Ischemic Heart Disease II Flashcards
Tests which every with chest pain gets
EKG and Biomarkers (if we are in the ER)
Best initial test for a patient with chest pain
EKG
How fast should a chest pain patient receive an EKG
Within 10 minutes of presentation
Intervals for EKG monitoring
15-30 minute intervals
First EKG finding for ACS
Hyperacute T waves - diffuse may be hyperkalemia
NSTEMI and Unstable Angina EKG
ST Depression or T wave inversion in 2 contiguous leads
How to tell a USA and NSTEMI apart
USA - Normal Troponins
NSTEMI - Elevated troponins
Evolution of a STEMI - 4 stages with timeframes
ST elevation - Minutes to hours after
Pathologic Q wave with inverted T wave - 1-2 days after
ST flattening with pathologic Q wave - 7-10 days
Normalization with persistent Q wave - Months after
Second step in working up chest pain for ACS
Draw labs - Cardiac Enzymes
3 Cardiac Enzymes
Myoglobin
CK-MB
Troponin
Troponin
Extremely sensitive and specific to the heart - best test
Increase, Peak, and Return to Baseline of Troponins
Increase: 3-6 hours
Peak - 24-48 hours
Return to Baseline: 5-14 days
Serial monitoring of troponins
At presentation
90 minutes after presentation
6-8 hours x3 or until trending down
Other things that can elevate troponins - 6
CHF
ESRD
Aortic dissection
PE
Myocarditis
PCI or CABG
How to determine if troponins are related to STEMI
Look for a serious trend upwards
CK-MB
Less sensitive and specific than troponins, usually use with troponins
Increase, Peak, and Return to baseline of CK-MB
Increase - 4-8 hours
Peak - 24 hours
Return - 48-72 hours
Why might we want CK-MB levels
Assess for an MI in a patient that has had one in the past two weeks
False positives with CK-MB - Five
Exercise, Trauma, Muscle Disease, DM, PE
Positive CK-MB value criteria
CK-MB over 5% of total CK
Myoglobin
MOST sensitive early marker for a patient having a coronary event - poor specificity - more so than troponin
When would we use myoglobin to test for ACS
Only used when they present within the first two hours of onset
Most sensitive early marker of an MI
Myoglobin
LDH Rise peak and return to normal in an MI
Rise - 24-72 hours
Peak - 3-4 days
Return to normal - 14 days
Not specific
3 other possible lab findings in ACS
Leukocytosis
Elevated CRP
Elevated ESR
Preferred for of stress testing
Exercise stress test
Those for whom a stress test can be performed
Can walk for 5 minutes on flat ground or up 1-2 flights of stairs without needing to stop
Four Indications for a stress test
Confirm diagnosis of angina
Determine severity of limitation due to angina
Assess prognosis in patients with known CAD
Evaluate response to therapy
Purpose of an exercise only stress test
For patients with a low or intermediate pretest probability
Often with potential atypical symptoms
Goal HR for an exercise stress test
85% max HR
In an exercise stress test, intensity is increased until….
