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irculatory support.The heart is a complex multi-scale system composed of components integrated at the subcellular, cellular, tissue and organ levels. The myocytes, the contractile elements of the heart, form a complex three-dimensional (3D) network which enables propagation of the electrical signal that triggers the contraction to efficiently pump blood towards the whole body. Cardiovascular diseases (CVDs), a major cause of mortality in developed countries, often lead to cardiovascular remodeling affecting cardiac structure and function at all scales, from myocytes and their surrounding collagen matrix to the 3D organization of the whole heart. As yet, there is no consensus as to how the myocytes are arranged and packed within their connective tissue matrix, nor how best to image them at multiple scales. Cardiovascular imaging is routinely used to investigate cardiac structure and function as well as for the evaluation of cardiac remodeling in CVDs. For a complete understanding of the relationship between structural remodelingew, we provide an overview of available and emerging cardiovascular imaging techniques for assessing myocardial architecture ex vivo and discuss their utility in being able to quantify cardiac remodeling, in CVDs, from myocyte to whole organ.Reverse Potts shunt is a palliative procedure aimed at decompressing the pressure-overloaded right ventricle in severe pulmonary hypertension (PH). We, herein, report the first case of an interventional creation of an "endogenous" reverse Potts shunt by stenting a pre-existing small but patent ductus arteriosus (PDA) in a 2 months old female infant with severe, supra-systemic PH, associated with a novel combination of a compound heterozygous ABCA3 mutation and additional heterozygous genetic variants of surfactant protein B (SFTPB) and C (SFTPC). The aforementioned combination of human genetic mutations has not been described before in viable infants, children or adults. The catheter intervention was performed via percutaneous femoral arterial access and was well-tolerated. Subsequently, the infant improved by means of clinical status, echocardiographic systolic right ventricular (RV) function, and serum NT-proBNP levels as biomarker of right atrial and RV pressure load. In conclusion, this single case report suggests that interventional stenting of a pre-existing PDA to create an "endogenous" reverse Potts shunt is feasible and efficacious in infants less than 3 months old with severe PH and impending RV failure associated with developmental lung disease.Prenatal closure of the ductus arteriosus (DA) can lead to cardiovascular dysfunction resulting in pulmonary hypertension (PH), progressive right heart failure, fetal hydrops, and fetal or neonatal demise. Supportive therapies-including mechanical ventilation, oxygen, and nitric oxide (NO)-have been employed with variable success among infants born full term, but there is no widely accepted management of prenatal closure of the DA, particularly for preterm infants. We present the case of an infant born at 31 weeks' gestation with right ventricular (RV) dysfunction and PH due to prenatal ductal closure, who was successfully treated with milrinone, resulting in full recovery of cardiac function. Prenatal ductal closure is rare, particularly under 32 weeks gestation, but should be suspected in cases of postnatal hypoxemia in the absence of significant lung disease or structural heart disease. Milrinone may be considered as a therapeutic agent to treat both PH and RV dysfunction in preterm infants status post in utero closure of the DA.Bronchopulmonary dysplasia (BPD) is a combined pulmonary vascular and parenchymal disease, representing the most common cause of chronic lung disease (CLD) in infancy. Pulmonary hypertension (PH) is frequently associated with BPD and-if persistent-substantially increases mortality. We report on a 4-month-old, former preterm infant with BPD, severe PH and right heart failure who greatly and rapidly improved clinical status and right ventricular (RV) function by means of blood biomarkers [N-terminal prohormone of brain natriuretic peptide (NT-pro-BNP), cardiac troponin T] and transthoracic echocardiography, following the addition of spironolactone and hydrochlorothiazide to the treatment regimen.<br /><br /> Macitentan, a dual endothelin receptor antagonist (ERA), was approved in 2014 for the treatment of adults with idiopathic pulmonary arterial hypertension (PAH). Once-per-day dosing and low potential hepatic toxicity make macitentan an appealing therapeutic option for children with PAH, but reports on its use in pediatric patients are still lacking.<br /><br /> Prospective observational study of 18 children [10 male; median age 8.5, minimum (min.) 0.6, maximum (max.) 16.8 years] with pulmonary hypertension (PH). Four of these 18 patients were treatment-naïve and started on a de novo macitentan therapy. [https://www.selleckchem.com/products/2-6-dihydroxypurine.html selleck chemicals llc] The remaining 14/18 children were already on a PH-targeted pharmacotherapy (sildenafil or bosentan as monotherapy or in combination). Nine children who were on bosentan were switched to macitentan. We analyzed the 6-minute walking distance (6MWD), NYHA functional class (FC)/modified ROSS score, invasive hemodynamics, echocardiographic variables and the biomarker N-terminal pro-brain natriuretic peptide (NT-proBNP).<br /><br /> Thd and was associated with improvements in invasive hemodynamics, longitudinal systolic RV function (TAPSE) and serum NT-proBNP values.