MI

Question 1

Differential diagnosis of chest pain

Answer 1

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

Question 2

Stable angina

Answer 2

Predictable chest pain with exertion

Question 3

Unstable angina

Answer 3

Unpredictable chest pain with exertion and at rest, Lasting 20 minutes or longer
Risk of MI within three years

Question 4

NSTEMI

Answer 4

Elevated troponin without ST elevation +/- ST depression

Question 5

STEMI

Answer 5

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

Question 6

Location of MI: I, aVL, V5, V6

Answer 6

lateral wall - LAD or Cx

Question 7

Location of MI: II, III, aVF

Answer 7

inferior wall - PDA

Question 8

Location of MI: V2-V5

Answer 8

anterior wall - LAD

Question 9

Location of MI: V1-V3

Answer 9

septal - LAD

Question 10

Troponin I -
Rises in:
Peaks at:
Normalizes in:

Answer 10

rises in 2-3 hours
peaks at 12 hrs
normalizes in 1-2 weeks

check q6 hrs

Question 11

CK-MB

• rises in
• peaks at
• normalizes in

Answer 11

rises in 2-12 hrs
peaks at 10-24 hr
normalizes in 2-3 days

used to diagnose re-infarction

Question 12

Exercise stress

Answer 12

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

Question 13

Stress ECHO

Answer 13

wall motion abnormalities

-compare before and after imaging

Question 14

Pharmacologic stress test

Answer 14

use dobutamine and adenosine over exercise

- Ischemia: ST Elevation 1 mm or more OR depression of 2 mm or more for 5 min

Question 15

Nuclear stress test

Answer 15

thallium to evaluate uptake before and after stress to identify perfusion defects

Question 16

Treatment of MI

Answer 16

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

Question 17

Reperfusion for STEMI/NSTEMI/unstable angina

Answer 17

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

Question 18

Post MI complications

Answer 18

MC - arrhythmia - VT/Vfib - fatal
mural thrombus
ventricular wall rupture - 4-8 days after MI
Pericarditis - Dressler syndrome

Question 19

Long term management post MI

Answer 19

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