Cardiovascular Emergencies Flashcards
What diseases are part of acute coronary syndrome?
- Unstable angina
- NSTEMI
- STEMI
What is the classic description of cardiac chest pain?
Intermittent substernal chest pressure, usually on the L side which radiates to the arm and neck, exacerbated with exertion and associated with SOB, diaphoresis, nausea, and palpitations
The classic description of cardiac chest pain is more often the exception than the rule. What are some aspects of more common presentations?
Pain can occur anywhere from the umbilicus to the neck, and to the back
Can be sharp or burning
People with diabetes and the elderly may have no chest pain
Women may present with fatigue, SOB, and generalized weakness
Physical exam findings in patients with ACS?
Highly variable
-Normal appearance to full cardiac arrest
-Diaphoretic, hypotensive or hypertensive, tachycardic or bradycardic, or dyspneic
May have normal heart sounds or a murmur from a ruptured papillary muscle or valve
+/- signs of heart failure (S3, JVD, pedal edema, pulmonary edema)
The high variability in presentation makes ruling out an ACS by secondary survey alone very difficult. Classic findings may lead you to increase your pre-test probability, but unless your evaluation leads you to another high probability diagnosis, be wary of removing ACS from your differential.
Yes.
Diagnostic criteria of an acute MI?
2 of the following 3:
- Consistent clinical history
- EKG changes
- Changes in cardiac enzymes
EKGs are an essential screening tool in anyone with chest pain. it can be diagnostic of acute MI if ___ are present, as they are in nearly 40% of cases. Interpret non-specific findings in the context of ___. Nearly ___% of patients with ACS initially have normal or non-diagnostic EKG. ___ tend to be more useful, and the majority of patients will show signs of ischemia.
ST elevations; old EKGs; 50; Serial EKGs
What location MIs are not measured by the traditional 12-lead EKG? What should be done in this situation?
Posterior and R-sided
Look for reciprocal changes (ST depressions in leads on the opposite side of the heart), then order appropriate extra leads (V7, V8, V9 for posterior, V4R for R)
List the 6 general MI locations.
- Anterior MI
- Septal MI
- Inferior MI
- Lateral MI
- Posterior MI
- R Ventricular MI
Location of ST elevations and reciprocal depressions in anterior MI
Elevations: V1-V6
Depressions: none
Location of ST elevations and depressions in septal MI?
Elevations: V1-V3
Depressions: none
Location of ST elevations and depressions in inferior MI?
Elevations: II, III, aVF
Depressions: I, aVL
Location of ST elevations and depressions in lateral MI?
Elevations: I, aVL, V5, V6
Depressions: II, III, aVF
Location of ST elevations and depressions in posterior MI?
Elevations: V7, V8, V9
Depressions: V1-V3
Location of ST elevations and depressions in R ventricular MI?
Elevations: V1, V4R
Depressions I, aVL
Artery affected in anterior MI?
Left anterior descending
Artery affected in septal MI?
Left anterior descending
Artery affected in inferior MI?
R coronary artery (80%), L circumflex (20%)
Artery affected in lateral MI?
L circumflex
Artery affected in posterior MI?
R coronary artery or L circumflex
Artery affected in R ventricular MI?
R coronary artery
List the 4 cardiac markers? Which is most sensitive?
Myoglobin
CK-MB
Cardiac Trop I*
Cardiac Trop T
Initial elevation, peak elevation, and return to baseline for myoglobin?
Initial: 1-4 hours
Peak: 6-7 hours
Return: 18-24 hours
Initial elevation, peak elevation, and return to baseline for CK-MB?
Initial: 4-12 hours
Peak: 10-24 hours
Return: 48-72 hours
Initial elevation, peak elevation, and return to baseline for cardiac trop I?
Initial: 3-12 hours
Peak: 10-24 hours
Return: 3-10 days
Initial elevation, peak elevation, and return to baseline for cardiac trop T?
Initial: 3-12 hours
Peak: 12-48 hours
Return: 5-14 days
In addition to EKG and serial troponins, what labs should be considered in chest pain?
