Coronary Heart Disease Flashcards
layers of an artery
tunica intima, tunica media, tunica adventitia
atherosclerosis
pathologic process that causes disease of the coronary, cerebral, and peripheral arteries
what causes focal thickening of the tunica intima?
foam cells
foam cells
Macrophages that have consumed lipid, seen in atherosclerosis pathogenesis
what type of inflammatory cell is present in a fatty streak?
T lymphocytes
what initiates the formation of a fatty streak?
vascular injury
what can develop if the plaque remains stable?
fibrous cap
fibrous cap
dense, collagen-based layer of connective tissue that covers the well defined lipid core of a plaque
function of a fibrous cap
- provides stability to the plaque
- walls off lesion and prevents blood from coming into contact with the lipid core
what will happen if blood comes in contact with the lipid core?
clotting will occur and will eventually lead to occlusion of the vessel and ischemia
function of microvessels
originate from the tunica adventitia of large arteries to provide oxygen and nutrients to the outer layers of the arterial wall
as the atherosclerotic plaques expand, ….
they acquire their own microvasculature
what can result from plaque rupture?
microvascular hemorrhage , leading to progression of atherosclerosis
fibrous plaque develops as ________ accumulates
connective tissue
what does the connective tissue of the fibrous plaque consist of?
lipid-containing smooth muscle cells and an extracellular lipid pool
coronary arteries remodel in response to _____
atheroma formation
positive remodeling
increased vessel size occurring early in CHD to compensate for plaque accumulation in an effort to reduce lumen loss
symptoms of positive remodeling
unstable angina
negative remodeling
results in vessel shrinkage
symptoms of negative remodeling
stable angina
intraplaque hemorrhage is a result of …
plaque neovascularization
Intraplaque hemorrhage is a critical event that leads to …
- accelerated plaque progression
- instability
- ischemic vascular events
what two factors contribute to the pathogenesis of atherosclerosis?
- lipids
- inflammation
initial step in the development of atherosclerosis
endothelial vasodilator dysfunction
why does endothelial vasodilator dysfunction occur?
loss of endothelial-derived nitric oxide
the endothelial vasodilator dysfunction process is precipitated by …
oxidized LDL
endothelial dysfunction is associated with…
- hyperlipidemia
- diabetes
- HTN
- cigarette smoking
ways to improve endothelial vasodilator dysfunction
- correct HLD
- Give ACEi for HTN
role of inflammation in atherosclerosis
- macrophages eat oxidized LDL
- this releases inflammatory substances, cytokines, and growth factors that lead to further plaque proliferation
chronic inflammation leads to …. plaques and acute inflammation leads to …. plaques
stable; unstable and ruptured
atherosclerosis is asymptomatic until ……% of the vessel become occluded
70-80
2 processes of plaque progress
- chronic: slow luminal narrowing
- acute: rapid luminal narrowing associated with plaque hemorrhage or luminal thrombosis
plaque erosion
occurs in the absence of rupture when endothelium is missing at the plaque site
t/f plaque rupture and erosion may be asymptomatic
true
effects of atherosclerosis
- coronaries –> MI and angina
- CNS —> stroke
- periphery—> limb ischemia and poor healing
- renal—> RAS
- GI—> mesenteric ischemia
1 cause of death in US
cardiovascular disease
risk equivalents for CHD
a group of diseases that a person could have that allows you to assume that the patient also has CHD so you can treat them as such
examples of risk equivalents for CHD
- symptomatic carotid artery disease
- PAD
- AAA
- DM
modifiable risk factors for CHD
- smoking
- HLD
- HTN
- DM
- obesity
- sedentary lifestyle
unmodifiable risk factors for CHD
- premature CHD in a 1st degree relative
- age
- male sex
what is considered premature age for CHD?
under 55 in men and 65 in women
what age is considered a risk factor for CHD?
men: 45
women: 55
1 preventable cause of death and illness in the US
smoking
after 1 year of quitting smoking, risk of CHD can decrease by ……%
50
smoking promotes atherosclerosis by…
- increasing platelet adhesiveness
- raises endothelial permeability
- SNS stimulation by nicotine
risk of atherosclerosis increases as …. increases and ….. decreases
LDL;HDL
hypertension causes ….. to the arterial wall
mechanical injury
endothelial injury resulting from persistent high BP leads to …
plaque formation
at least 65% of people with diabetes die from …
some sort of heart or blood vessel disease
atherosclerosis has higher incidence and severity in …..
men
why are women at lower risk, but their risk increases after menopause?
estrogen has protective qualities, and when you hit menopause, you have a decline in estrogen levels
when do fully developed atheromatous plaques usually appear?
40s and beyond
……. predispose individuals to high blood lipid levels
hereditary genetic derangements of lipoprotein metabolism
what race is higher risk for atherosclerosis and CHD?
african american
how to risk stratify for CHD?
ASCVD 10 risk
screening for AAA
men aged 65-75 who have ever smoked need screened once
Aspirin use recommendations
should not give to CVD patients over 60
BP screening recommendations
screen everyone 18 and older at every visit
screening for DM
screen in adults 35-70 who are overweight or obese
what are the first things ordered when a patient comes in with chest pain?
- EKG
- cardiac enzymes
indications for EKGs
- used to assess for heart conditions
- all adults with chest discomfort without an obvious non-cardiac cause
- routinely ordered in elderly, DM, and syncopal patients
in patient’s with symptoms, and EKG should be done within ____ minutes if the patient’s arrival to the facility
10
if the initial EKG is not diagnostic but the patient remains symptomatic …
get serial EKGs every 15-30 minutes for the first 2 hours
earliest present of an acute MI
hyperacute T waves
t/f hyper acute t waves in an MI are commonly seen in clinical practice
false. they only exist for 20-30 minutes after onset of infarction so they are not often in the facility at that point
ST depression and t wave inversion in 2 continuous leads makes you suspicious of a …
NSTEMI
ST elevation makes you suspicious of a …
STEMI
cardiac enzymes evaluate for …
myocardial damage
troponin
contractile protein that normally is not found in the serum and is only released when myocardial necrosis occurs
most sensitive and specific cardiac biomarker
troponin
timeline of troponin levels
- increase within 3-6 hours
- peak at 24-48 hours
- return to baseline over 5-14 days
when do you measure troponin levels ?
- at presentation
- at 90 minutes
- every 6-8 hours after symptom onset x3
- or until trending down
….have more weight than a single reading for cardiac enzymes
trends
normal troponin level
0
CK-MB timeline
- increase 4-6 hours after injury
- peak around 24 hours
- remain elevated for 36-48 hours
positive CK-MB
if CK-MB is >5% of total CK and 2x normal
false positives for CK-MB
- exercise
- trauma
- muscle disease
- DM
- PE
CK-MD is …. sensitive and specific than troponin
less
myoglobin has … sensitivity and …. specificity
high; poor
fastest released cardiac enzyme
myoglobin
myoglobin can be detected as early as ….. after an MI
2 hours
most sensitive early marker for MI
myoglobin
LDH for MI detection
not specific
possible lab findings of MI
- leukocytosis
- elevated CRP
- elevated ESR
why is there leukocytosis in an MI?
under stress so white count will elevate
patients without biochemical evidence of myocardial necrosis but with …… are at risk of a subsequent ischemic event
elevated CRP
most commonly used and recommended initial noninvasive procedure for evaluating ischemia
stress test
2 methods of a stress test
- exercise
- pharmacologic
exercise stress tests are the preferred form of stress for what type of patients?
patients who can attain an adequate level of exercise
how do you determine if a patient can attain an adequate level of exercise?
if a person can walk for 5 minutes on flat ground or up 1-2 flights of stairs without needing to stop
indications for exercise stress test
- confirm diagnosis of angina
- determine severity of angina
- assess prognosis
- evaluate response to therapy
limitations of exercise stress test
-more false positives
exercise stress tests are most useful in…
patients with low pretest likelihood and a normal EKG
goal HR of exercise stress test
85% max
max HR
220-age
the intensity of exercise is periodically increased, continuing until…
- patient reaches max HR
- changes in heart function are detected on the EKG
- patient is symptomatic
positive exercise stress test
ST depression of 1 box
indications for terminating exercise stress test
- sustained ventricular tachycardia
- ST elevation in leads without diagnostic Q waves
CI to exercise stress test
- MI within 2 days
- high risk unstable angina
- uncontrolled arrythmias
- severe symptoms
- PE
- pericarditis
- aortic dissection
- HF
- baseline abnormalities on the EKG
indications for stress test with imaging component
- when the resting EKG makes an exercise EKG difficult to interpret
- localize a region of ischemia
exercise stress test with nuclear imagine
provides relative perfusion data following injection of a radioactive material before a stress test and then after a stress test
SPECT
- provides slices of the heart for imaging
- enable imaging of wall motion and estimation of EF
stress echo
Utilizes a echocardiogram along with an exercise stress test to increase the sensitivity and specificity of the stress test
what are you looking for in a stress echo?
