Feasibility of somatostatin receptor-targeted imaging for detection of myocardial inflammation: A pilot study

Paco E. Bravo, Navkaranbir Bajaj, Robert F. Padera, Victoria Morgan, Jon Hainer, Courtney F. Bibbo, Meagan Harrington, Mi Ae Park, Hyewon Hyun, Matthew Robertson, Neal K. Lakdawala, John Groarke, Garrick C. Stewart, Sharmila Dorbala, Ron Blankstein, Marcelo F. Di Carli

Research output: Contribution to journalArticlepeer-review

6 Scopus citations

Abstract

Background: Gallium-68 Dotatate binds preferentially to somatostatin receptor (sstr) subtype-2 (sstr-2) on inflammatory cells. We aimed at investigating the potential clinical use of sstr-targeted imaging for the detection of myocardial inflammation. Methods: Thirteen patients, with suspected cardiac sarcoidosis (CS) based on clinical history and myocardial uptake on recent fluorine-18 fluorodeoxyglucose (FDG) PET, were enrolled to undergo Dotatate PET after FDG-PET (median time 37 days [IQR 25-55]). Additionally, we investigated ex-vivo the immunohistochemistry expression of sstr-2 in 3 explanted sarcoid hearts. Results: All FDG scans showed cardiac uptake (focal/multifocal = 6, focal on diffuse/heterogeneous = 7), and 46% (n = 6) extra-cardiac uptake (mediastinal/hilar). In comparison, Dotatate scans showed definite abnormal cardiac uptake (focal/multifocal) in 4 patients, probably abnormal (heterogenous/patchy) in 3, and negative uptake in 6 cases. Similarly, 6 patients had increased mediastinal/hilar Dotatate uptake. Overall concordance of FDG and Dotatate uptake was 54% in the heart and 100% for thoracic nodal activity. Quantitatively, FDG maximum standardized uptake value was 5.0 times [3.8-7.1] higher in the heart, but only 2.25 times [1.7-3.0; P =.019] higher in thoracic nodes relative to Dotatate. Ex-vivo, sstr-2 immunostaining was weakly seen within well-formed granulomas in all 3 examined sarcoid heart specimens with no significant staining of background myocardium or normal myocardium. Conclusion: Our preliminary data suggest that, compared to FDG imaging, somatostatin receptor-targeted imaging may be less sensitive for the detection of myocardial inflammation, but comparable for detecting extra-cardiac inflammation.

Original languageEnglish (US)
Pages (from-to)1089-1099
Number of pages11
JournalJournal of Nuclear Cardiology
Volume28
Issue number3
DOIs
StatePublished - Jun 2021
Externally publishedYes

Keywords

  • PET
  • Sarcoidosis
  • myocardial inflammation
  • somatostatin receptor

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Cardiology and Cardiovascular Medicine

Fingerprint

Dive into the research topics of 'Feasibility of somatostatin receptor-targeted imaging for detection of myocardial inflammation: A pilot study'. Together they form a unique fingerprint.

Cite this