- CBC (anemia may be a cause)
- CXR (may show pulmonary edema or other causes of chest pain)
- Electrolytes, BUN, creatinine, Mag (may effect Rx regimens)
- Echocardiogram (usually after admission to look for regional wall motion abnormality)
- Stress testing (either exercise or chemically-induced exertion to look for EKG changes and/or decreased radionuclide uptake in the ischemic region)
- Coags
+/- D-Dimer, BNP, T&S, LFTs, lipase
How is ACS diagnosed?
Cardiac catheterization
Features of the history that strongly suggest ACS?
Exertional pain or pressure Exertion shortness of breath History of vascular disease Strong cardiac family history Prior MI's
Features of the EKG that strongly suggest ACS?
ST elevation of 1+ mm in 2 contiguous limb leads (high lateral - I, aVL, inferior: II, III, aVF) or 2+ mm elevations in the precordial leads (anterior - V1, V2, V3, lateral - V4, V5, V6)
Rx ACS?
- ABC, IV access, O2, cardiac monitor
- Morphine, oxygen, nitroglycerin , aspirin, beta-blockers to control HR and blood pressure if needed
- If confirmed, given anti-thrombin therapy (heparin) and anti-platelet therapy (aspirin or IIb/IIIa inhibitor)
- If persistent ST-elevations -> revascularization (thrombolytics or angioplasty in cath lab)
- Without ST-elevations -> angiogram when appropriate
Cardiac enzyme testing will be negative in patients with angina. ___ is needed to discover any partially occluded coronary arteries.
Functional testing
What are the top 5 do-not-miss chest pain diagnoses?
- ACS
- PE
- Aortic Dissection
- Tension pneumothorax
- Esophageal rupture (Boerhaave’s syndrome)
Clinical features of tension pneumothorax?
JVD, tracheal deviation away from PTX, ipsilateral hyper-resonance to percussion/absent breath sounds, respiratory distress, hypotension
Rx tension pneumothorax?
Large bore needle (14 g) 2nd IC space midclavicular line for needle decompression -> convert to chest tube
Clinical features of esophageal rupture?
History of severe retching and vomiting followed by excruciating retrosternal chest and upper abdominal pain
SubQ emphysema, L PTX/pleural effusion, mediastinal widening/emphysema on CXR
Dx esophageal rupture?
Gastrograffin swallow/EGD/CT
Rx esophageal rupture?
IVFs
ABX
Surgical consult
Symptoms associated with ACS vs. CHF vs. PNA vs. PE vs. MSK
ACS: SOB, N/V (before or after CP), diaphoresis, palpitations
CHF: DOE, LEE, PND, orthopnea
PNA: cough, fever/chills
PE: calf pain/swelling, hemoptysis
MSK: trauma/heavy lifting, cough
Risk factors for cardiac problems?
CAD/PVD HTN DM HLD Smoking Family hx of early CAD (males 55 or earlier, females 65 or earlier) Cocaine use (previous or current)
Important physical exam steps in chest pain?
Neck: JVP, carotid bruit, carotid upstroke
Heart: S4, new MR murmur, rub, PMI
Lungs
Chest wall: reproducible pain, rashes/skin lesions
Abdomen
Extremities: edema, asymmetry, tenderness, distal pulses
Highest positive likelihood ratio (rule in) for acute MI?
CP radiating to R arm or shoulder
How is TIMI risk score used?
Primarily to determine aggressiveness of work-up, not discharge
MOA of aspirin in ACS + dosing/administration?
Irreversibly acetylates platelet cyclo-oxygenase
162-324 mg PO chewed to maximize bioavailability
MOA of nitroglycerin in ACS + dosing/administration?
Dilates coronary vessels to decrease preload and afterload (and thus decrease myocardial O2 demand)
Ask about Viagra/other PDE5 inhibitors (true contraindication)
Sublingual: 0.4 mg (=400 mcg) Q5 min x3 if SBP >100
Paste: 0.5-1 inch across chest
IV drip: 10 mcg/minute and titrate Q5-10 minutes to chest pain free or if SBP decreases to <100