In vivo visualization of amyloid deposits in the heart with 11C-PIB and PET.

Journal of Nuclear Medicine

PubMedID: 23238792

Antoni G, Lubberink M, Estrada S, Axelsson J, Carlson K, Lindsjö L, Kero T, Långström B, Granstam SO, Rosengren S, Vedin O, Wassberg C, Wikström G, Westermark P, Sörensen J. In vivo visualization of amyloid deposits in the heart with 11C-PIB and PET. J Nucl Med. 2013;54(2):213-20.
UNLABELLED
Cardiac amyloidosis is a differential diagnosis in heart failure and is associated with high mortality. There is currently no noninvasive imaging test available for specific diagnosis. N-[methyl-(11)C]2-(4'-methylamino-phenyl)-6-hydroxybenzothiazole ((11)C-PIB) PET is used in the evaluation of brain amyloidosis. We evaluated the potential use of (11)C-PIB PET in systemic amyloidosis affecting the heart.

METHODS
Patients (n = 10) diagnosed with systemic amyloidosis-including heart involvement of either monoclonal immunoglobulin light-chain (AL) or transthyretin (ATTR) type-and healthy volunteers (n = 5) were investigated with PET/CT using (11)C-PIB to study cardiac amyloid deposits and with (11)C-acetate to measure myocardial blood flow to study the impact of global and regional perfusion on PIB retention.

RESULTS
Myocardial (11)C-PIB uptake was visually evident in all patients 15-25 min after injection and was not seen in any volunteer. A significant difference in (11)C-PIB retention in the heart between patients and healthy controls was found. The data indicate that myocardial amyloid deposits in patients diagnosed with systemic amyloidosis could be visualized with (11)C-PIB. No correlation between (11)C-PIB retention index and myocardial blood flow as measured with (11)C-acetate was found on the global level, whereas a positive correlation on the segmental level was seen in a single patient.

CONCLUSION
(11)C-PIB and PET could be a method to study systemic amyloidosis of type AL and ATTR affecting the heart and should be investigated further both as a diagnostic tool and as a noninvasive method for treatment follow-up.