Cardiac Lecture 2

Question 1

What is Reynold’s number?

Answer 1

Theoretical number to calculate likelihood of turbulent flow

Question 2

What Reynold’s number is turbulent flow likely?

Answer 2

> 2000

Question 3

If blood vessel diameter increases, will turbulence increase or decrease?

Answer 3

Increase turbulence

Question 4

If blood velocity increases, will turbulence increase or decrease?

Answer 4

increase turbulence

Question 5

If blood density increases, will turbulence increase or decrease?

Answer 5

increase turbulence

Question 6

If blood viscosity increases, will turbulence increase or decrease?

Answer 6

decrease turbulence

Question 7

Which blood vessels are most prone to turbulent flow?

Answer 7

Aorta and large arteries

Question 8

Flow meter assesses blood flow by using an electromagnetic probe to measure the magnetic field produced by ______

Answer 8

iron in heme

Question 9

Phase 1 of the cardiac cycle occurs during

Answer 9

ventricular filling/diastole

Question 10

During phase 1, the mitral valve is ______ and the aortic valve is _______

Answer 10

mitral open, aortic closed

Question 11

During phase 2, the mitral valve is ______ and the aortic valve is _______

Answer 11

mitral closed, aortic closed

Question 12

During phase 3, the mitral valve is ______ and the aortic valve is _______

Answer 12

mitral closed, aortic open

Question 13

During phase 4, the mitral valve is ______ and the aortic valve is _______

Answer 13

mitral closed, aortic closed

Question 14

What do we call the amount of blood remaining at the end of systole, and how much is it?

Answer 14

End-systolic volume, 50mL

Question 15

What do we call the amount of blood in the ventricle at the end of filling, and how much is it?

Answer 15

End-diastolic volume, 120mL

Question 16

Normal stroke volume is ____ mL

Answer 16

70mL

Question 17

Atrial contraction provides what amount of end-diastolic volume, ____mL? (in healthy person)

Answer 17

10mL

Question 18

In heart failure, atrial kick provides ______ % of end-diastolic volume

Answer 18

> 25%

Question 19

Stroke volume = ______ - _________

Answer 19

stroke volume = end diastolic volume - end systolic volume

Question 20

At the beginning of phase 1, pressure in the left atria is greater or less than left ventricle?

Answer 20

LAP > LVP; that’s why the mitral valve opens

Question 21

Diastole is phase _____ of the cardiac cycle

Answer 21

1

Question 22

The mitral valve is also called the _______ valve

Answer 22

Bicuspid valve

Question 23

When LV pressure is > LA pressure the ______ valve will ________

Answer 23

mitral valve/bicuspid valve, close

Question 24

Interventricular volume does not change in which phases?

Answer 24

2 and 4

Question 25

phase 2 is also called ______ _______

Answer 25

isovolumetric contraction

Question 26

phase 4 is also called ______ _______

Answer 26

isovolumetric relaxation

Question 27

In phase 2 the ventricle is ______

Answer 27

beginning to contract

Question 28

Phase 2 ends when ______

Answer 28

Aortic valve opens

Question 29

Phase 3 is also the _____ _______ ______

Answer 29

period of ejection

Question 30

Phase 3 begins when ______

Answer 30

aortic valve opens

Question 31

Phase 3 ends when _____

Answer 31

aortic valve closes systemic pressure is > LV pressure

Question 32

Phase 4 begins when ______

Answer 32

aortic valve closes relaxation occurs without volume change

Question 33

Phase 4 ends when _____

Answer 33

mitral valve opens LA pressure is > LV pressure

Question 34

The diastolic blood pressure number is the pressure when _______

Answer 34

aortic valve opens

Question 35

For our class, diastole starts when ________

Answer 35

aortic valve closes (end of phase 3, start of phase 4)

Question 36

For our class, systole starts at ________

Answer 36

end of phase 1/start of phase 2, at end-diastolic volume

Question 37

The vast majority of ventricular filling occurs ______

Answer 37

early, first 1/3 of filling

Question 38

If the mitral (bicuspid) valve is stenotic, how will it affect LV filling?

Answer 38

filling will occur slower due to impedance of blood flow from LA to LV

Question 39

With mitral stenosis, you want the heart rate to be higher or lower?

Answer 39

Lower. Because slower LV filling, lower HR will give more time to fill

Question 40

1st heart sound is when ______

Answer 40

A-V valves close; tricuspid and mitral(bicuspid)

Question 41

2nd heart sound is when ______

Answer 41

aortic and pulmonic valve closes

Question 42

Aortic blood pressure is lowest at ____

Answer 42

end of phase 2

Question 43

Normal mean systemic filling pressure (Psf) is

Answer 43

+7 mmHg

Question 44

ΔP equals

Answer 44

Avg cv pressure - RA pressure normal ΔP = (7-0)=7

Question 46

reduction in RVR would _______ (increase/decrease) venous return and CO

Answer 46

increase

Question 47

increase in RVR would _______ (increase/decrease) venous return and CO

Answer 47

decrease

Question 48

Something that impedes blood from returning to the heart would _____ (increase/decrease) RVR

Answer 48

increase

Question 49

Low RVR would cause the slope on the venous return graph to be _______

Answer 49

steep

Question 50

High RVR would cause the slope on the venous return graph to be _______

Answer 50

less steep

Question 51

2 main factors that contribute to mean systemic filing pressure are

Answer 51

blood volume and venous tone

Question 52

What are the 3 factors that augment cardiac output when filling pressures increase

Answer 52

1. Frank Starling mechanism (cross bridge alignment, healthy heart under stretched at rest) 2. Direct atrial stretch: property of conduction system of the heart. If atria stretched, causes HR to increase by 10-15% 3. Bainbridge reflex: external reflex from heart to CNS and back to heart (through vagus nerve) to accommodate higher filling pressure. increases HR by 40-50%

Question 53

Direct atrial stretch does or does not rely on nerve activity to increase HR?

Answer 53

doesn't rely on nerve activity

Question 54

Both afferent and efferent parts of the Bainbridge reflex are carried by the _______

Answer 54

vagus nerve heart ---> vagus nerve --> brain stem --> inc. sympathetic output and decrease sympathetic output by vagus nerve