Cardiac embryo Flashcards
Paradoxical emboli
ASD, patent foramen ovale
Formed by AP septum and endocardial cushions
Membranous part of ventricular septum
Fossa ovalis
Remnant of foramen ovale
Steps in atrial septation
Septum primum grows toward enodcardial cushions –> formamen primum closes –> formen secundum formed in septum primum –> septum secundum forms –> covers most of foramen secundum –> residual foramen is foramen ovale –> remaining portion of septum primum forms valve of foramen ovale –> spetum secundum and primum fuse to form atrial septum –> foramen ovale closes after birth
Congenital rubella
PDA, pulmonary artery stenosis, septal defects
Marfan
Aortic regurg, thoracic aortic dissection/aneurysm, MVP
Umbilical arteries
Medial umbilical ligament
Ligamentum teres hepatis
Remnant of umbilical vein (contained in falciform ligament)
Bicuspid aortic valve
Turner syndrome
Aortic regurg
Marfan
Atrial septum
Fusion of septum primum and septum secundum
VSD
FAS
Where does EPO take place in a neonate?
Bone marrow; liver stops producing at birth
Why does PGE2 decrease after birth, precipitating closure of the foramen ovale?
Placental separation
Down syndrome
ASD (ostium secundum)
VSD
AV valve defect (endocardial cushion defect)
Diabetic mom
Transposition of great vessels
Why does fetal hemoglobin have a much higher affinity for oxygen?
Less avid binding of 2,3-BPG
Rx to close PDA
Indomethacin (inhibits PG-mediated patency)
Preductal coarctation of aorta
Turner syndrome
Primitive atria
Trabeculated part of atria
Pulmonary artery stenosis, PDA, septal defects
Congenital rubella
Trabeculated part of ventricles
Primitive ventricles
Transposition of great vessels
Diabetic mom
Rx to keep patent forman ovale
PGE2
SVC
Right common cardinal vein and left anterior cardinal vein
Steps in ventricular septation
Muscular septum forms –> creates interventricular septum –> AP septum forms and creates membranous portion of interventricular septum –> endocardial cushions separate ventricles from atria and contribute to membranous part of interventricular foramen and atrial septum
Forms valves
Endocardial cushions
Right horn on sinus venosus
Smooth part of right atrium
Separates atria and ventricles
Endocardial cushion
Turner syndrome
Bicuspid aortic valve, preductal coarctation of aorta
Neural crest
Endocardial cushions
Fusion of septum primum and septum secundum
Atrial septum
MVP
Marfan
Smooth part of right atrium
Right horn of sinus venosus
PDA
Congenital rubella
Remnant of umbilical vein
Ligamentum teres hepatis (contained in falciform ligament)
Bicuspid aortic valve, preductal coarctation of aorta
Turner syndrome
Allantois
Median umbilical ligament/urachus
Forms membranous part of ventricular septum
Formed by AP septum and endocardial cushions
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Urachal cysts form from allanotic duct between bladder and umbilicus
5 congential anomalies causing cyanosis at birth
- Truncus arteriosus
- Transposition
- Tricuspid atresia
- Tetralogy of Fallot
- Total anomalous pulmonary venous return
Most common cause of PDA
Congenital rubella
What forms the foramen ovale?
Septum secundum covering most of foramen secundum in septum primum
Pulmonary artery stenosis
Congenital rubella
What causes patent foramen ovale?
Failure of septum primum and secundum to fuse after birth
When does infant switch from producing mostly fetal hemoglobin to mostly adult?
~6 weeks
Medial umbilical ligament
Umbilical arteries
When does infant hemoglobin proportions reach adult status?
10 months
Two mediators of foramen ovale closure
Increased O2 and decreased prostaglandin E2
Smooth (outflow) part of both ventricles
Bulbus cordis
Smooth part of left atrium
Primitive pulmonary vein
Where is the first place EPO takes place in fetus? When?
Yolk sac; 3 weeks
Right common cardinal vein + left anterior cardinal vein
SVC
Bulbus cordis
Smooth (outflow) part of both ventricles
VSD most commonly associated with:
FAS
Heart beats spontaneously by:
4th week
Tetralogy of Fallot, truncus arteriosus
22q11 syndromes
Urachus
Part of allantoic duct between bladder and umbilicus
EPO in liver
6 weeks-birth
22q11 syndromes
Truncus arteriosus, tetralogy of Fallot
Ebstein’s anomaly
Tricupsid valve leaflets displace toward apex of right ventricle while annulus is in same position
Name the three fetal shunts
Forman ovale
Ductus venosus
Ductus arteriosus
Coronary sinus
Left horn of sinus venosus
EPO in yolk sac
3-8 weeks
Formed by endocardial cushions
Septum between atria and ventricles, part of membranous interventricular septum, part of atrial septum
Acyanotic or cyanotic at birth:
VSD
Acyanotic (left-to-right shunt)
Primitive pulmonary vein
Smooth part of left atrium
Notochord
Nucleus pulposus
Fetal blood flow
Placenta –> umbilical vein –> ductus venosus –> IVC –> heart –> foramen ovale –> aorta
SVC –> RA –> RV –> pulmonary atery –> ductus arteriousus –> aorta
Median umbilical ligament
Allantois
(Urachus is part of allantoic duct between bladder and umbilicus)
MVP, aortic regurg, thoracic aortic dissection/aneurysm
Marfan
Left horn of sinus venosus
Coronary sinus
Primitive ventricles
Trabeculated part of ventricles
Nucleus pulposus
Notochord
Thoracic aortic dissection/aneurysm
Marfan
Where is the most common location of a VSD?
Membranous part of ventricular septum
EPO in bone marrow
18 weeks to adult life
ASD, VSD, endocardial cusion/AV valve defects
Down syndrome
What keeps foramen ovale open?
PGE2
Failure of septum primum and secundum to fuse after birth
Patent foramen ovale
Trabeculated part of atria
Primitive atria
EPO in spleen 10-28 weeks
Forms septum between atria and ventricles, part of membranous interventricular septum, part of atrial septum
Endocardial cushions