Cardio pt 2- Exam 2 Flashcards
What is the Fick equation?
VO2= CO * a-VO2 difference
In 100ml of body, what is your oxygen carrying capacity?
20mL
VO2 stands for?
oxygen consumption
When the arterial blood enters the tissue it has _____ oxygen. When the blood leaves the tissue it is at ___ oxygen.
20mL
15mL
tissue takes up 5mL of blood
In one minute, how much can your heart pump out?
5000 mL of blood
What is the total cardiac output?
25 Liters
25,000mL
What is stroke volume?
amount of blood that comes out of the heart per beat
T/F: Max heart rate can increase with exercise.
FALSE
max heart rate is a function of age
Chronotropic is defined as ?
how fast/slow the heart is beating
aka heart rate
Ionotropic is defined as ?
how hard the heart is beating
Stroke volume (increases/decreases) with fitness
increases
RESTING heart rate (increases/decreases) with fitness
decreases
Name some ways that stroke volume will increase?
Sympathetic nervous system, B-adrengeric stimulation, increase calcium -> harder the heart will contract
Oxygen is extracted by the _____ in the cells
mitochondria
Increasing calcium with (increase/decrease) heart contractility
increase (the force with which it contracts)
B adrenergic stimulates the SA node causing ??
increase the number of times the heart contracts
The a to VO2 difference will be (higher/lower) when you are fit
HIGHER because more oxygen is being used up in the tissues
aka the difference will be greater
What is training doing to your body to make the a to VO2 difference to increase?
the mitochondria are getting bigger and multiplying
more capillaries
higher stroke volume
sympathetic/parasympathetic is dominate at rest, what happens to your heart rate?
para
para stimulation will decrease the HR
what defines an efficient heart?
pumping the same amount of blood in less time
Name some factors that will affect preload
Name some factors that will affect afterload
Shoveling snow (static work)
What is the pressor reflex? What happens to BP and HR?
high amount of muscle tension increases cardiovascular function
both will increase
_____ in the carotid bodies of the aorta arch determines how much pressure inside the vessel
baroreceptors
What is the job of the baroreceptors?
to maintain normal blood pressure
In orthostatic hypotension the ____ are not picking up your blood pressure is low
baroreceptors
Before you even start working out, ____ _____ increases heart rate and pressure
Central command
the higher brain centers
through the sympathetic nervous system
______ initiates the cardiac cycle, how many times a minute?
SA node, 100
Due to ____ _____, if 1 heart cell fires off, they all fire off
inter-calculated discs
Where is the SA node located?
Superior lateral wall of the right atrium near the opening of the superior vena cava.
Why does AV node delays the impulse it receives from the SA node?
to give the ventricles time to fill
What is a PVC? What does it stand for?Why is it a problem?
When the heart fires off much lower than it is supposed to.
Preventricular Contraction
because the ventricle contracts an empty chamber
The electrical way goes what direction?
from the right shoulder to the left hip
During diastole, the _____ are relaxes and does what?
ventricles are relaxed and filling with blood
During systole, what valves are closing? describe the pressures in the atrium and ventricle
AV valves
pressure in the atrium is LESS than in the ventricle
pressure in the ventricle is GREATER than in the atrium
During diastole, what valves are closing? describe the pressures in the artery and ventricle
Semilunar valves
Pressure in the ventricle is LOWER than the artery
Pressure in the artery is GREATER than the ventricle
What 2 factors determine what the valves of the heart are doing?
Pressure and shape
What is the job of the chordae tendineae?
the maintain the shape of the valve
NOT TO OPEN/CLOSE THE VALVE
S1 is the sound of ?
closing of the mitral/bicuspid and tricuspid valve
S2 is the
closing of the semilunar valves
Describe what is happening in the period of rapid filling?
What curve will rise?
Moderately increased pressures have developed in the atria during ventricular systole immediately push the A-V valves open
LV volume curve
Describe what is happening in Isovolumic contraction
Immediately after V contraction begins, V pressure rises abruptly
AV valves close
Then an additional .02 - .03 seconds is required for the ventricle to build up sufficient pressure to push the semilunar valves open against the pressures in the aorta and pulmonary artery.
