Term
What is the arrangement of the Cardiovascular system? |
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Definition
There is a systemic and pulmonary circuits that is in series.
In the systemic circuit: The right side of the heart pumps blood to the lungs and the left side of the heart pumps blood to the systemic circulation. |
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Term
In the cardiovascular system the circuits of the organ systems are in _______________ which means that flow through these organs are _______________ of each other which ______________ the pressure. |
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Definition
parallel
are independent (better to have more paths)
decreases |
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Term
The ____________ has a greater pressure than the ___________. |
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Definition
Arteries has the highest
Then capillaries
Veins have the lowest |
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Term
In the systemic circuit the arteries have a pressure of ____ while the veins have a pressure of __________. |
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Definition
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Term
How is tension calculated? |
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Definition
(The pressure across the wall x radius)/ wall thickness
T = (Ptm x R)/ (M) |
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Term
Tension is greatest in _______ vessels so the ________ will have the greatest tension. |
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Definition
Big vessels that have a large diameter
Aorta |
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Term
Tension is least in small vessels with low pressure like in _____________. |
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Definition
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Term
Large vessels need _______ wall thickenss and structure than small vessels. |
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Definition
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Term
Pressure and volume in the heart are ______________ related so since the arteries have a higher P then you will have a __________ V than the veins. |
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Definition
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Term
If you have a thicker wall vessel then you tension is ________. |
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Definition
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Term
The arteries holds about _______ of the blood volume whereas the veins hold ________. |
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Definition
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Term
Arterties are made from ___________ and ___________ VSM and elastic fiber. |
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Definition
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Term
Elastic arteries are for _______________ whereas muscular arteries are used to ______. |
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Definition
Stretch and Recoil
Distribute |
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Term
Arterioles have less elastic fibers and longitudinal VSM than arteries so they have ____________ used for ___________. |
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Definition
Circular smooth muscle
resistance |
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Term
Main function for capillaries is for |
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Definition
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Term
Veins/venules have a high amount of ______________________ so it has _____________. |
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Definition
Longitudinal VSM
Compliance |
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Term
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Definition
Refers to the total quantity of blood that can be stored in a given portion of the circulation for each mm rise in pressure.
C= Volume change/ Pressure change |
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Term
Which vessel has the largest compliance and why? |
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Definition
Veins; because an increase in volume change only change the pressure a little bit. This allows them to act as a reservoir for storing large quantities of blood that can be returned to the circulation. |
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Term
What causes the flow of blood in the heart circuit? |
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Definition
A pressure gradient
From high pressure to a low pressure
from arteries to veins |
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Term
What is the physics behind the blood flow in the heart? |
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Definition
Ohm's Law
Flow = Q
Q = ΔP/R
where P = pressure
R= resistance to flow |
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Term
How do we calculate the resistance to blood flow in the heart? |
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Definition
R ∞ η/r4
So Resistance increases as the viscosity increases.
And if the radius was to increase, this will decrease the resistance by a factor of 10^4. |
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Term
To increase blood flow we want (narrower/wider) vessels. |
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Definition
Wider
If you increase r then you decrease the resistance. |
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Term
How do you calculate the change in pressure? |
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Definition
ΔP = Cardiac output x Total resistance
ΔP = P aorta - P Vena cava
ΔP = CO x TPR
(where TPR is the total peripheral resistance) |
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Term
If you want to increase the flow of blood to an organ you want to ____________ or ___________. |
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Definition
Increase the pressure in the arteries
or
decrease the resistance in the arteriole |
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Term
How does the heart do "work"? |
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Definition
By pumping a volume of blood against arterial pressure
if you increase either the pressure or volume pumped by the heart you have more work |
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Term
Arterioles get smaller in size as they branch further into tissues. This leads to ___________ . |
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Definition
Capillaries
1 single celled endothelial used for exchage/fluid flux |
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Term
T/F: All capillaries are open at the same time. |
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Definition
False; they have a precapillary sphincter that controls whether the capillary is open or not. They are not all open at one point in time. |
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Term
What 2 things control the fluid flux in capillaries? |
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Definition
Hydrostatic pressure
Oncotic pressure |
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Term
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Definition
1. Flux occurs down a hydrostatic pressure gradient
2. Flux occurs into the area with High oncotic P
3. Flux depends on permeability
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Term
Net flux is proportional to ________________. |
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Definition
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Term
How do we calculate the net filtration pressure? |
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Definition
NFP = (Pc-Pif) - (∏p-∏if)
Pc = pressure in capillary
Pif = pressure in intersitial fluid
where P is the change in hydrostatic pressure
And ∏ is the change in oncotic pressure
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Term
What happens at the arterial end of the capillary? |
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Definition
The NFP is + so there is a net outward flux. A small amount of fluie leaves along with some soluble substances that cross the capillary. |
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Term
What happens at the venous end of the capillary? |
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Definition
The NFP is - so it tends to have a net inward flux back into the capillary. The returned fluid brings with it some soluble products of metabolism like CO2. |
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Term
The net flux overall in the body tends to be _______________. |
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Definition
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Term
Which system picks up the excess fluids and proteins and returns them to the blood. |
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Definition
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Term
When does the lymphatic flow increase? |
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Definition
When there is an increase in interstitial fluid pressure.