<br /><br />This is the first prospective study of macitentan pharmacotherapy in infants and children with PH less then 12 years of age. Except in one patient, macitentan treatment was well tolerated and was associated with improvements in invasive hemodynamics, longitudinal systolic RV function (TAPSE) and serum NT-proBNP values.Right heart dysfunction and failure is the principal determinant of adverse outcomes in patients with pulmonary arterial hypertension (PAH). In addition to right ventricular (RV) dysfunction, systemic congestion, increased afterload and impaired myocardial contractility play an important role in the pathophysiology of RV failure. The behavior of the RV in response to the hemodynamic overload is primarily modulated by the ventricular interaction and its coupling to the pulmonary circulation. The presentation can be acute with hemodynamic instability and shock or chronic producing symptoms of systemic venous congestion and low cardiac output. The prognostic factors associated with poor outcomes in hospitalized patients include systemic hypotension, hyponatremia, severe tricuspid insufficiency, inotropic support use and the presence of pericardial effusion. Effective therapeutic management strategies involve identification and effective treatment of the triggering factors, improving cardiopulmonary hemodynamics by optimization of volume to improve diastolic ventricular interactions, improving contractility by use of inotropes, and reducing afterload by use of drugs targeting pulmonary circulation. The medical therapies approved for PAH act primarily on the pulmonary vasculature with secondary effects on the right ventricle. Mechanical circulatory support as a bridge to transplantation has also gained traction in medically refractory cases. The current review was undertaken to summarize recent insights into the evaluation and treatment of RV dysfunction and failure attributable to PAH.Sudden cardiac death (SCD), or sudden loss of life-sustaining systemic and cerebral perfusion, is most often due to left ventricular (LV) dysfunction secondary to ischemic or structural cardiac disease or channelopathies. Degeneration of sinus rhythm into ventricular tachycardia and ultimately ventricular fibrillation is the final common pathway for most heart failure patients. Right ventricular (RV) dysfunction is recognized as an independent contributor to worsening heart failure. There is emerging evidence that RV dysfunction may also be an independent predictor of SCD. This review examines the role of RV dysfunction on modifying long term risk of SCD, and explores possible mechanisms that may underlie SCD. The RV has unique anatomy and physiology compared to the LV. Subsequently, we begin with a review of cardiac embryology, focusing on the chambers, valves, coronary arteries, and cardiac conduction system to understand the origins of RV dysfunction. Static and dynamic physiology of the RV is contrasted with that of the LV. Particular emphasis is placed on ventriculo-arterial coupling, mechanical cardiac constraint, and ventricular interdependence. The epidemiology of SCD is briefly reviewed to highlight how causes of SCD are age-specific. In turn, the age-specific causes of RV dysfunction are presented, including those which predominate in childhood and adolescence [arrhythmogenic RV dysplasia (ARVD) and hypertrophic cardiomyopathy (HCM)] and older adulthood (cardiac ischemia, chronic congestive heart failure and post-capillary pulmonary hypertension, and pulmonary hypertension). There is a clear need for additional studies on the independent contribution of RV dysfunction to overall functional capacity, SCD-associated mortality, and non-SCD-associated mortality. Discovery would be aided by the development of prospective cohorts with excellent RV phenotyping, coupled with deeper biologic measurements linking mechanisms to clinically relevant outcomes.Right ventricular (RV) function is important for clinical status and outcomes in children and adults with congenital heart disease (CHD). In the normal RV, longitudinal systolic function is the major contributor to global RV systolic function. A variety of factors contribute to RV failure including increased pressure- or volume-loading, electromechanical dyssynchrony, increased myocardial fibrosis, abnormal coronary perfusion, restricted filling capacity and adverse interactions between left ventricle (LV) and RV. We discuss the different imaging techniques both at rest and during exercise to define and detect RV failure. We identify the most important biomarkers for risk stratification in RV dysfunction, including abnormal NYHA class, decreased exercise capacity, low blood pressure, and increased levels of NTproBNP, troponin T, galectin-3 and growth differentiation factor 15. In adults with CHD (ACHD), fragmented QRS is independently associated with heart failure (HF) symptoms and impaired ventricular function. Furthermore, we discuss the different HF therapies in CHD but given the broad clinical spectrum of CHD, it is important to treat RV failure in a disease-specific manner and based on the specific alterations in hemodynamics. Here, we discuss how to detect and treat RV dysfunction in CHD in order to prevent or postpone RV failure.Pulmonary hypertension (PH) is a progressive disease affecting patients across the life span. The pathophysiology primarily involves the pulmonary vasculature and right ventricle (RV), but eventually affects the left ventricular (LV) function as well. Safe, accurate imaging modalities are critical for diagnosis, serial monitoring, and tailored therapy. While cardiac catheterization remains the conventional modality for establishing diagnosis and serial monitoring, noninvasive imaging has gained considerable momentum in providing accurate assessment of the entire RV-pulmonary axis. In this state-of-the-art review, we will discuss the most recent developments in echocardiography, magnetic resonance imaging, and computed tomography in PH evaluation from pediatric to adult population.