Term
|
Definition
|
|
Term
The truncus arteriosus gives rise to what? |
|
Definition
Ascending aorta and pulmonary trunk |
|
|
Term
The bulbus cordis gives rise to what? |
|
Definition
Smooth parts (outflow tract) of left and right ventricles |
|
|
Term
The endocardial cushion gives rise to what? |
|
Definition
Atrial septum, membranous interventricular septum; AV and semilunar valves |
|
|
Term
The primitive atrium gives rise to what? |
|
Definition
Trabeculated part of the left and right atria |
|
|
Term
The primitive ventricle gives rise to what? |
|
Definition
Trabeculated part of left and right ventricles |
|
|
Term
The primitive pulmonary vein gives rise to what? |
|
Definition
Smooth part of left atrium |
|
|
Term
The left horn of sinus venosus gives rise to what? |
|
Definition
|
|
Term
The right horn of sinus venosus gives rise to what? |
|
Definition
Smooth part of right atrium (sinus venarum) |
|
|
Term
The right common cardinal vein and right anterior cardinal vein gives rise to what? |
|
Definition
|
|
Term
What is the first functional organ in vertebrate embryos? |
|
Definition
|
|
Term
When does the heart begin to beat spontaneously? |
|
Definition
|
|
Term
What is heart morphogenesis? |
|
Definition
The process by which a straight tube morphs into the heart. |
|
|
Term
|
Definition
When the primary heart tube loops to establish left-right polarity. |
|
|
Term
When does cardiac looping begin? |
|
Definition
Cardiac looping begins in week 4 of gestation |
|
|
Term
A defect in left-right dynein can lead to what? |
|
Definition
Dextrocardia, as seen in Kartagener syndrome (primary ciliary dyskinesia) |
|
|
Term
Left-right dynein is involved in what? |
|
Definition
|
|
Term
Describe the seven steps of atrial septation |
|
Definition
- Septum primum grows toward endocardial cushions, narrowing foramen primum.
- Foramen secundum forms in septum primum (foramen primum disappears.
- Septum secundum develops as foramen secundum maintains left-to-right shunt.
- Septum secundum expands and covers most of the foramen secundum. The residual foramen is the foramen ovale.
- Remaining portion of septum primum forms valve of foramen ovale.
- Septum secundum and septum primum fuse to form the strial septum.
- Foramen ovale usually closes soon after birth because of ↑ LA pressure.
|
|
|
Term
What is the etiology of a patent foramen ovale? |
|
Definition
Failure of septum primum and septum secundum to fuse after birth; most are left untreated. |
|
|
Term
How might a person with patent foramen ovale acquire a paradoxical emboli? |
|
Definition
Venous thromboemboli may form, travel to right atrium, through patent foramen ovale to left atrium, to left ventricle, and out to systemic circulation (carotids) |
|
|
Term
Describe the steps in ventricular septation |
|
Definition
- Muscular interventricular septum form. Openin is called interventricular foramen.
- Aorticopulmonary septum rotates and fuses with muscular ventricular septum to form membranous interventricular septum, closing interventricular foramen.
- Growth of endocardial cushions separates atria from ventricles and contributes to both atrial septation and membranous portion of the interventricular septum.
|
|
|
Term
What is the most common congenital cardiac anomaly? |
|
Definition
Ventricular septal defect |
|
|
Term
In which part of septum do VSDs usually occur? |
|
Definition
|
|
Term
|
Definition
Neural crest and endocardial cell migrations → truncal and bulbar ridges that spiral and fuse to form aorticopulmonary septum → ascending aorta and pulmonary trunk |
|
|
Term
What are conotruncal abnormalities associated with? |
|
Definition
Transposition of the great veins
Tretalogy of Fallot
Persistent truncus arteriosus |
|
|
Term
Aortic/pulmonic valves derived from what? |
|
Definition
Endocardial cushions of outlfow tract |
|
|
Term
Mitral/ tricuspid valves derived from what? |
|
Definition
Fused endocardial cushions of the AV canal |
|
|
Term
What are the types of valvular anomalies? |
|
Definition
Stenotic
Regurgitant
Atretic (tricuspid atresia)
Displaced (eg, Ebstein anomaly) |
|
|
Term
|
Definition
|
|
Term
What is the PO2 and O2 saturation of blood in the umbilical vein? What about umbilical arteries? |
|
Definition
PO2 = 30 mm Hg
O2 Sat = 80%
Umbilical arteries have low O2 sats. |
|
|
Term
Describe fetal blood flow and the 3 important shunts |
|
Definition
- Blood entering the fetus through the umbilical vein is conducted via the ductus venosus into the IVC, bypassing hepatic circulation
- Most of the highly oxygenated blood reaching heart via the IVC is directed through the foramen ovale and pumped into aorta to supply the head and body.
- Deoxygenated blood from the SVC passes through the RA → RV → Main pulmonary artery → Patent ductus arteriosus → descending aorta; shunt is due to high fetal pulmonary resistance (due partly to low O2 tension)
|
|
|
Term
How does the foramen ovale close at birth? |
|
Definition
At birth, infant takes breath; ↓ resistance in pulomnary vasculature → ↑ left atrial pressure vs. right atrial pressure; foramen ovale closes (now called fossa ovalis) |
|
|
Term
How does the ductus arteriosus close at birth? |
|
Definition
Increased in O2 (from respiration) and decrease in prostaglandins (from placental separation) leads to closure of ductus arteriosus |
|
|
Term
What meds help close PDA? |
|
Definition
|
|
Term
What helps keep PDA open? |
|
Definition
Prostaglandins E1 and E2 kEEp PDA open. |
|
|
Term
Fetal-postnatal derivatives |
|
Definition
|
|
Term
Allantois --> urachus becomes what? |
|
Definition
Median Umbilical Ligaments |
|
|
Term
Ductus arteriosus becomes what? |
|
Definition
|
|
Term
Ductus Venosus becomes what? |
|
Definition
|
|
Term
Foramen ovale become what? |
|
Definition
|
|
Term
|
Definition
|
|
Term
Umbilical arteries becomes what? |
|
Definition
Medial umbilical ligaments |
|
|
Term
Umbilical vein becomes what? |
|
Definition
Ligamentum teres hepatis (contained in falciform ligament) |
|
|