Organization of the Cardiovascular System: Dr. Wilson Flashcards
What system is the primary limiting factor whether young or old?
muscular system
What are the functions of the cardiovascular system?
1) gas exchange
2) nutrients
3) removal of wastes
d) protective cells and proteins
e) regulatory proteins
f) heat
Is heat a waste product?
YES, it is an important waste product that needs to be rid of if it is excess in the body.
CV diseases often affect all systems. Explain.
- because the CV system comes into contact and interacts with most of the cells of the body, CV diseases often affect all systems
- if you have disease of other organ systems it will also affect the CV system
At day 25 of embryo development, what is the first system to function?
Cardiovascular system
the heart begins to beat
The heart, vessels, and blood develop from what embryological origin?
mesoderm
Define ischemia, hypoxia, and anoxia.
Ischemia = mechanical obstruction of blood supply (deprive tissue of O2, nutrients and allow waste products to build up)
hypoxia = decreased levels of oxygen
anoxia: no oxygen
Hypoxia and anoxia are a consequence of ischemia
Define infarct.
an area of necrosis resulting from inadequate blood flow
The CV system is organized into what two closed loops?
- pulmonary loop (to lungs, gas exchange)
- systemic loop (to tissues, organs, and glands: exchange of nutrients and waste)
The pulmonary system supplies what tissues in the lungs?
alveoli (capillaries)
It is estimated that the body has 60,000 miles of blood vessels. Most of the body’s vessels are found in what system, pulmonary or systemic?
Most found in the systemic system
systemic: 59,000 vessels
pulmonary: 1,000 vessels
Which system presents the greatest resistance to blood flow? Has the highest blood pressure?
systemic system has the greatest blood flow and the highest pressure
-takes a lot of force and energy to pump blood to the whole body (this system supplies the heart, brain, muscles, skin, kidneys, and other orgas, glands, and tissues of the body) as opposed to one pulmonary organ (lungs)
Which side of the heart pumps blood through the pulmonary loop?
right side of heart
Which side of the heart pumps blood through the systemic loop?
left side of heart
Why is the left heart thicker than the right? Explain in terms of load.
Muscles hypertrophy when given load.
The load for pumping blood through the systemic system is higher due to higher resistance, therefor the left ventricle has to pump harder to get enough blood through the aorta to supply the body = thicker walls
Which side of the heart has higher cardiac output?
both the right and left heart must be EQUAL in cardiac output
What are other mechanisms for pumping blood besides the heart?
respiratory pump
muscle pump
How does the respiratory pump work to pump blood?
contraction of the diaphragm pumps blood into the right atrium by:
1) decreasing thoracic pressure
2) increasing abdominal pressure
3) opening up the IVC
How does the muscle pump work to pump blood?
contraction of the calf muscles helps to bring blood back to the heart with the help of one way valves ensuring unidirectional flow of the blood
Most veins have valves. What is the function of valves?
valves allow for unidirectional flow of blood towards to the heart
How does pressure affect blood flow?
the more pressure the heart produces the greater the blood flow
REMEMBER: the anatomical factor that affects flow is pressure)
Pressure =/~ flow
How does resistance affect blood flow?
blood flow is inversely proportional to resistance; the greater the resistance the lower the blood flow
Flow = 1/ Resistance
What causes resistance in the blood vessels?
Friction between blood and the walls of blood vessel
- resistance is irreversely proportion to (radius)4
- the greater the radius the lower the resistance
- when arteries get clogged up your resistance to blood flow goes up
Resistance = 1/r4
How does atherosclerosis affect resistance and flow turbulence?
- it increases resistance and flow turbulence
- it is going to take more pressure to deliver the same amount of blood to the tissues distal to the plaque
What are the 9 common sites to take pulse?
- superficial temporal
- facial
- common carotid
- brachial -radial
- femoral
- popliteal
- posterior tibial
- dorsalis pedis
If the pulse is not symmetrical on both sides what does this mean?
this could be a sign of vascular disease
To offset a 16 fold increase in resistance, pressure must be increased by 16 times. What does this mean?
- the heart has to work harder
- muscles hypertrophy when you put more load on them
Hypertrophy of the left ventricle occurs due to hypertension. How much can the left heart increase in size?
- the heart will hypertrophy until it fails
- if you cannot compress the lumen, the blood will not be able to go out and thus tissues will not receive oxygen
Increased vascular resistance due to emphysema affects what side of the heart?
right side of heart as this is a problem with pulmonary circulation
On a chest xray how do we classify a hypertrophied heart?
when the heart has taken 1/2 the diameter of the diaphragm
How does an aneurysm result?
- when the pressure in a vessel exceeds the elastic components of the tunics
- pressure causes the walls of blood vessels to weaken (bulging of the artey)
- can be caused by high BP
When an aneurysm ruptures, what does it produce?
hemorrhaging stroke