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Term
How does the interstitial fluid pressure increase to increase the Lymphatic flow? |
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Definition
If more fluid flows out of the capillaries
and if there is an elevated capillary pressure |
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Term
How does the lymphatic vessels act as a pump? |
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Definition
They contract surrounding muscles (this increases the pressure)
Pulsate adjacent arteries
And compress the tissues
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Term
The ____________ determines flux of fluids thus the solutes in the fluid which all affects the capillary ________. |
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Definition
Filtration coefficient (Fc)
permeability |
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Term
T/F: Capillary permeability varies with the type of solute and with the type of capillary and the size of pores, etc. |
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Definition
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Term
Capillary permeability is greatest in the _______ and the least in the ______. |
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Definition
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Term
How can we change the flux in our bodies? |
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Definition
You can constrict arterioles which lowers Pc
This makes more fluid enter the capillaries from the Interstitium.
If you lower the # of protein then you decrease your ∏p which makes more fluid leave the capillaries and create Edema. |
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Term
The heart pumps blood by first contracting the ___________followed by the ________. This causes changes in ____________. |
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Definition
Atria
ventricles
pressure (will increase if the chamber size decreases) |
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Term
Right atrium receives blood returning to the heart from the |
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Definition
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Term
Left atrium receives oxygenated blood from the |
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Definition
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Term
Right ventricle pumps blood to |
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Definition
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Term
Left ventricle pumps blood to |
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Definition
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Term
______ open and close to allow blood to flow in or out of chambers. |
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Definition
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Term
Atrioventricular valves control the flow |
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Definition
of blood from Atrial to the ventricles |
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Term
Pulmonic valves control the flow of blood from |
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Definition
the right side of the heart to the lungs |
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Term
Aortic valves control the flow of blood from the |
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Definition
left side of the heart to the systemic circulation |
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Term
The ventricles have thicker walls than the atriums because |
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Definition
they have to pump blood out of the heart.
They do additional work |
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Term
The bicuspid valve is aka ____________ and is located on the ___________ of the heart. |
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Definition
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Term
The tricuspid valve is aka ______________ and is located on the ____________ side of the heart. |
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Definition
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Term
The cardiac cycle is divided into 2 parts. What are they? |
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Definition
|
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Term
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Definition
ventricles are contracting |
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Term
During diastole the ventricles are |
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Definition
relaxed and filling up with blood |
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Term
What causes the first heart sound? |
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Definition
The closure of the mitral valves |
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Term
T/F: Ventricular systole is divided into isovolumetric contraction period and isovolumetric relaxation period. |
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Definition
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Term
What happens during isovolumetric contraction period of ventricular systole? |
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Definition
1. The mitral valve closes (makes first heart sound)
sn. the other valves are also closed for a short period of time
2. Ventricular pressure rises abruptly because all the valves are closed
3. Ventricles continue to contract until the left ventricular pressure is slightly higher than aortic pressure and right ventricular pressure is higher than pulmonary artery pressure.
