Relationship between Epicardial Adipose Tissue and Coronary Vascular Function in Patients with Normal Myocardial Perfusion by 82Rb PET/TC

Background: Epicardial adipose tissue (EAT) is the visceral fat depot of the heart and it directly influences myocardial homeostasis through vasocrine and paracrine mechanism. A reduced coronary flow reserve (CFR) reflects not only the presence of coronary artery stenosis but also coronary vascular dysfunction. There are a few evidences of a direct correlation between increased EAT and impaired CFR in small patients’ population with suspected or known coronary artery disease (CAD). However, this association has not been not fully investigated. Purpose: We assessed the relationship between EAT and CFR in patients with suspected or known CAD and normal myocardial perfusion imaging. Methods: From a pool of 512 subjects referred for the evaluation of suspected or known CAD to stress-rest 82Rb PET/CT, only 270 patients showing normal MPI were considered. CAC score was measured according to the Agatston method. Using unenhanced CT images for CAC, EAT volume was measured (cm3). The ln (CAC+1) score and ln (EAT) transformation were used to reduce heteroscedasticity. Myocardial perfusion was assessed using standardized segmentation of 17 myocardial regions. Myocardial perfusion was considered normal when the summed stress score was <3. Absolute myocardial blood flow (MBF) was computed (in milliliters per minute per gram) from the dynamic rest and stress imaging series. CFR was defined as the ratio of hyperemic to baseline MBF and CFR < 2 was considered reduced. Results: Among 270 patients with normal MPI, 93 (35%) patients showed reduced CFR and 177 (65%) normal CFR. Compared to patients with normal CFR, those with impaired CFR were older (P<0.001) and showed higher values of ln (CAC+1), (P<0.05), EAT thickness (P<0.01) and ln (EAT) volume (P<0.001). At univariable and multivariable logistic regression analyses, although age, ln (CAC+1) and ln (EAT) volume resulted significant predictors of reduced CFR, only age and ln (EAT) volume were independently associated with reduced CFR (P<0.001 and P<0.05). Accordingly, at incremental analysis, while a model including clinical data and ln (CAC+1) score did not show significant difference as compared to a model including only clinical data (global chi-square from 23.3 to 23.5, P=0.65), the addition of ln (EAT) volume to clinical data significantly increased the global chi-square of the model (from 23.3 to 28.5, P<0.05).In addition, a significant correlation was observed between ln (EAT) volume and CFR (r= −.229, p value <0.05) in patients with CAC score =0 (n=114) while such a relationship was not significant in patients with documented CAC (n=156) (r= −.101, p value N.S.) Conclusion In patients with suspected or known CAD and normal MPI age and EAT are strongly associated with reduced CFR and hyperemic MBF confirming that visceral fat depot may directly influence coronary vascular function. Thus, EAT evaluation may play a major role in the identification of coronary vascular dysfunction even in patients with normal MPI. In particular, it could be useful to consider EAT in patients with to no evidence of coronary calcium burden

Nuclear cardiac imaging between implementation and globalization: The key role of integration

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Budget impact analysis of the use of daclatasvir in Italy for the treatment of Hepatitis C Virus (HCV) genotype 3 patients

BACKGROUND: Hepatitis C Virus (HCV) infection represents a global health problem, leading to chronic cirrhosis, hepatocellular carcinoma (HCC), hepatic decompensation and liver transplant. The aim of the study was the evaluation of the impact on the budget of the Italian National Health Service (INHS) of the use of Daclatasvir (DCV) for the treatment of HCV genotype 3 in patients with advanced fibrosis.METHODS: An analytical decision model with a five year time horizon was implemented. Two scenarios were considered: a. 100% of market share for Interferon (INF-α)+Ribavirin (RBV)+Sofosbuvir (SOF) for 12 weeks; b. SOF+DCV+RBV for 24 weeks with annual market shares of 50% in 2015 and 2016, 55% in 2017 and 2018, 60% in 2019, and INF-α+RBV+SOF for 12 weeks with the remaining market shares. Every annual cycle a percentage of patients equal to the effectiveness of the antiviral treatment reach a sustained virologic response and during the first year of treatment patients may experience treatment related adverse events. The costs considered (2015) are those of the antiviral therapy, and direct medical costs for health state and adverse events management. Univariate and multivariate sensitivity analyses were performed.RESULTS: DCV would lead to an increase of the costs for the INHS (year 1 +21.31 millions, year 2 +21.35 millions, year 3 + 23.37 millions, year 4 + 23.26 millions and year 5 +16.37 millions). The sensitivity analysis confirmed the robustness of the results.CONCLUSIONS: The use of DCV is likely to have a short term impact on the INHS budget increasing resources use compared to the sole use of INF-α+RBV+SOF. However, a trend of reduction of the costs increase is observed due to the management of health states and adverse events which may lead to the possibility to reduce costs in the long term

