The pathophysiology of congenital heart disease

Question 1

What are the 3 general etiologies of CHD?

87% of the etiology of CHD is _____.

Answer 1

1. genetic
2. environmental (drugs, chemicals, viruses, maternal disease)
3. mutifactoral: combo of gen and enviro (myocarditis that progresses)

87% = multifactorial

Question 2

What are the common genetic syndromes are assc with also having of CHD?

Answer 2

down syndrome (50%) 
turners (20%)
marfan (60%)
trisomy 18 (90%) 
trisomy 13 (80%)
DiGeorge (80%)
Noonan
WIlliams

Question 3

What are the common environmental factors for the development of CHD?

Answer 3

1. infections (Rubella in baby)
2. Diseases (PKU in baby, DM in mom)
3. drugs (thalidomide, dilantin, trimethadione, psychoprophics)
4. toxins (alcohol)

Question 4

How does fetal circualtion determine cardiac development

Answer 4

dec flow to the right side –> small right sided structures

dec flow to left –>

Question 5

At birth, how does the babys circualtion change? (normal) what would happen in pulmonary HTNN

Answer 5

systemic resistance increases
pulmonary resistance decreases

pulmonary vasular resistance=
1/2 of systemic after 24 hrs
may take 2-6 weeks to develop adult levels

dec Q to LV –> organ failure

Question 6

closure of ductus arteriosis and ductus venous occurs in ___ (time)

Answer 6

days

Question 7

closure of formamen ovale occurs in ____ (time)

Answer 7

weeks to months

Question 8

ventricular septal defect: what does the echo show as the child gets older?

Answer 8

initially no hypertrophy

2wk-2mo: LVH

1-2 yrs: RVH

Question 9

ventricular septal defect: how does pulmonary flow change as the child gets older?

Answer 9

initially: nml

2wk-2mo: increased pulmonary flow (because pulm resistance is less than systemic resistance)

1-2 years: decreased pulmonary flow

Question 10

When will a child with VSD begin to appear cyanotic?

Answer 10

~1-2 years (related to pulmonary resistance??)

Question 11

Physiologic/innocent murmurs are never…

Answer 11

diastolic

associated with a thrill

Question 12

Murmurs: In AV valves, regurgitation is heard during (systole/diastole) and stenosis is heard during (systole/diastole).

Answer 12

systole

diastole

Question 13

Murmurs: In semilunar valves, regurgitation is heard during (systole/diastole) and stenosis is heard during (systole/diastole).

Answer 13

diastole

systole

Question 14

Atrial septal defects have murmurs of relative stenosis of (which valves)?

Answer 14

pulmonary stenosis
tricuspid stenosis

(is this WTF all of her letters meant?)

Question 15

Ventricle septal defects and AV canal defects have murmurs of relative stenosis of (which valve)?

Answer 15

mitral stenosis

Question 16

Most common congenital heart defect? Then what?

Answer 16

ventr septal defect

transposition of great arteries

Question 17

Cyanosis occurs when there is a desaturated concentration of hgb greater than…

Answer 17

4

Question 18

Cyanosis may be caused by

Answer 18

central apnea
pneumonia/pneumothorax
shunting
some heart defects

Question 19

Hypoplastic left heart syndrome presents with what abn on echo? Is this a cyanotic or non-cyanotic defect?

Answer 19

small LV with very low volume

cyanotic

Question 20

What are the cyanotic congenital heart defects?

Answer 20

I Truncus Arteriosus 
II Transposition of Gr Arteries
III Tricuspid Atresia
IV Tetralogy of Fallot
V Total Anomalous Pulmonary Venous Return

Mnemonic: 1 trunk, 2 arteries; tri = 3; tetr = 4; 5 = 5 words

Question 21

In Total Anomalous Pulmonary Venous Return, the blood mixes in the:

Answer 21

RA

Question 22

An unrestrictive VSD in a newborn infant is likely to be associated with little or no:

Answer 22

murmur

it takes ~2 mo for the pulm resistance to fall

Question 23

Systolic murmur in left upper sternal border in a patient with an ASD is caused by:

Answer 23

relative pulmonary stenosis from increased pulmonary flow