Cardiovascular Embryology 1 Flashcards
Outline the development of the primordial heart tube
3rd-4th week
Lateral plate splanchnic mesoderm forms cardiovascular system
Angioblastic cords canalise and coalesce into heart tubes
What type of cells collect into islands and where do they move?
Angioblastic cells form islands and move towards the midline
Why does the primordial heart form so early?
Embryo needs transportation of nutrients as it gets bigger
Describe the formation of the pericardium
Derived from intra-embryonic coelom
Parietal and fibrous - somatic mesoderm
Visceral formed from splanchnic mesoderm
How is the primordial heart orientated dorsal to the pericardial cavity?
Cranial folding of embryo
Describe the regions of the primordial heart tube?
Truncus arteriosus Bulbs cordis Ventricle Atrium Sinus venosus
What is the growth rate of the bulbus cordis and ventricle?
Faster than the rest - forming U-shaped tube called the bulboventricular loop
When does atrial and ventricular separation occur?
27th to 37th day
Separation includes two actively growing masses - what are they?
Endocardial cushion and septum formation
What does the endocardial cushion separate?
Let and right atrioventricular openings
Describe the process of atrial septation
Septum primum forms across foramen primum -then septum secundum develops across foramen secumdum
Where does the septum secundum form with respect to the septum primum
On the right
Describe ventricular septation
Muscular septum forms
Leaves IV foramen
Membranous septum closes IV foramen
Outline the partition of bulbus cordis and truncus arteriosus
Proliferation of mesenchymal cells at 5th week septates the tube - blood flow causing helication and ultimately divides into pulmonary trunk and aorta
What is the pathophysiology behind SIDS?
Abnormalities of conducting tissue in heart