Insights into Myocardial Perfusion PET Imaging: the Coronary Flow Capacity

Purpose of Review The present work summarizes the clinical relevance of coronary flow capacity (CFC) with an eye on future perspectives. Recent findings CFC concept has been recently introduced providing a comprehensive framework for coronary physiology evaluation. Summary It has been widely demonstrated that coronary artery disease (CAD) is a complex disease with a multifactorial etiology resulting from different pathogenic mechanisms. Cardiac positron emission tomography (PET) currently represents the gold standard for CAD assessment, providing absolute myocardial perfusion data including coronary flow reserve (CFR), calculated as the ratio of hyperemic to rest absolute myocardial blood flows. CFC can be obtained from dynamic PET images by plotting the primary stress perfusion data and CFR values for each pixel on a graph of predefined exact ranges. The routine evaluation of this parameter may add diagnostic and prognostic value to clinical and conventional imaging data

Metodi bibliometrici e revisione dei pari per la valutazione della ricerca: un confronto metodologico

The Italian Research Evaluation exercise for the period 2004-2010 has analyzed almost 185,000 among articles, books, patents and other scientific products submitted by Italian Universities and other public research bodies. In most cases, scientific publications have been peer reviewed; however, in hard sciences, medicines, engineering and economics, bibliometric indicators have also been used. For those areas, we have extracted a representative sample of scientific products, equal to the 10% of the reference population of submitted products, to be evaluated both with peer review and biblometric methods. Our analysis shows that peer review and bibliometric evaluations exhibit a level of concordance higher than that observed among two different reviewers of the same article. In almost any scientific discipline, however, there is a systematic difference among peer and bibliometric evaluations: more specifically, bibliometric scores are on average significantly higher than those obtained with the peer review. Overall, our results obtained fully support the choice adopted in the Italian exercise of using both evaluation techniques in order to assess the quality of Italian research institutions

Cardiac hybrid imaging: novel tracers for novel targets

Non-invasive cardiac imaging has explored enormous advances in the last few decades. In particular, hybrid imaging represents the fusion of information from multiple imaging modalities, allowing to provide a more comprehensive dataset compared to traditional imaging techniques in patients with cardiovascular diseases. The complementary anatomical, functional and molecular information provided by hybrid systems are able to simplify the evaluation procedure of various pathologies in a routine clinical setting. The diagnostic capability of hybrid imaging modalities can be further enhanced by introducing novel and specific imaging biomarkers. The aim of this review is to cover the most recent advancements in radiotracers development for SPECT/CT, PET/CT, and PET/MRI for cardiovascular diseases

Metodi bibliometrici e revisione dei pari per la valutazione della ricerca: un confronto metodologico

The Italian Research Evaluation exercise for the period 2004-2010 has analyzed almost 185,000 among articles, books, patents and other scientific products submitted by Italian Universities and other public research bodies. In most cases, scientific publications have been peer reviewed; however, in hard sciences, medicines, engineering and economics, bibliometric indicators have also been used. For those areas, we have extracted a representative sample of scientific products, equal to the 10% of the reference population of submitted products, to be evaluated both with peer review and biblometric methods. Our analysis shows that peer review and bibliometric evaluations exhibit a level of concordance higher than that observed among two different reviewers of the same article. In almost any scientific discipline, however, there is a systematic difference among peer and bibliometric evaluations: more specifically, bibliometric scores are on average significantly higher than those obtained with the peer review. Overall, our results obtained fully support the choice adopted in the Italian exercise of using both evaluation techniques in order to assess the quality of Italian research institutions

Epidemiology, patient profile, and health care resource use for hepatitis C in Italy

The objectives of this study were to estimate the prevalence of Hepatitis C among six Italian Local Health Units (LHUs), to describe patient and antiviral drug characteristics, and to estimate the health care consumption rates and related costs for the management of patients affected by hepatitis C virus (HCV) infection by using data from routine clinical practice

Tracers for Cardiac Imaging: Targeting the Future of Viable Myocardium

Ischemic heart disease is the leading cause of mortality worldwide. In this context, myocar- dial viability is defined as the amount of myocardium that, despite contractile dysfunction, maintains metabolic and electrical function, having the potential for functional enhancement upon revascular- ization. Recent advances have improved methods to detect myocardial viability. The current paper summarizes the pathophysiological basis of the current methods used to detect myocardial viability in light of the advancements in the development of new radiotracers for cardiac imaging