week 4: Perfusion - Coronary Artery Disease Flashcards
perfusion is the flow of the blood through arteries and capillaries delivering nutrients
true
cardiac circulation : review
top of the heart
bottom of the heart
broader base
bottom of the heart- apex, points down to the left
cardiac circulation : review
superior/inferior vena cava
pulmonary arteries
pulmonary veins
superior/inferior vena cava - return unoxygenated blood to the heart
pulmonary arteries - carries venous blood to the lungs
pulmonary veins- return freshly oxygenated blood to the left side of the heart
atrioventricular (AV) valves : what undergoes it
Tricuspid valve - right AV
Mitral valve- left AV
open during diastole ( ventricles fill with blood )
semilunar valves:
what undergoes it
pulmonic valve
aortic valve
open during systole
seminar valves :
pulmonic valve
aortic valve
open during systole
and describe it
pulmonic valve- right side
aortic valve - left side
open during systole ( blood ejected from the heart )
hemodynamics : review
SATA within the systemic circulation:
arteries supply tissues of the body with nutrient and oxygen rich blood
veins return blood to pulmonary circulation
LA/LV to aorta to body and back to RA/RV
all is true
hemodynamics review : pulmonary circulation
define what undergoes this
ra/rv pulmonary artery to lungs pulmonary veins to LA/LV
re-oxygenated and returned to systemic circulation
___ carries oxygenated blood ( give description on this )
arteries
carries oxygenated blood ( this is very bright red high pressure system ) –> the system that brings oxygen to tissues
this is carrying the deoxygenated blood which makes it a darker colour of blood
veins
Mechanical Properties : consists of what ?
this consists of mechanical and electrical
this is the amount of blood ejected by the left ventricle during each contraction
stroke volume
what is the hearts main goal ?
the hearts main goal is pump blood to other tissues maintaining perfusion
how well the heart can perfuse other tissues is measured through what ?
cardiac output
CO= HR x SV
3- 6 L/min in adult is this true or false.
this is true
what does preload and afterload influence?
this influences stoke volume and cardiac output
The heart will adjust to the needs of the body by increasing what ? ( for example : FIT workout or high incline workout this will be tough and because the body tissues need more perfusion the what is going to meet this demand ) ?
cardiac output
An increase volume and increase stretch and increase in SV is what law ?
frank starling law
Is this statement true or false.
The stimulation of our sympathetic nervous system will increase out heart rate and the stimulation of our Parasympathetic system will slow it down.
true
what are the five factors affecting cardiac output
cardiac contractility
heart rate
preload ( stretch )
afterload ( squeeze )
blood volume
Mechanical Properties “
preload and afterload quickly explain what they mean
preload - volume of blood in the ventricles at the end of diastole ( end diastolic pressure )
afterload - resistance left ventricle must overcome to circulate blood
increased in :
hypertension
vasocontriction
increase in afterload means increase in cardiac workload
electrical properties : what should we regulate ?
we should regulate heart rate and rhythm
electrical properties :cardiac muscle cells have the following properties
excitability
conductivity
contractility
refractoriness
when there is a decrease perfusion an area of the heart and cardiac heart cells dysrhythmias ( this calls for cardiac output and life threatening ). is this true or false?
true
What is SA ?
normally sets the rhythm of the heart rate ( natural peacemaker of the heart )
true or false. Heart needs its own oxygen to supply in order to function. They get it from the coronary arteries
true
this is an artery that feeds the front side of the heart
LAD ( left anterior descending )
this is around the heart lateral and posterior circumflex artery , where there is a disease, it interrupts the blood flow and feeding , anything distal = interrupted
left main coronary artery
coronary circulation
coronary artery : explain the supplies that undergoes right coronary artery and what blockage in this area can cause…
supplies : R atrium, R ventricle & part of LV ( interior ) , SA node, AV node, Bundle of His
blockage in this area can cause : RV failure
bradycardia heart block
coronary circulation :
coronary artery : left anterior descending ( LAD )
what are the supplies and what blockage in this area can cause ?
supplies : anterior wall of LV
Heart valves
Blockage in this area can cause : LV failure, dysrhthimias. highest mortality rate
coronary circulation :
coronary artery : circumflex
what are the supplies and what blockage in this area can cause ?
