Thorax 3: The heart, internal structure and surface anatomy

Question 1

Name the layers of the heart and their functions

Answer 1

Myocardium - cardiac muscle
Endocardium - lines the chambers and valves
pericardium - simple squamous epithelium that secretes serous fluid

Question 2

What secretes serous fluid into the pericardial space

Answer 2

the squamous epithelium of the pericardium

Question 3

what brings deoxygenated blood into the right atrium?

Answer 3

IVC
SVC
coronary sinus

Question 4

Describe the direction of the outflow tract of the right atrium

Answer 4

the tricuspid valve faces anterior and medially to the left

Question 5

What is the purpose of musculi pectinati?

Answer 5

it roughens the wall of the right atrium from the crista terminalis into the auricle
this strengthens the walls of the right atrium without thickening it

Question 6

What is the crista terminalis?

Answer 6

the boundary between the rough and smooth walls of the right atrium

Question 7

What forms the posterior wall of the atria

Answer 7

the interatrial septum

Question 8

Where is the SA node located

Answer 8

close to the opening of the SVC on the superior side of the crista terminalis

Question 9

Where is the AV node located

Answer 9

on the septum between the opening of the coronary sinus and tricuspid valve

Question 10

describe the outflow tract of the right ventricle

Answer 10

up and backwards via the infundibulum to the pulmonary trunk

Question 11

what is the role of the infundibulum

Answer 11

Smooth part of the wall to create laminar flow

Question 12

What roughens and strengthens the walls of the ventricles

Answer 12

Trabeculae carne

Question 13

what is the septomarginal trabecula?

Answer 13

part of the trabeculae carne that bridges the anterior papillary muscle with inferior portion of the interventricular septum

Question 14

describe the shapes of the ventricles

Answer 14

the right is crescent shaped and the left is round due to the bulge in the interventricular septum

Question 15

how many cusps do each papillary muscle send chordae tendinae to?

Answer 15

2

Question 16

what links the pulmonary artery and the arch of the aorta

Answer 16

ligamentum arteriosum

Question 17

what is the relation of the pulmonary trunk to the aorta

Answer 17

posterior to aorta

Question 18

what are the 3 cusps of the pulmonary valve

Answer 18

anterior right and left

Question 19

what does competence of the mitral and tricupsid valves rely on

Answer 19

papillary muscles

Question 20

how many pulmonary veins are there?

Answer 20

4

Question 21

where are musculi pectinae found in the left atrium

Answer 21

left atrium

Question 22

what is found posterior to the left atrium?

Answer 22

oesophagus and descending thoracic aorta f

Question 23

what makes up the intraventricular wall of the left ventricle?

Answer 23

membranous and muscular portions from 4 embryological regions

Question 24

what is special about the right and left aortic cuspids

Answer 24

they contain sinuses that form the opening of the coranory arteries

Question 25

what is the cardiac skeleton?

Answer 25

it is a fibrous right that supports the valves and myocardium

Question 26

what is the purpose of the cardiac skeleton

Answer 26

it separates electrically the myocardium of the atria and the ventricles to prevent the spread of the impulse between them

Question 27

what is the only point of conduction between the atrium and ventricles?

Answer 27

AV Bundle of His

Question 28

What happens during systole

Answer 28

the atria relax and fill with blood ventricles contact and force blood out mitral and tricuspid valves close

Question 29

what causes the first heart sound

Answer 29

closure of the mitral and tricuspid valves during systole

Question 30

what happens during diastole

Answer 30

AV valves open and ventricles relax and fill with blood passively Atria contact aortic sinuses fill as blood falls back against the aortic valve

Question 31

what causes the second heart second

Answer 31

closure of aortic and pulmonary valves during diastole

Question 32

what causes an extra heart sound

Answer 32

calcification of aortic and pulmonary valves

Question 33

where would you listen to the aortic valves

Answer 33

2nd right intercostal space

Question 34

where would listen to pulmonary valves

Answer 34

2nd left intercostal space

Question 35

where would listen to tricuspid valves

Answer 35

4/5th interspace left

Question 36

where would listen to mitral flow

Answer 36

5th left interspace mid clavicular line

Question 37

what are the 4 corners of the heart?

Answer 37

2nd left CC 3rd Right CC 6th Right CC 5th left interspace