Cardiovascular 18F-fluoride positron emission tomography-magnetic resonance imaging: A comparison study

Abstract Background 18F-Fluoride uptake denotes calcification activity in aortic stenosis and atherosclerosis. While PET/MR has several advantages over PET/CT, attenuation correction of PET/MR data is challenging, limiting cardiovascular application. We compared PET/MR and PET/CT assessments of 18F-fluoride uptake in the aortic valve and coronary arteries. Methods and results 18 patients with aortic stenosis or recent myocardial infarction underwent 18F-fluoride PET/CT followed immediately by PET/MR. Valve and coronary 18F-fluoride uptake were evaluated independently. Both standard (Dixon) and novel radial GRE) MR attenuation correction (AC) maps were validated against PET/CT with results expressed as tissue-to-background ratios (TBRs). Visually, aortic valve 18F-fluoride uptake was similar on PET/CT and PET/MR. TBRMAX values were comparable with radial GRE AC (PET/CT 1.55±0.33 vs. PET/MR 1.58 ± 0.34, P = 0.66; 95% limits of agreement − 27% to + 25%) but performed less well with Dixon AC (1.38 ± 0.44, P = 0.06; bias (−)14%; 95% limits of agreement − 25% to + 53%). In native coronaries, 18F-fluoride uptake was similar on PET/MR to PET/CT regardless of AC approach. PET/MR identified 28/29 plaques identified on PET/CT; however, stents caused artifact on PET/MR making assessment of 18F-fluoride uptake challenging. Conclusion Cardiovascular PET/MR demonstrates good visual and quantitative agreement with PET/CT. However, PET/MR is hampered by stent-related artifacts currently limiting clinical application.

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18F-sodium fluoride and 18F-fluorodeoxyglucose positron emission tomography for assessment of aortic valve inflammation and calcification in patients with aortic stenosis

Russian Journal of Cardiology ◽

10.15829/1560-4071-2019-12-33-38 ◽

2019 ◽

pp. 33-38

Author(s):

P. M. Murtazalieva ◽

D. V. Ryzhkova ◽

O. B. Irtyuga ◽

E. G. Malev ◽

S. A. Kukushkina ◽

...

Keyword(s):

Positron Emission Tomography ◽

Aortic Valve ◽

Aortic Stenosis ◽

Fdg Pet ◽

Calcium Score ◽

Emission Tomography ◽

Agatston Score ◽

Positron Emission ◽

Pet Ct ◽

Fdg Pet Ct

Aim. To determine the inflammation and calcification activity in aortic stenosis (AS) by assessing the accumulation of 18F-FDG and 18F-NaF in the aortic valve; to study the relationship of the AS severity, aortic calcification and the accumulation of 18F-FDG and 18F-NaF. Material and methods. The study included 62 patients with asymptomatic AS (29 patients with tricuspid (TAV) and 33 with bicuspid (BAV) aortic valve), aged 40 to 70 years. The maximum flow rate at the aortic valve (Vmax) differs from 2,4 m/s to 4,5 m/s. The mean age of patients was 59,44±7,33 years, M:W 1:1. Patients with infective endocarditis and chronic rheumatic heart disease were excluded. The AS severity was assessed according to the standard protocol of transthoracic echocardiography with the use of Vivid 7 ultrasound system (GE,USA). All patients underwent combined positron emission tomography/computed tomography (PET/CT) of the aortic valve using the Discovery 710 system. Evaluation of calcification and inflammation activity of the aortic valve was performed using 8F-NaF and 18F-FDG PET/CT. A quantitative assessment of radiopharmaceuticals accumulation was carried out using uptake ratio indices. The calcium score was calculated using SmartScore 4.0 software.Results. Patients with TAV and BAV were comparable in severity of AS, the median Vmax was 2,9 [2,6; 3,4] m/s and 2,9 [2,3; 3,3] m/s, respectively. Also, TAV and BAV patients did not differ in calcification values (Agatston score 1088 [465; 2192] and 1128 [442; 2391] HU, respectively). The association of 18F-FDG accumulation and AS severity has not been established. At the same time, the association was found between the aortic valve peak velocity and the calcium score (r=0,57, p< 0,0001), as well as the 18F-NaF accumulation values — maximum, mean and maximum to mean (r=0,37, p=0,002; r=0,46, p=0,0001 and r=0,41, p=0,0008, respectively). No association between the accumulation of 18F-FDG and 18F-NaF (r=0,098, p=0,49) was found.Conclusion. It was found that the inflammation according to 18F-FDG PET/CT does not play a significant role in AS pathogenesis. At this time, 18F-NaF PET/CT is a reliable method for the AS diagnosis and valve calcification assessment. It can be used to evaluate the prognosis and effectiveness of therapy in TAV and BAV patients.

