Embryology heart cardiac

The ratites are a distinctive clade of flightless birds, typified by the emu and ostrich that have acquired a range of unique anatomical characteristics since diverging from basal Aves at least 100 million years ago. The emu possesses a vestigial wing with a single digit and greatly reduced forelimb musculature. However, the embryological basis of wing reduction and other anatomical changes associated with loss of flight are unclear. Here we report a previously unknown co-option of the cardiac transcription factor Nkx2...

This chapter will discuss the role of cardiac fibroblasts as a target of various immunological inputs as well as an immunomodulatory hub of the heart through interaction with immune cell types and chemokine or cytokine signaling. While the purpose of this chapter is to explore the immunomodulatory properties of cardiac fibroblasts, it is important to note that cardiac fibroblasts are not a homogeneous cell type, but have a unique embryological origin and molecular identity. Specific properties of cardiac fibroblasts may influence the way they interact with the heart microenvironment to promote healthy homeostatic function or respond to pathological insults...

Atrioventricular septal defect results from a failure of normal endocardial cushion fusion during embryologic cardiac development. This developmental aberration results in defects in the atrial and/or ventricular septum and malformation of the atrioventricular valves. The pathophysiology of atrioventricular septal defect is variable, and ranges from mild left to right shunting similar to a simple atrial septal defect to complex single-ventricle heart disease. This review focuses on the spectrum of atrioventricular septal defect from partial to complete, without associated cardiac defects...

Clinical data and basic research indicate that the structural and functional alterations that characterize the evolution of cardiac disease towards heart failure may be, at least in part, reversed. This paradigm shift is due to the accumulation of evidence indicating that, in peculiar settings, cardiomyocytes may be replenished. Moving from the consideration that cardiomyocytes are rapidly withdrawn from the cell cycle after birth, independent laboratories have tested the hypothesis that cardiac resident stem/progenitor cells resided in mammalian hearts and were important for myocardial repair...

Ebstein anomaly is a rare form of congenital heart disease with a uniquely high prevalence of arrhythmias. The most prevalent arrhythmia mechanisms are intrinsic to the underlying embryologic defects and may manifest at any stage. Current electrophysiological and surgical strategies are well equipped to address these arrhythmia mechanisms, yet despite available technology and a robust understanding of the mechanisms, these cases remain challenging. Surgical techniques that render arrhythmia substrates unreachable mandate comprehensive presurgical electrophysiological assessment and potential ablation...

Despite advances in cardiovascular biology and medical therapy, heart disorders are the leading cause of death worldwide. Cell-based regenerative therapies become a promising treatment for patients affected by heart failure, but also underline the need for reproducible results in preclinical and clinical studies for safety and efficacy. Enthusiasm has been tempered by poor engraftment, survival and differentiation of the injected adult stem cells. The crucial challenge is identification and selection of the most suitable stem cell type for cardiac regenerative medicine...

Cardiac lipomas are rare and usually present as benign, encapsulated masses outside the heart; however, they can also be found within the atria. No single theory-including molecular genetic mutation-adequately explains why this occurs. Extensive career experience and broadened knowledge in embryology and cardiac physiology have helped us to develop a hypothesis based on invagination of extracardiac tumors. This report describes a vexing case of a giant right atrial lipoma, from 1985, in which the diagnosis was made incidentally during management of a patient's acute limb ischemia...

The life-long story of the heart starts concomitantly with primary differentiation events occurring in multipotent progenitors located in the so-called heart tube. This initially tubular structure starts a looping process, which leads to formation of the final four-chambered heart with a primary contribution of geometric and position-associated cell sensing. While this establishes the correct patterning of the final cardiac structure, it also provides feedbacks to fundamental cellular machineries controlling proliferation and differentiation, thus ensuring a coordinated restriction of cell growth and a myocyte terminal differentiation...

It is customary, at the current time, to consider many, if not most, of the lesions involving the ventricular outflow tract in terms of conotruncal malformations. This reflects the introduction, in the early 1940s, of the terms conus and truncus to describe the components of the developing outflow tract. The definitive outflow tracts in the postnatal heart, however, possess three, rather than two, components. These are the intrapericardial arterial trunks, the arterial roots, and the subvalvar ventricular outflow tracts...

The Chiari network is an embryological remnant found in the right atrium, mostly without any significant pathophysiological consequences. However, several cardiac associations are reported in the literature including supraventricular tachyarrhythmias. We present a case of a 96-year-old body donor with a stroke episode and intermittent atrial fibrillations. The dissection of the heart revealed the presence of an immense Chiari network with a large central thrombus. The role of a Chiari network in the pathogenesis of stroke and pulmonary embolism is discussed...

