Tag: troponin

Chest pain

Chest pain

Sam speaks to Dr Adele Pope, advanced cardiology trainee at Auckland Hospital, about how to attack the most common, and often the most uncertain, ward call.

Differential

  • Life threatening
    • ACS
    • PE
    • Dissection
    • Cardiac tamponade
    • Pneumonia
    • Pneumothorax
    • Oesophageal bleed
  • Heart
    • Pericarditis
  • Lungs
    • Mechanical (foreign body, surgical, chest drain, post-pleurocentesis)
  • Oesophagus
    • Reflux
    • Oesophagitis
    • Oesophageal spasm
  • MSK
    • Musculoskeletal
    • Costochondritis
    • Rib fracture
  • Below the chest
    • Upper abdominal pain
  • Above the chest
    • Anxiety

Approach

  • Eyeball the patient
  • ABCs
    • Calling a code
      • 777 (or your local hospital emergency number)
      • This is Sam, medical house officer. I need the adult resus team to attend North Shore Hospital, ward 10, room E3.
  • History
    • SOCRATES (site, onset, character, radiation, associated symptoms, timing, exacerbating factors, severity)
    • Previous similar episodes? History of exertion chest pain?
    • Diaphoresis
    • Shortness of breath
    • Review of systems
  • Identify risk factors
  • Vitals + Examination
    • General inspection + peripheries
    • Aiming to identify red flags of hypotension, reproducibility on palpation and respiratory issues
    • Abdomen, calves, catheter and drains (for completeness)
  •  ECG
    • Take your time and be systematic
    • Look at an old ECG
    • Ischaemic ECG defined as STEMI, or any T wave inversion, ST depression, Q waves.
    • Look for contiguous and reciprocal abnormalities.
    • T wave change normal variants occur in III, aVR, V1.
    • A repeat ECG in 15 minutes is useful to identify dynamic changes.
  • Consider investigations
    • FBC, U&E, troponin
    • CXR if failure or respiratory issues are within your differential (not so useful for ACS, but unlikely to harm)
  • Management
    • Call for help (code or at least registrar support)
    • Attach continuous monitoring e.g. defibrillator pads
    • Re-assess stability of the patient
    • Oxygen only if hypoxic
    • GTN spray
    • Opiate analgesia (IV morphine boluses ideally)
    • Determine bleeding risk
      • Identify any anti-platelet and anti-coagulation medicines in use
      • Post-operative status
      • Consider loading with aspirin 300 mg PO
  • Document
    • Review past notes
    • Basics (date/time/name/reason for review)
    • Positives and pertinent negatives
    • Impression and differential with justification. Have you eliminated life threatening conditions?
    • Consider TIMI or HEART score (acknowledging use outside of ED)
    • Clear and specific plan
    • Consider discussion with senior and escalation, especially if called back to patient again

Specificity of chest pain symptoms and examination findings [Evidence]

Fanaroff AC, Rymer JA, Goldstein SA, Simel DL, Newby LK. Does This Patient With Chest Pain Have Acute Coronary Syndrome?The Rational Clinical Examination Systematic Review. JAMA. 2015;314(18):1955–1965. doi:10.1001/jama.2015.12735
  • No single finding rules in or rules out acute coronary syndrome.
  • The most specific (convincing) symptoms of ACS were:
    • Pain radiation to both arms (specificity, 96%; LR, 2.6 [95% CI, 1.8-3.7]).
    • Pain similar to prior ischaemia (specificity, 79%; LR, 2.2 [95% CI, 2.0-2.6]).
    • Change in pain pattern over the prior 24 hours (specificity, 86%; LR, 2.0 [95% CI, 1.6-2.4]).
  • Moderately helpful:
    • Worse with exertion (specificity, 73-77%; LR, 1.5 – 1.8).
    • Diaphoresis (specificity, 79-82%; LR, 1.3 – 1.4).
    • Dyspnoea (specificity, 45%; LR, 1.1 – 1.3).
  • Unhelpful, but classical symptoms:
    • Response to nitroglycerin – improvement or lack of improvement had likelihood ratios approaching 1.0.
    • Pleuritic pain had an LR range of 0.35 to 0.61.
    • Palpitations LR 0.37 – 1.3.
  • Hypotension was the strongest clinical sign (LR, 3.9 [95% CI, 0.98-15]), though the CI was broad and did not exclude 1.0.
  • Of all risk factors, symptoms, and signs, pain reproduced by palpation lowered the likelihood of ACS most (LR, 0.28 [95% CI, 0.14-0.54]).
  • ECG abnormalities
    • ST elevation → STEMI
    • ST depression was most specific for ACS (LR, 5.3 [95% CI, 2.1-8.6]).
    • TwI was not so reliable (LR, 1.8 [95% CI, 1.3-2.7]).
    • Take your time and draw on the ECG, and if it looks concerning, call for help.

Tamponade

  • Causes
    • Infection
    • Trauma
    • Tumour
    • Aortic dissection
    • Cardiac surgery
  • Beck’s triad (suggestive of tamponade)
    • Hypotension
    • Jugular vein distension
    • Absent/distent heart sounds
  • Treatment is fluids and urgent pericardiocentesis

Troponin

  • TnI binds to actin to hold troponin-tropomyosin; lasts 7-10d
  • TnT: binds to tropomyosin; lasts 10-14d
  • Normally undetectable, ↑ suggests myocardial damage. Very sensitive + specific.
  • TnI and TnT can ↑ in renal failure and other ischaemic causes (rule out w/ Exercise Stress Test or angiography)
  • Rises 3 hours post-MI, persisting up to 7-14 days >66% increase = reinfarct