4. Mitral valve open and signals the ejection period. |
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Term
What happens at the end of systole in the ventricles? |
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Definition
1. The ventricles relax
2. This causes a steep fall in intraventricular pressure
3. The blood from the large arteries wants to flow back towards the ventricles but this causes the Aortic and Pulmonic valves to snap shut.
4. Aortic closure of valves causes the 2nd heart sound
5. The ventricular volume remains the same but the pressure drops as the valves stay closed. |
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Term
What happens during ventricular diastole? |
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Definition
1. Ventricular filling occurs
2. When ventricular presure is less than atrial pressure, the AV vlaves open
2. Blood flows from the atria into ventricles
3. Most blood is fileld during the first thrid of diastole which is aka rapid filling period.
4. Middle third of diastole the inflow is at a standstill.
5. the last third of diastole is marked bny atrial contraction which gives an additional thrust to ventricular filling. |
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Term
When do you hear a 3rd heart sound? |
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Definition
During the rapid filling period of diastole as blood flows into a distended or noncompliant ventricle during atrial contraction. |
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Term
A fourth heart sound occurs during |
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Definition
the last third diastole as the atria contract. |
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Term
During diastole the ventricles increase their volume to 120mL this is called the ___________ and at the end of systole it is ___________. |
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Definition
End diastolic Volume
50 mL (end systolic volume) |
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Term
How do you calculate the stroke volume? |
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Definition
Stroke volume = EDV - ESV
End diasolic volume - the end systolic volume
120-50 = 70 ml
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Term
What is the ejection fraction and how do you calculate it? |
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Definition
ejection fraction is the fraction of diastolic volume that is ejected from the heart during systole.
Ejection fraction = SV/EDV
Stroke volume/ End diastolic volume
it determines the pump efficiency |
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Term
Stenosis occurs when there is |
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Definition
incomplete opening of valves |
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Term
An insufficeincy occurs when |
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Definition
there is an incomplete closure of valves |
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Term
Stenosis occurs when the valve is not completely open this _______ the flow through the valve. |
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Definition
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Term
Insufficiency of a valve is when it doesnt completely close this causes _____________ |
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Definition
backflow or regurgitation |
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Term
A mitral insufficiency can lead to either _____________ or ___________. |
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Definition
Mitral valve prolapse
Mitral Valve Regurgitation |
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Term
T/F: Mitral Valve Prolapse (MVP) is seen more in men. |
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Definition
False; it is more common in women |
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Term
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Definition
enlarged leaflets or too long of chordae tendinae |
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Term
What are some symptoms of MVP? |
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Definition
1. It can be Asymptomatic-- meaning no symptoms. Dont know they have it until they get a check up.
2. Could have midsystolic clicks
3. Could have late systolic murmurs
4. Can have chest pains (arrhythmias) |
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Term
List some complications of MVP |
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Definition
Can lead to regurgitation by rupture of the chordae.
Lead to infective endocarditis
Can form an emboli
lead to atrial/ventricular arrhythmias |
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Term
What are some causes for Mitral Valve regurgitation? |
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Definition
1. rupture of chordae tendina
2. Rheumatic heart disease
3.Hypertrophic myopathy
4. Left ventricle enlargement
5. Infective endocarditis
6. Abnormality in valves/papillary muscles
7. Ischemic heart disease (CAD)
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Term
What changes occur during Mitral Regurgitation? |
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Definition
As the disorder progresses the aortic stroke volume decreases because the left ventricular fucntion is impaired. The left atrial pressure thus increases. THe increase in atrial pressure is more pronounced if acute and severe. |
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Term
What type of murmur occurs during Mitral Regurgitation? |
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Definition
Systolic murmur occurs throughout systole. |
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Term
What are some complications of Mitral Regurgitation. |
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Definition
The volume overload of the left ventricle and atrium can lead to:
1. atrial arrhymthmias
2. pulmonary edema
3. left side heart failure
4. enlargement of LV which leads to S3 |
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Term
What causes Mitral Stenosis? |
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Definition
1. Thickening and calcification of the valves
2. Shortening/thickening of the chordae tendinae caused by Rheumatic fever and Strep |
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Term
