Risk assessment of patients with clinical manifestations of cardiac sarcoidosis with positron emission tomography and magnetic resonance imaging.
BACKGROUND
Prior studies have shown that late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) and fluorodeoxyglucose (FDG) positron emission tomography (PET) confer incremental risk assessment in patients with cardiac sarcoidosis (CS). However, the incremental prognostic value of the combined use of LGE and FDG compared to either test alone has not been investigated, and this is the aim of the present study.


METHODS
Retrospective observational study of 56 symptomatic patients with high clinical suspicion for CS who underwent LGE-CMR and FDG-PET and were followed for the occurrence of death and/or malignant ventricular arrhythmias (VA).


RESULTS
The combination of PET and CMR yielded the following groups: 1) LGE-negative/normal-PET (n=20), 2) LGE-positive/abnormal-FDG (n=20), and 3) LGE-positive/normal FDG (n=16). After a median follow-up of 2.6years (IQR 1.2-4.1), 16 patients had events (7 deaths, 10 VA). All, but 1, events occurred in patients with LGE. LGE-positive/abnormal-FDG (7 events, HR 10.1 [95% CI 1.2-84]; P=0.03) and LGE-positive/normal-FDG (8 events, HR 13.3 [1.7-107]; P=0.015) patients had comparable risk of events compared to the reference LGE-negative/normal-PET group. In adjusted Cox-regression analysis, presence of LGE (HR 18.1 [1.8-178]; P=0.013) was the only independent predictor of events.


CONCLUSIONS
CS patients with LGE alone or in association with FDG were at similar risk of future events, which suggests that outcomes may be driven by the presence of LGE (myocardial fibrosis) and not FDG (inflammation).
Division of Cardiology, University of Washington School of Medicine, Seattle, WA, United States; Noninvasive Cardiovascular Imaging Program, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States. Electronic address: pbravo@bwh.harvard.edu.
Paco E
PE
Bravo
Division of Pulmonary and Critical Care Medicine, University of Washington School of Medicine, Seattle, WA, United States.
Ganesh
G
Raghu
Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States.
David G
DG
Rosenthal
Department of Radiology, University of Washington School of Medicine, Seattle, WA, United States.
Shana
S
Elman
University of Washington School of Medicine, Seattle, WA, United States.
Bradley J
BJ
Petek
Division of Cardiology, University of Washington School of Medicine, Seattle, WA, United States; Department of Radiology, University of Washington School of Medicine, Seattle, WA, United States.
Laurie A
LA
Soine
Department of Radiology, University of Washington School of Medicine, Seattle, WA, United States.
Jeffrey H
JH
Maki
Division of Cardiology, University of Washington School of Medicine, Seattle, WA, United States.
Kelley R
KR
Branch
Division of Cardiology, University of Washington School of Medicine, Seattle, WA, United States.
Sofia C
SC
Masri
Division of Cardiology, University of Washington School of Medicine, Seattle, WA, United States.
Kristen K
KK
Patton
Division of Cardiology, University of Washington School of Medicine, Seattle, WA, United States; Department of Radiology, University of Washington School of Medicine, Seattle, WA, United States.
James H
JH
Caldwell
Division of Cardiology, University of Washington School of Medicine, Seattle, WA, United States.
Eric V
EV
Krieger
D000328:Adult; D000368:Aged; D009202:Cardiomyopathies / Q000000981:diagnostic imaging* / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D012189:Retrospective Studies; D018570:Risk Assessment; D012507:Sarcoidosis / Q000000981:diagnostic imaging* / Q000453:epidemiology