Shared Flashcard Set

Details

Physiology cardiac 14-15
Physiology cardiac 14-15
81
Physiology
Undergraduate 2
10/31/2012

Additional Physiology Flashcards

 


 

Cards

Term
total peripheral resistance (TPR)
Definition
arterial pressure is balance between cardiac output and the resistance to blood flow offered by the aerioles
Term
Pulse pressure
Definition
a measure of the strength of the pressure wave, is defined as systolic pressure minus diastolic pressure
pulse pressure =systolic pressure -diastolic pressure
Term
mean arterial pressure (MAP)
Definition
ia a function of cardiac output and resistance in the arterioles peripheral resistance
MAP is porptional to CO (cardiac output) times resistance (R) of the arterioles
Term
Systolic pressure
Definition
desirable at rest is 120mmHg or less
Term
Diastolic pressure
Definition
desirable is 80 mmHg or less
Term
laminar flow
Definition
Laminar flow tends to occur at lower velocities usually smooth
Term
turbulent flow
Definition
Turbulent flow is a less orderly flow regime that is characterised by eddies or small packets of fluid particles which result in lateral mixing
Term
vasoconstriction
Definition
decrease in blood vessel diameter
Term
active hyperemia
Definition
the process in which an increase in blood flow accompanies an increase in metabolic activity
Term
reactive hyperemia
Definition
An increase in tissue blood flow following a period of low perfusion
Term
baroreceptors
Definition
located in the walls of the carotid arteries and aorta, where they can monitor the pressure of blood flowing to the brainand to the body
Term
capillary filtration
Definition
if the direction of the flow is out of the capillary fluid movement it is known as filtration.
Term
capillary absorption
Definition
exchange of bulk flow into the capillaries
Term
edema
Definition
the accumulation of fluid in the interstitial space Swelling of tissues due to increased ISF.
Term
high blood pressure
Definition
also known as hypertension. High pressure on the walls of the blood vesselsaand may cause weakening and rupture.
Term
atherosclerosis
Definition
hardening of the arteries in which fatty deposits form inside arterial blood vessels
Term
vasodilation
Definition
increase in blood vessell diameter
Term
pulmonary circuit
Definition
In humans, the right side of the heart pushes blood through the pulmonary circuit
so that it can be oxygenated in the lungs
Term
systemic circuit
Definition
The general circulation of the blood through the body, as opposed to the circulation of the blood from the heart to the lungs and back to the heart
Term
Heart sounts (Lub)
Definition
vibrations following the closure of the AV valves create the first heart sound "lub"
Term
Heart sounds (dub)
Definition
vibrations created by semilunar valve
Term
diastole
Definition
is the relaxion phase of the heart; thw ventricles are filling. 80% is passive filling because of the AV valve is open. 20% due to contraction
Term
systole
Definition
contraction phase of the heart
Term
stroke volume
Definition
the amount of blood pumped blood ejected by one ventricle during one contraction
Term
cardiac output
Definition
is the volume of blood pumped per ventricle per unit time. It is equal to the heart rate times stroke volume. the average cardiac output is 5L/min
CO=SV*HR
Term
contractility
Definition
of the heart is enhanced by catecholamines and cerain drugs
Term
ejection fraction
Definition
the percent of EDV ejected with one contraction (stoke volume/EDV), is one measure foe evaluating ventricle function.
Term
isovolumetric
Definition
at the end of ventricluar contraction when the ventricle relaxes it becomes a sealed chamber and their is no change in blood volume
