Arrhythmic risk stratification by cardiac magnetic resonance tissue characterization: disclosing the arrhythmic substrate within the heart muscle

Sudden cardiac death (SCD) is a pivotal health problem worldwide. The identification of subjects at increased risk of SCD is crucial for the accurate selection of candidates for implantable cardioverter defibrillator (ICD) therapy. Current strategies for arrhythmic stratification largely rely on left ventricular (LV) ejection fraction (EF), mostly measured by echocardiography, and New York Heart Association functional status for heart failure with reduced EF. For specific diseases, such as hypertrophic and arrhythmogenic cardiomyopathy, some risk scores have been proposed; however, these scores take into account some parameters that are a partial reflection of the global arrhythmic risk and show a suboptimal accuracy. Thanks to a more comprehensive evaluation, cardiac magnetic resonance (CMR) provides insights into the heart muscle (the so-called tissue characterization) identifying cardiac fibrosis as an arrhythmic substrate. Combining sequences before and after administration of contrast media and mapping techniques, CMR is able to characterize the myocardial tissue composition, shedding light on both intracellular and extracellular alterations. Over time, late gadolinium enhancement (LGE) emerged as solid prognostic marker, strongly associated with major arrhythmic events regardless of LVEF, adding incremental value over current strategy in ischemic heart disease and non-ischemic cardiomyopathies. The evidence on a potential prognostic role of mapping imaging is promising. However, mapping techniques require further investigation and standardization. Disclosing the arrhythmic substrate within the myocardium, CMR should be considered as part of a multiparametric approach to personalized arrhythmic stratificatio

Facciamo il punto: miocardio non compatto

Il miocardio non compatto \ue8 una rara patologia del muscolo cardiaco caratterizzata da una marcata ipertrabecolatura parietale dovuta all\u2019arresto del processo di maturazione miocardica durante lo sviluppo fetale. Non sono stati ancora definiti dei criteri \u201cgold standard\u201d per la diagnosi; \ue8 inoltre necessaria la differenziazione da quadri parafisiologici e da altre cardiomiopatie. Rafforzano il sospetto clinico la familiarit\ue0 per la malattia, la coesistente presenza di malattia neuromuscolare, fenomeni tromboembolici, anomalie elettrocardiografiche, aritmie ventricolari, dilatazione e disfunzione ventricolare sinistra, fibrosi alla risonanza magnetica, mutazioni patogene. Molti aspetti rimangono tuttora controversi e dovranno essere chiariti con studi multicentrici, registri e studi osservazionali

Trieste science & the city young: come crescere un cuore sano

Possiamo fare qualcosa per mantenere il nostro cuore giovane e sano? Nel contesto del progetto CURIoSA (ComUnicaRe per crescere in SAlute, finanziato dalla Regione Autonoma Friuli Venezia Giulia), viene proposto un evento con esperti del mondo della scienza e dello sport sulle tematiche che hanno risvolti sull'attuazione di misure preventive delle malattie di maggiore impatto socio-sanitario (tumori e malattie cardiovascolari). Incontro a cura di ICGEB e Università di Trieste. Intervengono: Giorgio Faganello, dirigente medico SC Cardiovascolare e Medicina dello sport Azienda Sanitaria Universitaria Integrata di Trieste, Francesco Loffredo, docente di Scienze mediche applicate Università della Campania "L. Vanvitelli" di Napoli, head of Molecular Cardiology Unity ICGEB. Conduce Serena Zacchigna, group leader Cardiovascular Biology ICGEB, docente di Biologia molecolare Università di Trieste. Special guest: il gruppo musicale "Sindrome di MA

Erratum: “Detecting Reconnection Events in Kinetic Vlasov Hybrid Simulations Using Clustering Techniques” (2021, ApJ, 908, 107)

International audienc

Detecting Reconnection Events in Kinetic Vlasov Hybrid Simulations Using Clustering Techniques

International audienceAbstract Kinetic turbulence in magnetized space plasmas has been extensively studied via in situ observations, numerical simulations, and theoretical models. In this context, a key point concerns the formation of coherent current structures and their disruption through magnetic reconnection. We present automatic techniques aimed at detecting reconnection events in a large data set of numerical simulations. We make use of clustering techniques known as K -means and DBscan (usually referred to in literature as unsupervised machine-learning approaches), and other methods based on thresholds of standard reconnection proxies. All our techniques also use a threshold on the aspect ratio of the regions selected. We test the performance of our algorithms. We propose an optimal aspect ratio to be used in the automated machine-learning algorithm: AR = 18. The performance of the unsupervised approach results in it being strongly competitive with respect to those of other methods based on thresholds of standard reconnection proxies

Cardiac Magnetic Resonance in Primary Prevention of Sudden Cardiac Death

Sudden death accounts for 400,000 deaths annually in the United States. Most sudden deaths are cardiac and are related to arrhythmias secondary to structural heart disease or primary electrical abnormalities of the heart. Implantable cardioverter defibrillator significantly improves survival in patients at increased risk of life-threatening arrhythmias, but better selection of eligible patients is required to avoid unnecessary implantation and identify those patients who may benefit most from this therapy. Left ventricular (LV) ejection fraction (EF) measured by echocardiography has been considered the most reliable parameter for long-term outcome in many cardiac diseases. However, LVEF is an inaccurate parameter for arrhythmic risk assessment as patients with normal or mildly reduced LV systolic function could experience sudden cardiac death (SCD). Among other tools for arrhythmic stratification, magnetic resonance (CMR) provides the most comprehensive cardiac evaluation including in vivo tissue characterization and significantly aids in the identification of patients at higher SCD risk. Most of the evidence are related to late gadolinium enhancement (LGE), which was proven to detect cardiac fibrosis. LGE has been reported to add incremental value for prognostic stratification and SCD prediction across a wide range of cardiac diseases, including both ischemic and nonischemic cardiomyopathies. In addition, T1, T2 mapping and extracellular volume assessment were reported to add incremental value for arrhythmic assessment despite suffering from several technical limitations. CMR should be part of a multiparametric approach for patients' evaluation, and it will play a pivotal role in prognostic stratification according to the current evidence

Three dimensional printing of an atrial septal defect: Is it multimodality imaging?

