Cardiovascular-Embryology Flashcards
Embryonic Structure: Truncus arteriosus (TA)
Gives rise to?
Ascending aorta and pulmonary trunk
Embryonic Structure: Bulbus cordis
Gives rise to?
Smooth parts (outflow tracts) of left and right ventricles
Embryonic Structure: Primitive atria
Gives rise to?
Trabeculated part of left and right atria
Embryonic Structure: Primitive ventricle
Gives rise to?
Trabeculated part of left and right ventricles
Embryonic Structure: Primitive pulmonary vein
Gives rise to?
Smoot part of left atrium
Embryonic Structure: Left horn of sinus venosus (SV)
Gives rise to?
Coronary sinus
Embryonic Structure: Right horn of SV
Gives rise to?
Smooth part of right atrium
Right common cardinal vein and right anterior cardinal vein?
Gives rise to?
SVC
Defect in left-right dynein (involved in L/R asymmetry) can lead to…
Dextrocardia (as seen in Kartagener syndrome (primary ciliary dyskinesia))
Ventricle septation of chambers formation
1) Muscular ventricular septum forms. Opening is called IV foramen
2) AP septum rotates and fuses with muscular ventricular septum to form membranous interventricular septum, closing interventricular foramen
Growth of endocardial cushions contributes to…
1) Seperation of Atria from ventricles
2) Part of atrial septum and membranous portion of ventricular septum
VSD most commonly occurs in the…
membranous septum
Outflow tract formation
Truncus arteriosus rotates; neural cres and endocardial cell migrations from hindbrain to AP trunk –> cells invade truncal and bulbar ridges that spiral and fuse to form AP septum–> dividing AP trunk into ascending aorta and pulmonary trunk
Aortic/Pulmonary valve embryonic origin?
Endocardial cushions of outflow tract
Mitral/Tricuspid valve embryonic origin?
Fused endocardial cushion of the AV canal
Atria septation of chambers formation
1) Septum primum grows toward endocardial cushion, narrowing foramen primum
2) foramen secundum forms in spetum primum (septum primum disappears)
3) Septum secundum forms resulting in foramen secundum maintaining right to left shunt
4) Septum secundum expands and covers most of foramen secundum. Residual foramen is foramen ovale
5) Remaining portaion of septum primum forms valve of foramen ovale
6) Septum secundum and septum primum fuse to form atrial septum
Patent formamen ovale
Failure of spetum primum and suptum secundum to fuse after birth
Foramen ovale closes after birth due to
Increase in LA pressure with first breath
Fetal erythropoiesis occurs in
Yolk sac (3-8 weeks) Liver (6 weeks-Birth) Spleen (10-28 weeks) Blood (18 weeks to adult) "young liver synthesizes blood"
3 important shunts in fetal circulation?
1) Ductus venosus (bypassing hepatic circulation to directly drain into IVC)
2) Foramen ovale (oxygenated blood from right atrium to left atrium so it can enter left ventricle and be pumped out to head and body from the aorta)
3) Ductus arteriosus (deoxygenated blood from SVC eventually to descending aorta)
Fetal: Umbilical vein
Postnatal derivative?
Ligamentum teres hepatis (round ligament) contained in falciform ligament
Fetal: Umbilical arteries
Postnatal derivative?
MediaL umbilical arteries
Fetal: Ductus arteriosus
Postnatal derivative?
Ligamentum arteriosum
Fetal: Ductus venosus
Postnatal derivative?
Ligamentum venosum
