Week 1: Friday

Question 1

why would the fetus die without a patent foramen ovale

Answer 1

the heart would not recieve sufficient blood because it would go to the non-functioning lungs and therefore the fetus would not recieve proper nutrients and oxygenated blood - die bc cant breathe or not getting enough oxygenated blood

Question 2

what makes the foramen ovale close at birth

Answer 2

When a baby’s lungs begin working, blood flow through the heart changes. Now the oxygen-rich blood comes from the lungs and enters the left atrium. At this point, blood flow follows the normal route. The pressure of the blood pumping through the heart usually forces the flap opening of the foramen ovale to close

Question 3

if the ventricular septum does not close completely (ventricular septal defect), a shunt will occur between the ventricles. Which way would the blood tend to flow across this shunt after birth? What organ would become overloaded with blood?

Answer 3

• right side of heart to go across VSD and into aorta
• dilution of aortic blood with low oxygen blood from right heart = cyanosis
• aorta gets overloaded with blood

Question 4

which way does blood flow through the primitive tube

Answer 4

primitive artium - primative ventricle - bulbus cordis - truncus arteriosus

Question 5

what will the structure truncus arteriosus form?

Answer 5

aortic arches and most cranial portion becomes the pulmonary arteries

Question 6

what is the fetal ductus arteriosus

Answer 6

• blood vessel that connects the pulmonary artery to the aorta ( R to L flow)
• allows blood to bypass the lungs, which are not inflating or exchanging oxygen

Question 7

what happens in the first week of life

ductus arteriosus

Answer 7

• inflation of lungs and increase in oxygen tension of blood causes smooth muscle in the ductus to constrict, closing the ductus
• if smooth muscle ring is not complete and ductus remains open - patent ductus arteriosus (PDA)

Question 8

what is patent ductus arteriosus

Answer 8

blood flow moves from aorta to pulmonary artery (L to R) is high velocity and turbulent

Question 9

what does the ductus arterisosum turn into in adults

Answer 9

ligamentum arteriosum

Question 10

what are the clinical consequences of PDA

Answer 10

• continual high speed flow from the aorta through PDA into pulmonary artery
• continuous heart murmur
• increased blood flow within the blood vessels that form the PDA circuit
• overcirculation causes development of congestion in the tissue of the lungs: pulmonary edema

Question 11

what are the clinical evaluations of PDA

Answer 11

• radiographs, angiography
• echocardiography

Question 12

what is the treatment of PDA

Answer 12

• surgical ligation around the PDA at open chest surgery
• device occlusion of the PDA

Question 13

what is the prognosis once PDA is occluded

Answer 13

good long-term

Question 14

what is the valve that connects pulmonary artery and right ventricle

Answer 14

pulmonary valve

Question 15

what is the valve that connects the aorta and left ventricle

Answer 15

aortic valve

Question 16

how are the semilunar valves formed

Answer 16

• interior wall of embryonic vessels undergo remodeling and sculpting
• series of swellings that come out that form the primitive valve
• to form valve, cells around it regress/apoptosis
• left with fine, delicate structures

Question 17

what is a common congenital malformation of semilunar valves

Answer 17

• failure of valve leaflets to fully separate
• fused leaflets, failure to open during ventricular contraction

Question 18

what is valve stenosis

Answer 18

valve opening is narrowed

Question 19

what does pulmonic valve stenosis cause

Answer 19

• increase in heart muscle mass
• decreased blood flow
• arrhythmias (abnormal heart rhythms)
• congestive heart failure
• exercise intolerance
• fainting

Question 20

what is treatment of pulmonic stenosis

Answer 20

• go into jugular vein then cranial vena cava then RA then RV then pulmonic valve
• insert catheter that has deflated balloon and inflate balloon to open valve

Question 21

what is ventricular septation

Answer 21

• ventricular septum divides the ventricle in left and right halves
• allows blood to flow in series with no mixture of unoxygenated and oxygenated blood

Question 22

what does the bulbus cordis do

Answer 22

helps form the dorsal portion of the septum, continues into truncus arteriosus, which forms spiral structure of the aorta and pulmonary artery

Question 23

where does the bulbus cordis need to line up

Answer 23

lines up with interventricular septum to place the pulmonary artery over the right ventricle and aorta over left ventricle

Question 24

what is tetraology of fallot

Answer 24

4 defects resulting from failure of conotruncal septum to align with the ventricular septum

Question 25

what are the 4 defects of TF

Answer 25

1. failure of ventricular septum to fully close, VSD
2. narrowed right-sided opening from RV leading to pulmonic valve stenosis
3. rightward deviaition of the left sided opening from the lV leading to rightward positioning of aorta
4. right heart enlargement secondary to pulmonic valve stenosis

Question 26

what are the consequences of T of F

Answer 26

• allows blood from right side of heart to go across VSD and into aorta
• dilution of aortic blood with low oxygen blood from right heart - cyanosis

Question 27

what is persistent right aortic arch (PRAA)

Answer 27

• right aortic arch persists and left aortic arch regresses
• PRAA and remnants of the left arch encircle and constrict the esophagus

Question 28

what are the consequences of PRAA

Answer 28

megaesophagus and regurgitation

Question 29

surgical correction of PRAA

Answer 29

cut left ligamentum