The Heart and Fetal Circulation

major components of the cardio system

heart, blood vessels, blood

functino of the cardio system

transportation of nutrients and oxygen, waste products, and horomones

what cavity is the heart in

middle mediastinum

what are veins

carry blood to heart

what are arteries

carry blood away from heart

what is the purpose of auricles on the outside of heart

increase holding capacity of atria

1

right atrium

2

right ventricle 

3

left atrium

4

left ventricle

what are the great vessels of the heart

superior vena cava, inferior vena cava, pulmonary veins, pulmonary trunk/arteries, aorta

1

SVC

2

pulmonary arteries

3

pulmonary veins

4

IVC

5

aorta

6

pulmonary trunk

where does the SVC return blood from

thoracic wall, upper limb, head and neck

where does the IVC return blood from

abdomen, pelvis, and lower limbs

what does the right atrium receive deoxy blood from

SVC, IVC, coronary sinus

what does the pulmonary trunk bifurcate into 

right and left pulmonary arteries 

what does the left atrium receive blood from

4 pulmonary veins

• 2 right and 2 left

how is backflow prevented in chambers

valves

what are the valves of the heart

tricuspid, bicuspid/mitral, pulmonary semilunar, aortic semilunar

what valve prevents backflow between right atrium and right ventricle 

tricuspid valve

what valve prevents backflow between left atrium and left ventricle

bicuspid/mitral valve

what prevents backflow between right ventricle and pulmonary trunk

pulmonary semilunar valve

what prevents backflow between the left ventricle and the aorta

aortic semilunar valve

1

pulmonary semilunar

2

right AV, tricuspid

3

chordae tendineae

4

papillary muscle

5

left AV/bicuspid/mitral

6

aortic semilunar

what is it called when ventricles contract to pump blood out of heart

systole

what closes in systole

tri and bi valvles

what sound is systole 

S1 “lub”

what is it called when the ventricles relav and blood fills them

diastole

what is closed in diastole

pulmonary and aortic valves

what sound is diastole

S2, “dub”

what are the layers of heart (superficial to deep)

epicardium, myocardium, endocardium

is the RV or LV thicker

LV - has to pump to whole body 

1

pectineate muscle

2

fossa ovalis

3

opening of coronary sinus

1

trabeculae carneae

what is trabeculae carnea

rib of muscle that is in RV and LV that attachtes to papillary muscles

when is main blood flow into the coronary circulation

diastole (when heart is relaxed)

why can blood not flow into myocardium in systole

contraction of myocardium compresses coronary arteries and the entrances of the coronary circulation are blocked becasue the aortic semilunar is open

1

right coronary artery

2

right marginal artery

3

posterior interventricular artery

4

left coronary artery

5

circumflex artery 

6

anterior interventricular artery

1

small cardiac vein

2

coronary sinus

3 

great cardiac vein

4

middle cardiac vein

1

base of aorta

2

right coronary artery 

3

left coronary artery 

4

right marginal artery

5

posterior interventricular artery

6

anterior interventricular artery

7

circumflex artery

8

small cardiac vein

9

middle cardiac vein

10

great cardiac vein

11

coronary sinus

12

right atrium

1

superior vena cava

2

sinoatrial (SA) node (pacemaker)

3

internodal pathway

4

atrioventricular (AV) node

5

atrioventricular bundle of His

6

bundle branches

7

purkinje fibers

8

right atrium

9

left atrium

10

purkinje fibers

11

interventricular septum

what alters the intrinsic cardiac muscle contraction set by pace maker cells

para/sympathetic activation

fetal circulation facts:

non-functioning lungs, cannot provide own nutrients, cannot remove own waste, use mothers circulation to fulfill deficiencies

what provides the fetus with nutrients and maternal and fetal blood to communicate

placenta

how does the placenta communication occur

via umbilical vessels in umbilical cord, there is 1 umbilical vein, and 2 umbilical areries 

what is the umbilical veins pathway

through primitive liver and carries oxygenated blood to the IVC

what does the umbilical vein regress to

ligamentum teres (round ligament of the liver)

what is a hole that shunts blood from the RA to the LA and bypass lungs in utero

foramen ovale

what does the foramen ovale become post utero

fossa ovalis 

what is a utero thing that shunts blood that made it to the left pulmonary artery to the aorta

ductus arteriosus

what does the ductus arteriosis regress to

ligamentum arteriosum

1

foramen ovale

2

umbilical vein

3

ductus arteriosis