First Aid Usmle Step 1: Cardiology

Front 1

Truncus arteriosus gives rise to?

Back 1

ascending aorta and pulmonary trunk

Front 2

Bulbus cordis gives rise to?

Back 2

Smooth parts of left and right ventricles

Front 3

primitive ventricle gives rise to?

Back 3

trabeculated left and right ventricle

Front 4

primitive atria gives rise to?

Back 4

trabeculated left and right atria

Front 5

Left horn of sinus venosus (SV) gives rise to?

Back 5

coronary sinus-vein that drains heart into RA

Front 6

Right horn of SV gives rise to?

Back 6

smooth part of RA

Front 7

Right common cardinal vein and rigth anterior cardinal vein gives rise to?

Back 7

SVC

Front 8

What cells is the truncus arteriosus derived from?

Back 8

neural crest cells

Front 9

If the TA does not septate, what are the potential outcomes?

Back 9

Transposition of the great vessels (failure to spiral)
Tetralogy of Fallot (skewed AP septum development)
Persistent TA (partial AP septum development)

Front 10

What do the endocardial cushions do?

Back 10

separate atria and ventricles and contributes to the interventricular septum

Front 11

What is Eisenmenger's syndrome?

Back 11

uncorrected VSD, ASD, or PDA
L-->R shunt uncorrected causes and incr. pressure in the pulm. vasculature-->hypertrophy of pulmonary vasculature and increased resistance-->increased pressure in right heart-->shunt reverses to R-->L so that now deoxygenated blood is entering the aorta and going to the body-->late cyanosis

Front 12

What are the defects associated with endocardial cushion defects?

Back 12

Ebstein's anomaly: weak underdeveloped RV, assoc. w/ Lithium use in Mom

Tricuspid atresia: tricuspid valve does not form correctly, underdeveloped R side of heart
*need ASD or VSD for fetus to be viable

Front 13

Describe the steps in interatrial septum development

Back 13

1. Foramen primum narrows as Septum primum grows toward the endocardial cushions
2. Septum primum has perforations that create Formaen secundum
3. Septum secundum contains a permanent opening called Foramen ovale
4. Septum primum degenerates, but remaining part forms the valve of foramen ovale

Front 14

What is the most common hemodynamically significant ASD?

Back 14

Defect in foramen secundum-stays open

Front 15

What is the danger of a patent foramen ovale?

Back 15

microemboli that travel to the R heart can travel to the left side of the heart without passing through the lungs which would absorb the clot. If the clot enters the left side of the heart, it can go to the brain and cause infarctions there.

Front 16

Where is erythropoiesis occuring before birth?

Back 16

Yolk sac= weeks 3-10
Liver= weeks 6-birth
Spleen= weeks 15-30
Bone marrow= week 22- adult

Front 17

Fetal hemoglobin is composed of?

Back 17

2 alpha chains and 2 gamma chains

Front 18

Adult hemoglobin is composed of?

Back 18

2 alpha chains and 2 beta chains

Front 19

What maintains the ductus arteriosus to stay open?

Back 19

Prostaglandin E1 and E2
(low O2)

Front 20

What drug can be used to close the ductus arteriosus?

Back 20

Indomethacin

Front 21

Coronary artery occlusion occurs most commonly in which artery?

Back 21

LAD

Front 22

When do the coronary arteries fill?

Back 22

diastole

Front 23

Which coronary artery does the PDA come from?

Back 23

85% of the time from the right coronary
8% of the time from the left coronary circumflex
7% is codominant circulation from both LCX and RCA

Front 24

What are ways to calculate CO?

Back 24

CO=SV x HR
CO= rate of O2 consumption/AO2-VO2 content

AO2 (mL/dL)= [Hg] x 1.34 x AO2 saturation

Front 25

How can you calculate MAP?

Back 25

MAP=CO x TPR
MAP= 2/3 diastolic BP + 1/3 systolic BP

Front 26

How can you calculate pulse pressure?

Back 26

PP= SBP-DBP
PP proportional to SV

Front 27

SV=

Back 27

CO/HR= EDV-ESV

Front 28

EF=

Back 28

SV/EDV
normal >55%

*Decreases in systolic heart failure

Front 29

Change in pressure=

Back 29

Q x R

Front 30

Resistance =

Back 30

change in pressure/ Q= 8n x length/pi r^4

Front 31

Total resistance of vessels in series or parallel

Back 31

series= R1+ R2 + R3...
parallel
1/Rtotal= 1/R1 + 1/R2 + 1/R3....

Front 32

What conditions/states increase viscosity?

Back 32

increased hematocrit:
-polycythemia
-hyeprproteinemic states (ex: multiple myeloma)
-hereditary spherocytosis

Front 33

when does viscosity decrease?

Back 33

anemia

Front 34

Tension=
LaPlace's law

Back 34

P x r/m

m=wall thickness

Front 35

Net filtration pressure

Back 35

Pnet= (Pc+ interstitial colloid) - (Pi + capillary colloid)

Front 36

net fluid flow=

Back 36

Jv= Kf x Pnet
Kf is a filtration constant (capillary permeability)

Front 37

what is the most common congenital cardiac anomaly?

Back 37

VSD > ASD > PDA

Front 38

Tetralogy of Fallot

Back 38

Pulmonary infundibular stenosis
RVH
Overriding aorta
VSD

pulm. stenosis forces R-->L shunt and causes RVH (boot shaped heart)

*squatting reduces blodo flow to legs-->incr. PVR-->decr. cyanotic R-->L shunt across VSD

Front 39

D-transposition of great vessels

Back 39

Aorta leaves from RV and pulmonary trunk leaves from LV

-not compatible with life unless there is a shunt (ASD and VSD)

*Diabetic moms

Front 40

Coartation of the aorta-infantile type

Back 40

aortic stenosis proximal to insertion of ductus arteriosus (preductal)
-assoc. w/ Turner syndrome

Pink upper extr., blue lower extr.

Front 41

Coarctation of the aorta-adult type

Back 41

distal to ligamentum arteriosum (postductal)

-notching of ribs (collateral circulation)
-HTN in upper extr.
-weak pulses in lower extr.

Commonly assoc. w/ bicuspid aortic valve

Front 42

PDA

Back 42

fetal period: R-->L shunt
neonatal period: lung resist. decr.-->shunt becomes L-->R with RVH and/or LVH and failure

-continuous machine-like murmur

late cyanosis in lower extremities (differential cyanosis)

Front 43

22q11 syndromes are assoc. w/ what heart conditions?

Back 43

Truncus arteriosus
tetralogy of fallot

Front 44

Down Syndrome is assoc. w/ what heart defects?

Back 44

ASD, VSD
AV septal defect (endocardial cushion defect)

Front 45

Congenital rubella presents with what heart defects

Back 45

septal defects
**PDA
pulmonary artery stenosis

Front 46

Turner syndrome heart defects

Back 46

Coarctation of the aorta (preductal)
bicuspid aortic valve

Front 47

Marfan's syndrome heart defects

Back 47

Aortic insufficiency and dissection (late complication)

Front 48

Infant of diabetic mother-heart defects

Back 48

transposition of great vessels