Supplies :
L Atrium
Lateral & Posterior walls of LV
SA node (50%)
blockage can cuase : LV failure *Dysrhythmias
LAD has the worst outcomes, and impact the ventricle ( main powerhouse ) for the perfusion which leads into left sided heart failure , life threatening dysrhythmias
true
what are the two kinds of chlosterol?
low density lipoprotein (LDL)
high density lipoprotein (HDL)
select all that apply regarding chlosterol:
Water-insoluble fat, must be bound to lipoproteins in the plasma (HDL, LDL)
Used in plasma membranes and to build Vitamins and Hormones
truuu
what are lipids made up (3 different)
chlosterol, triglycerides, phospholipids
what does cholestrol lead to?
cholesterol - chylomicrons - vldl and hdl - vldl leads to ldl
what does triglycerides lead to?
triglycerides - fatty acids - saturated and unsaturated; unsaturated leads to monounsaturated - oleic acid and polyunsaturated - omega 3, omega 6, linoleum acid
what is an ldl?
- majority of cholesterol in blood and most strongly associated with CAD risk
- Causes of LDL thought to include diet high in lipids, saturated fatty acids, and cholesterol
what is an hdl?
- reduces risk of CAD by removing cholesterol from LDL and stabilizing plaques
what is the goal in terms of cholesterol ?
reduce LDL’s and higher HDL’s
true or false regarding Hdl’s: It will actually reduce the risk of heart disease by removing cholesterol from the peripheral tissues and returning them back to the liver where it is disposed of,
which helps in stabilizing plaques.
true
what is the consequences of low perfusion?
myocardial ischemia - result increase oxygen demand or decrease o2 supply
true or false: When a person has narrowed coronary arteries, it reduces
supply of oxygen to the heart muscle. This leads to myocardial ischemia.
true
what are the clinical manifestations of CAD?
Stable angina pectoris (typical angina)
Silent ischemia (symptomless ischemia)
Unstable angina
Acute myocardial infarction (heart attack)
Heart failure
what is the first sign of CAD?
1st sign - ischemia, causes pain, managed by meds and rest, ALWAYS a warning sign that blood flow to heart muscle is reduced
what are the clinical manifestations of CAD - angina?
Angina Pectoris (chest pain)
* Angina is referred cardiac pain that results from ischemia
* Not everyone with ischemia develops angina (ex: silent ischemia)
* Various pain patterns (see below)
* May be described as pressure, aching, heaviness or squeezing
* Atypical symptoms: indigestion, aching jaw, fatigue, shortness of breath, dizziness, generalized anxiety, weakness, flu-like symptoms (often experienced by Women, Older adults)
* Adults over 80 may experience disorientation or acute confusion
what is atypical symptoms of angina?
indigestion, aching jaw, fatigue, shortness of breath, dizziness, generalized anxiety, weakness, flu-like symptoms (often experienced by Women, Older adults)
true or false: * Adults over 80 may experience disorientation or acute confusion
true
what does chronic stable angina mean?
Brought on by moderate to prolonged exertion
Pattern is predictable
Frequency, duration and intensity constant over months Only slight limitation of activity
Associated with a STABLE plaque
managed with nitrates
what is vasospastic angina?
Used to be called Prinzmetal or
variant angina
* Rare
* Angina due to vasospasm
* Triggers include cocaine, meds (migraine, chemo), magnesium deficiency, allergic reaction
very scary in young children
what are some manifestations of ischemia in CAD?
every organ needs oxygen to function
1) Angina pectoris
“Chest squeeze”
2) Diastolic and Systolic Dysfunction
Failure of heart to relax and fill properly
Results in shortness of breath (dyspnea)
3) Electrical disturbances
ECG changes (ST depression)
what does the heart layers consist of from inner to outer?
epicardium, visceral pericardium, pericardial space and parietal pericardium
what are factors that determine collateral circulation?
genetic disposition
chronic ischemia
anyone who doesn’t have this circulation or if they have any type of heart attack will turn into a lethal situation because they do not have those bypasses
collateral circulation
These are bypasses that develop
collateral circulation
vasospasm ( quick narrowing happening in thier artery ) closes artery which results in no blood that follows ( cocaine could be an example or certain drugs )
collateral circulation has been disrupted.( arterial occlusion is rapid )
True or false. Chronic ischemia could extended the years of survival ?
true, they have years of reduced blood flow, that will have collateral develop, they have a better chance of survival because of this circulation
true or false. Genetics ( somehow who has a history of hypercholesterol anemia ) doesn’t allow collateral to develop making them die in their early 20s.
true
Coronary artery disease : what is it ?
reduction of blood flow to the heart muscle primary muscle.
true or false. Plaque build up also affect large arteries as well
true
Coronary after disease : name all the characteristics
most common form of heart disease
also called coronary heart disease, or ischemic heart disease
what is the primary cause of CAD?
atherosclerosis
Atherosclerosis: what is it ?
this is injury of the blood vessels that causes inflammation plaque in the arterial wall
what is the definition of atherosclerosis ?
formation of fatty, fibrous plaque within the intima layer of the artery
this progresses for years until the disease is detected, could appear in childhood non actual symptoms ( at this point significant of narrowing the artery begin to develop )
atherosclerosis
true or false. Atherosclerosis is usually asymptomatic ?
true
SATA : ATHEROSCLEOROSIS
> 75 % occlusion- signs of ischemia with exertion
90% occlusion - ischemia at rest
all
role of endothelium : what is the tunica intima
tunica intima is the inner most layer made of endothelium
endothelium have many funcitons such as what ?
serves a barrier from coming into contact in toxins allowing blood to flow without allowing to stick the vessel
role of endothelium : define all of them
lines the blood vessels
separate the blood stream from the artery wall, preventing substances from the blood from moving into the blood vessel wall
atherosclerosis beings with a small injury to the endothelium lining
atherosclerosis : The stages : how many stages are there ?`
4 stages
how does atherosclerosis occur ? in the first stage
begins damage with the endothelial layer, tear in the lining breaks the barrier allowing LDL from the bloodstream to enter the intima layer to initiates an inflammatory process,
monocytes then move to the area and transform to macrophages adjust the ldl until become full and die
Fatty streak stage 2 of atherosclerosis : what is occuring ?
after the first stage , foam cells create fatty streaks, which is the earliest lesions of atherosclerosis ( this is asymptomatic atp, around age of 15 -> lumpy and more turbulent flow
Fibrous plaque ( stage 3 of atherosclerosis )
more prominenet ( age 30)
fibrous plaque stage platelets and ldls are released
platelets derived growth factor which stimulates smooth muscle vibration and thickening of arterial wall
collagen and elastic is released creating collagen cap or fibrous cap over the lipid pool this change causes hardening and thickening of the artery and taking up space and impairing blood flow
true or false. Complicated lesion is the worst scenario amongst all the stages of atherosclerosis. Define why
true , this is the most scary as the fibrous grows, this can become damage,
and become unstable.
It can rupture fibrous plaque and once this is ruptured it exposes the artery in our wall , platelets will rush creating a thrombus and if this is not remove –> lead to cell death
What trigger the inflammatory process?
when it cause injury to he endothelium
such as HTN
tobacco use , hyperlipidemia, diabetes, homocysteinemia, viruses and toxins
triggers Inflammatory to the endothelial cell layer of the artery can be physical or chemical
yes true
describe why hypertension and tobacco use can be trigger the inflammatory process ?
HTN = cause physical damage of the turbulent flow
Tobacco use - nicotine causes the release of epi, catecholamines, this causes vasconstric. which causes the heart BP to be elevated –> endothelial injury this also increases LDL
explain why hyperlipidemia and diabetes can trigger inflammatory process
hyperlipidema - high levels of LDL, causes damage to the vessel wall ( chemical injury )
diabetes - causes arterial damage
explain why homocysteinemia and viruses and toxins can trigger inflammatory process
Homocysteinemia - this results from inherited metabolic defect , which leads to very high levels of homocysteine ( high levels is toxic to endothelium )
viruses and toxins- leads to damage ( injury to endothelium
CAD : What are the risk factors ?
