Echo 530

  1. The heart is formed between ____ & ____ weeks of gestational age.
    3-7 weeks
  2. Week 3 (early), the heart is composed or ______ endocardial ________.
    • 2
    • tubes
  3. The cardiac tube consists of ____________ ____________ with core cardiac ____________.
    • myocardial mantle
    • jelly
  4. Endocardium and cardiac jelly forms ______________ ________________.
    endocardial cushion
  5. Outer myocardial mantle becomes _________________ heart wall.
    muscular
  6. The 5 primitive areas of the heart are:
    • 1. sinus venosus
    • 2. common atria
    • 3. common ventricle
    • 4. conus cordis (future LV & RVOT's)
    • 5. Truncus Arteriosus (roots AO & pulmonary arteries)
  7. What is looping?
    When does it occur?
    Looping of heart tubes as they grow at a faster rate than the pericardium. Dextro=Rt=normal. Levo=left=malposition of vent or great vessels

    Looping starts at day 24
  8. Heart begins to beat at day _________.
    22
  9. Circulation of heart begins at day _____to____.
    27-29
  10. Sinus venosus - Lt horn becomes:
    oblique vein of LA & coronary sinus
  11. Sinus venosus Rt horn becomes:
    Part of RA, IVC, SVC
  12. What is the most posterior part of embryological heart
    sinus venosus left horn
  13. IAS forms between _____ & _____ day.
    27-37th day
  14. There are 3 events of IAS formation. Explain
    • 1. Septum Primum (divides atrium to Lt & Rt sides)
    • 2. Septum Secundum (forms superior portion of RA adjacent to septum primum; oval shaped opening persists
    • 3. Fossa Ovalis (early remnants of sinus venosus tissue found @ jxn of IVC & SVC with RA)
  15. Expain the events of Ventricular Septal Formation: (3)
    • 1. Lateral aspect expanding faster than medial = med invagnation=gradually fuses to form a portion of IVS. Small opening @ level AV valves permits con't communication.
    • 2. Muscular IVS forms passively by expansion of ventricle (27th day)
    • 3. MMB IVS forms actively by growth of endocardial cushion (b/c it has a bigger job)
  16. Explain the events of AV Canal Formation: (3)
    • 1. 30-40 days - 4 mesenchymal swellings appear.
    • 2. 2 endocardial cushions = septal TV leaflet & AMVL and a portion of inflow perimmb IVS
    • 3. 2 lateral cushions = ATVL, PTVS, PMVL
  17. The events of outflow tract formation are: (3)
    • 1. Conus Cordis divides outflow tract into Rt & Lt.
    • 2. 2 swellings in truncus arteriosus form septum dividing into AO and pulmonic and twist around each other as they expand therefore the spiral relationship(begins at distal end from truncus -->conus cordis
    • 3. Tubercles on main truncus swelling responsible for formation of AO and pulmonic valves
  18. 3rd set of AO arches becomes the _____________________?
    CCA & ICA
  19. 4th set AO arches becomes _____________________.
    Aorta
  20. 6th set AO arches becomes ___________________________.
    Rt & Lt Pulmonary Arteries
  21. The distal portion of 6th AO arch remains in connection to arterial system via ______________ ______________.
    ductus arteriosus (pulmonary to systemic shunt)
  22. Fetal Circulation Review: O2 blood from placenta returns IVC and shunts across the ___________.
    IAS
  23. Summary:
    3 weeks =
    4 weeks=
    6-8 weeks=
    • 5-6 part primitive cardiac tube
    • carciac loop begins
    • all 4 chambers are complete
  24. What is the cardiogenic region?
    Horseshoe shaped region b/f endocardial cushion done forming valves.
  25. What is the septum primum in an adult called?
    Fossa ovalis
  26. Right atrium - atrial fold - helps direct O2 IVC blood across IAS to fetal circulation =
    eustachian valve
  27. Image Upload 2
Author
lstaal1
ID
22021
Card Set
Echo 530
Description
Embryology of Heart
Updated