Abstract 16868: Extent and Severity of Perfusion Metabolism Mismatch is Associated With Adverse Events in Patients Undergoing FDG-PET Imaging for Sarcoidosis
Introduction: Cardiac PET with FDG imaging has been found to have diagnostic and prognostic value in cardiac sarcoidosis. However, prior work has utilized a binary grading (both normal, one abnormal, both abnormal) of perfusion (Rb82) and metabolism (FDG) for prognostication. We evaluated the prognostic value of semiquantitative assessment of perfusion abnormality and FDG uptake.
Methods: We identified 203 patients (age 52 +/- 11, 46% male, 60% Caucasian) who underwent FDG-PET for evaluation of cardiac sarcoidosis and were followed for events (death, cardiac arrest, aborted ventricular tachycardia or heart transplantation; mean follow-up 1.8 years). Both resting perfusion (Summed rest score[SRS]) and FDG uptake were scored on a 0-4 scale/17 segment model. The coefficient of variation (CoV), defined as the FDG uptake standard deviation divided by its mean, was calculated after obtaining standardized uptake values. The association between SRS, FDG uptake, and adverse cardiac events was evaluated using multivariable Cox modeling.
Results: In all, 61 patients (30%) met the composite endpoint. Either a perfusion or metabolism defect on FDG-PET was found in 109 patients. After Cox model adjustment for a clinical score, a medication score, ejection fraction, and prior history of VT (stratified by ICD presence), neither binary grading for presence or absence of FDG and perfusion abnormalities, rest defect and FDG-uptake extent, nor SRS and FDG-uptake added incremental information. Only the SRS in segments with abnormal FDG uptake (hazard ratio[HR] 1.23, p=0.007) and the CoV (HR 1.05, p=0.04) were associated with adverse cardiac events and added incremental information (Figure 1).
Conclusions: In patients who underwent FDG-PET imaging for evaluation of cardiac sarcoidosis, only the SRS of segments with abnormal FDG uptake and CoV were associated with adverse cardiac events after extensive risk adjustment.
Author Disclosures: B. Sperry: None. B.K. Tamarappoo: None. J. Oldan: None. O. Javed: None. D. Culver: None. R. Brunken: None. R. Hachamovitch: None.
- © 2016 by American Heart Association, Inc.