No emptying
During the period of ejection the left ventricle pressure is _____?
slightly above 80mmHg
During the period of ejection the right ventricle pressure is _____?
slightly above 8 mmHg
During the ____ period of ejection, _____% of blood is emptying is occurring during the first 1/3 of ejection
Rapid
70%
During the ____ period of ejection, _____% of blood is emptying is occurring during the 2/3rd of ejection
Slow
30%
During isovolumic relaxation, what is happening?
-Both the right and left INTRAVENTRICULAR PRESSURES decrease rapidly
-Distended large arteries that have been filled push blood back toward the V
-This snaps the aortic and pulmonary valves closed
-For another .03 to .06 second – the V muscle continues to relax – even though the ventricular volume does not change
What is stroke volume in terms of End Diastolic and End Systolic volume?
EDV- ESV = Stroke volume
What is ejection fraction?
the amount of blood that was actually pumped out of the ventricle compared to the total amount of blood in the ventricle
What is the formula for ejection fraction?
EDV-ESV/ EDV *100
Describe lamina blood flow
blood flowing like a bullet
this is the normal kind you want
Describe turbinent blood flow
blood that is bouncing off the walls of the vesells, NOT traveling in a straight line
Would aortic regurgitation be a preload/afterload stress?
preload because blood is going back into the heart
Would aortic stenosis be (preload/afterload) stress?
Afterload because blood is leaving the heart
Would mitral stenosis be (preload/afterload) stress?
not really either, decreasing preload a little bit
For the Volume-Pressure diagram, if the heart is under a PRELOAD stress it will shift and extend to the ____? The stroke volume will (decrease/increase)
to the right
increase
For the Volume-Pressure diagram, if the heart is under an AFTERLOAD stress it will shift ____?
Vertical, because the isovolumetric contraction will be higher to get the aortic valve to open
If the heart ejects more blood out in one pulse, than it did in the previous pulse you would say the contractility of the heart (increased/decreased)
increased
EW on the volume pressure diagram is ?
How hard the heart has to work
At rest, the heart consumes about ____ of the oxygen it receives from blood flowing through the coronary arteries,
70%
know how to draw this
just do it
The _____ can increase 4X from rest to maximal exercise in an adult without disease (from 250 ml/min to 1000 ml/min)
coronary blood flow
The rate pressure product is ??
SBP * HR
True/False: Every organ can control its own blood flow
True
What two organs receive the most blood per weight of the tissue?
Liver and Kidneys** the most
Describe redistribution of blood
blood goes to the areas that are currently being used the most
goes to muscles during exercise
goes to the GI after a meal
goes to the skin when needed to help regulate body temperature
What is an acute control of blood flow?
vasodilation/constriction of the arterioles, metarterioles and pre-capillary sphincter
What is a long term control of blood flow?
angiogensis
What is vasodilator theory?
The greater the rate of metabolism or the less the availability of oxygen or some other nutrients to the tissue, the greater the rate of formation of vasodilator substances in the tissue cells
The vasodilator substances then are believed to diffuse through the tissues to the pre-capillary sphincters, metarterioles, and arterioles to cause dilation.
In blood flow, the diameter of the vessel, is (not/very) influential
VERY influential, to the 4th power!
what does the macula densa do?
detects the composition of fluid in the early distal tubule, located on the distal tubule itself
What is the juxtaglomerular apparatus
process in which the kidney makes sure it gets enough blood flow so that it can filter the blood for the rest of the body
What is nitric oxide synthesized from?
Arginine and oxygen
Is NO made on demand or stored?
made when it is needed, NOT STORED
______ plays a role in the long term regulation of blood flow
oxygen
How do you calculate blood pressure?
Cardiac output * Total Peripheral Resistance
How do you calculate Mean Arterial Pressure?
Diastolic BP + (1/3 (Stystolic- Diastole BP))
Mean arterial pressure is used to??
calculate tissue perfusion
What is pressure difference?
difference of the blood between the two ends of the vessel
Describe vascular resistance
the impediment to blood flow through the vessel
Turbulent flow puts you at a higher risk for _____
blood clots
How do you calculate pulse pressure?
Systolic - diastolic
Is delta P proportion to flow or inverse to flow?
The diastolic BP does not change while doing what kind of movements?
steady, free flowing movements (Walking, cross country skiing)
The diastolic BP changes while doing what kind of movements? Why?
moving heavy things, weight lifting
when muscles bulge during static heavy work they put pressure on the vessels causing massive vasoconstriction
**The diastolic phase is a reflection of the ____ of the vessel
diameter
