Heart & Thoracic Anatomy

Question 1

Purpose of the CV system

Answer 1

Delivers O2 + nutrients to tissues

Removes waste products

Question 2

Where is the heart located?

Answer 2

In the mediastinum

Question 3

Purpose of the pericardium

Answer 3

Surrounds + protects the heart

Fuses with the diaphragm (so heart stays in place)

Question 4

Relationship between diaphragm and heart

Answer 4

When diaphragm moves while breathing, heart moves slightly –> helps BF through heart

Question 5

Where does the SVC carry blood?

Answer 5

To heart from upper body

Question 6

Where does the IVC carry blood?

Answer 6

To heart from lower body

Question 7

Sections of the mediastinum (x4)

Answer 7

Anterior, middle, posterior and superior

Question 8

What is in the anterior mediastinum?

Answer 8

Thymus gland

Question 9

What is in the middle mediastinum?

Answer 9

Heart, asc. aorta, pulmonary trunk, phrenic nerves

Question 10

What is in the posterior mediastinum?

Answer 10

Descending aorta, esophagus, vagus n. and thoracic duct

Question 11

What is in the superior mediastinum?

Answer 11

Aortic arch, esophagus & trachea

Question 12

Characteristics of the thymus gland

Answer 12

Bigger in childhood vs adulthood (atrophy occurs)

Development of T cells in immune system before birth + during childhood

Question 13

Purpose of auricles

Answer 13

Allows the L and R atriums to increase blood capacity

Question 14

What is the coronary sulcus?

Answer 14

Groove between atria & ventricles

Question 15

What are the interventricular sulci?

Answer 15

Two of them - ant. and post.

Between right and left ventricles

Question 16

Where is the right coronary artery found?

Answer 16

Coronary sulcus

Question 17

What does the R coronary a. branch off to?

Answer 17

Posterior interventricular a. and R marginal a.

Question 18

What does the L coronary a. branch off to?

Answer 18

Circumflex a. (coronary sulcus)

L ant. desc. a. (LAD) interventricular a.

Question 19

What do the cardiac a. do?

Answer 19

Bring O2 and nutrients –> cardiac tissue

Question 20

Purpose of coronary veins

Answer 20

Removal of CO2 and waste

Question 21

Which coronary veins drains into the coronary sinus then RA? (x3)

Answer 21

Small cardiac

Middle cardiac

Great cardiac

Question 22

Which vein drains directly into the RA?

Answer 22

Anterior cardiac vein

Question 23

Where is the small cardiac vein found?

Answer 23

Coronary sulcus

Question 24

Where is the middle cardiac vein found?

Answer 24

Post. interv. s.

Question 25

Where is the great cardiac vein found?

Answer 25

Ant. interv. s.

Question 26

Layers of the pericardium

Answer 26

Fibrous pericardium Serous pericardium

Question 27

Characteristics of fibrous pericardium

Answer 27

Dense, irregular CT Protects + anchors heart (connected to diaphragm + prevents heart over-stretching)

Question 28

Characteristics of serous pericardium

Answer 28

Parietal layer - secretes serous fluid (lines the cavity) Visceral layer (aka epicardium) - secretes serous fluids + adheres to heart wall, lines the heart

Question 29

Purpose of the pericardial cavity

Answer 29

Space between the 2 layers of pericardium Both layers secrete serous fluid into here Lubricates the heart + prevents friction

Question 30

Layers of the heart wall

Answer 30

Epicardium Myocardium: has specialized cardiac muscle tissue Endocardium: lines heart chambers: smooth lining = less friction

Question 31

Cause of myocarditis

Answer 31

Viral infection, radiation, meds

Question 32

Cause of endocarditis

Answer 32

Often bacterial --> affects heart valves

Question 33

Why are atrial walls thin?

Answer 33

Don't need a lot of muscle to deliver blood --> ventricle

Question 34

Why are ventricle walls thick?

Answer 34

Need to move blood from ventricles --> body tissues under a high pressure

Question 35

Why is the LV wall thicker than RV?

Answer 35

LV has to work harder to get blood to tissues (greater distance, high pressure + resistance to BF)

Question 36

Purpose of fibrous rings

Answer 36

Structural foundation Maintains valve diameter Attachment site for muscle fibers Electrically separates the atria from the ventricles

Question 37

Where are AV valves located?

Answer 37

Between atria & ventricles

Question 38

Where are SL valves located?

Answer 38

Between ventricles and great vessels

Question 39

AV valves and chordae tendinae

Answer 39

Cusps of AV valves have chord tendinae --> connect to papillary muscles

Question 40

What is a subvalvular apparatus?

Answer 40

Chordae tendinae + papillary muscles Open + close AV valves

Question 41

What are papillary muscles made up of?

Answer 41

Trabeculae carnae: bundles of cardiac muscle fibers

Question 42

Purpose of heart valves

Answer 42

Ensure one way direction of blood flow

Question 43

What is ventricular diastole? Relation to AV valves

Answer 43

Blood drains from atria --> ventricles AV valves are relaxed

Question 44

What do the AV valves do during ventricular systole?

Answer 44

They close --> taut chordae tendinae

Question 45

What is AV valve prolapse?

Answer 45

When cusps open into atria during ventricular contraction

Question 46

When do SL valves open?

Answer 46

During ventricular contraction --> increased pressure in the ventricles Pushes blood against the SL valves Blood is ejected into the great vessels

Question 47

When do the SL valves close?

Answer 47

During ventricular diastole --> blood flows back into ventricles Blood catches behind valve cusps --> closes and the back pressure from the blood on the valves keeps them closed

Question 48

Heart valve stenosis

Answer 48

Narrow heart valve --> constricted BF Due to: congenital defect, scarring + age

Question 49

Mitral valve prolapse

Answer 49

Causes: genetic disorder & CT damage

Question 50

Why don't venous entry points have valves?

Answer 50

When atria contracts, the muscle compresses the weak walls of the openings --> causes them to almost collapse