MI Flashcards
Differential diagnosis of chest pain
MSK: Worse with palpation and movement - tx NSAIDs
Pleuritic: worse with deep inspiration - PNA, pleurisy, PE
GERD: worse with eating - burning. tx with PPI, H2blocker
PE: sudden SOB with Tachycardia and altered mental status - tx a/c
Aortic dissection: “tearing” pain - hemodynamically unstable. Tx with b-blocker and sx (if stafford A), b-blocker if stafford B
Anxiety: Associate with anxiety, sob, light headed
Pericarditis: Improvement leaning forward, Friction rub - tx: NSAID/ASA +/- colchicine
PNA: Productive cough and fever - tx abx
PTX: Sudden SOB - obs if small, chest tube/needle decompression may be required
> Thin young man - Spontaneous PTX
> Trauma -Tension PTX
Stable angina
Predictable chest pain with exertion
Unstable angina
Unpredictable chest pain with exertion and at rest, Lasting 20 minutes or longer
Risk of MI within three years
NSTEMI
Elevated troponin without ST elevation +/- ST depression
STEMI
elevated troponin with ST elevation
Risk factors: Age, hypertension, elevated cholesterol, family history, male, tobacco use
Sxs: Pressure/heaviness with radiation, SOB, Palpitations, nausea, diaphoresis
ECG: tombstoning, new LBBB
Location of MI: I, aVL, V5, V6
lateral wall - LAD or Cx
Location of MI: II, III, aVF
inferior wall - PDA
Location of MI: V2-V5
anterior wall - LAD
Location of MI: V1-V3
septal - LAD
Troponin I -
Rises in:
Peaks at:
Normalizes in:
rises in 2-3 hours
peaks at 12 hrs
normalizes in 1-2 weeks
check q6 hrs
CK-MB
- rises in
- peaks at
- normalizes in
rises in 2-12 hrs
peaks at 10-24 hr
normalizes in 2-3 days
used to diagnose re-infarction
Exercise stress
achieve 85% max HR or if develop CP
- Ischemia: ST Elevation 1 mm or more OR depression of 2 mm or more for 5 min
Stress ECHO
wall motion abnormalities
-compare before and after imaging
Pharmacologic stress test
use dobutamine and adenosine over exercise
- Ischemia: ST Elevation 1 mm or more OR depression of 2 mm or more for 5 min
Nuclear stress test
thallium to evaluate uptake before and after stress to identify perfusion defects
Treatment of MI
Initial management: > ABCs > preliminary H&P > 12 lead ECG - STAT > cardiac monitor > O2 prn to keep SpO2 >90% > IV access and draw labs > ASA 324 mg > Nitrates - unless contraindicated - decreases preload and O2 demand ACTIVATE CATH LAB
1st 24 hrs:
> high intensity statin - atorvastatin 80 mg prior to cath lab
>B-blocker (metoprolol or atenolol) unless HF, bradycardic, hypotensive, advanced AV block, bronchospasm
>Antiplatelet therapy - clopidogrel, prasugrel, or ticagrelor, in addition to aspirin
> Parenteral anticoagulant therapy:
- if PCI: heparin gtt or bivalirudin
-if no PCI: enoxaparin or fondaparinux
> Keep K > 4, Mg >2 to reduce arrhythmia risk
Reperfusion for STEMI/NSTEMI/unstable angina
STEMI:
PCI within 90 min
fibrinolytic therapy if PCI delayed > 120 min
NSTEMI/unstable angina
> fibrinolytic therapy is not indicated
> unstable pts may require urgent PCI
> stable can wait 12-24 hours for angiography
Patient with severe CAD (3v or L main) may be candidates for CABG
Post MI complications
MC - arrhythmia - VT/Vfib - fatal
mural thrombus
ventricular wall rupture - 4-8 days after MI
Pericarditis - Dressler syndrome
Long term management post MI
Aspirin indefinitely
Clopidogrel - STEMI at least 12 months, NSTEMI at least 1 month
B-blocker indefinitely
ACE/ARB - if has HF or LVEF less than 40% to prevent remodeling - start early
Aldosterone antagonist - spironolactone or eplerenone - in patient has LVEF less than 40% or diabetes - mortality benefit - start early
statin
nitrate
exercise
smoking cessation
dietary modifications
