Cardiophysiology

Question 1

When is cardiac pressure the highest in the ventricles?

Answer 1

When blood is being ejected into the aorta (ventricular contraction)

Question 2

What happens at the beginning and the end of a pressure loop in the ventricles?

Answer 2

Blood fills left atrium and mitral valve closes (passive ventricular filling)

Question 3

When does isovolumetric contraction happen? What is another name for it?

Answer 3

The time in between the mitral valve closing and the aortic valve opening

AKA systole

Question 4

When does isovolumetric relaxation happen? What is another name for it?

Answer 4

Between when the aortic valve closes and the mitral valve opens

AKA diastole

Question 5

What happens with pressure in relation to volume of blood flow through the ventricles in the heart?

Answer 5

As pressure rises, volume decreases

Question 6

What is the dicrotic notch?

Answer 6

When the aortic pressure is greater than the ventricular pressure

Question 7

In normal heart sounds, the “lub” is also called ? What does it represent?

Answer 7

S1 - represents the closing of the atrioventricular valves (i.e. tricuspid and mitral valve closing while pulmonic and aortic valve open)

ONSET OF VENTRICULAR CONTRACTION

Question 8

In normal heart sounds, the “dub” is also called? What does it represent?

Answer 8

S2 - represents the closing of the semilunar valves (i.e. pulmonic and aortic valve snap shut while mitral and tricuspid open)

ONSET OF VENTRICULAR RELAXATION

Question 9

What would you call an atrial gallop?

Answer 9

S4

Question 10

What would you call a ventricular gallop?

Answer 10

S3

Question 11

Due to a forceful atrial contraction in a stiff or hypertrophic ventricle

Answer 11

S4

Question 12

Can be associated with heart failure

Answer 12

S3 (ventricular gallop)

Question 13

How is coronary blood flow influenced if an individual has aortic regurgitation?

Answer 13

It is decreased

Question 14

How do you determine cardiac output?

Answer 14

Heart rate X stroke volume

Question 15

What is the max exertion of cardiac output?

Answer 15

20-25L/min

Question 16

How do you get a 4-5 fold increase in cardiac output?

Answer 16

Exercise

Question 17

How do you determine the appropriate maximum heart rate for a patient?

Answer 17

220-age

Question 18

How do you determine the maximum stroke volume if you are only given the age of an athlete?

Answer 18

Take the maximum cardiac output exertion (2500mL/min) and divide it by the maximum heart rate for that patient

Question 19

What are the physiological variables responsible for increasing cardiac output?

Answer 19

Increased heart rate and stroke volume

Question 20

What causes an increase in heart rate?

Answer 20

Decreased parasympathetic/increased sympathetic tone
Bainbridge reflex (atrial reflex)

Question 21

What causes an increase in stroke volume?

Answer 21

Increased sympathetic tone
Increased pre-load (VR) leads to an increase in contractility
Decreased arterial resistance (after load)

Question 22

What is after load?

Answer 22

Amount of pressure the heart has to overcome to get blood back to the rest of the body or to the lungs (resistance faced when letting go of slingshot)

Question 23

How is venous return increased? (Bainbridge reflex)

Answer 23

Skeletal muscle pump
Respiratory and abdominal pump
Venoconstriction from sympathetic tone

Question 24

The frank starling mechanism and bainbridge reflex mechanism are all what type of stroke volume control?

Answer 24

Intrinsic

Question 25

An increase in heart rate due to an increase in central venous pressure from increased venous return

Answer 25

Bainbridge reflex

Question 26

What is stroke volume?

Answer 26

Volume of blood ejected from the heart/heartbeat

Question 27

Increased venous return causes ???

Answer 27

Increased heart rate (bainbridge reflex)

Question 28

Increased end-diastolic volume causes ???

