46. Chest pain Flashcards
ACS.
- STEMI* (ST elevation + troponin rise)
- NSTEMI (no ST changes; troponin rise)
- Unstable angina (no ST changes or troponin rise)
*New LBBB is considered equivalent to ST elevation in the context of acute cardiac-sounding chest pain
Post-MI complications
- Heart failure - acute or chronic
- Arrhythmias - especially VT, VF
- Mitral regurgitation
- Reinfarction or ongoing angina
- LV thrombus - emboli can cause CVA/ bowel ischaemia
- Pericardial effusion and tamponade (Dressler syndrome: 2 - 6 weeks later)
Heart block post-MI.
a) Cause
b) Recovery post- anterior MI
c) Recovery post- inferior MI
a) Ischaemia and oedema related to the infarct
b) Poor (if not in first week, highly unlikely to recover)
c) Good; can recover even a few weeks post-MI (observe for progression from 3rd degree, to 2nd, to 1st, to sinus)
Red vs. white thrombus
Red - rich in coagulation factors, more important in venous system/atria - treat with anticoagulation
White - rich in platelets; more important in arterial system - treat with antiplatelets
Chest pain: assessment
a) History
b) Examination
c) Investigations
a) - HPC: Onset (rest, exertion, other), duration (> 15 mins for ACS, < 12h for PCI), exacerbating/relieving factors (GTN, breathing, position, tenderness),
- PMHx: CV risk factors, etc.
-
b) Obs (O2, RR, HR, BP, temp)
General - pallor, sweating, shock
CV - pulse rate and rhythm, heart sounds (murmur?)
Resp - lung fields, expansion, etc.
Legs - tenderness, swelling (DVT, heart failure)
c) - Bedside: 12-lead ECG
- Bloods: FBC, CRP, UEs/creatinine, glucose, lipids, TFTs, amylase, LFTs
- Imaging: CXR (rule out pulmonary disease/heart failure), ?CTPA/leg USS (rule out PE/DVT)
Causes.
a) Cardiac
b) Respiratory
c) Other
a) ACS (> 15 mins), stable angina (< 15 mins), arrhythmias, structural heart disease (eg AS), aortic dissection, acute heart failure, pericarditis, tamponade
b) PE, pneumonia, pneumothorax
c) - MSK (tenderness) - costochondritis, rib fractures
- GI - reflux, dyspepsia (functional, PUD), oesophageal spasm, malignancy
- Psychogenic, panic attack, phaeochromocytoma
Chest pain: differentials (1)
a) Prodromal coryzal symptoms, followed by burning and tingling sensations in chest; then development of painful maculopapular rash on left side of chest, become vesicular then crust over
b) Sharp, constant sternal pain relieved by sitting forward, worse when lying on the left side and on inspiration, swallowing, and coughing. Also pyrexial
c) Sharp and constant left sub-mammary pain, SOB associated with tingling of the extremities and palpitations. Very anxious
d) Ankle swelling, tiredness, severe breathlessness and chest pain, with inspiratory crackles at lung bases, and wheeze present
e) Chest pain associated with palpitations, breathlessness, and syncope in a previously fit and healthy young person
f) Acute-onset breathlessness, pleuritic chest pain (worse on inspiration), cough, haemoptysis +/- collapse
g) Progressive SOB and pleuritic CP; stony dull percussion note and diminished breath sounds on L side.
h) Chest or shoulder pain, haemoptysis, dyspnoea, weight loss, appetite loss. Finger clubbing, lymphadenopathy
a) Shingles (herpes zoster)
b) Pericarditis/cardiac tamponade
c) Panic attack/psychogenic (tingling due to low CO2)
d) Acute congestive heart failure
e) Arrhythmia - likely SVT
f) PE (if collapse, likely massive PE = acute PE with obstructive shock or SBP <90 mmHg)
g) Pleural effusion
h) Lung Ca
Chest pain: differentials (2).
a) Sudden tearing chest pain radiating to the back; BP different in both arms, inequality in pulses, shocked
b) Central crushing chest pain come on at rest, lasting 30 mins. No ST elevation on ECG.
c) Unilateral, sharp, anterior chest-wall pain, exaggerated by breathing, tender on palpation. Recent URTI
d) Sub-sternal pain, worse at night, after meals and when bending or lying flat
e) Sudden-onset pleuritic pain and breathlessness; tachycardic, reduced breath sounds on left side
f) Cough, pleuritic chest pain and fever. Right MZ creps on auscultation.
a) Aortic dissection
b) NSTEMI/unstable angina (dependent on troponins)
c) Costochondritis
d) Dyspepsia - PUD, reflux, etc.
e) Pneumothorax (if tension: tracheal deviation, hypotension, raised JVP, etc.)
f) Pneumonia
When to suspect ACS.
a) Core feature
b) Supporting features
a) Pain in the chest or other areas (for example the arms, back, or jaw) lasting longer than 15 minutes.
b) Associated with:
- nausea and vomiting, sweating or breathlessness, or a combination of these.
- haemodynamic instability (for example the person has a systolic BP < 90)
Diagnosis of ACS in primary care.
a) Can be done if chest pain was more than how many hours ago?
b) ECG changes indicating ischaemia/previous infarct
a) 72 hours (plus no complications); otherwise admit to ED
b) Pathological Q waves, ST/T abnormalities, LBBB
Cardiac tamponade: Beck’s triad
Hypotension,
muffled heart sounds,
jugular venous distention (Beck’s Triad).
Also - pulsus paradoxus (decrease in palpable pulse and arterial systolic blood pressure of 10 mmHg on inspiration);
Type 1 vs. Type 2 myocardial infarction
Type 1: MI caused by atherothrombotic coronary artery disease and usually precipitated by atherosclerotic plaque disruption
Type 2: MI caused by a mismatch between oxygen supply and demand (no thrombus); may be precipitated by acute stress (eg. acute gastrointestinal bleed, sustained tachyarrhythmia) that leads to insufficient myocardial blood flow to meet its oxygen demands
Pericarditis.
a) Causes
b) Presentation
c) Investigations
d) Management
a) - Viral (coxsackievirus)
- Dressler syndrome: 2 - 10 weeks post-MI (more rarely post-heart surgery)
b) - Fever, pleuritic chest pain
- Pericardial friction rub
c) - ECG: widespread saddle-shaped ST elevation
- Bloods: FBC, CRP, ?cultures
- Imaging: CXR (flask-shaped heart), ECHO
d) - NSAIDs and colchicine
- Steroids if severe
- Pericardiocentesis if effusion (tamponade)