Term
end systolic volume
Definition
the heart doesnot empty completely of blood each time the ventricle contracts
Term
End diastolic volume
Definition
maximum filling occurs at the end of the ventricle relaxation (diastole)
Term
cardiac cycle
Definition
ECG through a single contraction-relaxation cycle
Term
electrocardiogram
Definition
represents the summed electrical activity of all cells recorded from the surface of the body
Term
Lead (for an ECG)
Definition
pairs of electrodes used to record ECG
Term
Fibrillation
Definition
myocardial cells contract in a disorganized manner, a condition known as fibrillation occurs. Artial fibrillation is common condition, which can lead to stoke if not treated. Ventricle fibrillation in life threatening
Term
Flutter
Definition
Atrial flutter is a common tachycardia (fast heart beat) that results from a rapid
electrical circuit in the atrium
Term
arrhythmia
Definition
are electrical problems that arise during the generation or conduction of action potientals throgh the heart, and it can usually be seen on a ECG
Term
AV Node Block
Definition
is also known as complete heart block because the conduction of electrical signals from the atria to the ventricle through the AV node is disrupted
Term
formula for cadiac output
Definition
cardiac output=heart rate X stroke volume
Term
formula for stroke volume
Definition
volume of blood before contraction - volume of blood after contraction = stroke volume
Term
P WAVE
Definition
ATRIAL DEPOLARIZATION
Term
P-R SEGMENT
Definition
CONDUCTION THROUGH AV NODE AND AV BUNDLE
Term
QRS COMPLEX
Definition
VENTRICLE DEPOLARIZATION
Term
T WAVE
Definition
VENTRICLUAR REPOLARIZATION
Term
functions of the cardiovascular system
Definition
1. transportation
2. regulation of body temperature
3. protection from blood clotting
4. immunity via white blood cells
Term
Exchange between the plasma and intersticial fluid only occurs?
Definition
in the capillaries
Term
All tissues of the body are near the capillary bed. Blood flow through capillary bed
Definition
is individually regulated and they are in a parallel arrangements
Term
what is heart murmurs due to?
Definition
incompetent or stenotic valves
Term
why is it important that cardiac muscles cannot be tetanized?
Definition
This long refractory period in cardiac tissue means that there has to be a gap long enough for the tissue to relax before the next contaction occurs. As a result Tetanus of the heart is impossible. What can occur though it that the heart goes into Fibrillation
Term
What's the benefit of tetany in skeletal muscles?
Definition
for fast reaction, recovery and movement
Term
what causes the heart valves to open and close
Definition
By minute electrical singles produced by the heart itself to open and close the valves
Term
how are the semilunar valves different from the atrioventricular valves?
Definition
When the heart is relaxed, the AV valves are open and the SL valves are closed. When the heart contracts, the AV valves are closed and the SL valves are open
Term
in what ways does the actiona potential of the myocardial (contractile) cell differ from that of a skeletal muscle cell?
Definition
Term
Congestive heart failure
Definition
condition marked by weakness, edema, and shortness of breath that is caused by the inability of the heart to maintain adequate blood circulation in the peripheral tissues and the lungs.
Term
atherosclerosis
Definition
characterized by the deposition of plaques containing cholesterol and lipids on the innermost layer of the walls of large and medium-sized arteries
Term
myocardial infaraction
Definition
A Myocardial Infarction is the technical term for a Heart Attack.

