The Cardiac Cycle

Question 1

Draw the WIgger’s Diagram for the left atrium, ventricle, and aorta.

Answer 1

Question 2

left atrial a wave

Answer 2

contraction of the atrium (atrial kick) during atrial systole

Question 3

left atrial c wave

Answer 3

valve leaflets are moving back up into the left atrium when the ventricle contracts, leading to a rise in pressure in the atrium

Question 4

left atrial v wave

Answer 4

during ventricular ejection, blood continues to flow into the atria from the systemic and pulmonary veins while the AV valves are closed

this distends the atrial walls and causes a gradual rise in atrial pressure

a sharp fall occurs when the AV valves open at the onset of rapid ventricular filling

Question 5

normal human end diastolic volume

Answer 5

130 mL

Question 6

normal human end systolic volume

Answer 6

60 mL

Question 7

Draw the waveform of the jugular venous pulse.

Answer 7

Question 8

What is the normal stroke volume for a 70kg person?

Answer 8

75 mL

Question 9

What is the normal cardiac output?

Answer 9

5L/min

Question 10

incisura (dicrotic notch)

Answer 10

the result of the elastic recoil of aortic diameter back down from its temporarily expanded diameter caused by ventricular ejection

Question 11

diastasis (quiet period)

Answer 11

the period in late diastole where very little additional blood fills the ventricles

Question 12

jugular a wave

Answer 12

rise in pressure caused by atrial contraction

priminent a wave signifies right ventricular hypertrophy or tricuspid stenosis

Question 13

jugular c wave

Answer 13

rise in pressure caused by right ventricular contraction and movement of tricuspid valve into the right atrium

Question 14

jugular v wave

Answer 14

filling of the right atrium against a closed tricuspid valve

prominent v wave signifies tricuspid regurgitation

Question 15

jugular x descent

Answer 15

fall in atrial pressure that occurs as the ventricle ejects volume into the pulmonary artery

Question 16

jugular y descent

Answer 16

caused by the opening of the tricuspid valve

prominent y descent signifies constrictive pericarditis

Question 17

first heart sound S1

Answer 17

vibration caused by closing of the AV valves, mitral first then tricuspid

best heard at the apex “lub”

Question 18

Where is the mitral valve closing best heard?

Answer 18

to the left of the sternum (4th intercostal space)

Question 19

Where is the closing of the tricuspid valve best heard?

Answer 19

over the sternum

Question 20

second heart sound S2

Answer 20

closure o the aortic and then pulmonary valves

“dub”

Question 21

Where is the aortic component of S2 best heard?

Answer 21

to the left of the sternum at the first intercostal space

Question 22

Where is the pulmonic component of S2 best heard?

Answer 22

to the right if the sternum at the first intercostal space

Question 23

third heart sound S3

Answer 23

when the blood flows passively from the atria into the ventricles, it creates some turbulence, which if excessive, causes S3

this is not normally heard

Question 24

fourth heart sound S4

Answer 24

the additional spurt that can cause some turbulence when the atria contract

this is not normally heard

Question 25

Describe the timing of contraction, valve movements, and heart sounds.

Answer 25

Question 26

cadicac index (liters/min/sq m)

Answer 26

mean at rest: 3.1

range at rest: 2.5-4.0

Question 27

venous pressure (mmHg)

Answer 27

mean at rest: 5

range at rest: 3-8

Question 28

right atrial pressure (mean; mmHg)

Answer 28

mean at rest: 2

range at rest: -2 - +5

Question 29

right ventricular pressure (systolic; mmHg)

Answer 29

mean at rest: 25

range at rest: 18-30

Question 30

right ventricular pressure (end-diastolic; mmHg)

Answer 30

mean at rest: 2

range at rest: -5 - +5

Question 31

pulmonary artery pressure (systolic; mmHg)

Answer 31

mean at rest: 25

range at rest: 18-30

Question 32

pulmonary artery pressure (diastolic; mmHg)

Answer 32

mean at rest: 10

range at rest: 6-12

Question 33

pumonary artery pressure (mean; mmHg)

Answer 33

mean at rest: 15

range at rest: 10-20

Question 34

pulmonary wedge (mean; mmHg)

Answer 34

mean at rest: 6

range at rest: 0-12

Question 35

left atrial pressure (mean; mmHg)

Answer 35

mean at rest: 6

range at rest: 0-12

Question 36

left ventricular pressure (systolic; mmHg)

Answer 36

mean at rest: 120

range at rest: 100-140

Question 37

left ventricular pressure (diastolic; mmHg)

Answer 37

mean at rest: 6 mmHg

range at rest: 0-12

Question 38

brachial artery pressure (mean; mmHg)

Answer 38

mean at rest: 95

range at rest: 85-105

Question 39

right ventricular contraction

Answer 39

free wall shortens

free wall moves towards septum

septum moves towards free wall

Question 40

left ventricular contraction

Answer 40

chamber constricts

chamber shortens