Week 1 CV

Question 1

What is the primary role of the cardiovascular system?

Answer 1

to transport nutrients to the body’s cells and remove waste products away from the cells
it regulates temperature, acid-base balance and the amount of fluid in the body

Question 2

what is the role of each part of the cardiovascular system?
(heart, arteries, capillaries, and veins)

Answer 2

heart = pump
arteries = distribution system
capillaries = where the transactions or exchanges take place
veins = collection and return system

Question 3

what does each side of the heart do?

Answer 3

right = receives blood from the body and brings it to the lungs
left = receives blood from the lungs and pumps it to the body

Question 4

what is the order of flow through the heart?

Answer 4

system -> vena cava -> right atrium -> tricuspid valve -> right ventricle -> pulmonary valve -> pulmonary artery -> lungs -> pulmonary vein -> left atrium -> mitral valve -> left ventricle -> aortic valve -> aorta -> system

Question 5

what do the lub and dub of the heart beat represent?

Answer 5

lub = tricuspid and mitral valve closing
dub = pulmonary and aortic valve closing

Question 6

what are the differences between the artery and veins?

Answer 6

arteries = have thicker muscular and elastic walls to handle higher blood pressures and volume leaving the heart
veins = thin walls and lower blood pressure further away from the pump. have valves that help prevent back flow

Question 7

what is the role of capillaries?

Answer 7

they are microscopic vessels between the arteries and veins whose walls only contain one layer of epithelial cells.
the walls allow blood cells to travel single file through them exchanging nutrients and waste between the blood stream and tissues

Question 8

what does muscle pumping do for venous return?

Answer 8

prevents pooling and edema
directs blood back towards the heart

Question 9

T/F: veins hold 65% of blood at rest

Answer 9

true

Question 10

what is a varicose vein?

Answer 10

when a one-way valve becomes defective in the vein and leads to the pooling of blood
usually effects surface veins due to less musculature to help compress the vessels

Question 11

what is phlebitis?

Answer 11

varicose veins with inflammation

Question 12

what is isovolumetric relaxation?

Answer 12

when all four valves of the heart are closed

Question 13

in relation to blood pressure what is systole?

Answer 13

when the aortic valve is open
the contraction phase
highest pressure
used to estimate work of heart
pumping into the system

Question 14

in relation to blood pressure what is diastole?

Answer 14

when the aortic valve is closed
the relaxation phase
indicates peripheral resistance
the filling of the pump

Question 15

what happens to blood pressure when a person has atherosclerosis or hardening of the arteries?

Answer 15

both systolic and diastolic BP increase due to the increased resistance, decreased elasticity, and endothelial dysfunction (vessel tone)

Question 16

what is considered normal blood pressure?

Answer 16

either or
<120 systolic
<80 diastolic

Question 17

what is considered hypertension blood pressure?

Answer 17

either or
>135 systolic
>85 diastolic

Question 18

what are some treatments for hypertension?

Answer 18

-medications that decrease contractibility
-regular physical activity
-weight loss due to the decrease in the amount of tissue the heart has to supply decreasing stress on the heart
-stress management
-decreased sodium intake and decreased alcohol consumption due to the changes in osmolality of the blood and the amount of fluid in the cardiovascular system

Question 19

what is the BP response to resistance exercise?

Answer 19

causes and increase in both systolic and diastolic BP due to straining

Question 20

what happens to systolic pressure with steady rate exercise?

Answer 20

increases with increasing workload
increases quickly initially then there is a linear relationship between workload and systolic BP

Question 21

what happens to diastolic pressure with steady rate exercise?

Answer 21

remains fairly constant

Question 22

why does the diastolic blood pressure stay the same as exercise intensity increase?

Answer 22

more muscle fibers are active, more oxygen and blood supply is needed, vasodilation and closed precapillary sphincters open increasing blood flow surface area

Question 23

what happens to BP during exercise recovery?

Answer 23

-following endurance exercise, there is a hypotensive response
BP temporarily falls below normal resting values

Question 24

what is BP’s response to upper body exercise?

Answer 24

resistance to flow is increased
smaller vessels in the upper body compress more easily (needs higher pressure to push blood through)
blood pressure increases substantially more with the same workload

Question 25

when is the heart supplied with blood?

Answer 25

when the aortic valve closes

Question 26

T/F: the heart can work anaerobically

Answer 26

no it needs oxygen

Question 27

at rest, what percentage of available O2 does the myocardium extract?

Answer 27

~70-80%

Question 28

during exercises flow must increase to meet the O2 demand. how much does it usually increase?

Answer 28

4-6 times

Question 29

the myocardium has a significantly higher mitochondrial density compared with skeletal muscle. this allows the heart to utilize:

Answer 29

glucose, fatty acids, and lactate (coming from working muscle)

Question 30

how does endurance exercise effect myocardial metabolism?

Answer 30

it increased the ability to use lactate and fatty acids for fuel. it increase mitochondria and aerobic enzymes results in decreased reliance on carbohydrates

Question 31

what is myocardial infarction?

Answer 31

death of the myocardium results from impaired blood supply

Question 32

what is the rate pressure product?

Answer 32

an estimate of myocardial work = SBP x HR

Question 33

what are the differences in cardiac muscle compared to other types of muscle?