- regional wall motion abnormalities
- LV dilation
pharmacologic stress test
used when a patient is unable to exercise to a sufficient cardiac workload or has a CI
pharmacologic stress tests are always combined with….
an imaging modality
preferred pharmacologic stress test agent
vasodilators (adenosine, dipyridamole, regadenoson)
CI of using vasodilators for pharm stress test
bronchospasm
2nd line for pharm stress test
adrenergic stimulating agents
coronary angiogram/cardiac catheterization uses
- evaluate or confirm the presence of coronary artery disease, valvular disease, or aortic disease
- evaluate heart muscle function
- determine the need for further treatment
right heart Cath is useful in…
pulm HTN
left heart Cath is used to assess…
cardiac valves and LV function
prep for coronary angiogram
- NPO 4-6 hours
- IV NS for 24 hours to flush out contrast
- hold metformin for 48 hours
ventriculogram
x-ray image of the ventricles
indications for coronary angiogram
- life limiting stable angina
- high pretest likelihood
- emergent for STEMI
relative CI to coronary angiogram
- renal disease
- allergy to contrast
risks of coronary angiogram
- stroke
- coronary artery dissection
- hemorrhage
- AKI
- femoral pneudoaneurysm
CXR for IHD
- useful to identify pulm causes of chest pain
- see mediastinal widening with aortic dissection
chest CT with IV contrast can help exclude …
PE and aortic dissection
Transthoracic echo can be helpful in detecting…
- effusions
- wall motion abnormalities
- aortic dissections
HR for CT of coronary arteries
below 50
if the CT of coronary arteries is positive, what should follow up?
cardiac cath
first line therapy in patients with acute coronary syndrome
nitrates
MOA of nitrates
nitrate enters vascular smooth muscle and is converted to nitric oxide, leading to activation of cGMP and vasodilation
SE of nitrates
reflex tachycardia
long acting nitrites
isosorbide
purpose of long acting nitrites
used for long term prophylaxis of angina
method of nitrate administration
non-parenteral
* SL
* topical
* IV (if pain persists or recurs)
AE of nitrates
HA
tolerance of nitrates
prolonged treatment of nitrates may induce a loss of response and decrease angina threshold
CI of nitrates
combination of nitrates and PDE5 inhibitors due to cGMP accumulation and dramatic reductions in blood pressure
action of morphine for MI
- decreases sympathetic tone
- decreases vascular resistance
- decrease O2 demand
use morphine with caution in …
hypotension, hypovolemia, and respiratory depression
aspirin therapy for MI
give high dose aspirin (chewed) to all MI patients to reduce mortality
use aspirin with caution in …
- active PUD
- hypersensitivity
- bleeding disorders
after you treat the acute MI with high dose aspirin…
go back to 81mg for long term management
….. is used in support of Cath/stent or if unable to take ASA
p2y12 inhibitors
how long toes p2y12 therapy need to last?
