EXPH 386 exam 4

oxygen, fuel, nutrients

what does the cardiovascular system deliver to the active tissues?

deoxygenated blood

what does the cardiovascular system return to the lungs?

heat

what does the cardiovascular system transport from the body's core to the skin?

hormones

what does the cardiovascular system transport to the body's chemical messengers?

dual

what kind of pump is the heart?

pulmonary and systemic

what are the two blood flow circuits?

pulmonary circulation

between the heart and the lungs

systemic circulation

between the heart and other body systems

oxygenated, body, deoxygenated

systemic circulation is the portion of the CV which carries _______ blood away from the heart, to the ______, and returns ______ blood back to the heart

deoxygenated, lungs, oxygenated

Pulmonary circulation is the portion of the CV which carries _____ blood away from the heart, to the _____, and returns ______ blood back to the heart

veins to atria to ventricles to arteries

what is flow of blood through the heart?

heart valves

ensure that blood flows in the right direction through the heart

pressure

what differences causes valves to passively open and close?

pressure

what kind of gradient governs the passive filling of the ventricles?

active filling

atrial contraction

30%

at resting heart rates, what percent does the atrial contraction contribute to the filling of the ventricle?

70%

what percent of venous return enters the ventricle before the atria undergoes contraction?

lub

tricuspid and mitral valves snapshut and pulmonary and aortic open

dub

aortic and pulmonary snapshut and tricuspid and mitral valve open

isovolumetric contraction

for a brief period of time (0.02 to 0.06 sec), when all the heart valves remain shut, ventricular pressure rises but volume and fiber length remain unchanged

isovolumetric relaxation

for a brief period of time (0.02 to 0.06 sec), when all heart valves remain shut, ventricular pressure drops but volume and fiber length remain unchanged

arteries

thick walled, high pressure tubing that conducts oxygenated blood; have smooth muscle cells and endothelial cells

arterioles

smaller branched arteries, circular layers of connective tissue; constrict or relax changing the resistance to blood flow (aka resistance vessels)

capillaries

single layer of endothelial cells; no smooth muscle; diameter reduced to only allow 1 blood cell at a time; dormant capillaries open during exercise; local metabolites; blood cell takes approximately 1.5 seconds to pass

venules

small veins that collect deoxygenated blood from capillaries

veins

thin walled, lower pressure; also have smooth muscle cells and endothelial cells

capacitance vessels

act as a blood reservoir, holding 64% of blood volume

Venous return

The alternate compression and relaxation of veins and the one way action of their valves provide a milking action that propels blood back to the heart

Venous pooling

May induce fainting from insufficient cerebral blood supply

Active cool down

Moderate exercise in recovery facilities blood flow to the heart

Varicose veins

Veins fail to maintain their one way blood flow, blood gathers in veins and they become excessively distended and painful

Blood pressure

Force exerted by blood on the walls of blood vessels, and is one of the principal vital signs

CO*TPR

blood pressure formula

Decreases

What happens to blood pressure as the circulating blood moves away from the heart through arteries?

Arterioles and small arteries

Where does blood pressure have its greatest decrease?

Systolic blood pressure

Highest arterial pressure measured after left ventricular contraction

Diastolic blood pressure

Lowest arterial pressure measured during left ventricular relaxation

Mean arterial pressure

Average arterial pressure during a single cardiac cycle

93

What is the average mean arterial pressure at rest?

Perfusion pressure

What is mean arterial pressure considered when seen by organs in the body?

60 mmHg

lowest perfusion pressure possible for organs and tissues to function

Ischemic

Mean arterial pressure below 60 mmHg for an appreciable time the end organ will not get enough blood flow, and will become what?

120/80

What is normal blood pressure range?

SBP=120-129 DBP>80

What is pre hypertensive blood pressure range?

SBP=130-139 DBP>80

What is the blood pressure range for stage 1 hypertension?

Hypertension

Hardened arteries and neural hyperactivity cause increased resistance

SBP>140 DBP= 90-99

What is the blood pressure range for stage 2 hypertension?

SBP>180 DBP>100

What is the blood pressure range for a hypertensive crisis?