Noninvasive imaging plays a pivotal role in the diagnosis and management of congenital heart disease (CHD). Despite cardiac magnetic resonance (MRI) and computed tomography (CT) have gained particular importance, 2D transthoracic echocardiogram (TEE) and 3D trans- esophageal echocardiogram (TOE) still remain the work- houses of imaging routinely used in all and CHD patients; however 3D images could be challenging in some CHD patients and not being so informative. 3D printing tech- nology improvements have been tremendous over the last few years and several different 3D printing processes have been invented in Medicin

Echocardiographic markers of inducible myocardial ischemia at baseline evaluation preparatory to exercise stress echocardiography

13noBACKGROUND: Tissue Doppler Imaging (TDI) is a sensible and feasible method to detect longitudinal left ventricular (LV) systolic dysfunction (LVSD) in patients with diabetes mellitus, hypertension or ischemic heart disease. In this study, we hypothesized that longitudinal LVSD assessed by TDI predicted inducible myocardial ischemia independently of other echocardiographic variables (assessed as coexisting potential markers) in patients at increased cardiovascular (CV) risk. METHODS: Two hundred one patients at high CV risk defined according to the ESC Guidelines 2012 underwent exercise stress echocardiography (ExSEcho) for primary prevention. Echocardiographic parameters were measured at rest and peak exercise. RESULTS: ExSEcho classified 168 (83.6 %) patients as non-ischemic and 33 (16,4 %) as ischemic. Baseline clinical characteristics were similar between the groups, but ischemic had higher blood pressure, received more frequently beta-blockers and antiplatelet agents than non-ischemic patients. The former had greater LV size, lower relative wall thickness and higher left atrial systolic force (LASF) than the latter. LV systolic longitudinal function (measure as peak S') was significantly lower in ischemic than non-ischemic patients (8.7 ± 2.1 vs 9.7 ± 2.7 cm/sec, p = 0.001). The factors independently related to myocardial ischemia at multivariate logistic analysis were: lower peak S', higher LV circumferential end-systolic stress and LASF. CONCLUSIONS: In asymptomatic patients at increased risk for adverse CV events baseline longitudinal LVSD together with higher LV circumferential end-systolic stress and LASF were the factors associated with myocardial ischemia induced by ExSEcho. The assessment of these factors at standard echocardiography might help the physicians for improving the risk stratification among these patients for ExSEcho.openopenCherubini, Antonella; Cioffi, Giovanni; Mazzone, Carmine; Faganello, Giorgio; Barbati, Giulia; Tarantini, Luigi; Russo, Giulia; Stefenelli, Carlo; Humar, Franco; Grande, Eliana; Fisicaro, Maurizio; Pandullo, Claudio; Di Lenarda, AndreaCherubini, Antonella; Cioffi, Giovanni; Mazzone, Carmine; Faganello, Giorgio; Barbati, Giulia; Tarantini, Luigi; Russo, Giulia; Stefenelli, Carlo; Humar, Franco; Grande, Eliana; Fisicaro, Maurizio; Pandullo, Claudio; DI LENARDA, Andre

Does renal function influence the prognostic impact of type 2 diabetes mellitus in patients with chronic heart failure and left ventricular dysfunction?

Hypothesis: Type 2 diabetes mellitus (T2DM) and chronic heart failure (CHF) are associated with renal dysfunction. We tested the hypothesis that the degree of renal dysfunction influences the negative impact on the outcome of T2DM in patients with CHF and reduced left ventricular ejection fraction (LVEF). Methods: From November 1, 2009 to December 31, 2012, the “Trieste Registry of CV Diseases” enrolled 19,589 patients. Those with diagnosis of CHF and reduced LVEF were analyzed. The primary end-point was all-cause mortality. Results: 554 patients were selected (73 ± 10 years old, 32% females), 192 had T2DM (35%). During follow-up (23 ± 11 months), all-cause death occurred in 57 patients (30%) who had T2DM and in 58 (16%, p < 0.001) who had not; T2DM was associated with an increased risk of death (adjusted HR 2.55 [95% CI 1.02-6.36], p = 0.04). The prognostic impact of T2DM was lost when patients were selected according to renal function: adjusted HR 1.44 [0.21-9.93], p = 0.71, in patients with normal renal function, defined as estimated glomerular filtration rate (eGFR) >60, and adjusted HR 3.37 [0.96-11.80], p = 0.08 in patients with renal dysfunction (eGFR < 60 ml/min ∗ 1.73 m2). T2DM predicted all-cause mortality only in the subgroup with eGFR between 90 and 30 ml/min ∗ 1.73 m2 (adjusted HR 2.52 [1.01-6.30], p = 0.04). Conclusions: In patients with CHF and reduced LVEF the prognostic impact of T2DM depends on the degree of renal dysfunction. Its contribution in all-cause mortality risk prediction is limited to mild–moderate renal dysfunction subgroup, while prognostic power is lost in normal renal function and in severe renal dysfunction patients