- 3-12 months
- mostly 12
- 3 is it is an isolated event that we can determine the cause
elective CABG and p2y12 dose
- plavix and brilinta: postpone for 5 days after last dose
- efficient: postpone for 7 days after the last dose
Glycoprotein IIb/IIIa inhibitors inhibits platelet aggregation at ……
final common pathway
…..is used in combo with ASA
heparin
….. is more effective than unfractionated heparin in preventing recurrent ischemic events
LMWH
…..should be started 24-48 hours after an MI once a patient is stable
beta blockers
BB reduce …
- infarct size and complications
- rate of re-infarction
- rate of life threatening tachyarrythmias and thus reduce mortality
- cardiac remodeling
MOA of ranexa
late Na channel blocker, decreases intracellular calcium overload
indication of ranexa
stable angina
advantages of ranexa
- no effect on HR or BP
- safe to use with ED drugs
SE of ranexa
prolonged QT interval
you see an increase in ….. post MI
ACE
use of ACE/ARBs …. at the scar site and remote to the infarct
reduce fibrosis and remodeling
t/f ACE/ARBs can help preserve myocardium in the setting of an MI
true
other pharm that can help in IHD
- Statins start immediately following diagnosis of acute coronary syndrome
- warfarin: thrombus history
- aldosterone antagonists: for selected patients with LV dysfunction
t/f CCB are first line vasodilators for IHD
false. not shows to favorable affect outcome
fibrinolytic therapy is used for ….. only
STEMI
SE of fibrinolytic
bleeding
anticoagulation post fibrolytic infusion
aspirin and anticoagulation (LMWH) should be continues until revascularization or for the duration of the hospital stay
when should you use fibrolytic therapy?
If and only if, cardiac Cath can’t be done within a few hours of the ischemic event
goal is to initiate fibrinolytic therapy within ……
30 minutes of arrival in ED
the greatest benefit occurs if fibrinolytic treatment is initiated within the ….
first 3 hours after onset of presentation
all patients with STEMI treated with fibrinolytic should be started on prophylactic …..
PPIs
CI of thrombolytic therapy
- any prior intracranial hemorrhage
- any trauma within the last 3 months
benefit of PCI (stents) are seen in…
unstable disease
stents are more effective than ….. for opening occluded arteries
thrombolysis
following PCI, patients should receive…
DAPT (ASA + P2y12) for 3-12 months
balloon angioplasty
inflation of a balloon within the coronary artery to compress plaque against the walls of the artery and open the lumen
stent angioplasty
similar to balloon angioplasty but involves the use of a small expandable mesh-like tube of thin wire along with the balloon
bare metal stents
vascular stent without a coating
drug-eluting stents
stent that slowly releases a drug to block cell proliferation
preferred stent used in PCI
drug-eluting stent
DAPT with drug eluting stents
requires a longer period of DAPT to prevent stent thrombosis so they aren’t appropriate for all patients
atherectomy
specialized catheter for mechanical removal of plaque from the arterial walls
CABG
procedure in which arteries or veins harvested from elsewhere in the body and are grafted to the coronary arteries to bypass atherosclerotic narrowing and improve blood supply to the myocardium
CABG is preferred method for revascularation in patients with …
- left main trunk artery stenosis
- poor LV function
On pump vs off pump CABG
on pump: connected to machine that stops the heart and perfuses the body
off pump: heart is still beating
Enhanced External Counterpulsation
noninvasive procedure performed on individuals with angina or HF or cardiomyopathy inn order to diminish symptoms of ischemia, improve functional capacity, and quality of life
goal of Enhanced External Counterpulsation
reduce cardiac workload and improve blood flow to the heart
results of Enhanced External Counterpulsation
relieve angina and decrease the degree of ischemia in a cardiac stress test
workup of stable angina
- cardiac enzymes
- EKG
- CBC to rule out anemia
- screen for risk factors
- determine pretest liklihood
resting EKG in stable angina
typically normal
low to intermediate pretest probability of stable angina
noninvasive stress testing
if the stress test in normal…
treat symptoms
if the stress test is abnormal …
refer to cardio and for possible cardiac cath
high pretest probability of stable angina
refer for cardiac cath
management of stable angina
- manage sx (NTG, BB, CCB, ranexa, revascularization)
- prevent CV events (modify risk factors and anti platelet therapy)
prinzmetal angina involves spasm of the coronary arteries, which leads to …
decreased coronary blood flow
what may cause onset of prinzmetal angina ?
- spontaneous
- cold exposure
- emotional stress
- vasoconstriction medications
…._ can occur as a result of spasm in the absence of visible instructive CHD
MI
……may induce myocardial ischemia and infarction by causing coronary artery vasoconstriction or by increasing myocardial energy requirements
cocaine
presentation of prinzmetal angina
- chest pain w/o usual precipitating factors
- ST elevation
- early morning
- no CAD on cardiac cath
management of prinzmetal angina
- emergent coronary arteriography (cath)
- nitrates
- CCB
order of management of acute coronary syndrome
- ASA
- NTG
- O2 (if needed)
- morphine
management of unstable angina and NSTEMI
- admit to hospital
- cardiac monitoring
- O2 if needed
- NTG
Primary PCI should be performed w/in …. mins of MI presentation?
