Small-animal SPECT and SPECT/CT: application in cardiovascular research

Preclinical cardiovascular research using noninvasive radionuclide and hybrid imaging systems has been extensively developed in recent years. Single photon emission computed tomography (SPECT) is based on the molecular tracer principle and is an established tool in noninvasive imaging. SPECT uses gamma cameras and collimators to form projection data that are used to estimate (dynamic) 3-D tracer distributions in vivo. Recent developments in multipinhole collimation and advanced image reconstruction have led to sub-millimetre and sub-half-millimetre resolution SPECT in rats and mice, respectively. In this article we review applications of microSPECT in cardiovascular research in which information about the function and pathology of the myocardium, vessels and neurons is obtained. We give examples on how diagnostic tracers, new therapeutic interventions, pre- and postcardiovascular event prognosis, and functional and pathophysiological heart conditions can be explored by microSPECT, using small-animal models of cardiovascular disease

Role of Imaging in Cardiomyopathies

Imaging has a central role in the diagnosis, classification, and clinical management of cardiomyopathies. While echocardiography is the first-line technique, given its wide availability and safety, advanced imaging, including cardiovascular magnetic resonance (CMR), nuclear medicine and CT, is increasingly needed to refine the diagnosis or guide therapeutic decision-making. In selected cases, such as in transthyretin-related cardiac amyloidosis or in arrhythmogenic cardiomyopathy, the demonstration of histological features of the disease can be avoided when typical findings are observed at bone-tracer scintigraphy or CMR, respectively. Findings from imaging techniques should always be integrated with data from the clinical, electrocardiographic, biomarker, genetic and functional evaluation to pursue an individualised approach to patients with cardiomyopathy

Multimodality imaging in ischemic heart disease, from prevention to outcome

The diversity in medicine and the scope of both non-invasive and invasive diagnostic instruments and treatments for ischemic heart disease have grown exponentially the last few decades. The objective of this thesis was to establish the value of different imaging techniques and treatments targeting different stages of ischemic heart disease. The results reported have demonstrated that multimodality imaging is of high relevance in patients with ischemic heart disease, facilitating the decision-making process in different groups of patients and allowing medical and (non-)invasive treatments to be better tailored to individual cases from prevention to treatment while potentially improving prognoses.LUMC / Geneeskunde Repositoriu

New targets in cardiovascular imaging

Nieuwe aanknopingspunten voor evaluatie aderverkalking Atherosclerose, in de volksmond beter bekend als aderverkalking, is een veelvoorkomende hart- en vaatziekte. De ziekte heeft een gecompliceerd en langzaam verloop. In de loop van jaren wordt een vetachtige stof (‘plaque’) afgezet in de wand van slagaders. De bloedvaten worden daardoor nauwer. Wanneer de plaque loslaat, kan deze complicaties veroorzaken, zoals een hart- of herseninfarct. Reza Golestani onderzocht hoe het moleculaire proces van aderverkalking met visuele technieken zoals PET-scans in beeld kan worden gebracht. Golestani ontwikkelde een beeldvormende techniek voor het visualiseren en meten van de moleculaire en cellulaire doelwitten die betrokken zijn bij atherosclerotische ziekten. Hij deed dat onder andere door diermodellen van de ziekte te onderzoeken en stukjes verwijderde plaque uit de halsslagaders. De promovendus concludeert dat zijn onderzoek veelbelovende doelen heeft geïdentificeerd om de ziekte van buitenaf in beeld te brengen. Op basis van deze nieuwe inzichten, die nog preklinisch van aard zijn, moet het in de toekomst makkelijker worden om patiënten in verschillende risicogroepen in te delen of om nieuwe medicijnen te ontwikkelen die de progressie van de ziekte moeten stoppen

A clinicopathological investigation of brainstem nuclei in Lewy body dementia

Introduction: Lewy Body Dementias (LBD) - Dementia with Lewy Bodies (DLB) and Parkinson’s Disease Dementia (PDD) - are clinical diagnoses based on the one-year rule and varied symptom onset. Previously, degeneration of the locus coeruleus (LC) and dorsal raphe nucleus (DRN) in LBD has been well established. However, the precise relationship between underlying neuropathology and clinical presentation remains to be determined. Methods: Immunohistochemical and image analysis techniques have been performed to examine neuronal loss and protein pathologies in the noradrenergic and serotonergic systems of 20 PD, 20 PD-MCI, 20 PDD, 20 DLB cases and 20 controls. RNAscope technology was used to decipher the role of cell-surface receptors in LBD pathophysiology. Possible associations between administration of pharmacological agents with LBD pathology and disease duration was also examined. Results: The hippocampus, thalamus and cingulate cortex - crucial components of the Papez circuit - were most affected by the proteinopathies, particularly deposition that correlated with the onset of some DLB symptomatology and non-motor symptoms. LC noradrenergic neurons were reduced in LBD compared to PD. The 5-HT2A receptor seemed to be more abundant than the α2A-adrenergic receptor (AR) and serotonin transporter (SERT) in the frontal cortex of a PD patient than a PDD or DLB patient. Conclusion: LBD phenotypes may be differentiated through their limbic involvement in the Papez circuit, where α-syn accumulation may contribute to non-motor symptoms. The behaviour of each protein type may be extremely heterogenous within each region of the noradrenergic and serotonergic systems, such that it correlates with the onset of different symptoms. There may be lower expression of receptors in LBD than PD patients, perhaps due to end-stage disease and more widespread degeneration. Hence, this study may have provided further insights into LBD pathophysiology and possibly assist clinical trials in future therapeutic interventions.Open Acces

American Thyroid Association Guide to Investigating Thyroid Hormone Economy and Action in Rodent and Cell Models

Background: An in-depth understanding of the fundamental principles that regulate thyroid hormone homeostasis is critical for the development of new diagnostic and treatment ap-proaches for patients with thyroid disease. Summary: Important clinical practices in use today for the treatment of patients with hypothy-roidism, hyperthyroidism, or thyroid cancer, are the result of laboratory discoveries made by scientists investigating the most basic aspects of thyroid structure and molecular biology. In this document, a panel of experts commissioned by the American Thyroid Association makes a se-ries of recommendations related to the study of thyroid hormone economy and action. These recommendations are intended to promote standardization of study design, which should in turn increase the comparability and reproducibility of experimental findings. Conclusions: It is expected that adherence to these recommendations by investigators in the field will facilitate progress towards a better understanding of the thyroid gland and thyroid hormone dependent processes

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias

2019 HRS/EHRA/APHRS/LAHRS expert consensus statement on catheter ablation of ventricular arrhythmias

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias