exsc 531 test 1
VO2=___ * _____
MAP= ____ * _____
CO * avo2 diff
CO * TPR
The right heart is devoted to ______ circulation and pumps _______ blood to the lungs.
Left heart is devoted to _______ circulation and pumps _____ blood to the body for continuation of aerobic metabolic function.
Name the pathway of blood through the heart
Right Atrium, Intra atrial septum, tricuspid (right A_V valve), right ventricle, pulmonary semilunar valve, left atria, bicuspid, left ventricle, aortic semilunar valve, interventricular septum.
Name the path of blood through the coronary artery system.
right coronary artery, right interventricular and the marginal branches, left main coronary artery, left anterior descending coronary arter, left circumflex coronary artery
what does the coronary sinus do?
vein that returns blood to heart through right atrium
What do the bicuspid and tricuspid valves prevent?
what happens if this fails?
regurgitation (back flow) of blood back into atrium.
Loss of ability to pump blood and loss of contracility
What are the three layers of the heart?
endocardial, myocardial, and epicardial
whats the function of the epicardial layer of the heart?
serves as a lubricative outer covering
whats the function of the myocardial layer of the heart?
filled with contractile proteins to pump blood
whats the function of the endocardial layer of the heart?
serves as a protective inner lining of the chambers and valves
What does each part of the ECG wave represent?
the P wave represents atrial repolarization
QRS- ventricular depolarization
T wave- rapid repolarizaiton of ventricles
How is the heart affected if there is an obstructed artery?
it stops receiving blood & that part of the heart will die (myocardial infarction)
What do specialized heart cells in the conduction system do?
move an action potential, regulate heart rate, BP, & CO
what are the 3 functions of the atrium?
top off ventricle
AV node's function
gather action potential and slow them down
Bundle of Kent
abnormal pathway that reduces function of AV node
Function of arteries and arterioles
conduct arterial blood to the systemic capillary beds
How can you tell the difference between an artery, arteriole, and capillary?
tissue layer is thick and protects arteriesq
smooth muscle with contractile proteins for vasoconstriction and vasodilation
endotherial layer provides smooth surface for blood to go past
importance- reduces resistance to blood flow so blood pressure is low and nothing clings to the smooth surface.
what is the Vaso Vasorum?
Arteries and Veins own blood supply
Name the blood pressure at various locations:
aorta and large arteries
small arteries and arterioles have less ___
elastin and more smooth muscle, making these vessels important resistance vessels
function of veins and venules
to conduct venous blood to the heart for delivery to the lungs for re-oxygenation
what are veins distensibility characteristics?
can accommodate additional volume without additional transmural (internal) pressure increase.
therefore pressure and volume have no relationship
What are the special properties of arteries and veins?
arteries have elastic recoil characteristics. (swell with systole and recoil with diastole)
veins- compliance characteristics (with sympatheric stimulation veins contract and are able to continue to augment venous return)
During exercise muscle blood flow ? (increases or decreases)
During exercise blood flow to the splanchnic, renal cerebral, and coronary tissues? (Increases or decreases)
During exercise blood flow to the skin? (in or dec)
Sa node serves as
pacemaker of the heart
Describe the Sa node role in conduction system
Spontaneous electrical activity in the SA node reaches the depolarization threshold and fires, spreading the depolarization over the atria resulting in atrial contraction.
What role does the AV node play on conduction system?
The Av node (at floor of right atrium) connects atrium and ventricle by left and right bundle branches.
Why is the delay in the depolarization of the av node important?
it allows atrial contraction to empty atrial blood into the ventricles prior to ventricular depolarization and contraction.
what is the path of the conduction system?
SA node-> AV node-> AV bundle->left and right bundle branches-> Purkinje fibers
how is central blood pressure regulated (long term)
briefly describe the Renin-angiotensin-aldosterone system
Kidneys regulate blood pressure by adjusting the volume of blood. Low BP causes the release of renin which converts angiotensinogen to angiotensin 2. Angiotensin 2 constricts blood vessels and stimulates the release of aldosterone by adrenal cortex. Aldosterone increases Na+ and water reabsorption by kidneys. Both of these increase blood volume and arterial pressure.
How is BP regulated short term?
Autonomic control in the Medulla through sympathetic and parasympathetic activity.
receptors stimulate a1 receptos everywhere EXCEPT heart for vasoconstriction to augment venous return.
or b2 for vasodilation
what do a2 receptors do?
inhibit release of NE; promote blood clotting
what do b1 receptors do?
increase heart rate and strength of contraction & stim renin release from kidneys
intrinsic homeometric response
reduction of what system causes heart rate to increase to 100
reduction of parasympathetic activity
Central BP regulation
what is the Frank Starling Law of the Heart
optimal or increased tension leads to increased contractility and stroke length.
increased initial fiber length increases tension
What factors affect stretching of the myocardium?
Atrial contribution to ventricular filling, total blood volume, body position, Intrathoracic pressure, intrapericardial pressure, venous tone, pumping action of skeletal muscle.
Central Homeometic Regulation is dependent on
HR and calcium
as hr increases, calcium is associated with the contractile proteins for a greater portion of the cardiac cycle.
greater calcium per minute, greater tension, greater contractile state of heart, greater SV
What is the process of sympathetic stimulation of calcium release?
calcium is stored in SR and released from terminal cisterns. It binds to C-receptor on troponin causing shape change. This causes active sit on actin to bind with myosin and form cross bridges.
What affect does the shortened time spent in systole have on calcium release?
During exercise you spend less time in systole and more time in each cardiac cycle as a result each minute there is more calcium and SV is increased.
4 short term peripheral BP regulation
a1 vasoconstriction (norepi)
b2 vaso dilation (norepi)
active sympathetic cholinergi vasodilation (in sweat glands & blood vessels in skeletal muscles)(ACH)
parasympathetic cholinergic vasodilation (cranial and sacral areas) (ACH)
what is the metabolic hypothesis?
local blood flow is governed by the metabolic activity of that tissue.
these factors override any extrinsic factors resulting in dilation and lower TPR in working tissue.
Name 5 vasodilation substances
tissue pressure hypothesis-
increased tissue perfusion produces an increase in blood volume of the tissue and net transfer of blood from intravascular to extravascular compartments. The increased pressure compresses the walls in capillaries and reduces blood flow into the tissue.
smooth muscle contracts in response to stretch and is followed by relaxation with an increase blood flow.
What is the main way of regulating Long Term BP?
altering blood volume via Renin-Angiotensinogen Aldosterone System and kidneys.
increase in blood volume causes a rise in blood pressure and water retention
decrease in blood volume reduces blood pressure.
High Blood pressure damages endothelial cells leading to ... (6)
What is the BP range for pre hypertension
SPB (120-139) DBP (80-90)
a persistent elevation of diastolic blood pressure, systolic blood pressure, or both measured on at least two separate occasions at least 2 weeks apart
what percent of cases are idiopathic hypertension (primary) and secondary?
1 in ___ adult Americans have hypertension
what are 3 causes of hypertension?
narrowing due to stenosis at the opening of the arterioles from the aorta increase BP in arteries (most common)
age related elasticity loss in artieries
what are the nonmodifiable risk factors of hypertension?
family history of CVD
Gender (male over 55, female over 55 or after menopause)
Ethnicity (Black Hispanic)
What are modifiable risk factors of hypertension?
Personality traits (hoplessness & hostility)
long-term alcohol abuse
hormonal status (menopause, hysterectomy)
Causes of Secondary Hypertension
Stenosis of aorta
Pheochromocytoma (rare catecholamine-secreting tumor)
effect of drugs
what does ACE inhibitors stand for?
Angiotensin Converting Enzyme Inhibitors
what factors regulate coronary blood flow
MAP or tissue pressure
Sympathetic adrenergic control by b2 receptors
what is pressure work?
large increases in MAP (afterload) with small increases in venous return (preload).
myocardial oxygen demand from pressure work is greater then that for volume work
small increases in MAP with large increases in venous return
raise MAP but is not associated with heart disease
when the heart is doing pressure work there is a _____ oxygen demand
Mild Atherosclerosis lesions cover _____% of lumen
Sever atherosclerosis lesions cover ____% of lumen
What are the NCEP ATP III Guidelines for desirable levels of blood lipids and lipoproteins
total cholesterol <200 mg.dL
LDL-C <100 mg dl
HDL-C > 40 mg dL
Triglyceride <150 mg.dL
Injury in the focal artery impairs (2) ___
permeability and loss of ability to produce nitric oxide
What happens without NO?
increase platelet aggregation, increase cell adhesion, increased smooth muscle cell migration and proliferation, loss of avenue for vasodilation
What are the Major steps of Pathogenesis of Atherosclerosis
injury, increased permeability, inflammation, proliferation, fatty streak, necrosis, repair, fibrous plaque, complicated lesion
Injury is caused by
high shear forces, turbulent blood flow, hypertension, nicotine, oxidized LDL, glycated substances (hyperglycemia)
injury leads to endothelial dysfunction and increased permeability which leads to
impaired vasodilation, increased vasospasm potential, increased permeability (lipids), increased platelet aggregation
whats the process of inflammation?
1.) platelets release PDGF
2.) PDGF enhances monocyte binding
3.)PDGF increases growth and migration of smooth muscle cells from the media to the intima which becomes an important part of plaque
How does PDGF enhance monocyte binding?
monocytes differentiate into macrophages
macrophages are phagocytic and oxidize LDL
Oxidized LDL can more easily enter the endothelium (where injury takes place)
How are Fatty Streaks formed?
Smooth muscle and macrophage accumulate oxidized LDL forming "Foam Cells"
foam cells release cholesterol into the cell and surround areas around the cell forming fatty streaks
_____ is the earliest detectable subclinical sign of atherosclerosis
plaque formation leads to
cell death or repair
Necrosis leads to
lumen diameter is reduced,
when diameter is reduced by 40% complete compensation is reached and impairment of blood flow occurs
Can you have inflammation before Artherosclerosis?
Yes High blood pressure can cause inflammation
What are 3 ways of a hospital reducing the affects of atherosclerosis?
How does a catherization work?
a wire with a balloon attatched opens pushing the plaque against the wall so it reopens the lumen for blood to flow
How do stents work?
its put on the end of a catheter like a balloon but it doesn't open the vessel as much as a balloon so a person would need to be put on blood thinners.
Whats a bypass?
rerouting veins or arteries
what are Emerging risk factors for heart disease
Major Signs or Symptoms of CVD and Pumlonary DIsease
Pain, discomfort in chest, neck, jaw, arms due to ischemia
Shortness of breath at rest or mild exertion
Palpitations or tachycardia
decreased blood supply and o2 to the tissue (through coronary arteries to heart) resulting in hypoxia- causing chest pain and claudication
What are the 4 steps to health screening?
1.) Medical/ Health history questionnaire
2.) CAD risk factor stratification
3.) informed consent
4.) Exercise Testing/ Exercise
Whats the order of testing?
Take resting measurements, cardio, muscular fitness, flexibility
whats a true-positive test?
true negative test?
true pos- patients has CAD and test is abnormal
true neg- patient does not had CAD and test is normal
false positive test?
false pos- patient doesnt have CAD but test is abnormal
false neg- patient does have CAD but test is normal
percentage of true pos tests in patients with cad. as the rate of false neg tests increases sensitivity decreases
how do you calculate sensitivity?
true pos/ (true pos + false neg) x 100
what causes false - negative tests?
failure to reach 85% of age predicted max hr
failure to recognize non ECG signs and symptoms
musculoskeletal limitations to eercise preceding cardiac abnormalities
what does SMART stand for in the statement, " Goals should be smart"
specific, measurable, attainable,realistic, timebound
the dose response curve represents?
HR and Vo2 changes as you begin an exercise perscription
___ had a sharp response when you start exercise
____ takes a long time to improve on dose response curve
whats overload principle?
stressing the body beyond the point the body's used to
frequency intensity time type
intensity is measured in
frequency & duration
Relative intensity includes ____ which absolute intensity does not.
What is the Karvonen Method for HR
target hr range= ((220-HR rest) x .5) + hr rest
high intensity is above ____ METS
How much exercise does the ACSM guideline reccommend per week?
5-7 days a week of 30 minutes or 150 minutes a week minimum
20-60 min of continuous or intermittent exercise a day
exercise duration is inversely related to exercise ____
what are the general resistance training guidelines?
- 1 to 2 sets
- 10 to 15 repetitions
- Light to moderate weight (RPE= 11-13)
- 8-10 exercises involving major muscle groups
- A minimum of 2 days per week
- A warm-up of the muscles being worked should be included
what are the modalities of training?
- Isometric- static training. Only strengthens you at that one position. Don’t go through a full range of motion.
- Dynamic constant external resistance- full range of motion
- Isokinetic- against resitance
- Plyometrics- box jumps.
whats the 2 for 2 rule?
If the client can complete two more rep then the rep goal in the final set of an exercise for two consecutive training sessions the load in all of the sets for that exercise during subsequent training sessions can be increased.