11C-Pittsburgh B PET Imaging in Cardiac Amyloidosis

• Published in: JACC. Cardiovascular imaging Vol. 8; no. 1; pp. 50 - 59
• Main Authors: Lee, Seung-Pyo, Lee, Eun Seong, Choi, Hongyoon, Im, Hyung-Jun, Koh, Youngil, Lee, Min-Ho, Kwon, Ji-Hyun, Paeng, Jin Chul, Kim, Hyung-Kwan, Cheon, Gi Jeong, Kim, Yong-Jin, Kim, Inho, Yoon, Sung-Soo, Seo, Jeong-Wook, Sohn, Dae-Won
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.01.2015
• Subjects: Aged; Aged, 80 and over; Amyloidosis - diagnosis; Benzothiazoles; cardiac amyloidosis; cardiac magnetic resonance; Cardiomyopathies - diagnosis; Echocardiography; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Pittsburgh B compound; Positron-Emission Tomography; Tomography, X-Ray Computed; RV; echocardiography; PiB; Pittsburgh B compound; CMR; LV; LGE; CT; SUV; cardiac amyloidosis; positron emission tomography; cardiac magnetic resonance; PET
• ISSN: 1936-878X; 1876-7591; 1876-7591
• DOI: 10.1016/j.jcmg.2014.09.018

This study sought to investigate the efficacy of 11C-Pittsburgh B (PiB) positron emission tomography (PET)/computed tomography (CT) in the diagnosis of cardiac amyloidosis. The PiB compound has been promising for detection of amyloid deposits in the brain. A total of 22 consecutive patients were enrolled in this prospective pilot study of monoclonal gammopathy patients with suspected cardiac amyloidosis. The study consisted of a series of 11C-PiB PET/CT, echocardiography, cardiac magnetic resonance, and endomyocardial biopsy within a 1-month period. In addition, 10 normal subjects were recruited to determine the most optimal cut-off value for a positive 11C-PiB PET/CT scan. Among the 22 patients, 15 patients were diagnosed as cardiac amyloidosis by endomyocardial biopsy and 5 patients had undergone chemotherapy previously before the 11C-PiB PET/CT. There were no differences in echocardiographic parameters between patients with versus without cardiac amyloidosis, except for a marginal difference in the left ventricular end-diastolic dimension (median 41.0 mm [range 33.0 to 49.0 mm] vs. 50.0 mm [range 38.0 to 55.0 mm], p = 0.066). 11C-PiB PET/CT was positive in 13 of 15 biopsy-proven cardiac amyloidosis patients, whereas none of the patients without cardiac amyloidosis demonstrated positive 11C-PiB PET/CT scan results. The maximal myocardium-to-blood cavity ratio was significantly different between patients with versus without cardiac amyloidosis (median 3.9 [range 1.7 to 19.9] vs. 1.0 [range 0.8 to 1.2], p < 0.001). In association with the significant difference of 11C-PiB uptake in the myocardium between the chemotherapy naïve versus the previous chemotherapy group (median 10.4 [range 1.7 to 19.9] vs. 2.3 [range 1.7 to 3.8], p = 0.014), all except 1 patient among the 5 previously treated patients had responded to chemotherapy by serum free light chain assay results at the time of 11C-PiB PET/CT scan. 11C-PiB PET/CT may be valuable for the diagnosis of cardiac amyloidosis noninvasively. Whether 11C-PiB PET/CT may be a good surrogate marker of active light chain deposition in the myocardium warrants further investigation in a larger number of patients.