Nuclear cardiology at the door of a new era: better to save mSv or to reduce imaging time?

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Myocardial blood flow regulation in infarcted patients with stress-induced normalization of negative T waves

The correlation of stress-induced normalization of negative T waves (NTW) with regional myocardial blood flow (MBF) regulation and tissue viability remains still dented

Altered adipocyte differentiation and unbalanced autophagy in type 2 Familial Partial Lipodystrophy: an in vitro and in vivo study of adipose tissue browning

Type-2 Familial Partial Lipodystrophy is caused by LMNA mutations. Patients gradually lose subcutaneous fat from the limbs, while they accumulate adipose tissue in the face and neck. Several studies have demonstrated that autophagy is involved in the regulation of adipocyte differentiation and the maintenance of the balance between white and brown adipose tissue. We identified deregulation of autophagy in laminopathic preadipocytes before induction of differentiation. Moreover, in differentiating white adipocyte precursors, we observed impairment of large lipid droplet formation, altered regulation of adipose tissue genes, and expression of the brown adipose tissue marker UCP1. Conversely, in lipodystrophic brown adipocyte precursors induced to differentiate, we noticed activation of autophagy, formation of enlarged lipid droplets typical of white adipocytes, and dysregulation of brown adipose tissue genes. In agreement with these in vitro results indicating conversion of FPLD2 brown preadipocytes toward the white lineage, adipose tissue from FPLD2 patient neck, an area of brown adipogenesis, showed a white phenotype reminiscent of its brown origin. Moreover, in vivo morpho-functional evaluation of fat depots in the neck area of three FPLD2 patients by PET/CT analysis with cold stimulation showed the absence of brown adipose tissue activity. These findings highlight a new pathogenetic mechanism leading to improper fat distribution in lamin A-linked lipodystrophies and show that both impaired white adipocyte turnover and failure of adipose tissue browning contribute to disease.We thank FPLD2 patients for donating biological samples. We thank the Italian Network for Laminopathies and the European Consortium of Lipodystrophies (ECLip) for support and helpful discussion. We thank Aurelio Valmori for the technical support. The studies were supported by Rizzoli Orthopedic Institute “5 per mille” 2014 project to MC, AIProSaB project 2016 and Fondazione Del Monte di Bologna e Ravenna grant 2015–2016 “New pharmacological approaches in bone laminopathies based on the use of antibodies neutralizing TGF beta 2” to GL. GL is also supported by PRIN MIUR project 2015FBNB5Y.S

Nuclear medicine techniques for the diagnosis of cardiac amyloidosis: the state of the art

Amyloidosis is a disease characterized by the deposition of amorphous protein material in the extracellular space which leads to progressive dysfunction of the affected organ. The forms of amyloidosis that most frequently involve the heart are transthyretin amyloidosis (ATTR) and immunoglobulin light chain amyloidosis (AL). Nuclear medicine offers numerous imaging techniques for the evaluation of patients with cardiac amyloidosis, and in the last decade osteophilic tracer scintigraphy has assumed a fundamental role in the diagnostic process of this disease. New PET radiopharmaceuticals for the detection of amyloid deposits are proving very effective in diagnosing the presence of AL amyloidosis and could soon allow a differential diagnosis without the need for invasive and potentially risky techniques such as endomyocardial biopsy

Stress-induced alteration of left ventricular eccentricity: An additional marker of multivessel CAD

BackgroundAbnormal left ventricular (LV) eccentricity index (EI) is a marker of adverse cardiac remodeling. However, the interaction between stress-induced alterations of EI and major cardiac parameters has not been explored. We sought to evaluate the relationship between LV EI and coronary artery disease (CAD) burden in patients submitted to myocardial perfusion imaging (MPI).Methods and resultsThree-hundred and forty-three patients underwent MPI and coronary angiography. LV ejection fraction (EF) and EI were computed from gated stress images as measures of stress-induced functional impairment.One-hundred and thirty-six (40%), 122 (35%), and 85 (25%) patients had normal coronary arteries, single-vessel CAD, and multivessel CAD, respectively. Post-stress EI was lower in patients with multivessel CAD than in those with normal coronary arteries and single-vessel CAD (P=0.001). This relationship was confirmed only in patients undergoing exercise stress test, where a lower post-stress EI predicted the presence of multivessel CAD (P=0.039).ConclusionsPost-stress alterations of LV EI on MPI may unmask the presence of multivessel CAD

Evaluation data about accuracy of cadmium-zinc-telluride imaging in detecting single and multivessel coronary artery disease: Focus on gender differences

The data presented in this article are related to the research article entitled: “Accuracy of cadmium-zinc-telluride imaging in detecting single and multivessel coronary artery disease: is there any gender difference?” (Gimelli et al., 2018).We evaluated gender-related differences in diagnostic accuracy of cadmium-zinc-telluride (CZT) myocardial perfusion imaging (MPI) in detecting single- and multi-vessel coronary artery disease (CAD). We included 1161 consecutive patients with known or suspected coronary artery disease (228, 25% women and 873, 75% men) who had been referred to our laboratory for stress–rest myocardial perfusion imaging (single-day stress–rest low-dose ultrafast protocol). All patients underwent coronary angiography within 30 days; CAD was defined in the presence of a coronary stenosis >70%. Summed stress scores (SSS), summed rest scores (SRS) and summed difference scores (SDS) were obtained. Image quality was graded “good” or better in more than 90% of patients

Microvascular dysfunction in heart disease: Similar impairment of the microcirculation to different ethiopathogenic stimuli

Recent reports showed that a coronary microvascular dysfunction may impair myocardial blood flow (MBF) in various heart diseases. Whether the severity of MBF abnormalities are depending on the specific heart disease or on the underlying microvascular disorder is still unknown

Cardiac amyloidosis

Purpose: The aim of the present article was to review the recent developments in diagnosis, prognostication and management of cardiac amyloidosis. Methods: Available scientific literature on cardiac amyloidosis has been critically reviewed. Results: Different precursors cause different forms of cardiac amyloidosis with different outcomes and therapeutic options. Cardiac involvement determines not-specific symptoms and the diagnosis remains often a challenge for cardiologists. As a consequence, patients continue to present end-stage heart failure when possible effective therapeutic interventions are of limited utility. Conclusions: Advances in cardiac biomarkers assessment, echocardiography, cardiac magnetic resonance and nuclear molecular imaging have improved the ability of cardiologists in the recognition and prognostic stratification of this not so rare, not so untreatable cardiac disease