T/F: During Mitral Stenosis the left atrium becomes dilated and thus increases the pressure. This increased in left atrial pressure is tranmitted to the pulmonary venous system and causes pulmonary congestion. |
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Definition
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Term
During mitral valve stenosis there is an impaired filling of the ________ which causes an incraese in pressure in the ________. |
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Definition
left ventricle
left atrium |
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Term
The murmur of mitral stenosis is heard during ______________ . |
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Definition
diastole
(sn: a opening snap may preced the murmur as a result of the incrase in LA pressure) |
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Term
What are some complications of Mitral Stenosis? |
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Definition
there is a pressure overload int he atrium that can lead to
1. LA enlargement
2. Atrial arrhythmias
3. Right heart failure due to pulmonary edema
4. thrombus formation |
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Term
T/F: Aortic Vavle Stenosis is chracterized by an increased resistance to ejection of blood from the LV to the Aorta. |
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Definition
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Term
In Aortic Stenosis there is a __________ amount of blood ejected intot he systemic ciruclation because the there is ___________ resistance. |
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Definition
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Term
Common causes for Aortic Stenosis is? |
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Definition
Rheumatic fever
Congenetial valve malformations
Senile calcification |
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Term
With Aortic Stenosis there is a _______________ that caues a ____________. |
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Definition
Late Systolic ejection murmur
4th sound |
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Term
Aortic Stenosis causes a decrease in ____________ and an increase in ________________ because of the reduced outflow. |
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Definition
aortic pressure
left ventricle pressure |
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Term
What are some complications for Aortic Stenosis? |
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Definition
It is a pressure overload in the ventricles that can lead to:
1. chest pain
2. angina, syncope (Fainting)
3. Left side heart failure
4. dizzy when exercise
5. Dyspnea
6. Cyanosis |
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Term
T/F: Aortic regurgitation is the result of an incompetent aortic vlave that allows blood to flow back to the LV during diastole. |
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Definition
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Term
What are some causes for Aortic Regurgitation? |
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Definition
Floppy valve leaflets or deformed aortic roots that are caused by:
1. Rheumatic disease
2. congential valve defect
3. aortic root dilation
4. hypertension
5. endocarditis |
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Term
Aortic Regurgitation produces a murmur during |
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Definition
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Term
During Aortic Regurgitation there is an increase in volume in the ________. |
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Definition
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Term
Aortic Regurgitation is due to a __________ overload of the LV and LA. |
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Definition
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Term
Some complications of Aortic Regurgitation include |
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Definition
1. LV dilation ventricular arrhythmias
2. fatigue, exercise intolerance
3. Angina
4. Pulmonary edema
5. Dyspnea |
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Term
What is known as the pacemaker of the heart? |
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Definition
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Term
The SA ndoe has the fastes intrinsic rate of firing around ________. |
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Definition
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Term
What are the electric pathways in the heart? |
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Definition
1. SA node
2. Internodal = from SA to AV
3. Bachmann bundle = SA to LA
4. AV node = 2nd pacemaker
5. Bundle of His
6. Purkinje fibers = impulse to ventricles |
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Term
How are cells in the heart electrically coupled? |
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Definition
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Term
What are the 5 phases of the cardiac action potential? |
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Definition
Phase 0 = rapid D.P
Phase 1 = Early R.P.
Phase 2 = Plateau
Phase 3 = final Rapid R.P.
Phase 4 = Diastolic D.P. |
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Term
What happens in each phase in the ventricular muscle? |
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Definition
Phase 0 = Na+ gates open and causes a D.P
Phase 1 = Na+ channels become inactive due to efflux of K or influx of Cl.
Phase 2 = Plateau occurs cuz K+ permeability is low so cell stays D.P. And Ca influx into cell via L-type Ca channels.
Phase 3= Final rapid R.P. Channels close and Ca and Na influx stop. K moves out
phase 4 = membrane resting potential |
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Term
What is special about the SA cardiac action potential? |
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Definition
It has a spontaneous phase 4 depolarization
aka
automaticity |
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Term
T/F: The SA node has a leak that continues until the threshold is firing reached. |
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Definition
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Term
When is the absolute refractory period reached? |
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Definition
When no stimuli can generate another A.P. During phases 0, 1, 2 and part of 3 |
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