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===Overview of Developmental Anatomy of the Heart===

===Overview of Developmental Anatomy of the Heart===

The formation of the mammalian heart is a fairly complex process. The process begins when angiogenic mesodermal cells in the cardiogenic plate coalesce to form the endocardial tubes. The endocardial tubes then fuse to form a single duct, the cardiac tube. This undergoes a process of

The formation of the mammalian heart is a fairly complex process. The process begins when angiogenic mesodermal cells in the cardiogenic plate coalesce to form the endocardial tubes. The endocardial tubes then fuse to form a single duct, the cardiac tube. This undergoes a process of distension, folding and septation and a two chambered pump is formed . The simple heart seen in fish or amphibians forms via the same path but development ceases at an earlier stage.

 

 

 

The primordium of the heart forms in the cardiogenic plate located at the cranial end of the embryo. These angiogenic cells are derived from the lateral plate [http://w01.rvcwiki.wf.ulcc.ac.uk/index.php/Developmental_Biology_-_Gastrulation_-_Anatomy_%26_Physiology#Introduction Mesoderm] The Angiogenic cell clusters lie in a horseshoe shape configuration in the plate and coalesce to form two endocardial tubes. These tubes are then forced into the thoracic region due to cephalic and lateral foldings where they fuse together forming a single endocardial tube.

The tube is then subdivided into primordial heart chambers starting caudally at the inflow end: the sinus venosus, primitive atria, ventricle and bulbus cordis.

The heart tube grows rapidly forcing it to bend upon itself resulting in the bulboventricular loop. Septa begin to grow in the atria, ventricle and bulbus cordis forming right and left atria, right and left ventricles and two great vessels - the pulmonary artery and the aorta.

The processes involved in forming a simple heart, such as that in a fish, or a multi-chambered heart, as seen in oxygen-breathing vertebrates, follow similar pathways.

===Cardiac Tube Formation===

===Cardiac Tube Formation===