partners.org.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Tawakol
mesh_terms: D000368:Aged; D001025:Aortitis / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D001027:Aortography; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D001853:Bone Marrow / Q000000981:diagnostic imaging / Q000503:physiopathology*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000008:administration & dosage; D006410:Hematopoiesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D011379:Prognosis; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D012307:Risk Factors; D013154:Spleen / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Atrial fibrillation; Hematopoietic activation; Positron emission tomography