Patient reaches max HR
Changes are detected on EKG
Patient is symptomatic
Positive stress test
ST depression of 1mm
7 Absolute indications to STOP a stress test
SBP drop over 10mmHg w/ ischemic symptoms
Moderate to severe angina
Nervous system symptoms - near syncope
Cyanosis or Pallor from Poor perfusion
Subjects desire to stop
Sustained V tach
St elevation of 1.0mm+`
7 Relative indications to terminate a stress test
SBP drop over 10mmHg w/o ischemic symptoms
ST or QRS changes - 2mm of downsloping
Non-VT arrhythmias including PVC triplets
Fatigue or SOB
Development of BBB
Increasing chest pain
Hypertensive reponse
Absolute contraindications for performing a stress test - 8
Acute MI within 2 days
High risk unstable angina
Uncontrolled symptomatic arrhythmias
Severe symptomatic aortic stenosis
Uncontrolled symptomatic HF
Acute PE or pulm infarction
Acute aortic dissection
Myocarditis or pericarditis
4 things that make doing an exercise stress test difficult - EKG hard to interpret
RBBB
WPW syndrome
ST depression at rest
Electrical testing
Main indication for imaging with a stress test
When resting EKG makes stress EKG difficult to interpret (LBBB, WPW)
Confirmation of results if uncertain
Determine if tissue is ischemic or infarcted
Assess efficacy of revascularization
Preferred medication class and three medications for an Pharm stress test
Vasodilators:
Adenosine
Dipyridamole
Regadenoson
Three Contraindications for Pharm stress test
Bronchospasm
Sick sinus
SBP under 90
Second line pharm stress test agents
Adrenergic stimulating agents
Dobutamine +/- Atropine
For patients when vasodilators are CI
Coronary angiogram
CATH!!
Reserved for intermediate to high risk patients
Gold standard diagnostic
Prep for cardiac cath
NPO for 4-6 hours
IV fluids to flush dye
HOLD metformin for 48 hours
Ventriculogram
Inject dye into ventricle to estimate EF
Indications for coronary angiogram (5)
Life limiting stable angina
High pretest likelihood of CAD or STEMI
Aortic valve disease or undergoing ANY valve surgery
Survivors of sudden death
Uncertain cause chest pain
Femoral pseudoaneurism
Potential complication of a CATH
Typical workup for STABLE ANGINA
Normal EKG
CBC possibly Troponin
Stress test for low to intermediate HEART score
Refer to cath for High HEART score
Done OUTPATIENT
Typical workup for UNSTABLE angina
EKG - ST depression, T wave inversions, could be normal
Negative troponins, maybe CK-MB
Low HEART score - No further testing - look for other causes
Intermediate heart score - Consider stress test, CATH if positive
High HEART score - CATH
Typical workup for an NSTEMI
EKG - ST depression, T wave inversions, could be normal
Positive troponins, may get CK-MB
Any heart score - CATH
2 goals of stable angina treatment
Manage symptoms
Prevent CV events
Initial management for USA, NSTEMI, STEMI
Admit and put on telemetry
Strict Bedrest
Oxygen if under 95%
Nitrates - 0.4 x 3 - every 5 minutes - everyone
ASA 162-325mg chewed - everyone
When to use clopidegrel, etc. for ACS
If truly allergic to aspirin
When to use morphine
May be used in pain refractory to NTG and ASA
Beta blockers in ACS
Use within 24 hours unless they have HF, Bradycardia, or Heart block
ACEI for ACS
Within 24 hours for everyone
Statins in ACS
Start within 48 hours or increase intensity
Door to balloon goal - CATH/PCI
90 minutes
Door to needle - tPA
30 minutes
MOA of Nitroglycerin
Converted to nitric oxide and activates cGMP - dilating blood vessels
CI of nitroglycerin
Hypotension, bradycardia, tachycardia, RV infarction
When not to give nitro
Inferior right sided wall MI
Administration of nitro in ACS
3 sublingual tablets, then IV
Treat a headache so you can keep giving nitro
Don’t do high doses or frequent doses for tolerance
Drug contraindicated with nitroglycerin
PDE-5 inhibitor
Morphine effect in ACS
Pain relief
Reduces oxygen demand
Reduces blood pressure
Aspirin for IHD
160-325 mg immediately chewed for ACS
81mg for long term
P2Y12 inhibitors and IHD
Used for cath support if they can’t take ASA
3-12 months after ACS
Load Plavix before cath
P2Y12 inhibitors and CABG
Need to stop 5 (clopidogre/ticegrelorl) or 7 (prasugrel) days before surgery
Glycoprotein inhibitors
Can be added on to prevent platelet aggregation after ASA and P2Y12
Tirofiban
Eptifibatide
Abciximab