The hindrance of blood passage through veins and arteries. Basically a Heart attack.
Term
ventricular septal defect
Definition
During ventricular contraction, or systole, some of the blood from the left ventricle leaks into the right ventricle, passes through the lungs and reenters the left ventricle via the pulmonary veins and left atrium. This has two net effects. First, the circuitous refluxing of blood causes volume overload on the left ventricle. Second, because the left ventricle normally has a much higher systolic pressure (~120 mm Hg) than the right ventricle (~20 mm Hg), the leakage of blood into the right ventricle therefore elevates right ventricular pressure and volume, causing pulmonary hypertension with its associated symptoms.
Term
wolff-parkinson white syndrome
Definition
An abnormal heart rhythm giving specific electrocardiogram changes and attacks of paroxysmal tachycardia. It is a congenital condition caused by an accessory bundle between the atria and ventricles. There is no evidence that athletic exertion makes sudden death from WPW syndrome more likely. However, those with very low resting pulse rates, such as distance runners, may be more vulnerable to ectopic beats
Term
marfan syndrome
Definition
The most important complications of Marfan are those affecting the heart and major blood vessels; some are potentially life-threatening
aorotic enlargement
mitral valve prolapse
ineffective endocardiatisi
Term
pacemaker
Definition
An electronic device that substitutes for the natural pacemaker of the heart. It may be surgically implanted or placed externally on the chest
Term
defibrillators
Definition
An electrical device used to counteract fibrillation of the heart muscle and restore normal heartbeat by applying a brief electric shock.
Term
stents
Definition
A slender thread, rod, or catheter inserted into a tubular structure, such as a blood vessel, to provide support during or after anastomosis
Term
what are the three bipolar limb leads of an ECG:
Definition
right arm
left arm
left leg
Term
how many ECG leads are typically used for an ECG?
Definition
12
Term
what questions shouls you ask yourself when evaluating a person's ECG?
Definition
1. what is the heart rate?
2. Is the rhythm regular
3. are all normal waves present in recognizable form?
Is there a QRS wave for each p wave
Term
between which 2 phases of the cardiac cycle do the atrioventricular valves open?
Definition
During the diastole phase, the atria and ventricles are relaxed. Blood flows into the right and left atria. The valves located between the atria and ventricles are open, allowing blood to flow through to the ventricles.
Term
How does stretching cardiac muscle lead to greater contractile force?
Definition
this is the starling law
+increasing the stretch on cardiac muscle results in a stronger contraction
+increase stretch occurs when the heart fills with more blood (increased EDV)
+force increases because the sarcomers are closer to optimal length which maximizes the number of cross-bridges that can form
Term
in what ways does the action potiental of a myocardial (contractile) cell differ from that of a skeletal muscle cell?
Definition
The LV myocardium is larger, becuase the cells are larger (more contractile proteins). This occursbecause the LV pump out to the systemic circuit, which is a higher pressure system vs. Pulmonary circuit. Branched; striated; connected via intercalated disc and gap junctions
Term
Describe first degree block
Definition
in the PR interval is longer than normal (o.12-0.2 seconds)
Term
Decribe 2nd degree block
Definition
in second degree, all P waves are not followed by QRS complexes
Term
Describe third degree
Definition
the rhythm of the atria and ventricle are seperate
Term
what is the the pathway by which the electrical messages pass through the heart?
Definition
1.SA Node depolarizes
2. electrical activity goes rapidly to AV node via internodial pathways
3. depolarization spreads more slowly across atria. conduction slow through AV node
4. Depolarization moves rapidly through venticular conducting system to apex of the heart. depolarization wave speards upward from apex
Term
what intiates electrical signals in the heart?
Definition
SA Node
Term
what is the importance of the AV node have a slow conduction velecity
Definition
Term
dESCRIBE THE LARGE ARTERIES?
Definition
Ex: Aorta are elastic and they expand as the heart ejects blood into them. Their recoil allows for continous blood flow when the heart is in diastole.
Term
Describe Arterioles?
Definition
are the dite of variable resistance and they regulate blood flow into the capillaries.
Term
Describe veins?
Definition
veins are called capacitance vessels because they can expand and hold blood. more numerous than arteries larger diameter, hold more than half the blood in circulation
Term
what is the significance of veins having valves?
Definition
the valves only allow blood to flow back to the heart.
Term
Why is blood pressure in the arteries and arterioles pulsatile while the pressure in the capillaries and vein is not?
Definition
the amplitude of the pressure wave decreases over distances because of friction, and the wave finally disappear at the cappilaries.
Term
what happens to blood pressure as it moves throughout the systemic circuit (from arteries to arterioles to cappillaries and then to veins)
Definition
the amplitude of the pressure wave decreases over distance because of friction. by the time the blood reaches the veins it has decreased and finally disappears in the capillaries.
Term
Describe the process by which you are able to obtain someone's blood pressure using an inflatable cuff and a stethoscope?
Definition
Use a blood pressure cuff place around the bicep and listen for the pressure at the antecubum, inflate the cuff and listen for the first sound, this is the systolic pressure during the heart contraction; and when the sound stops this is the diastolic number, this is when the heart is relaxing.
Term
what happens to mean arterial pressure if you increase rate?
Definition
Supporting users have an ad free experience!