Heart Development Flashcards
1st sign of a heart, solid horseshoe shaped cluster of cells
Primary heart field
Islands will unite and form a horseshoe shaped endothelial lined tube surrounded by myoblasts within the cardiogenic region called…
endocardial tubes
Lateral folding creates…
primordial heart tube
This repositions the developing heart
Cranial-Caudal folding
Attaches the heart tube to the dorsal side of pericardial cavity
dorsal mesocardium
Formed when the middle section of dorsal mesocardium disappears
Transverse Pericardial sinus
Different sections of developing heart from in–>out (inferior to superior in picture)
Spike A Volley Ball
- Sinus Venosus
- Primordial Atrium
- Promordial Ventricle
- Bulbus Cordis
2 parts that make up the Bulbus Cordis
Truncus Arteriosus and Conus Cordis
What does TRUNCUS ARTERIOSUS become?
Pulmonary trunk and aorta
What des CONUS CORDIS become?
Outflow tract of ventricles; caudal portion forms Right Ventricle
What does PRIMORDIAL VENTRICLE become?
Left ventricle
What does PRIMORDIAL ATRIUM become?
Right and left auricles and portions of the atria
What does SINUS VENOSUS become?
Coronary sinus and sinus venarum
Does the heart look to the right or left?
Right
Circulation through the primordial heart (day 30)
Sinus Venosus–Primordial atrium–av canal–left ventricle–IV foramen–Right ventricle–Conus cordis–Truncus arteriosus–aortic sac–pharyngeal arch aa–dorsal aortae
Sinus venosus receives venous blood from what 3 paired veins? (Medial to lateral)
- Vitelline vv
- Umbilical vv
- Common Cardinal vv
what horn of the sinus venosus becomes larger and why?
Right Horn
Blood flow tot he heart shifts to the right side due to the remodeling of the 3 veins.
Left sinus horn becomes what two structures?
- Oblique veins of the left atrium
2. Coronary Sinus
What happens to the right sinus horn?
Becomes incorporated intot the right atrium to form the smooth wall portion
What is the name of the entrance formed by the right sinus horn merging with the right atrium?
Sinus Venarum
2 ways to form septa of the heart
- Endocardial cushions (Atria)
2. Merging two expanding portions of the wall (ventricles)
Around the end of week 4, a crest of tissue grows from the roof of the common atrium, this structure is called?
Septum Primum
Perforations in septum primum form…
ostium secundum
Grows just to the right of septum primum and creates what opening?
Septum secundum grows inferior and creates foramen ovale
how does foramen ovale close and what does it form?
A change in pressure causes septum primum to adhere to septum secundum creating the FOSSA OVALIS
Complete closure of the interventricular foramen is done by what and forms what?
Done by outgrowth of inferior endocardial cushion and forms the membranous part of the interventricular septum
- Most common congenital heart defect
* Failure of IV septum to completely form
Ventricular Septal Defect (VSD)
