Effectiveness of prolonged fasting 18f-FDG PET-CT in the detection of cardiac sarcoidosis

Abstract

Relative to Gallium scintigraphy, PF-PET appears to provide greater accuracy for detecting cardiac sarcoidosis. Our findings also highlight the importance of revising JMHWG to incorporate PF-PET and the importance of adequate prolonged fasting prior to FDG PET imaging.

A joint procedural position statement on imaging in cardiac sarcoidosis: from the Cardiovascular and Inflammation & Infection Committees of the European Association of Nuclear Medicine, the European Association of Cardiovascular Imaging, and the American Society of Nuclear Cardiology

“…SUVs are defined as the radioactivity concentration in the region of interest in BqÁmL -1 /(injected dose in BqÁpatient weight in g -1 ). 55 Various metrics for quantification of FDG uptake in cardiac sarcoidosis have been reported, including the maximal SUV values in the heart (SUV max ), 45,55 the total SUV value of the heart, 55 mean SUV of the heart, 56 heart-to-blood pool SUV ratios, 57 coefficient of variance of SUVs, 58 and the volume, 59 and volume-activity 44,59 of voxels with intensities of FDG SUVs above various thresholds. While these methods have not been rigorously compared head-to-head, there is data to suggest that they perform better than visual assessment of normalized images to assess treatment response.…”

“…[53][54][55]57,69,70 A recent meta-analysis of seven studies demonstrated an overall sensitivity of 89% and a specificity of 78% for FDG-PET. 70 However, these estimates are biased as the lower specificity of PET in some studies may reflect the fact that this test is more sensitive for identifying cardiac sarcoidosis than the JMHW criteria.…”

“…Several studies have compared FDG-PET, either alone or combined with PET MPI, to 67 gallium imaging and have demonstrated improved accuracy for detecting cardiac sarcoid. 42,53,54,57,72 Despite the high diagnostic accuracy of FDG-PET, it is currently not included in the most recent updated (2006) diagnostic criteria of the JMHW, published by the Japan Society of Sarcoidosis and Other Granulomatous Disorders. 9 The more recent HRS Consensus Recommendations 10 suggest that clinical diagnosis of cardiac sarcoidosis is probable if there is histological proof of extracardiac sarcoidosis and one or more findings which include a pattern consistent with cardiac sarcoidosis on imaging [including dedicated cardiac PET, late gadolinium enhancement (LGE) on CMR, positive 67 gallium imaging], unexplained reduced left ventricular ejection fraction (LVEF)\40%, unexplained In summary, FDG-PET is the best clinically available tool for imaging myocardial inflammation.…”

Cardiac Sarcoid: A Clinician's Review on How to Approach the Patient With Cardiac Sarcoid

“…29 Furthermore, in a retrospective examination of 76 patients with suspected CS who underwent 18F-FDG PET and/or gallium scintigraphy for evaluation of CS, Langah et al found that 18F-FDG PET had a sensitivity and specificity of 85% and 90%, respectively, vs 15% and 80%, respectively, for gallium scintigraphy. 30 Overall it can be concluded that 18F-FDG PET has the potential to detect subtle sarcoid-induced changes in myocardium missed by other radionuclide studies, but the test is commonly limited to large tertiary referral centers (Table 1).…”

Accuracy of PET/CT for detection of infective endocarditis: Where are we now?

“…As reported in this manuscript, there are significant variations between the different PET/CT protocols in the literature, since there is still no consensus on the best patient preparation before and during the study. Some authors advocate the importance of a very long fasting period, up to 18 hours before the injection of 18-FDG, 9 while others insist on combining all methods, i.e., the use of a low carbohydrate / high fat diet (Atkins diet) for at least 24 hours but up to 48 hours, a period of fast between 8 and 12 hours and intravenous heparin pre-administration. 10 We definitely think that a rigorous protocol is critical to completely suppress physiological myocardial uptake in order to obtain a better discrimination between normal and abnormal 18F-FDG activity within the myocardium.…”