90
thrombolysis should be administered within ….. of hospital presentation and ….. after onset of symptoms
30 minutes; 6-12 hours
all patients with a suspected STEMI should recieve…
- high dose ASA regardless of whether fibrinolytics are being considered or if low dose ASA has already been given
- reperfusion therapy (PCI or fibrinolytic)
manifestations of ischemic complications
- angina
- reinfarction
manifestations of mechanical complications
- HF
- MV dysfunction
- cardiac rupture
manifestations of arrhythmic complications
atrial or ventricular arrhythmias
manifestations of arrhythmic complications
atrial or ventricular arrhythmias
manifestations of embolic complications
stroke
PE
manifestations of inflammatory complications
pericarditis
Dressler’s syndrome
pericarditis post MI or CABG
etiology of Dressler’s syndrome
caused by an immune system mediated inflammatory response following damage to heart tissue or the pericardium
how long does dressers syndrome occur post MI?
1-12 weeks
symptoms of Dressler’s syndrome
CP and fever
presentation of RV infarct
- hypotension
- preserved LV function
RV infarctions present in 1/3 of patients with …
inferior wall infarction
treatment of RV infarction
treat hypotension with IV NS and inotropic agents (Epi)
MC location for ventricular free wall rupture
anterior or lateral wall of LV
ventricular free wall rupture is associated with …
- elderly
- poor collateral circulation
- first MI
ventricular free wall rupture occurs commonly within …. post MI
24 hours
mortality rate is …. for free wall ruptures
extremely high
how may ventricular free wall rupture present?
- pericardial effusion
- pulseless electrical activity
post MI ventricular septal defect is associated with … MIs involving the …
transmural; septum
MV regurg is a rare complication of MI due to…
ruptured papillary muscle
presentation of MV regurg due to ruptured papillary muscle
sudden onset decompensation HF
LV aneurysm puts patient at a high risk for ….
rupture
changes involved in cardiac event recovery
- diet
- exercise
- addition of appropriate meds
- increased frq of follow up care visits
discharge instructions for cardiac event
- education on meds, diet, exercise, and smoking
- referral to cardiac rehab
follow up for cardiac event
- follow up with cardio and PCP
- low risk: 4-6 weeks
- high risk: 1-2 weeks
dietary changes post-MI
- limit the intake of saturated and trans fatty acids, free sugars, and salt
- increase intake of fruits, veggies, legumes, nuts, and whole grains
exercise post MI
- work up to 150 minutes of moderate intensity exercise per week or 75 minutes of high intensity exercise per week
- aerobic exercise
psych issues following an MI
- debility
- activity/recreation
- depression
- sexual activity
- work/driving
cardiac blues
strong emotional reaction at the time of or soon after an acute cardiac event
consequences of depression post-MI
- emotional distress
- increased risk of another MI
- poorer prognosis
sexual activity post-MI
- uncomplicated: wait 1 week
- complicated: 2-3 weeks
- must be asymptomatic
cardiac rehab
improves cardiac function and reduces mortality / development of complications
3 aspects of cardiac rehab
- exercise
- education to help reduce risk factors
- counseling to help patients deal with stress, anxiety, and depression
Most common, serious, chronic, life-threatening illness in the US
IHD
….% of the population has sustained an MI
3-4
MC risk factors for IHD
- genetics
- smoking
- sedentary lifestyle
- poor diet
pathogenesis of IHD
demand for blood by the coronary arteries is greater than the supply
oxygen supply is determined by the….
blood flow
blood flow is regulated by …
pressure vs resistance ratio
most critical factor in oxygen supply
the radius of the blood vessel
what can influence the radius of the blood vessel?
