W3- heart development

Question 1

what structures do neural crest cells contribute to in heart development

Answer 1

Migrates from neural tube to the aortic artery and to arch 3,4,6

Endothelium of the aortic arch

outflow tracts

Endocardial cushion

Heart conduction

Valve formation

ANS neuron development

Question 2

what other defects are associated with congenitial heart defects as a result of abnormal NCC

Answer 2

craniofacial abnormalities, defects in the parathyroid, thyroid and thymus

Question 3

what would a defect in NKX2-5 (Tinman) cause

Answer 3

regulates heart formation so defect in this leads to defect in endocardial tube

Question 4

what direction does blood flow in the embryo

Answer 4

caudal to cranial

Question 5

what does the truncus arteriosus differentiate into

Answer 5

aorta and pulmonary trunk

Question 6

what does the bulbus cordis differentiate into

Answer 6

smooth part of right ventricle (conus arteriousus)

smooth part of left venticle (aorticle vestibule)

aortic valves, pulmonary valves, aortic vestibule [LV], conus arteriosus/infundibulum [RV])

Question 7

what does the primitive ventricle differentiate into

Answer 7

trabeculated ventricle R and L

Question 8

what doe sthe primitive atrium differentiate into

Answer 8

trabeculated atrium R and L

Question 9

what does the sinus venosus differentiate into

Answer 9

R –> smooth part of R atrium

L –> coronary sinus

oblique vein

Question 10

where is the sinus transverse cardiac sinus located

Answer 10

Between pulmonary trunk, aorta and SVC and used in surgery

Question 11

what are the Pectinate muscles and the trabeculae carneae derived from

Answer 11

primitive atria

primitive ventricle

Question 12

what 3 structures lead to the formation of the smooth walls in the heart and what do these turn into

Answer 12

smooth walls are the inflow and outflow tracks

pulmonary vein, R sinus venosus, bulbus cordis

Both ventricles (outflow)- bulbus cordis

Left atrium (outflow)– pulmonary vein

Right atrium (outflow)– sinus venarum from the right horn of the R sinus venosus

Question 13

what structure seperates the trabeculated wall and the smooth wall of the heart

Answer 13

Crista terminalis

Question 14

what is a defect that can occur during dextral looping

Answer 14

dextrocardia= right sided heart

Question 15

what forms the AV valves

what forms the semilunar valves

Answer 15

AV- endocardial cushion

semilunar- bulbis cordis

Question 16

what are endocardial cushions formed from

Answer 16

NCC and jelly that is secreted from the mesocardium

Question 17

what structures do the endocardial cushions contribute to

Answer 17

Mitral and bicuspid valves

Chordinae tendinae and papillary muscle

Question 18

where does the endocardial cushion fuse to induce AV septation

Answer 18

Endocardial cushions fuse to septum prima

Question 19

what leads to hypoplasia of the left atrium

Answer 19

clamping of the umbilical cord and decreased blood flow from the placenta

Question 20

is the valve located in the septum primum or septum secundum

Answer 20

septum primum

septum secundum contains the foramen ovale which persists after closure as an indentation called the fossa ovalis

Question 21

what three structures must fuse to complete the ventricular septation

Answer 21

membranous portion of IVS (there is a muscular one as well)

endocardial cushions

conotruncal ridges

Question 22

what may occur as compensation for TGA

Answer 22

failure of fushion of the endocardial cushion/ IVS/conotruncal ridge and the formation of a Interventricular septum

Question 23

outline the process of OFT septation

Answer 23

Neural crest cells associated with pharyngeal arches 3, 4 and 6 migrate into the truncus arteriosus and bulbus cordis –> forms conotruncal ridges –>

Elongation of arterial end –>

Ingrowth of the aorticopulmonary septum –>

counterclockwise rotation -_>

convergence of OFT, AV, and ventricular septa

Question 24

how does an overarching aorta form

Answer 24

unequal split and the aorta will take some of the deoxy blood from right because its too big

Question 25

what region may exhibit abnormal genesis in Transposition of the great

Answer 25

conotruncal region

aberrant neural crest cells migration in this region

pulmonary valvular atresia

Question 26

what is the proper arrangement of the great arteries

Answer 26

with the pulmonary trunk exiting the heart anterior to the aorta and spiraling behind the aorta as it travels distally