Table 1.
Summary of a series of published studies of nuclear imaging in cardiac amyloidosis from 2020 to 2021.
| First Author | Publication Year | Radiotracer | Method | Results |
|---|---|---|---|---|
| Caobelli et al. [39] | 2020 | 99mTc-DPD | Retrospective single-center study including 13 patients with 8 ATTR cardiac amyloidosis and 5 not. | Myocardial SUVmax and SUVpeak showed strong correlation with Perugini score but a great degree of overlap between patients in Perugini score 2 and 3. |
| Scully et al. [46] | 2020 | 99mTc-DPD | Single-center, retrospective study of 100 DPD scan (40 were Perugini grade 0, 12 were grade 1, 41 were grade 2, and 7 were grade 3). | SUV retention index which is calculated as: ((Cardiac SUVpeak/Vertebral SUVpeak) × paraspinal muscle SUVpeak) increased across all Perugini grades. Cardiac SUVpeak and SUV retention index had excellent diagnostic accuracy with the area under the curve being 0.999. |
| Wollenweber et al. [47] | 2020 | 99mTc-DPD | 32 patients with bioptically-proven or suspected cardiac ATTR amyloidosis received a DPD total body bone scan with additional SPECT/CT. | Patients with Perugini grade 2 and 3 can be clearly separated from those with Perugini grade 0 and 1 with a SUVpeak cut-off of 3.1. |
| Löfbacka et al. [48] | 2020 | 99mTc-DPD | 48 patients with genetically-verified hereditary ATTR cardiac amyloidosis and positive 99mTc-DPD SPECT/CT were assessed manually for amyloid burden. | Statistically significant correlation between DPD uptake and all echocardiographic strain parameters in all regions, as well as the biomarkers of troponin and logarithmic NT-proBNP. |
| Masri et al. [52] | 2020 | 99mTc-PYP | 233 patients with suspected ATTR cardiac amyloidosis underwent planar and SPECT imaging at 1 and 3 hours with a positive scan considered as visual grades ≥ 2 and heart to contralateral ratios ≥ 1.5 | 1-hour and 3-hour protocols have identical SPECT results. Planar imaging at 1 hour had 98% sensitivity and 96% specificity. |
| Asif et al. [54] | 2020 | 99mTc-PYP | 99mTc-PYP scintigraphy was performed including 1-hour planar imaging assessing visual score as well as H/CL ratio and SPECT | Visual score had a diagnostic accuracy of 98% for ATTR cardiac amyloidosis but addition of H/CL ratio reduced the accuracy. SPECT is necessary to perform to prevent misdiagnoses. |
| Tamarappoo et al. [55] | 2020 | 99mTc-PYP/Tl-201 | Dual isotope of 99mTc-PYP/Tl-201 SPECT was performed in 112 patients suspicious of cardiac amyloidosis (39 ATTR, 26 AL, 47 no amyloidosis) and compared with single isotope. H/CL ratio was calculated. | Interobserver agreement of visual assessment was better with dual-isotope SPECT. Area under the curve for ATTR cardiac amyloidosis by visual assessment and H/CL ratio were higher with dual-isotope SPECT than single-isotope SPECT. |
| Ochi et al. [56] | 2020 | 99mTc-PYP | 39 patients with wild-type ATTR cardiac amyloidosis with 8 patients in group A who were diagnosed before the introduction of hs-cTnT and 99mTc-PYP scintigraphy and 31 patients in group B who were diagnosed after the introduction of the two tools. | Increased diagnostic yield in patients who used the combined approach using hs-cTnT and 99mTc-PYP scintigraphy. |
| Takasone et al. [57] | 2020 | 99mTc-PYP, 11C-PiB | 17 patients with AL cardiac amyloidosis, 22 patients with hereditary ATTR cardiac amyloidosis, and 8 patients with wild-type ATTR cardiac amyloidosis underwent both 11C-PiB PET imaging and 99mTc-PYP scintigraphy. | All patients with cardiac amyloidosis are detectable by 99mTc-PYP or 11C-PiB PET imaging. The combination of positive 11C-PiB PET and negative 99mTc-PYP was observed in all AL cardiac amyloidosis and early onset V30M hereditary ATTR cardiac amyloidosis, while the combination of positive 99mTc-PYP and negative 11C-PiB PET was consistent in all wild-type ATTR cardiac amyloidosis, as well as the late-onset V30M and non-V30M hereditary ATTR cardiac amyloidosis. |
| Rosengren et al. [58] | 2020 | 11C-PiB | A dual-center study included 51 subjects with 36 patients with known cardiac amyloidosis and increased wall thickness (15 AL, 21 ATTR) and 15 control patients. All the subjects underwent 11C-PiB PET imaging and echocardiography. | High diagnostic accuracy of both visual inspection and semi-quantitative methods of 11C-PiB PET imaging to distinguish cardiac amyloidosis from controls. The uptake of 11C-PiB was significantly higher in AL cardiac amyloidosis than ATTR cardiac amyloidosis. |
| Lee et al. [59] | 2020 | 11C-PiB | 41 chemotherapy-naïve AL cardiac amyloidosis patients were enrolled. Myocardial uptake of 11C-PiB on PET was compared with endomyocardial biopsy for quantification of amyloid deposit. | The degree of myocardial 11C-PiB uptake is significantly higher in patients with cardiac amyloidosis and higher degrees of uptake was associated with lowest survival from death, heart transplantation and acute decompensated heart failure. |
| Genovesi et al. [60] | 2021 | 18F-florbetaben | 40 patients with biopsy-proven diagnoses of cardiac amyloidosis (20 AL amyloidosis, 20 ATTR amyloidosis) and 20 patients with non-cardiac amyloidosis pathology. | Patients with AL amyloidosis have higher mean SUV, heart-to-background uptake ratio, and molecular volume than ATTR amyloidosis and patients with non-cardiac amyloidosis. |
| Andrews et al. [61] | 2020 | 18F-fluoride | A prospective multicenter study included 53 patients (10 ATTR and 8 AL cardiac amyloidosis, 13 controls and 22 with aortic stenosis). All patients were scanned by 18F-fluoride PET/MRI. SUV and tissue-to-background ratio (TBRmean) were obtained in the septum and areas of late gadolinium enhancement. | TBRmean values are higher in ATTR amyloidosis than controls and those with AL amyloidosis. A TBRmean threshold >1.14 in areas of late gadolinium enhancement has 100% sensitivity and 100% specificity for ATTR amyloidosis compared to AL amyloidosis. |
| Zhang et al. [62] | 2020 | 18F-sodium fluoride and 99mTc-PYP | 12 subjects with ATTR cardiac amyloidosis and 5 controls underwent 18F-sodium fluoride and 99mTc-PYP-SPECT/CT. | Visual assessment of 18F-sodium fluoride PET/CT had a sensitivity of 25% for ATTR cardiac amyloidosis when compared with 100% sensitivity in 99mTc-PYP-SPECT/CT. |
99mTc-DPD: 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid; 99mTc-PYP: 99mTc-pyrophosphate; 11C-PiB: 11C-Pittsburgh compound B.