PurposeArterial inflammation and vascular calcification are regarded as early prognostic markers of cardiovascular disease (CVD). In this study we investigated the relationship between CVD risk and arterial inflammation (18F-FDG PET/CT imaging), vascular calcification metabolism (Na18F PET/CT imaging), and vascular calcium burden (CT imaging) of the thoracic aorta in a population at low CVD risk.MethodsStudy participants underwent blood pressure measurements, blood analyses, and 18F-FDG and Na18F PET/CT imaging. In addition, the 10-year risk for development of CVD, based on the Framingham risk score (FRS), was estimated. CVD risk was compared across quartiles of thoracic aorta 18F-FDG uptake, Na18F uptake, and calcium burden on CT.ResultsA total of 139 subjects (52 % men, mean age 49 years, age range 21 – 75 years, median FRS 6 %) were evaluated. CVD risk was, on average, 3.7 times higher among subjects with thoracic aorta Na18F uptake in the highest quartile compared with those in the lowest quartile of the distribution (15.5 % vs. 4.2 %; P < 0.001). CVD risk was on average, 3.7 times higher among subjects with a thoracic aorta calcium burden on CT in the highest quartile compared with those in the lowest two quartiles of the distribution (18.0 % vs. 4.9 %; P < 0.001). CVD risk was similar in subjects in all quartiles of thoracic aorta 18F-FDG uptake.ConclusionOur findings indicate that an unfavourable CVD risk profile is associated with marked increases in vascular calcification metabolism and vascular calcium burden of the thoracic aorta, but not with arterial inflammation.Electronic supplementary materialThe online version of this article (doi:10.1007/s00259-016-3552-9) contains supplementary material, which is available to authorized users.

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Delayed (18)FDG PET/CT imaging at 180 minutes improves quantitation of atherosclerotic plaque inflammation over imaging at 90 minutes. Therefore, the optimal acquisition time-point to assess atherosclerotic plaque inflammation lies beyond the advocated time-point of 90 minutes after (18)FDG administration.

The early detection of atherosclerotic disease is vital to the effective prevention and management of life-threatening cardiovascular events such as myocardial infarctions and cerebrovascular accidents. Given the potential for positron emission tomography (PET) to visualize atherosclerosis earlier in the disease process than anatomic imaging modalities such as computed tomography (CT), this application of PET imaging has been the focus of intense scientific inquiry. Although 18F-FDG has historically been the most widely studied PET radiotracer in this domain, there is a growing body of evidence that 18F-NaF holds significant diagnostic and prognostic value as well. In this article, we review the existing literature on the application of 18F-FDG and 18F-NaF as PET probes in atherosclerosis and present the findings of original animal and human studies that have examined how well 18F-NaF uptake correlates with vascular calcification and cardiovascular risk.

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ObjectiveTo compare the diagnostic accuracy of the following imaging techniques in the detection of spine metastases, using magnetic resonance imaging (MRI) as a reference: whole-body bone scintigraphy (WBS) with technetium-99m-MDP, [18F]-sodium fluoride (NaF) positron emission tomography (PET)/computed tomography (CT) and [ Patients and MethodsThe study entry criteria were biopsy-proven prostate cancer, a positive WBS consistent with bone metastases, and no history of androgen deprivation. Within 30 days of informed consent, trial scans were performed in random order. Scans were interpreted blindly for the purpose of a lesion-based analysis. The primary target variable was bone lesion (malignant/ benign) and the 'gold standard' was MRI. ResultsA total of 50 men were recruited between May 2009 and March 2012. Their mean age was 73 years, their median PSA level was 84 ng/mL, and the mean Gleason score of the tumours was 7.7. A total of 46 patients underwent all four scans, while four missed one PET/CT scan. A total of 526 bone lesions were found in the 50 men: 363 malignant and 163 non-malignant according to MRI. Sensitivity, specificity, positive and negative predictive values and accuracy were: WBS: 51, 82, 86, 43 and 61%; 54, 82, 78 and 81%; 91, 95, 75 and 87%, respectively. ConclusionsWe found that FCH-PET/CT and NaF-PET/CT were superior to WBS with regard to detection of prostate cancer bone metastases within the spine. The present results call into question the use of WBS as the method of choice in patients with hormone-naïve prostate cancer.

The rapidly rising prevalence and cost of Alzheimer’s disease (AD) in recent decades has made the imaging of amyloid-β (Aβ) deposits the focus of intense research. Several amyloid imaging probes with purported specificity for Aβ plaques are currently at various stages of FDA approval. However, a number of factors appear to preclude these probes from clinical utilization. As the available “amyloid specific” PET imaging probes have failed to demonstrate diagnostic value and have shown limited utility for monitoring therapeutic interventions in humans, a debate on their significance has emerged. The aim of this review is to identify and discuss critically the scientific issues contributing to the extensive inconsistencies reported in the literature on their purported in vivo amyloid specificity and potential utilization in patients.

This study evaluates the relative importance of several mechanisms possibly involved in the natriuresis elicited by slow sodium loading, i.e. the renin-angiotensin-aldosterone system (RAAS), mean arterial blood pressure (MAP), glomerular filtration rate (GFR), atrial natriuretic peptide (ANP), oxytocin and nitric oxide (NO). Eight seated subjects on standardised sodium intake (30 mmol NaCl day _1 ) received isotonic saline intravenously (NaLoading: 20 mmol Na + kg _1 min _1 or ~11 ml min _1 for 240 min). NaLoading did not change MAP or GFR (by clearance of 51 Cr-EDTA). Significant natriuresis occurred within 1 h (from 9 ± 3 to 13 ± 2 mmol min _1 ). A 6-fold increase was found during the last hour of infusion as plasma renin activity, angiotensin II (ANGII) and aldosterone decreased markedly. Sodium excretion continued to increase after NaLoading. During NaLoading, plasma renin activity and ANGII were linearly related (R = 0.997) as were ANGII and aldosterone (R = 0.999). The slopes were 0.40 pM ANGII (mi.u. renin activity) _1 and 22 pM aldosterone (pM ANGII) _1. Plasma ANP and oxytocin remained unchanged, as did the urinary excretion rates of cGMP and NO metabolites (NO x ). In conclusion, sodium excretion may increase 7-fold without changes in MAP, GFR, plasma ANP, plasma oxytocin, and cGMP-and NO x excretion, but concomitant with marked decreases in circulating RAAS components. The immediate renal response to sodium excess appears to be fading of ANGII-mediated tubular sodium reabsorption. Subsequently the decrease in aldosterone may become important.