- atherosclerosis
- vascular tone
- endothelial cell dysfunction
4 different types of IHD
- prinzmetal angina
- stable angina
- unstable angina
- MI (STEMI or NSTEMI)
Prinzmetal angina
drop in blood flow through the coronary arteries caused by a vasospasm in the artery, not by atherosclerosis
stable angina
chest pain that occurs when a person is active or under severe stress
unstable angina
chest pain that occurs while a person is at rest and not exerting himself
what does unstable angina result from?
results from plaque rupture and thrombus formation, but is not occluding blood flow
NSTEMI vs STEMI
STEMI: ST elevation and q waves
NSTEMI: ST depression and inverted t waves
what does NSTEMI result from?
plaque rupture and thrombus formation that partially impedes blood flow through the coronary vessels
what does a STEMI result from?
plaque rupture and thrombus formation that completely impedes blood flow through the coronary vessels
characteristics of stable angina
-predictable
-lasts 1-15 minutes
-goes away with rest or NTG
characteristics of stable angina
- predictable
- lasts 1-15 minutes
- goes away with rest or NTG
characteristics of unstable angina
- unexpected
- goes not go away with rest for NTG
- warning sign of an MI and is an emergency
ischemia presents as soon as there is a…
decrease in blood supply to the myocardial tissue
cardiac cells can tolerate …. for a short time
mild-moderate anoxia
prognosis of ischemia, injury, and infarct on the myocardial cells
- ischemia: cells usually return to normal after blood supply is returned
- injury: damage is reversible and may return back to normal but it also may not
- infarct: cells sustain irreversible injury and die
MI
irreversible myocardial injury resulting in necrosis of a portion of the myocardium
Acute MI suggests the infarct is …. days old
3-5
most severe and complicated type of infarct
transmural: goes through the entire wall of the myocardium
area of involvement of a NSTEMI
small area in the subendocardial wall of the LV, ventricular septum, or papillary muscle
what part of the myocardium is typically damaged first?
subendocardial area
area of injury for a STEMI
extends through the whole thickness of the heart muscle
a STEMI is associated with with atherosclerotic plaques in a coronary artery that causes ……
complete occlusion
nickname for ST elevation
tombstoning
type 1 MI
Spontaneous MI related to ischemia due to a primary coronary event such as plaque erosion and/or rupture, fissuring, or dissection
Type 2 MI
MI secondary to ischemia due to either increased oxygen demand or decreased supply
examples of type 2 MI
- coronary artery spasm (primzmetal)
- coronary embolism
- anemia
- HTN
type 3 MI
sudden cardiac death
type 4 MI
Mi associated with coronary angioplasty or stents
type 5 MI
Associated with CABG
silent ischemia is MC in ..
elderly, women, diabetics
myocardial stunning
reversible myocardial dysfunction following re-perfusion of an ischemic insult
hibernating myocardium
result in prolonged reduction in blood flow from coronary artery disease and causes ventricular contractile dysfunction that will improve after blood flow improves
artery associated with inferior wall MI
right coronary artery
artery associated with anterior wall MI
LAD
artery associated with lateral wall MI
Left circumflex artery
artery associated with posterior wall MI
posterior descending branch of the right coronary
artery associated with septal wall MI
LAD
inferior wall MI is often accompanied by a ____ due to involvement of the sinus node
decreased HR
effects of an anterior wall MI
affects the main pump so it can lead to decreased HR and BP and eventually HR
typical presentation of an MI
- episodic chest discomfort
- heaviness
- pressure
location of pain for an MI
- substernal
- can radiate to the left arm/shoulder, neck, jaw, back/scapula
duration of MI chest pain
2-5 min
setting of MI chest pain
typically with exertion
aggravating factors for MI chest pain
- exercise
- meals
- stress
- cold exposure
- sex
- morning
alleviating factors for MI chest pain
NTG
Rest
….test may be less accurate in women
stress test
how is prinzmetal angina treated?
CCB and nitrates to vasodilate
MC population to get prinzmetal angina
middle aged women
important PE assessments for IHD
- vitals
- heart and lung sounds
- neuro
- psych
- abdominal
everyone with chest pain CC gets a ….. and …..
EKG
cardiac biomarkers
TMI risk score
used to risk stratify patients to help determine who should undergo aggressive evaluation/treatment
risk on TMI scale
low risk: 0-2
intermediate risk: 3-4
high risk: 5 or more
risk on HEART scale
low: 0-3
intermediate: 4-6
high: 7 or more