Answer 28

Increased contractility (frank-starling mechanism)

Question 29

What is extrinsic control of stroke volume

Answer 29

Increased sympathetic activity (and epinephrine) cases an increase in venous return and increased strength of cardiac contraction, leads to an increase in stroke volume or vice versa

Question 30

Does sympathetic stimulation affect the frank-starling curve?

Answer 30

Yes. A frank-starling curve on sympathetic stimulation will have an increased stroke volume when compared to a normal frank-starling curve at the same end-diastolic volume

Question 31

The percent of blood that is being ejected from the ventricle per beat

Answer 31

Ejection fraction

Question 32

How do you determine ejection fraction?

Answer 32

Need to measure EDV and ESV

Question 33

How do you assess ejection fraction?

Answer 33

Nuclear imaging, MRI, Echo, CT, Cardiac catheterization

Question 34

What is the equation for ejection fraction?

Answer 34

EF = (EDV-ESV/EDV) x 100

Question 35

How do you measure the extent of a patient's MI?

Answer 35

Ejection fraction

Question 36

What is a normal ejection fraction?

Answer 36

55-70%

Question 37

What is an ejection fraction that is below normal?

Answer 37

40-55%

Question 38

What ejection fraction may confirm a diagnosis of heart failure?

Answer 38

Less than 40%

Question 39

Fight or flight uses what system

Answer 39

Sympathetic - increases rate and force of contraction!

Question 40

Rest and digest uses what system

Answer 40

Parasympathetic - decreases rate and force of contraction

Question 41

What is essential for coronary blood flow?

Answer 41

Has to meet oxygen demand Oxygen supply = oxygen demand

Question 42

Oxygen extraction is near _____ at rest

Answer 42

Maximal

Question 43

What happens when the body needs more oxygen for metabolic activity?

Answer 43

Available O2 decreases, adenosine increases, and Co2 increases

Question 44

What happens when available O2 decreases, adenosine increases, and Co2 increases

Answer 44

Vasodilation of coronary vessels due to endothelial derived releasing factor Increased vasodilation due to increased nitrous oxide (shear stress) and decreased O2

Question 45

What happens when the coronary vessels vasodilate

Answer 45

Increased blood flow to cardiac muscle cels, increased oxygen available to meet oxygen needs!

Question 46

Atherosclerosis ____ blood flow

Answer 46

Compromises

Question 47

Large MI's can lead to ??

Answer 47

Chronic heart failure

Question 48

What causes problems during heart failure?

Answer 48

Depressed contractility that leads to decreased end diastolic volume and stroke volume

Question 49

How does the body compensate for a decreased cardiac output in a patient with heart failure?

Answer 49

Increased sympathetic activity: Increased venous return (increased end diastolic volume) and increased strength of cardiac contraction increases stroke volume and CO!

Question 50

What happens if one's resting CO cannot be attained?

Answer 50

Fluid imbalance because you cannot reach the critical cardiac output level for normal fluid balance

Question 51

What are some common medications to treat CHF?