2 mmHg

How much does BP need to decrease to decrease death from stroke by 6% and heart disease by 4%

Dementia and cognitive impairment

If blood pressure decreases it prevents stroke and vascular disease and may decrease the progression of what?

Increases

What does blood volume do to blood pressure?

Increases

What does heart rate do to blood pressure?

Increases

What does stroke volume do to blood pressure?

Increases

What does blood viscosity do to blood pressure?

Increases

What does total peripheral resistance do to blood pressure?

Blood vessel diameter

What does the body use to help regulate blood pressure?

Decreases TPR and lowers BP

When BP is too high, blood vessels expand to allow more blood flow what happens to TPR and BP?

Increase TPR and BP

When BP is low, vessels constrict to do what to TPR and BP?

5 L/min

What is the CO at in a normal person at rest?

Cardiac output

The amount of blood that is ejected by one ventricle in a one minute period of time

Vasodilation

What happens in vessels to active muscles in steady rate exercise to decrease TPR and increase blood flow to the peripheral vasculature

Increases

Increase blood flow during steady rate exercise rapidly does what to SBP during the first few minutes of exercise?

Decreases

What happens to SBP as exercise continues because the arterioles continue to dilate?

Exercise intensity

SBP increases linearly with what?

Stable or decreases slightly

What happens to DBP with graded exercise?

Graded exercise

This level of BP most likely reflects the hearts large CO during maximal exercise by individuals with high aerobic capacity

Concentric

What type of contraction compressed peripheral vasculature causing an increase in TPR?

Maximal exercise

VO2 values for upper body exercise are typically 20 to 30% below those of lower body exercise, lower max HR and pulmonary ventilation, smaller musculature activated

Upper body exercise

What requires greater oxygen consumption at any given submaximal power output UBE or LBE?

UBE

Which provides greater physiological strain for any given submaximal power output LBE or UBE?

12

After a bout of sustained light to moderate exercise, SBP temporarily decrease below pre exercising levels for up how many hours in normal and hypertensive subjects?

Lower BP

Blood pools in skeletal muscle vascular beds during recovery and decreases central blood volume and decreased atrial filling pressure which will do what to BP?

>210

At peak exercise what is SBP for men?

>190

At peak exercise what is SBP for women?

>200

What is SBP at exercise workload of about 6 to 7 METs?

No

Are nutrients taken from the blood flowing to the heart chambers in coronary circulation?

5%

How much of total output does coronary circulation supply the heart muscle?

Myocardium

Arteries divide into a dense capillary network that feeds what?

70-80%

At rest the myocardium extracts how much of the oxygen from the blood flowing in the coronary vessels?

25%

Most other tissues only use approximately how much oxygen?

4-6 times

In vigorous exercise, coronary blood flow increases how much above resting level?

Aerobic

Cardiac muscle is purely what?

Chest pain

What is the result of blood flow is interrupted?

Stress test

Used as a diagnostic tool for myocardial blood flow

Myocardial infarction

A blood clot within coronary vessels results in what?

Necrosis

Cell death

Ischemia

A restriction in blood supply to tissues

Hypoxia

A region of the body is deprived adequate O2 supply

Infarction

Tissue death caused by a local lack of oxygen

rate pressure product

provides an noninvasive estimate of myocardial workload (myocardial oxygen uptake)

SBP*HR

what is rate pressure product equal (what is multiplied together)?

exercise intensity

what does RPP have a linear relationship with?

static exercise

greater increase in SBP than dynamic exercise and therefore higher myocardial workload than dynamic exercise

cardiac hypertrophy (angina)

chronic exposure to a higher myocardial workload can lead to what?

aerobic energy metabolism

what is cardiac energy supply almost exclusively?

fatty acids, glucose, lactate

what are the primary sources of energy for cardiac?

prolonged submax exercise

combination of glucose, fatty acids, and lactate supply what type of exercise?

maximal exercise

lactate is the main supply for what type of exercise?

100 bpm

without external stimuli, what is the intrinsic HR approximately?

40 bpm

the extrinsic control of the heart can adjust the HR how much at rest?