what are non modifiable and modifiable
non modifiable - increasing age
male > female
family history
modifiable - elevated serum lipid levels
HTN
Tobacco use
physical inactivity
obesity
psychological risk factors
true or false. People who are born female until the age around is ‘protected from cardio disease’ explain why ?
true, because they have estrogen, and estrogen is cardio protective ( it has an anti-inflammatory blood vessels )
true or false. The older you are, the higher the risk ( which comes down to plaques ) build up over time as we age and it becomes higher )
true
hyperlipidemia and adipose tissue does causes insulin resistance ,one of the most crucial things is to manage blood sugars. true or false.
true
Physical inactivity is associated with what?
associated with high blood pressure and cholesterol
what is the other risk factors that can lead to cad
dm
elevated homocysteine levels
clinical manifestations of angina?
Angina Pectoris (chest pain)
- Angina is referred cardiac pain that results from ischemia
- Not everyone with ischemia develops angina (ex: silent ischemia)
- Various pain patterns (see below)
- May be described as pressure, aching, heaviness or squeezing
- Atypical symptoms: indigestion, aching jaw, fatigue, shortness of breath, dizziness, generalized anxiety, weakness, flu-like symptoms (often experienced by Women, Older adults)
- Adults over 80 may experience disorientation or acute confusion
what is acute coronary syndrome?
Prolonged myocardial ischemia and not immediately reversible
➢Associated with unstable plaque which ruptures (thrombus forms)
➢Typically coronary artery is >90% occluded
➢Patients with ACS need immediate hospitalization
what is this? Prolonged myocardial ischemia and not immediately reversible
➢Associated with unstable plaque which ruptures (thrombus forms)
acute coronary syndrome
true or false regarding acute coronary syndrome: If it becomes too unstable, it can rupture. When a fibrous plaque ruptures or breaks off, it exposes the arteries, inner wall and platelets will rush to the site creating a thrombus. If this thrombus is not removed, it will lead to occlusion and cell death
true
ACS: unstable angina (USA)
Chest pain that is new, occurs at rest, or is worsening, usually lasts 15-20 minutes (pattern change)
* Often not responsive to rest or medication (nitro spray)
* Most commonly related to rupture of stable atherosclerotic plaque and partial occlusion by thrombus (clot may dissolve or could progress to infarction)
what is this: unstable plague that fully includes an artery
STEMI
what is this describing: Most commonly related to rupture of stable atherosclerotic plaque and partial occlusion by thrombus (clot may dissolve or could progress to infarction)
person could be sleeping or resting
ACS - unstable angina
what is acute coronary syndrome: MI? what are the two kinds
Plaque rupture and thrombus formation
* Cardiac cells can tolerate ischemia for 20 minutes before cell death begins
Necrosis begins on the endocardial surface (inside) and progresses to the pericardial surface (outside)
STEMI - full thickness infarction of ventricle
* NSTEMI - partial thickness infarction ventricle
Prolonged ischemia leads to irreversible
dysfunction: what does this referred to ?
acute coronary syndrome: myocardial infarction
what is this referring to? 100% occlusion EMERGENCY!!
STEMI
what does this refer to: The sub endocardial surface will begin to die. Then it will progress out to the entire
thickness of the heart muscle. It takes about 6 h to progress across the entire
thickness of the ventricle wall.
acute coronary syndrome: myocardial infarction
what are the manifestations of myocardial infarction?
chest pain: Severe, immobilizing, radiating to left arm (or other patterns)
* Usually in morning, at rest, last longer then 20 minutes, dyspnea: * See resp assessment
Atypical symptoms: weakness, fatigue,
anxious, dizziness
Older patients: sudden onset confusion, more likely to have atypical symptoms
what are the manifestations of the skin, CVS, resp, GI, other in terms of myocardial infarction?
