3. Heart and Pericardium

Question 1

What are the different parts of the thoracic mediastina? Where is the heart, esophagus and aorta found in the thoracic mediastina?

Answer 1

anterior, middle and posterior compartment

heart: middle part

esophagus and aorta in the posterior part

Question 2

What are the three parts of the pericardium?

Answer 2

(most exterior): fibrous pericardium: thick and continuous onto diaphragm

serious pericardium (2):

• parietal pericardium (if you reflect the fibrous pericardium youll find the parietal pericardium)
• visceral pericardium: covers heart and epicardial fat

Question 3

In the lab, how can you identify the fibrous pericardium and serous pericardiums?

Answer 3

1. if you cannot see the different parts of the heart => fibrous pericardium
2. if you reflect that external sheat => parietal pericardium
3. on heart and see compartments of heart => visceral pericardium

Question 4

What is the function of epicardial fat?

Answer 4

the heart is a muscle thus has muscle fibers that require O2 and nutrients brought by coronary arteries => fat protects coronary arteries

Question 5

What are the four chambers of the heart?

Answer 5

right ventricule and atria (more anterior)

left ventricule and atria (more posterior)

Question 6

Where do all deoxygenated blood travel to?

Answer 6

the right atrium

Question 7

What separates the right and left ventricule looking inside the heart?

Answer 7

interventricular septum

Question 8

Explain the orientation of the heart (the various surfaces).

Answer 8

Question 9

How do you know you’ve properly aligned your heart?

Answer 9

when SVC and IVC have lined up and the apex in pointing torwards the left (looking at the heart anteriorly)

Question 10

Which side of the heart contains oxygenated blood? What transports oxygenated blood? What about deoxygenated blood?

Answer 10

right side of the heart: deoxygenated blood carried by pulmonary arteries

left side of heart: oxygenated blood carried by pulmonary veins

Question 11

Explain where the trajecgtory of blood from the head to heart. from the limbs to the heart.

Answer 11

from the head: blood travels from the superior vena cava -> right atrium -> right ventricule -> pulmonary trunk -> pulmonary arteries -> lungs

from limbs (inferior vena cava

Question 12

What is the anatomical landmark of the pulmonary trunk?

Answer 12

the sternal angle (T4/T5)

Question 13

Identify the various parts of the heart (arrows, yellow purple).

Answer 13

1. upper arrow: pectinate muscle: in wall of atrium for atrium contraction
2. pectinate muscle becomes the crista terminalis (smooth) (in yellow) which separates the 2 atria
3. lower arrow: valve of IVC
4. (purple) fossa ovalis

Question 14

Identify these 2 structures

Answer 14

the left and right aurricle (when looking at heart, you cant see the atrium, you see the auricles)

Question 15

Explain what the fossa ovalis is.

Answer 15

in fetus: oxygen and nutrients in blood is provided to fetus through the placenta of the mother connected to the umbilical cord which connects to the inferior vena cava of the baby. The heart of the fetus has a FORAMEN OVALE: which connects the right atrium to the left atrium (fetus does not require much blood to lungs) which allows the blood to travel directly to the left atrium (to then go to the body). Once born, the baby doesn’t need the foramen ovale anymore which closes off the become the fossa ovalis (found in the right atrium)

Question 16

What valve can be found between the right atrium and the right ventricule? Describe it.

Answer 16

TRICUSPID VALVE (atrioventricular valve)

• has 3 cusps: anterior (the biggest), posterior and septum
• papillary muscles attached to cusps through chordaw tendinae

Question 17

Identify the structure A. What is its function?

Answer 17

TRABECULAE CARNAE: wall of ventricule that stops blood from pooling and coagulating in ventricule

Question 18

Identify all the valves in the heart and indicate what they separate.

Answer 18

(atrioventricular valves = A+B)

A: tricuspid valve : between right ventricule and right atrium

B: biscuspid valve or mitral valve: between left ventricule and left atrium

(semilunar valves= C+D)

C: aortic valve: goes to aorta (between left ventricule and aorta)

D: pulmonary valve : goes to pulmonary trunk (always anterior to C) (between right ventricule and pulmonary trunk)

Question 19

Explain the differences between semilunar valves and atrioventricular valves.

Answer 19

1. semilunar valves: do not have papillary muscles or chordae tendinae: allows blood to go out but when it contracts: prevents blood from going back into heart
2. atrioventricular valves: have chordae tendinae and papillary muscle: allows blood to go into ventricules (when relax): when contract, prevents blood from going out of ventricule

Question 20

Why is the left ventricule bigger thant eh right ventricule?

Answer 20

Because the left ventricule needs to pump blood to the whole body whilst the right ventricule only pumps blood to the lungs

Question 21

What is the ligamentum arteriosum?

Answer 21

ligamentum arteriosum is an embryological remnant of the ductus arteriosus

In fetus, blood that doesn’t travel through the foramen ovale (to go into the left ventricule for blood to go through the body) can return to the aorta due to a connection between the pulmonary trunk and aorta = ductus arteriosus

Post fetus: you don’t want deO2 blood to get into the aorta so the ductus arteriosus closes off and becomes the ligamentum arteriosum

Question 22

What is the landmark of the ligamentum arteriosum?

Answer 22

sternal angle: T4/T5 (manubriosternal joint)

Question 23

Explain the blood flow during diastole and systole for the heart. What causes the LUB sound? DUB?

Answer 23

Question 24

What are the landmarks of the heart? (4)

Answer 24

sternal angle (T4/T5): top of heart

xiphisternal joint (T9): bottom of heart

parasternal lines w xiphisternal: apex

midclavicular lines

Question 25

Idenitfy where you would measure each heart valve (stethoscope).

Answer 25

Valves are usually hidden behind bones => look where blood and sound flows to measure

DUB

1. Aortic valve: 2nd intercostal space @ right parasternal line
2. pulmonary valve: 2nd intercostal space, left parasternal line

LUB

1. tricuspid: fifth intercostal space: left parasternal line
2. bicuspid: 5th intercostal space: midclavicular line left