Cardiac Development Flashcards
Which layer of the trilaminar disc gives rise to the heart?
Mesoderm
Which cells are the precursors for cardiac myocytes?
Cardiogenic cells
Where do cardiogenic cells initially arise and in what pattern?
Outside the embryo proper
In a horseshoe pattern
What do the cardiogenic cells form?
They form a pair of endocardial tubes
What has happened to these tubes by day 21?
Fusion of the tubes, enabling unidirectional pumping of blood
What happens after this fusion?
Looping of the heart
Septation
Valve development
Which gap forms between the atria and what is its function?
Foramen ovale; allows blood to bypass the lungs going straight from the right atrium to the left atrium
What is the second hole in the heart of a fetus and what is its function?
Ductus arteriosus; pulmonary artery is connected to the aorta, again bypassing the lungs
What are the four features of tetralogy of fallot?
Pulmonary stenosis (thickening) Thickened right ventricle wall Ventricular septal defect Aorta overrides the septal defect
Describe a defective transposition of blood vessels
Transposition of the great arteries (aorta originates from RV and pulmonary artery originates from LV)
Why does this cause a problem after birth?
Closing of the ductus arteriosus and the foramen ovale means that oxygenated blood ends up going to the lungs and deoxygenated blood circulates the body causing cyanosis
What is the immediate treatment for blue baby syndrome?
Administer prostaglandins to keep ductus arteriosus open
Surgical opening between atria
What is the long term treatment for blue baby syndrome?
Switching of the vessels to restore normal blood flow