Chest Pain
* Severe, immobilizing, radiating to left arm (or other patterns)
* Usually in morning, at rest, last longer then 20 minutes
Dyspnea
* See resp assessment
Atypical symptoms: weakness, fatigue,
anxious, dizziness
Older patients: sudden onset confusion, more likely to have atypical symptoms
Skin:
* ashen, cool, and diaphoretic (SNS) CVS:
* Initially ↑HR and ↑ BP but with ↓ CO then ↓BP
* Dysrhythmias Respiratory:
* Dyspnea, ↑ RR, crackles, O2sats
* Nausea and vomiting (common in Inferior MI/Pain)
* Fever up to 389 could last for a week (inflammation caused by myocardial cell death)
serum cardiac enzymes : describe what this contributes
Release of cardiac-specific enzymes when muscles die and release their contents
- Detection of serum cardiac enzymes help with diagnosis
what is important when it comes to diagnosing an MRI because they tell us there is a cardiac damage ?
serum cardiac enzymes
true or false. Unstable angina patient will not have a change in troponin levels but may present with ST changes on ECG, troponin will be elevated and in both STEMI and NONSTEMI
true
what is troponin? what is this one specific for ?
troponin is a myocardial muscle protein that is release with injury to cardiac muscle , it peaks and remains elevated for a long time and
this one is specific rises 3 to 12 hours after onset of an MI and peaks at 24 to 48 hours and return to normal in 5 to 14 days
what cardiac enzymes do we usually look at ?
ck and troponin this is the most reliable
this is the third major cardiac enzyme and it’s released within a few hours but its not specific to the heart and baseline
myoglobin
_____ rises 3 to 12 hours after onset there’s a delay in peak time 24 hours and then return to normal within 2 to 3 days
creatine cardiac enzyme
Myocardial Infarction: The Healing
Process define how the body heals
inflammation is body’s response to cell death
Neutrophils and macrophages remove all necrotic tissue in 2-3 days
(wall is thin and unstable)
- Collateral circulation may limit area of injury
- Over 2-3 months, scar tissue has replaced necrotic tissue (cannot contract)
- Necrotic zone identified by EKG changes (Q wave)
- Healthy myocardium hypertrophies and dilates as compensation (remodeling) and this can lead to heart failure
select all that applies within the myocardial infraction: healing process
* Necrotic zone identified by EKG changes (Q wave)
* Healthy myocardium hypertrophies and dilates as compensation (remodeling) and this can lead to heart failure
all true
what is a framingham risk score
this calculates the risk for MI in the next 10 years
After endothelial injury this will start accumulating in the tunica intima, damaging often associated with lots of fats and diabetes type 2
LDL
if a person has narrowed coronary arteries, it reduces the heart supplies which lead to what ?
myocardial ischemia
explain what stable angina again
causes pain that is predictable and manageable with rest or medication, sometimes lifestyle modi can help but for some it will continue to plaque and lead to clot and lead to MI
what’s the cause of angina ?
caused by imbalance by coronary arteries to supply oxygen to the heart muscle and the heart muscle demand for oxyegn
silent ischemia usually occurs to what type of people ?
diabetic and people who had previous MI
what is the common presentation of pain in angina ?
central chest pain that radiates to the neck shoulder and the jaw pain going to the right arm and epigastric area
could also present as an intrascapular pain ( between the shoulder blades )
True or false. Chronic stable angina is reversible ?
true
this is brought by an increase of physical activity , increases myocardial oxygen demand. No chest pain at rest but with any type of physical activity this will occur it is predictable.
chronic stable angina
true or false. Chronic stable angina is managed with nitrates.
true
What stage would chronic stable angina be in ?
fibrous stage, because at rest they are getting enough oxygenated blood but the ischemia is brought on by increase oxyegn demand, and exercising reduces that supply
it is still stable and no clot at this point
why is vasospastic not connected to atherosclerosis or CAD
its not because its ultimately connected to interrupting the perfusion so it could lead to MI
this is when there is a rupture of an unstable plaque, the clot creates a quick severe reduction of blood flow, meaning there is no oxygen being supplied and if ischemia is prolonged this causes damage to myocardium tissue and lead to necrosis
myocardial infraction
this is undiagnosed or untreated angina
myocardial infraction
what is abnormal Q
St elevation
T wave inversion
- area of cell death
- area of injury but not necrotic
- oxygen deprived tissue
Diagnostic Tests for CAD: coronary angiography
name what angiogram ad angioplasty
angiogram
- cather inserted in radial or femoral artery threaded to heart and contrast injected directly into coronary arteries
- done under xray using contrast dye
- identify blockages and collateral circulation
angioplasty
- same as angiogram, can open obstructed arteries by inflating ballon +/ - stent
