Embryological development of CVS Flashcards
When does the CVS start to develop in the embryo?
Approx 4 weeks into development- when the placenta can no longer meet the needs of the embryo
What first forms in the CVS development?
Primitive heart tube
What is gastrulation?
An early stage in embryonic development where the single layered cells of the blastula reorganise into multiple layers to form a gastrula. The layers are the ectoderm, mesoderm and endoderm.
What part of the body develop from the ectoderm?
Skin, nervous system, neural crest- contributes to cardiac outflow and coronary arteries
What parts of the body develop from the mesoderm?
All muscle types, most of the cardiovascular system, kidneys, blood
What parts of the body develop from the endoderm?
Gastrointestinal tract including liver and pancreas (but not smooth muscle), endocrine organs
What area of the human heart develops from the first heart field?
Left ventricle
What area of the human heart develops from the second heart field?
Outflow tract, right ventricle and atria
What are the 3 stages of cardiac formation?
Formation of the primitive tube
Cardiac looping
Cardiac septation
What tubes fuse to form the primitive heart tube?
Endocardial tubes
What day of development does the primitive heart tube form?
Day 19/ third week
What day does the heart begin to beat?
Day 22
What happens in embryological development of the heart after primitive heart tube formation?
Cardiac looping
What protein is released from the ‘node’ which aids in the leftwards angle of the heart?
Nodal
How is nodal distributed unevenly in heart development?
Cilia at the node rotate to direct more nodal to the left.
How does nodal protein have an effect on the developing tissue?
Turns on specific transcription factors that affect further development (cardiac looping) of the heart
What stage of heart development occurs after cardiac looping?
Cardiac septation
What two embryological structures give rise to the cardiac ventricles?
Bulbus cordis and the primitive ventricle
What do the endocardial cushions aid in forming?
The interventricular septum
What’s the adult remnant of the foramen ovale?
Fossa ovalis
What foetal shunt results leads to the ligamentum arteriosum?
Ductus arteriosum
What is the remnant of the umbilical vein?
The ligamentum teres
What does the ductus arteriosis connect in the foetus?
Connects the main pulmonary artery to the descending aorta (to bypass the lungs in the foetus)
What does the ductus venosum connect? And what does it bypass?
Left umbilcal vein to the inferior vena cava. Allows oxygenated blood from the placenta to bypass the liver.
Where are blood islands found in the embryo?
Yolk sac
What is vasculogenesis?
The embryological formation of blood vessels
What is angiogenesis?
The development of blood vessels from existing vessels
What is the difference between vasculogenesis and angiogenesis?
Vasculogenesis is the formation of blood vessels whereas angiogenesis is where new blood vessels form from existing vessels by ‘sprouting’
What do angioblast develop into?
Blood vessels
What embryonic cells do blood cells develop from?
Angioblasts
Does angiogenesis or vasculosgenesis occur first in embyological development?
Vasculogenesis
What does the truncus arteriosus develop into?
Ascending aorta and pulmonary trunk
What does the bulbus cordis develop into?
Right ventricle
What does the primitive ventricle develop into?
Left ventricle
What does the primitive atrium develop into?
Anterior portions of the left and right atria aswell as both auricles.
Where are the two auricles of the heart found?
Anterior surfaces in the right and left atria
What does the sinus venosus develop into?
Posterior portion of right atrium
SA node
Coronary sinus
What germ cell layer develops to form the heart (aswell as CVS and all muscle types)
Mesoderm
What primitive area develops to form the ascending aorta and pulmonary trunk?
Truncus arteriosus
What primitive area develops to form the anterior portions of both atria?
Primitive artrium
What primitive area develops to form the right ventricle?
Bulbus cordis
What primitive area develops to form the left ventricle?
Primitive ventricle
What area develops to form the coronary sulcus?
Sinus venosus
What area develops to form the SA node and posterior portion of the right atrium?
Sinus venosus
