Volume 16 Supplement 1

Abstracts of the 17th Annual SCMR Scientific Sessions

Open Access

Cardiac MRI and FDG-PET in the diagnosis of cardiac sarcoidosis

  • Richard Coulden1,
  • Hefin Jones1,
  • Emer Sonnex1,
  • Indrajeet Das1 and
  • Jonathan Abele1
Journal of Cardiovascular Magnetic Resonance201416(Suppl 1):P299

https://doi.org/10.1186/1532-429X-16-S1-P299

Published: 16 January 2014

Background

Sarcoidosis is a multisystem disorder with cardiac involvement in 25% of cases [1]. Diagnosis of cardiac sarcoidosis is challenging with FDG-PET and cardiac MRI (CMRI) proving most reliable. We compare FDG-PET and CMRI with delayed enhancement (LGE) in patients with biopsy proven extra-cardiac sarcoidosis being investigated for cardiac involvement.

Methods

30 patients meeting Japanese Ministry of Health & Welfare guidelines [2] for clinical cardiac sarcoidosis were investigated with FDG-PET CT (Gemini TF Philips) and CMRI (Aera 1.5T Siemens) on the same day. Patients undergoing FDG-PET followed a 24 hour low-carbohydrate diet and overnight fast [3]. CMRI examination included SSFP assessment of left ventricular (LV) function, short axis T2-weighted STIR and PSIR-LGE 10 minutes post 0.2 mmol/kg GdDTPA. Images were reviewed by experienced readers blinded to the results of the other examination. FDG-PET was considered positive if any segment (AHA 17 segment model) had an SUVmax > 3.6 (3). CMRI was considered positive if any segment showed 'sarcoid-type' LGE. In no case was edema present on STIR imaging without LGE in the same segment on subsequent PSIR.

Results

FDG-PET and CMRI were positive in 10 patients; FDG-PET +ve and CMRI -ve in 3; FDG-PET -ve and CMRI +ve in 4; both -ve in 13. Distributions of FDG and LGE throughout the myocardium are summarized in Figure 1. In 2 cases where FDG and CMRI were +ve, LGE was in an ischemic pattern and both patients had known recent iscemic events (sub-endocardial). 6 of the remaining 8 had impaired LV function (EF < 50%). All FDG +ve/CMRI -ve cases had intense mediastinal/lung FDG uptake. All 4 FDG -ve/CMRI +ve had either long-standing sarcoidosis ( > 2 years) or absent node/lung FDG activity. Seven of the cases, -ve by both modalities, had no significant or minimal node/lung FDG uptake (SUVmax < 2.5).
Figure 1

LV distribution of LGE (A) and significant myocardial FDG uptake (B) for all 30 patients. By both modalities, cardiac sarcoidosis predominantly involves the lateral wall with relative sparing of the distal anterior wall, distal septum and apex.

Conclusions

Previous single modality studies have suggested sensitivity and specificity for FDG-PET of 89% and 78% and CMRI of 75% and 77% respectively. In our study, 43% showed no cardiac sarcoidosis by either modality and half of these had minimal or no FDG-PET evidence of active sarcoidosis elsewhere. Are these false -ve FDG-PET/CMRI studies or are the clinical criteria too sensitive? Our findings suggest FDG-PET and CMRI-LGE show different degrees of cardiac sarcoid involvement: FDG-PET indicating active inflammatory disease, LGE showing severe edema and scar. Those patients with LGE and no myocardial FDG uptake appear to have 'burnt-out' disease.

Funding

None.

Authors’ Affiliations

(1)
Dept Radiology & Diagnostic Imaging, University of Alberta Hospital

References

  1. Iwai : Sarcoidosis. 1994Google Scholar
  2. Hiraga : Japanese Ministry of Health & Welfare. 1993Google Scholar
  3. Coulden : Eur Radiol. 2012Google Scholar

Copyright

© Coulden et al.; licensee BioMed Central Ltd. 2014

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

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