Acute Coronary Syndrome
Definitions
Definitions
- Suspect ACS in these three presentations
- Rest angina, which is usually more than 20 minutes in duration
- New onset angina that markedly limits physical activity
- Increasing angina that is more frequent, longer in duration, or occurs with less exertion than previous angina
- Subtypes of ACS
- STEMI
- NSTE-ACS
- NSTEMI
- Elevated troponin in absence of ST elevation
- Unstable Angina (<4% ACS have normal biomarkers and EKG)
- New onset angina should be considered as unstable
- NSTEMI
Types of MI
Types of MI
- 1 = Spontaneous plaque rupture and thrombus
- 2 = Ischemic imbalance
- 3 = Sudden death (biomarkers unavailable)
- 4 = PCI/stent-related
- 5 = CABG-related
History
History
- Increase risk
- Radiation to both arms > right arm > left arm
- Diaphoresis
- Vomiting
- Worse on Exertion
- Decrease risk (Note: 7% of patients will have pleuritic chest pain and chest pain reproduced on palpation -> Atypical is common!)
- Reproduced on chest wall palpation (tenderness)
- Pleuritic pain
- Sharp/stabbing
- Positional
- Onset of pain
- Contraindications to
- Thrombolysis (see bottom of page)
- Anticoagulation (eg. currently on anticoagulation)
- Nitroglycerin (eg. PDE5-i, eg. Viagra)
- Metoprolol (eg. cocaine)
- Allergy to medications (eg. Aspirin)
Management
Management
- ABC
- Vitals
- Cardiac/oxygen monitor and IV x2
- Oxygen for sat >90%
- Focused history (AMPLE), include above
- Focused physical exam
- Rule out cardiogenic shock (hypotension, poor perfusion)
- Rule out heart failure (S3/S4, edema, distended liver)
- 12-lead ECG (repeat if non-diagnostic)
- Consider CXR (r/o pneumothorax, pneumonia, aortic dissection, esophageal rupture)
- Initial Troponin with repeat (3h for highly sensitive assay or 6h for sensitive assay from onset of chest pain)
- Only 1 Troponin needed if isolated CP >12hrs prior to ED visit and are symptom free for 12hrs prior to their ED visit
- Emergent cardiogenic consultation if shock, heart failure, sustained V Tach
- Aspirin (non-EC) 325mg PO chew or by rectum if unable to take PO
- Labs: CBC, Trop, Chem 10 (K, Mg), INR
- If stable
- *If chest pain, no hemodynamic compromise (RV infarct), and no PDE5i, Nitroglycerin 0.4mg (or 1 spray) SL q5mins x3
- *If no heart failure/hemodynamic compromise/bradycardia/severe asthma/cocaine, Metoprolol 25mg PO
- Consider Fentanyl 25mcg IV or Morphine 2.5mg IV q5 mins (for severe pain, avoid if possible)
- Atorvastatin 80mg PO daily
EKG
EKG
- Compare with previous
- If suspicious, consider Serial EKG q10-15mins and URGENT formal echocardiography by cardiologist (r/o wall motion abnormalities suggestive of MI)
- STEMI (or equivalent need for urgent repurfusion)
- ST segment elevations at J point in 2 contiguous leads >1mm in all leads except V2 and V3
- Men <40yo, ≥2.5 mm in V2 and V3
- Men >40yo, ≥2 mm in leads V2 and V3
- Women ≥ 1.5 mm ST elevation in V2 and V3
- ST segment elevations at J point in 2 contiguous leads >1mm in all leads except V2 and V3
- Non-STEMI
- ST segment depressions or deep T wave inversions without Q waves or no ECG changes
- Unstable Angina
- No EKG changes
Risk of Treatment
Risk of Treatment
- CRUSADE risk of bleeding post-MI
- Consider less invasive treatment in STEMI/NSTEMI with high risk of bleeding
STEMI or Equivalent
STEMI or Equivalent
- Reperfusion + Dual antiplatelet + Anticoagulant
- Primary PCI (within 90 mins of medical contact) + Ticagrelor 180mg + UFH 50-70 units/kg IV (max 5000 units)
- If PCI unavailable, <120mins of first medical contact, <12h symptom onset (unless ongoing symptoms), no contraindications (see at bottom of page)
- Fibrinolysis (goal 30mins) + Clopidogrel 300mg (75mg if age ≥ 75) + anticoagulation [Enoxaparin 30mg IV (adjust for renal and age ≥ 75) or UFH (if possible PCI later)]
- If PCI unavailable, <120mins of first medical contact, <12h symptom onset (unless ongoing symptoms), no contraindications (see at bottom of page)
