Dario Genovesi1, Giuseppe Vergaro2, Assuero Giorgetti1, Paolo Marzullo1, Michele Scipioni3, Maria Filomena Santarelli4, Angela Pucci5, Gabriele Buda6, Elisabetta Volpi7, Michele Emdin8. 1. Division of Nuclear Medicine, Fondazione Toscana Gabriele Monasterio, Pisa, Italy. 2. Division of Cardiology and Cardiovascular Medicine, Fondazione Toscana Gabriele Monasterio, Pisa, Italy; Institute of Life Science, Scuola Sant'Anna Pisa, Pisa, Italy. 3. Information Engineering Department, University of Pisa, Pisa, Italy. 4. Consiglio Nazionale delle Ricerche, Institute of Clinical Physiology, Pisa, Italy. 5. Histopathology Department Pisa, University Hospital, Pisa, Italy. 6. Department of Clinical and Experimental Medicine, University of Pisa, Italy. 7. Hospital Pharmacy, Fondazione Toscana Gabriele Monasterio, Massa, Italy. 8. Division of Cardiology and Cardiovascular Medicine, Fondazione Toscana Gabriele Monasterio, Pisa, Italy; Institute of Life Science, Scuola Sant'Anna Pisa, Pisa, Italy. Electronic address: emdin@ftgm.it.
Abstract
OBJECTIVES: This study aimed to test the diagnostic value of [18F]-florbetaben positron emission tomography (PET) in patients with suspicion of CA. BACKGROUND: Diagnosis of cardiac involvement in immunoglobulin light-chain-derived amyloidosis (AL) and transthyretin-related amyloidosis (ATTR), which holds major importance in risk stratification and decision making, is frequently delayed. Furthermore, although diphosphonate radiotracers allow a noninvasive diagnosis of ATTR, demonstration of cardiac amyloidosis (CA) in AL may require endomyocardial biopsy. METHODS: Forty patients with biopsy-proven diagnoses of CA (20 ALs, 20 ATTRs) and 20 patients referred with the initial clinical suspicion and later diagnosed with non-CA pathology underwent a cardiac PET/computed tomography scan with a 60-min dynamic [18F]-florbetaben PET acquisition, and 4 10-min static scans at 5, 30, 50, and 110 min after radiotracer injection. RESULTS: Visual qualitative assessment showed intense early cardiac uptake in all subsets. Patients with AL displayed a high, persistent cardiac uptake in all the static scans, whereas patients with ATTR and those with non-CA showed an uptake decrease soon after the early scan. Semiquantitative assessment demonstrated higher mean standardized uptake value (SUVmean) in patients with AL, sustained over the whole acquisition period (early SUVmean: 5.55; interquartile range [IQR]: 4.00 to 7.43; vs. delayed SUVmean: 3.50; IQR: 2.32 to 6.10; p = NS) compared with in patients with ATTR (early SUVmean: 2.55; IQR: 1.80 to 2.97; vs. delayed SUVmean: 1.25; IQR: 0.90 to 1.60; p < 0.001) and in patients with non-CA (early SUVmean: 3.50; IQR: 1.60 to 3.37; vs. delayed SUVmean: 1.40; IQR: 1.20 to 1.60; p < 0.001). Similar results were found comparing heart-to-background ratio and molecular volume. CONCLUSIONS: Delayed [18F]-florbetaben cardiac uptake may discriminate CA due to AL from either ATTR or other mimicking conditions. [18F]-florbetaben PET/computed tomography may represent a promising noninvasive tool for the diagnosis of AL amyloidosis, which is still often challenging and delayed. (A Prospective Triple-Arm, Monocentric, Phase-II Explorative Study on Evaluation of Diagnostic Efficacy of the PET Tracer [18F]-Florbetaben [Neuraceq] in Patients With Cardiac Amyloidosis [FLORAMICAR2]; EudraCT number: 2017-001660-38).
OBJECTIVES: This study aimed to test the diagnostic value of [18F]-florbetaben positron emission tomography (PET) in patients with suspicion of CA. BACKGROUND: Diagnosis of cardiac involvement in immunoglobulin light-chain-derived amyloidosis (AL) and transthyretin-related amyloidosis (ATTR), which holds major importance in risk stratification and decision making, is frequently delayed. Furthermore, although diphosphonate radiotracers allow a noninvasive diagnosis of ATTR, demonstration of cardiac amyloidosis (CA) in AL may require endomyocardial biopsy. METHODS: Forty patients with biopsy-proven diagnoses of CA (20 ALs, 20 ATTRs) and 20 patients referred with the initial clinical suspicion and later diagnosed with non-CA pathology underwent a cardiac PET/computed tomography scan with a 60-min dynamic [18F]-florbetaben PET acquisition, and 4 10-min static scans at 5, 30, 50, and 110 min after radiotracer injection. RESULTS: Visual qualitative assessment showed intense early cardiac uptake in all subsets. Patients with AL displayed a high, persistent cardiac uptake in all the static scans, whereas patients with ATTR and those with non-CA showed an uptake decrease soon after the early scan. Semiquantitative assessment demonstrated higher mean standardized uptake value (SUVmean) in patients with AL, sustained over the whole acquisition period (early SUVmean: 5.55; interquartile range [IQR]: 4.00 to 7.43; vs. delayed SUVmean: 3.50; IQR: 2.32 to 6.10; p = NS) compared with in patients with ATTR (early SUVmean: 2.55; IQR: 1.80 to 2.97; vs. delayed SUVmean: 1.25; IQR: 0.90 to 1.60; p < 0.001) and in patients with non-CA (early SUVmean: 3.50; IQR: 1.60 to 3.37; vs. delayed SUVmean: 1.40; IQR: 1.20 to 1.60; p < 0.001). Similar results were found comparing heart-to-background ratio and molecular volume. CONCLUSIONS: Delayed [18F]-florbetaben cardiac uptake may discriminate CA due to AL from either ATTR or other mimicking conditions. [18F]-florbetaben PET/computed tomography may represent a promising noninvasive tool for the diagnosis of AL amyloidosis, which is still often challenging and delayed. (A Prospective Triple-Arm, Monocentric, Phase-II Explorative Study on Evaluation of Diagnostic Efficacy of the PET Tracer [18F]-Florbetaben [Neuraceq] in Patients With Cardiac Amyloidosis [FLORAMICAR2]; EudraCT number: 2017-001660-38).
Authors: Subha Saeed; Jean Michel Saad; Ahmed Ibrahim Ahmed; Yushui Han; Mouaz H Al-Mallah Journal: Heart Fail Rev Date: 2021-11-07 Impact factor: 4.654
Authors: Weijia Li; Dipan Uppal; Yu-Chiang Wang; Xiaobo Xu; Damianos G Kokkinidis; Mark I Travin; James M Tauras Journal: Diagnostics (Basel) Date: 2021-05-30