Abstract 12371: Changes in F18-Flurodeoxyglucose Uptake on Serial Cardiac Positron Emission Tomography and Left Ventricular Ejection Fraction in Patients With Cardiac Sarcoidosis
Introduction: Cardiac positron emission tomography (PET) using F18-fluorodeoxyglucose (FDG) has been used to diagnose and monitor cardiac sarcoidosis (CS). It is not yet known whether a reduction in myocardial inflammation, as measured by FDG uptake, is associated with improvement in LV ejection fraction (EF).
Methods: For 23 patients with CS (83% diagnosed by biopsy, 17% clinically) followed by a total of 90 serial PET exams (median 4 per patient), two physicians blinded to EF quantified the maximum standardized uptake value (SUV) and volume of FDG to assess the intensity and extent of FDG uptake on each study. Using gated rubidium rest perfusion images, EF was measured by a physician blind to all clinical and FDG data. To account for clustering and differences in scan frequency, a mixed effects model was used to evaluate the relationship between FDG uptake and changes in EF on interval scans.
Results: Among 23 patients with serial PET exams (mean age 49, 74% male, mean baseline EF 43±13%) the median time between the first and last scan was 2.0 years. Overall, 91% were treated with corticosteroids, 78% with ACE/ARB, 83% with beta-blockers and 83% had ICDs. Mixed modeling demonstrated a significant inverse linear relationship (Figure) with an expected increase in EF of 7.9% per SUV reduction of 10 g/mL (p ≤ 0.008) and an increase of 3.8% per SUV volume reduction of 100 cm3 (p ≤ 0.022).
Conclusions: In a longitudinal cohort of CS patients, a reduction in the intensity and extent of myocardial inflammation on FDG PET is associated with improvement in EF. These data suggest serial PET scanning may help guide titration of immunosuppressive therapy to prevent heart failure in CS.
Figure Legend: Relationship of change in FDG uptake as measured by maximum SUV with change in EF in CS with linear regression obtained via mixed effects modeling shown with 95% CI.
- © 2013 by American Heart Association, Inc.