Identification of cardiac sarcoidosis with (13)N-NH(3)/(18)F-FDG PET.
To our knowledge, no study investigating the usefulness of cardiac PET for detection of myocardial involvement of sarcoidosis is available. We investigated whether (13)N-NH(3)/(18)F-FDG PET could identify cardiac involvement in patients with sarcoidosis.


METHODS
Seventeen patients with cardiac sarcoidosis underwent cardiac (13)N-NH(3)/(18)F-FDG PET under fasting condition. Systemic sarcoidosis was diagnosed by histologically proven noncaseating epithelioid granuloma, and cardiac sarcoidosis was diagnosed according to the Japanese Ministry of Health and Welfare guidelines for diagnosing cardiac sarcoidosis.


RESULTS
Only 6 patients exhibited myocardial (201)Tl defects and only 3 patients exhibited abnormal (67)Ga accumulation in the heart. Thirteen patients exhibited (13)N-NH(3) defects, and 14 patients exhibited increased (18)F-FDG uptake in the heart; 12 patients exhibited both (13)N-NH(3) defects and increased (18)F-FDG uptake, 2 patients exhibited increased (18)F-FDG uptake but no (13)N-NH(3) defect, and 1 patient exhibited (13)N-NH(3) defects but no increased (18)F-FDG uptake. (13)N-NH(3) defects were observed frequently in the basal anteroseptal wall of the left ventricle, and increased (18)F-FDG uptake was observed frequently in the basal and midanteroseptal-lateral wall of the left ventricle. Involvement of the apex was rare. Seven patients were treated with steroid hormone and underwent follow-up cardiac PET 1 mo after steroid therapy. (13)N-NH(3) defects exhibited no significant change after steroid therapy, whereas increased (18)F-FDG uptake was markedly diminished in size and intensity in 5 patients and disappeared completely in 2 patients.


CONCLUSIONS
Our findings suggest that cardiac (13)N-NH(3)/(18)F-FDG PET is the most useful method both for the identification of cardiac involvement of sarcoidosis and for the assessment of cardiac sarcoidosis disease activity.
Yamagishi
Hiroyuki
H
Department of Internal Medicine and Cardiology, Osaka City University Graduate School of Medicine, Osaka City University, Osaka, Japan. yamagishi@med.osaka-cu.ac.jp
Shirai
Naoya
N
Takagi
Masahiko
M
Yoshiyama
Minoru
M
Akioka
Kaname
K
Takeuchi
Kazuhide
K
Yoshikawa
Junichi
J
D000328:Adult; D000368:Aged; D000641:Ammonia / Q000493:pharmacokinetics; D002247:Carbon Isotopes / Q000493:pharmacokinetics; D009202:Cardiomyopathies / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012507:Sarcoidosis / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000378:metabolism; D012680:Sensitivity and Specificity; D014018:Tissue Distribution; D014055:Tomography, Emission-Computed / Q000379:methods*
D002247:Carbon Isotopes; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D000641:Ammonia