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The Usefulness of [18F]F-Fluorodeoxyglucose and [18F]F-Sodium Fluoride Positron Emission Tomography Imaging in the Assessment of Early-Stage Aortic Valve Degeneration after Transcatheter Aortic Valve Implantation (TAVI)—Protocol Description and Preliminary Results

Journal of Clinical Medicine ◽

10.3390/jcm10030431 ◽

2021 ◽

Vol 10 (3) ◽

pp. 431

Author(s):

Danuta Sorysz ◽

Rafał Januszek ◽

Anna Sowa-Staszczak ◽

Anna Grochowska ◽

Marta Opalińska ◽

...

Keyword(s):

Aortic Valve ◽

Emission Tomography ◽

Effective Orifice Area ◽

Orifice Area ◽

Transcatheter Aortic Valve ◽

Positron Emission ◽

Pet Ct ◽

Transvalvular Gradient ◽

Valve Implantation

Transcatheter aortic valve implantation (TAVI) is now a well-established treatment for severe aortic stenosis. As the number of procedures and indications increase, the age of patients decreases. However, their durability and factors accelerating the process of degeneration are not well-known. The aim of the study was to verify the possibility of using [18F]F-sodium fluoride ([18F]F-NaF) and [18F]F-fluorodeoxyglucose ([18F]F-FDG) positron emission tomography/computed tomography (PET/CT) in assessing the intensity of TAVI valve degenerative processes. In 73 TAVI patients, transthoracic echocardiography (TTE) at initial (before TAVI), baseline (after TAVI), and during follow-up, as well as transesophageal echocardiography (TEE) and PET/CT, were performed using [18F]F-NaF and [18F]F-FDG at the six-month follow-up (FU) visit as a part of a two-year FU period. The morphology of TAVI valve leaflets were assessed in TEE, transvalvular gradients and effective orifice area (EOA) in TTE. Calcium scores and PET tracer activity were counted. We assessed the relationship between [18F]F-NaF and [18F]F-FDG PET/CT uptake at the 6 = month FU with selected indices e.g.,: transvalvular gradient, valve type, EOA and insufficiency grade at following time points after the TAVI procedure. We present the preliminary PET/CT ([18F]F-NaF, [18F]F-FDG) results at the six-month follow-up period as are part of an ongoing study, which will last two years FU. We enrolled 73 TAVI patients with the mean age of 82.49 ± 7.11 years. A significant decrease in transvalvular gradient and increase of effective orifice area and left ventricle ejection fraction were observed. At six months, FU valve thrombosis was diagnosed in four patients, while 7.6% of patients refused planned controls due to the COVID-19 pandemic. We noticed significant correlations between valve types, EOA and transaortic valve gradients, as well as [18F]F-NaF and [18F]F-FDG uptake in PET/CT. PET/CT imaging with the use of [18F]F-FDG and [18F]F-NaF is intended to be feasible, and it practically allows the standardized uptake value (SUV) to differentiate the area containing the TAVI leaflets from the SUV directly adjacent to the ring calcifications and the calcified native leaflets. This could become the seed for future detection and evaluation capabilities regarding the progression of even early degenerative lesions to the TAVI valve, expressed as local leaflet inflammation and microcalcifications.

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OPPORTUNISTIC EVALUATION OF BONE MINERAL DENSITY BY PET-CT IN HODGKIN LYMPHOMA PATIENTS

Endocrine Practice ◽

10.4158/ep-2019-0122 ◽

2019 ◽

Vol 25 (9) ◽

pp. 869-876 ◽

Cited By ~ 1

Author(s):

Bar Cohen ◽

Nurith Hiller ◽

Auryan Szalat ◽

Vladimir Vainstein

Keyword(s):