Congenital heart disease is diagnosed in 0.4% to 5% of live births and presents unique challenges to the pediatric anesthesiologist. Furthermore, advances in surgical management have led to improved survival of those patients, and many adult anesthesiologists now frequently take care of adolescents and adults who have previously undergone surgery to correct or palliate congenital heart lesions. Knowledge of abnormal heart development on the molecular and genetic level extends and improves the anesthesiologist's understanding of congenital heart disease...

A wide range of ion channels, transporters, signaling pathways and tissue structure at a microscopic and macroscopic scale regulate the electrophysiological activity of the heart. Each region of the heart has optimised these properties based on its specific role during the cardiac cycle, leading to well-established differences in electrophysiology, Ca(2+) handling and tissue structure between atria and ventricles and between different layers of the ventricular wall. Similarly, the right ventricle (RV) and left ventricle (LV) have different embryological, structural, metabolic and electrophysiological features, but whether interventricular differences promote differential remodeling leading to arrhythmias is not well understood...

Congenital cardiovascular malformations are the most common birth defects, with a complex multifactorial etiology. Genetic factors play an important role, illuminated by numerous cytogenetically visible abnormalities, as well as submicroscopic genomic imbalances affecting critical genomic regions in the affected individuals. Study of rare families with Mendelian forms, as well as emerging next-generation sequencing technologies have uncovered a multitude of genes relevant for human congenital cardiac diseases...

Hypertrophic cardiomyopathy (HCM) is caused by mutations in sarcomeric proteins, the commonest being MYBPC3 encoding myosin-binding protein C. It is characterised by left ventricular hypertrophy but there is an important pre-hypertrophic phenotype with features including crypts, abnormal mitral leaflets and trabeculae. We investigated these during mouse cardiac development using high-resolution episcopic microscopy. In embryonic hearts from wildtype, homozygous (HO) and heterozygous (HET) Mybpc3-targeted knock-out (KO) mice we show that crypts (one or two) are a normal part of wildtype development but they almost all resolve by birth...

BACKGROUND: Maternal diabetes mellitus is associated with an increased risk of offspring congenital heart defects (CHD); however, the causal mechanism is poorly understood. We further investigated this association in a Danish nationwide cohort. METHODS AND RESULTS: In a national cohort study, we identified 2 025 727 persons born from 1978 to 2011; among them were 7296 (0.36%) persons exposed to maternal pregestational diabetes mellitus. Pregestational diabetes mellitus was identified by using the National Patient Register and individual-level information on all prescriptions filled in Danish pharmacies...

Cardiac transcription factors orchestrate the complex cellular and molecular events required to produce a functioning heart. Misregulation of the cardiac transcription program leads to embryonic developmental defects and is associated with human congenital heart diseases. Recent studies have expanded our understanding of the regulation of cardiac gene expression at an additional layer, involving the coordination of epigenetic and transcriptional regulators. In this review, we highlight and discuss discoveries made possible by the genetic and embryological tools available in the zebrafish model organism, with a focus on the novel functions of cardiac transcription factors and epigenetic and transcriptional regulatory proteins during cardiogenesis...

Congenital heart defects are the most common birth defects in humans, and those that affect the proper alignment of the outflow tracts and septation of the ventricles are a highly significant cause of morbidity and mortality in infants. A late differentiating population of cardiac progenitors, referred to as the anterior second heart field (AHF), gives rise to the outflow tract and the majority of the right ventricle and provides an embryological context for understanding cardiac outflow tract alignment and membranous ventricular septal defects...

At present, there is significant interest in the morphology of the coronary arteries, not least due to the increasingly well-recognised association between anomalous origin of the arteries and sudden cardiac death. Much has also been learnt over the last decade regarding the embryology of the arteries. In this review, therefore, we provide a brief introduction into the recent findings regarding their development. In particular, we emphasise that new evidence, derived using the developing murine heart, points to the arterial stems growing out from the adjacent sinuses of the aortic root, rather than the arteries growing in, as is currently assumed...

UNLABELLED: In the last decade, cardiac computed tomography (CT) has gained mainstream acceptance for the noninvasive exclusion of significant coronary disease in a selected population. Improvements in electrocardiogram (ECG)-triggered imaging techniques also allow, by extension, a proper evaluation of the complete heart anatomy. Given the increasing worldwide clinical implementation of cardiac CT for coronary artery evaluation, radiologists can, incidentally, be confronted with unfamiliar and previously unsuspected non-coronary cardiac pathologies, including congenital morphological defects...

Ebstein's anomaly of the tricuspid valve (TV) refers to an embryological derangement of TV formation causing tethering of the septal and posterior leaflets of the valve to the underlying myocardium and apical displacement of the effective valve annulus, resulting in significant TV insufficiency and dilation of the right heart structures. The pathological abnormalities of the valve can vary significantly, resulting in a wide range of clinical presentations. Fetal diagnosis and neonatal presentations of the disease are typically the most severe and are associated with the highest mortality rates...