Cardiovascular Disease Flashcards
Truncus arteriosus
Embryonic structure that gives rise to ascending aorta and pulmonary trunk
Bulbus cordis
Embryonic structure that gives rise to outflow tract of R and L ventricles
Primitive atrium and primitive ventricle
Give rise to trabeculated portions of atria and ventricles
Primitive pulmonary vein
Gives rise to smooth part of left atrium
Left and right horns of sinus venosus
Left gives rise to coronary sinus
Right gives rise to smooth part of right atrium
Embryonic structures that give rise to SVC
Right common cardinal vein and right anterior cardinal vein
Cardiac looping
Starts at week 4 and establishes the right-left polarity.
Dextrocardia
Seen in Kartagener as left-right dynein is required for proper cardiac looping
Atrial septation
- Septum primum grows
- Foramen secundum forms in septum primum
- Septum secundum forms; foramen secundum maintains R to L shunt
- Septum secundum expands leaving just small opening, the foramen ovale
- Septum primum and secundum fuse to form atrial septum
- Increased LA pressure closes foramen ovale after birth
Ventricular septation
- Muscular ventricular septum forms with interventricular foramen as an opening
- Formation of membranous interventricular septum
- Endocardial cushions grow to separate atria from ventricles. Contribute to atrial septation as well as the membranous portion of the interventricular septum
Fetal erythropoiesis
Yolk sac from week 3-8
Liver from 6 weeks to birth
Spleen from 10-28 weeks
Bone marrow from 18 weeks to adult
Fetal hemoglobin
Higher O2 affinity due to less 2,3 BPG binding
Fetal circulation: umbilical vein and artery
Umbilical vein brings blood from placenta to fetus. High O2 saturation
Umbilical arteries bring blood from fetus back to placenta. Low O2 saturation
Ductus venosus
Shunts blood entering the fetus through the umbilical vein to the IVC to bypass hepatic circulation
Foramen ovale
Shunts oxygenated blood entering the RA from the IVC to LA to bypass the pulmonary circulation
Ductus arteriosus
Shunts deoxygenated blood entering the RA and then RV from the SVC from the pulmonary artery to the descending aorta. Occurs due to high fetal pumonary artery resistance which is due to the low O2 tension.
Changes in circulation at birth
Infant takes a breath which causes decreased resistance in the pulmonary vasculature, allowing blood to flow through and increasing LA pressure relative to RA pressure. This causes foramen ovale to close.
Increase in O2 and decrease in PG related to placental separation results in closure of the ductus arteriosus
Adult derivative of allantois/urachus
median umbilical ligament
Adult derivative of ductus arteriosus
ligamentum arteriosum
Adult derivative of ductus venosus
Ligamentum venosum
Adult derivative of foramen ovale
Fossa ovalis
Adult derivative of notochord
Nucleus pulposus
Adult derivative of umbilical arteries
medial umbilical ligaments
adult derivative of umbilical vein
ligamentum teres which is within the falciform ligament