Computed Tomography ◽

Bone Mineral Density ◽

Hodgkin Lymphoma ◽

Bone Mineral ◽

Ct Scans ◽

Mineral Density ◽

Hounsfield Units ◽

Positron Emission ◽

Pet Ct ◽

Ct Attenuation

Objective: Bone density loss and increased risk for osteoporosis are of concern in Hodgkin lymphoma (HL) patients. Routinely performed positron emission tomography–computed tomography (PET-CT) scans could be informative in assessing bone mineral density (BMD). Methods: This retrospective study included 80 adults with newly diagnosed HL treated with standard first-line chemotherapy regimens. PET-CT scans performed at diagnosis (PET-CT1), at the end of chemotherapy (PET-CT2), and at follow-up after remission (PET-CT3) were used to assess BMD changes by measuring lumbar vertebrae CT attenuation. A CT attenuation threshold of 160 Hounsfield units was used to define abnormal BMD. Results: Following chemotherapy, comparison of PET-CT2 with PET-CT1 revealed a mean (standard deviation) 14.2% (10.4%) BMD reduction ( P<.001). On PET-CT3 performed at 14.6 (3.25) months after the last course of chemotherapy, a slight improvement (4.6% [10.4%]) in comparison to PET-CT2 was noted. Twelve patients (15%) converted from normal baseline BMD on PET-CT1 to abnormal BMD after chemotherapy on PET-CT2. Age, baseline BMD, and steroid cumulative dose were associated with BMD decline and risk for abnormal BMD after chemotherapy. No clinical fractures were reported, and only one rib fracture was incidentally captured (1.25%). Conclusion: HL patients treated with common first-line chemotherapies demonstrate a significant decline in bone density on routine PET-CT scans. Opportunistic use of PET-CT scan has the potential to detect HL patients at high risk for developing osteoporosis and to guide clinicians regarding monitoring and intervention. Abbreviations: BMD = bone mineral density; CT = computed tomography; DXA = dual-energy X-ray absorptiometry; HL = Hodgkin lymphoma; HU = Hounsfield units; L = lumbarvertebra; PET-CT = positron emission tomography-computed tomography; T = thoracic vertebra

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P3358Cardiovascular risk, aortic valve microcalcification and vascular microcalcification: is there a link?

European Heart Journal ◽

10.1093/eurheartj/ehz745.0234 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

C Domingues ◽

M Oliveira-Santos ◽

M Castelo-Branco ◽

R Silva ◽

A Gomes ◽

...

Keyword(s):

Cardiovascular Risk ◽

Aortic Valve ◽

Aortic Stenosis ◽

Blood Pool ◽

Pet Ct ◽

Risk Distribution ◽

Group A ◽

Ascvd Risk ◽

The Mean ◽

Group B

Abstract 18F-sodium fluoride (18F-NaF) has been used to evaluate aortic stenosis. It is know that its uptake is related with microcalcification. The purpose of this study is to assess the relationship between 18F-NaF uptake by the aortic valve and by the main arterial vessels and cardiovascular risk. Twenty-five hypertensive patients without known cardiovascular disease or aortic stenosis underwent PET-CT with 18F-NaF. Cardiovascular risk was assessed through the ASCVD risk calculator. The patients had a mean age of 64.0±8.6 years and 56% were males. The mean ASCVD risk was of 28.8±19.0 (IQR: 10–48.5). The uptake of 18F-NaF assessed through the corrected uptake per lesion (CUL = max SUV – mean blood-pool SUV) was of 0.49±0.14 (IQR: 0.44–0.57) and the mean uptake in the aortic, coronary and carotid territories was of 0.66±0.21 (IQR: 0.53 - 0.76).The patients were classified according to the ASCVD: Group A: patients with a risk above the 50thpercentile of the ASCVD risk distribution (50thpercentile=25), 12 patients) and Group B: patients with a risk under or equal to the 50thpercentile of the ASCVD risk distribution, 13 patients. The uptake of 18F-NaF in the aortic valve (AoV)and in the main vascular territories (VT) were evaluated in both groups: A vs B: AoV CUL = 0.57±0.09 vs 0. 42±0.14, p=0.005; VT= 0.78±0.16 vs 0.54±0.20, p=0.003. We also evaluate the relation between AoV uptake and VT uptake and they were significantly related (r=0.69, p=0.0001). In conclusion on this study microcalcification of the aortic valve and in the main vessels, evaluated through 18F-NaF uptake, were related between them and with cardiovascular risk reinforcing the importance of cardiovascular risk prevention in aortic valve degeneration and vascular atherosclerosis.

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