Answer 51

``` Diuretics ACE/ARBs Vasodilators Beta Blockers Cardiac Glycosides ```

Question 52

Stage 1 heart failure

Answer 52

Mild weakness doesn't affect daily tasks

Question 53

Stage 2 heart failure

Answer 53

More than usual tiredness after performing daily exercise

Question 54

Stage 3 heart failure

Answer 54

Excessive fatigue after performing daily tasks

Question 55

Stage 4 heart failure

Answer 55

Any physical activity causes discomfort

Question 56

What is normal right atrial pressure?

Answer 56

2-6mmHg

Question 57

What continues to drive blood toward arterioles during diastole?

Answer 57

Elastic recoil

Question 58

How do you determine pulse pressure?

Answer 58

SBP - DBP

Question 59

How do you determine mean arterial pressure?

Answer 59

Diastolic pressure + 1/3 pulse pressure OR Diastolic pressure + 1/3 (SBP-DBP)

Question 60

Parabolic, highest velocity in center (least resistance); lowest adjacent to vessel walls Will be quiet when listening with a stethoscope

Answer 60

Laminar blood flow

Question 61

Disoriented and non-parabolic; energy is wasted, thus more pressure required to drive blood flow Will be detectable and NOISY with a stethoscope

Answer 61

Turbulent blood flow

Question 62

Sounds associated with measuring blood pressure

Answer 62

Korotokoff sounds

Question 63

Korotkoff sound that is a loud or sharp tapping

Answer 63

Phase 1

Question 64

Korotkoff sound that sounds like a "swooshing tap"

Answer 64

Phase 2

Question 65

Korotkoff sound that sounds like loud knocking or crisp tapping

Answer 65

Phase 3

Question 66

Korotkoff sound that sounds muffled or like a dull thudding

Answer 66

Phase 4

Question 67

Korotkoff sound that is silent as cuff drops below diastolic pressure

Answer 67

Phase 5

Question 68

What influences arterial pulse pressure?

Answer 68

elasticity rigidity resistance

Question 69

What is an abnormal sound or a murmer? What causes it?

Answer 69

A bruit | Caused by some kind of an obstruction like an atherosclerotic plaque that causes reduced blood flow

Question 70

If you have increased resistance, you are going to have ____ pulse pressures

Answer 70

Decreased

Question 71

Increased contraction of the circular smooth muscle in the arteriolar wall, which leads to increased resistance and decreased flow through the vessel

Answer 71

Vasoconstriction

Question 72

Decreased contraction of circular smooth muscle in the arteriolar wall, which leads to decreased resistance and increased flow through the vessels

Answer 72

Vasodilation

Question 73

Sympathetic tone usually causes ____? (vasoconstriction/vasodilation)

Answer 73

Vasoconstriction

Question 74

Parasympathetic tone usually causes ___? (Vasoconstriction/vasodilation)

Answer 74

Vasodilation

Question 75

Caused by increased myogenic activity, increased O2, decreased CO2, increased sympathetic stimulation Vasopressin, angiotensin II, COLD

Answer 75

Vasoconstriction

Question 76

Caused by decreased myogenic activity, decreased O2, increased CO2, and decreased sympathetic stimulation Histamine release, HEAT

Answer 76

Vasodilation

Question 77

It is important that blood flow matches ?

Answer 77

Metabolic need of tissue

Question 78

What causes vasodilation within local control?

Answer 78

Sympathetic cholinergic reflex

Question 79

Lack of nitric oxide release is reflective of ____?

Answer 79

Endothelial dysfunction (inhibited flow mediated dilation)

Question 80

What could cause a resistance of blood flow?

Answer 80

Viscosity, length of the blood vessel, diameter of the blood vessel (4th power)

Question 81

Veins have high _____

Answer 81

Capacitance (compliance)

Question 82

What increases venous return?

Answer 82

Sympathetic venoconstriction Skeletal muscle pump Respiratory pump Increased blood volume

Question 83

What decreases venous return?

Answer 83

Hydrostatic pressure due to gravity Incompetent venous valves Decreased pressure gradient

Question 84

Venous return affects cardiac ____

Answer 84

Preload

Question 85

Why is the velocity of blood flow through capillaries slow?

Answer 85

TO allow exchange due to a large cross-sectional area

Question 86

The total blood flow throughout your body is ____

Answer 86

Constant

Question 87

The velocity of your blood depends on the ??

Answer 87

Cross-sectional area Faster in river (aorta) than lake (capillaries)!

Question 88

How do you increase its metabolic activity?

Answer 88

Decrease O2, increase CO2 and other metabolites This will increase blood flow

Question 89

What forces favor filtration

Answer 89

Capillary hydrostatic pressure | Interstitial/tissue oncotic pressure

Question 90

What forces favor reabsorption?

Answer 90

Plasma oncotic pressure | Interstitial/tissue hydrostatic pressure