- Primary PCI (within 90 mins of medical contact) + Ticagrelor 180mg + UFH 50-70 units/kg IV (max 5000 units)
- If no reperfusion indicated >12h onset of symptoms for Fibrinolysis or >24h for PCI, start Ticagrelor 180mg + Enoxaparin or UFH
- Glycoprotein IIb/IIIa Inhibitors [eg. Abciximab (Reopro), Eptifibatide (Integrilin), Tirofiban (Aggrastat)] may be given in high risk patients or continued ischemia as determined by the treating cardiologist
NSTEMI or Unstable Angina
NSTEMI or Unstable Angina
- Consider dual antiplatelet (Ticagrelor 180mg) + anticoagulant (enoxaparin or heparin if possible PCI later) for confirmed ACS with high risk of recurrent ischemia
- Consider PCI +/- GP IIb/IIIa inhibitor, especially in evidence of persistent ischemia (pain or EKG changes)
- No evidence for fibrinolysis
Low Risk (unlikely ACS)
Low Risk (unlikely ACS)
- Consider early discharge if negative EKG, troponin and low-risk ACS
Post-MI
Post-MI
- Lifestyle changes
- Modifiable risk factors (DLP, HTN, DM)
- Stop smoking
- Weight management
- Physical activity (Consider rehab)
- Medications
- ASA 81mg (or Clopidogrel 75mg if ASA intolerance)
- May consider dual antiplatelet therapy in subset (stent)
- May consider low-dose rivaroxaban 2.5mg PO BID with aspirin in very high risk CV events with low risk bleeding
- High-intensity Statin (eg. Rosuvastin 20-40mg daily, Atorvastatin 80mg daily)
- ACEI (or ARB), especially if anterior MI, heart failure or LVEF ≤40%
- Beta-blocker, especially if heart failure or LVEF ≤40%
- Consider switch to longer-acting (eg. Bisoprolol 2.5-20mg PO daily to maintain HR<70 and sBP>90mmHg)
- ASA 81mg (or Clopidogrel 75mg if ASA intolerance)
- Monitor for post-MI complications
- Pericarditis (10%)+/- pericardial effusion
- Suspect in pleuritic chest pain, fever, leukocytosis
- Aspirin or colchicine
- If >4w (Dressler's Syndrome) consider NSAIDs and/or corticosteroids
- LV free wall rupture (3%)
- VSD (1-2%)
- Papillary muscle rupture (1%)
- Pericarditis (10%)+/- pericardial effusion
References:
- RACGP 2017. https://www.racgp.org.au/afp/2017/november/troponin-testing/
- AAFP 2017.
- AAFP 2016. http://www.aafp.org/afp/2016/0615/p1008.html
- LITFL 2016. https://lifeinthefastlane.com/ccc/acute-coronary-syndromes/
- EMcrit 2015. https://emcrit.org/wp-content/uploads/2015/03/Who-to-PCI-by-Smith-and-Weingart.pdf
Fibrinolysis
Fibrinolysis
Absolute contraindications
- History of any intracranial hemorrhage
- History of ischemic stroke within three months (unless acute ischemic stroke seen within three hours, which may be treated with thrombolytic therapy)
- Presence of a cerebral vascular malformation or a primary or metastatic intracranial malignancy
- Symptoms or signs suggestive of an aortic dissection
- A bleeding diathesis or active bleeding, with the exception of menses
- Significant closed-head or facial trauma within three months
Relative contraindications
- Blood pressure >180 mmHg systolic and/or >110 mmHg diastolic
- History of ischemic stroke more than three months previously
- Dementia
- Any known intracranial disease that is not an absolute contraindication
- Traumatic or prolonged (>10 min) cardiopulmonary resuscitation
- Major surgery within three weeks
- Internal bleeding within four weeks or an active peptic ulcer
- Noncompressible vascular punctures
- Pregnancy
- Current warfarin therapy
- For streptokinase or anistreplase - a prior exposure (more than five days previously) or allergic reaction to these drugs
Causes of elevated troponin
Causes of elevated troponin
- Cardiac
- Contusion/surgery/procedure
- Infiltrative/inflammatory disease
- Aortic dissection
- Aortic valve disease
- Cardiomyopathy
- Tachyarrhthmias
- Noncardiac
- Extreme exertion/Rhabdomyolysis
- Pulmonary embolism
- Renal failure
- CVA, subarachnoid hemorrhage
- Critically ill (respiratory failure, sepsis)