Answer 33

it is striated contains intercalated discs that allow the electrical signal that causes contraction to spread across the myocardium in a specific manner resulting in coordinated contraction

Question 34

what is the path of depolarization of the heart?

Answer 34

-impulse spreads from the SA node throughout both atria -reaches the AV node which delays the spread of the impulse and allows time for efficient blood flow -travels into the left and right bundle branches then into the perkinje fibers

Question 35

what does an EKG do?

Answer 35

records the signal of the heart depolarizing

Question 36

what does each part of the EKG represent? (P wave, QRS complex, T wave)

Answer 36

p wave = depolarization of the atria QRS complex = depolarization of the ventricles T wave = repolarization of the ventricles as they recover from muscle contraction

Question 37

what is intrinsic regulation of heart rate?

Answer 37

inherent rhythm of the SA node (in a closed system ~100 BPM)

Question 38

what is extrinsic regulation of heart rate?

Answer 38

neural: direction innervation chemical: circulate via blood

Question 39

what are the two extrinsic influences on BP?

Answer 39

sympathetic and parasympathetic

Question 40

how does sympathetic affect the heart?

Answer 40

increases the work of the heart catecholamines: chronotropic increase the rate, inotropic increase contractility adrenergic fibers: key for smooth muscle tone

Question 41

how does parasympathetic affect the heart?

Answer 41

the relaxation response slows the heart rate vagus nerve: cholinergic fibers release ACh, which slows HR as exercise begins there is a decrease in parasympathetic activity

Question 42

what determines the amount of blood flow?

Answer 42

the pressure differential from the beginning of the system to the end

Question 43

what is the equation for blood flow?

Answer 43

pressure gradient x vessel radius4 / vessel length x viscosity

Question 44

what can cause vasodilation?

Answer 44

temperature, CO2, pH, NO

Question 45

what can cause vasoconstriction?

Answer 45

epinephrine and norepinephrine

Question 46

what is nitric oxide?

Answer 46

produced and released by the vascular endothelium causes relaxation of the smooth muscle and results in vasodilation

Question 47

what is cardiac output?

Answer 47

volume of blood pumped in 1 minute Q = HR x SV

Question 48

what factors affect cardiac output (Q)?

Answer 48

venous return (amount of blood returning from the body) diastolic filling (how much blood is in the heart chamber before contraction) strength of contraction parasympathetic nervous systems (slows HR) mean arterial blood pressure

Question 49

what is MAP and what is it used for?

Answer 49

mean arterial pressure: the amount of blood that is getting to the body used to monitor perfusion of organs

Question 50

what is normal MAP?

Answer 50

70-110 (need 60 to perfuse organs)

Question 51

how is Q increased?

Answer 51

increasing preload, contractility and volume

Question 52

what is preload?

Answer 52

pressure in the venous system that stretched the myocardium

Question 53

what is ejection fraction?

Answer 53

the amount of blood ejected by the left ventricle during systole total volume ejected by LV / amount left in LV stroke volume / end diastolic volume

Question 54

what is normal ejection fraction (EF)?

Answer 54

> or equal to 55-75%

Question 55

what is EF in CHF?

Answer 55

~20%

Question 56

what is dehydrations effect on Q?

Answer 56

leads to lower blood volume because of lower fluid. it decreases Q

Question 57

what is the difference in cardiac output between men, women and children?

Answer 57

women have 10% lower hemoglobin level than men which results in 5-10% larger Q to compensate children have a smaller volume

Question 58

what is the a-vO2 difference?

Answer 58

the amount of oxygen that is extracted from the blood

Question 59

what is normal a-vO2 difference during rest?

Answer 59

20 ml O2 * dl-1 arterial 15 ml O2 * dl-1 venous

Question 60

what is normal a-vO2 difference during exercise?

Answer 60

20 ml O2 * dl-1 arterial 5-15 ml O2 * dl-1 venous

Question 61

what is the V02 equation?

Answer 61

Q x a-vO2 difference

Question 62

what factors affect the a-vO2 difference?

Answer 62

-redistribution of flow to active tissues during exercise -increased capillary density due to training increase surface area and O2 extraction -increased number and size of mitochondria -increased oxidative enzymes -vascular and metabolic improvements

Question 63

how is the distribution of blood directed?

Answer 63

vasodilation and vasoconstriction

Question 64

what is the difference between VO2max and VO2peak during aerobic or long term energy system?

Answer 64

VO2max = O2 consumption levels off despite an increase in exercise intensity, has been reached VO2 peak = highest value of oxygen consumption measured during graded test exercise

Question 65

what are the commonly used VO2max prediction tests?

Answer 65

walking tested - Reebok 1-mile endurance runs - cooper test step tests 2 or 6 min walk test

Question 66

what is the resting value for cardiac output?

Answer 66

~5.0 L/min

Question 67

cardiac output increases with increasing exercise intensity up to:

Answer 67

~20 to 40 L/min

Question 68

how does VO2 differ with upper body exercises?

Answer 68

higher VO2 at given submax workload but max VO2 is ~20-30% lower than w/ LE exercises

Question 69

submaximal arm exercise produces a greater:

Answer 69

HR pulmonary ventilations RPE BP response than comparable leg exercises

Question 70

what is the effect of a cardiac transplant on HR response?

Answer 70

HR response is blunted with transplant