Block I: ischemic disease Flashcards
[] is a major cause of vascular disability and death in the US
CAD
[] can cause overall diminished coronary artery perfusion relative to myocardial oxygen demand
CAD, can cause ischemic heart disease
[] is a fibro-fatty plaque which is the basic lesion of CAD
artheroma
describe an atheroma
a fibro-fatty plaque, that is the basic lesion of CAD
[] is a raided, focal plaque within the tunica interna of the coronary artery
artheroma
describe the composition of an artheroma
core of lipid (mainly cholesterol and cholesterol esters) with a fibrous cap
what are the four key risk factors of CAD
- hyperlipidemia
- HTN
- cigarette smoking
- DM
what are the HDL:LDL ratios that correlate to a person’s risk for CAD
LDL:HDL < 3 low risk
LDL:HDL > 5 high risk
LDL:HDL < 3 is [] risk for CAD
low
LDL:HDL > 5 is [] risk for CAD
high
diabetics usually have high [] which can be a contributing factor to CAD
triglycerides
what three syndrome related to ACS
- unstable angina
- NSTEMI
- STEMI
what is the pathophysiology of ACS
- endothelial damage (smoking, dyslipidemia, HTN, insulinemia)
- black formation
- rupture of unstable plaque
- platelet activation and plugging
- coronary thrombosis
- complete or partial vessel occlusion
there is a [] correlation between clinical symptoms and extent of ACS
modest
[] is caused by a fixed obsructive CAD i.e. stable plaque
stable/typical angina
a stable angina usuallly requires []% stenosis to be symptomatic
50
patient presents with
- substernal pain/discomfort
- provoked by exertion/emotional distress
- subsides with rest
- some SOA
what is your suspicion?
stable angina
what are some anginal equivalents?
- nausea
- lightheaddedness
- generalized weakness
- acute changes in mental status
- diaphoresis
[] is caused by ischemic events due to vaoconstriction or vasospasm. i.e. cold exposure, drug use (cocaine) or can be spontaneous
variant angina
how can cocaine cause ischemic coronary events?
- causes coronary artery vasospasm and vasoconstriction by increasing myocardial energy requirements
- also increases platelet aggregation
- chronic use significantly accelerates progression of artherosclerotic disease
- higher risk acute MI
[] clinical syndrome in which episodic chest discomfort occurs at rest without a usual precipitating factor
prinzmetal’s angina
what EKG changes are assoc. with prinzmetal’s angina
ST segment elevation changes, returns to normal once angina subsides
when does prinzmetal’s angina usually occur?
early in the morning, waking patients from sleep.
how is printzmetal’s angina treated?
responds well the nitrates or CCBs
-which can be used prophylactically
what is known as a pre-infarction angina
unstable angina
[] changing pattern of previously stable angina, or new onset or more severe angina
unstable angina
patient comes in with
- crescendo pattern of pain
- occured while resting
- has lasted 40 minutes, and has not been helped by the NTG that was given her in the ambulance
unstable angina
[] is characterized as a severe, fixed, obstructive disease with 90% stenosis
unstable angina
unstable angina usually consists of []% stenosis
90
patients EKG shows
- ST segment depression
- T wave inversion
what is your suspicion?
unstable angina
how can you tell a pre-infarction angina from an MI in lab?
usually troponins, which are released upon myocardial cell death. indicative of necrosis
*not end all be all
[] is ischemia of anterior myocardial wall segments, from a result of occlusion of LAD
anterior wall MI
ST elevations in leads V1, V2, V3, V4 are indicative
anterior wall MI
ST elevations must be present in at least [] conescutive leads to dx STEMI
2
what coronary artery is most likely to be affected by an anterior wall mi?
LAD
motion pattern of ischemic myocardial segments revels [] motion compared to other normally contractile segments
hypo or akinetic motion
specifically anterior
ischemia of inferior myocardial wall generally causes by occlusion of posterior descending artery OR distal part of left circumflex is called []
inferior wall MI
what arteries are usually assoc. with inferior wall MI
- posterior descending artery
2. distal part of left circumflex
changes in EKG leads II, III, aVF are usually indicative of []
inferior wall MI
what is important to note about inferior wall MIs
they usually present with hypotension therefore DO NOT GIVE NTG
why do inferior wall MIs cause hypotension?
they induce parasympathetic stimulation -> bradycardia, hypotension
ischemia of lateral wall generally causes by occlusion of LAD or L circumflex is []
lateral wall MI
what coronary arteries are involved in lateral wall MI
LAD or L circumflex
what EKG leads reveal changes in lateral MI?
I, aVL, V5, V6
ischemia of septal wall caused by occludion of LAD is [] MI
septal MI
what arteries are involved in a septal MI
LAD
what leads are involved in a septal MI
1, 2
what leads are involved in a posterior wall MI
1, 2, 6
what arteries are involved in a posterior wall MI
- R coronary
2. Left circumflex
[] is a symptom of myocardial ischemia that occurs most commonly during activity and relieved by resting
angina pectoris
who may present with atypical symptoms of MI
- women
- elderly
- diabetics
what are some uncommon presentations of MI
- nausea
- epigastric pain
- tooth pain
- dull body or arm aches
ischemic pain is classically felt []
retrosternally
what is levine’s sign
clenched fist over the heart
if a patient has had a heart attack before, what should their symptoms look like?
a duplicate of whatever occured with their first one
radiation of pain to arms or neck is more likely to characterize []
myocardial ischemia
what are the most common signs for myocardial ischemia pain radiation
- L shoulder
- upper arm
- inner aspect arm to elbow
- forearm
- wrist
- 4th or 5th fingers
*sometime jaw or neck or intrascapular
a patient presents with retro- sternal pain, what may you conclude about their condition
ischemic in nature
anginal pain lasts [] minutes
3-15 and subsides complete with not residual pain
substernal pain for 10 minutes with complete revocery may indicate []
anginal pain
chest discomfort for a few seconds is UNlikely to be []
ischemic
anginal pain lasting over [] minutes suggests unsatable angina, MI, alt. dx
20
anginal pain lasting ocer 20 minutes may suggest []
- unatsble angina
- MI
- other dx
what common precipitating factors for anginal pain?
- meals
- cold
- emotional distress
- exercise
what are some alleviating factors of anginal pain
- rest
2. NTG
what are some symptoms that should INCREASE the likelyhood of MI
- nausea
- diaphoresis
- vomiting
- syncope
- SOA
what are the most telling signs of an MI patient
- pale
- anxious
- diaphoretic
*cannot fake this
in early anterior infarctions the [] nervous system takes over and leads to []
sympathetic
tachycardia, hypertension
in inferior infarctions the [] nervous system takes over and leads to []
parasympathetic
hypotension, bradycardia
what is important to monitor on pts. neck if your suspect MI
JVD
what murmumr is most common with inferior wall MI
acute mitral valve regurgitation
are murmurs always indicative of MI
no, but NEW ones should raise suspicions
[] is the most common cause of acute mitral valve regurgitation
inferior wall MI
a new systolic murmur may signify []
papillary muscle dysfunction or rupture
or
herald ventricular septal rupture
a PMI abnormality may point to
dyskinetic infarcted area
what are important things to look for in cardiac exam if you suspect a patient has MI
- murmurs
- heart sounds
- PMI
what rectal check should you perform if you suspect a patient has an MI?
occult blood on stool
esp. if youre going to give anticoag- want to ensure pt. isnt having a bleed
list some diagnostic tests you would perform if you suspect MI
- EKG
- Troponin
- CBC/CMP
- PT/PTT/INR
- BNP
- D-Dimer
- CTA
- exercise electrocardio
- echo
- coronary angiography
myocardial ischemia delays [] in heart which can lead to EKG changes
process of repolarization
what EKG segments are most commonly affected by MI
- ST T wave
ST elevation indicates
STEMI, highly pathological
what, pathophysiologically, is happening when an ST segment is elevated
depolarizes incompletely and remains electrically more positive than uninjured area surrounding it
present in leads facing affected areas
ST depression is indicative of
angina
a horizontal ST is indicative
angina
what does an inverted t wave represent
angina where full thickness of myocardium is involved
if it is new its concerning
what does troponin represent
it is released from dead myocardial cells, indicative of MI
[] diagnostic test is most useful, non invasive procedure for evaluating a patient with angina
exercise electrocardiograph
if troponin is normal, what should be your next diagnostic test?
exercise electrocardiograph
what is a 2D doppler with various roles such as
evaluating valvular heart disease, L ventricular dysfunction, pericardial problems
echo
[] definitive diasnostic procedure for CAD
coronary angiography
[] visualizes location and severity of stenosis
coronary angiography
narrowing of []% viewd on coronary angiography is cliniclaly sig.
50
most lesions that produce ischemia are []% stenotic
70
[] shows whether obstructions are amenable to percutaneous transluminal coronary angioplasty or bypass
coronary angiography
what is the DOC for anginal pain
NTG
what is the MOA of NTG
relaxes cardiovascular smooth muscle and alters venous vessels
increases subendocardial perfusion to ischemic and non ischemic areas
**decrease in pre load
what anti-anginal causes a decrease in pre load
NTG
do not admin NTG if BP is less than []
90 mmHG
*also dont admin if markedly bradycardic or tachycardic
if pain doesn’t subside with NTG what should be on your radar
evolving infarction may be present
req. imm. attention
what are common side effects of NTG
- nausea
- HA
- dizziness
- hypotension
MOA BB
prevent angina by reducing myocardial oxygen requirements during exertion and stress
reduce HR, contractility, BP
[] is the only anti-anginal therapy proven to prolong life in patients wiht CAD and post MI
BB
[] is given as a f/u to MI, NOT during acute MI
BB
given 12 hours after they are stable or discharged once home
[] should be rxed for all patients with angina indefinitley
ASA
role ASA in treatment
anti-platelet
keep plateletls from being activated and sticking together- keeps them from forming fibrous clot
what are some other antiplatelets
- ticlopidine
- ticagrelor
- clopidogrel
[] should be started with unstable angina
hepratin IV
low molecular weight, becoming standard of care
- safer, more convenient
- PTT not risk
what is an absolute indication for thrombolytic therapy
- ST seg elevation w hx unstable angina
