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This is a clinician-written, evidence-based summary aligned to the 2026 MLA Content Map. It is intended for medical students and junior doctors preparing for the UKMLA. Always cross-reference with NICE guidance, local protocols, and clinical judgement.
The Bottom Line
- Pericarditis = inflammation of the pericardium — most common cause is viral (or idiopathic)
- Sharp pleuritic chest pain, worse lying flat, relieved by sitting forward
- ECG: widespread concave (saddle-shaped) ST elevation + PR depression (all leads except aVR and V1)
- Treatment: NSAIDs (ibuprofen 600 mg TDS) + colchicine 500 mcg BD for 3 months (reduces recurrence by 50%)
- Red flags: large pericardial effusion, haemodynamic compromise (tamponade), fever >38°C unresponsive to NSAIDs
Overview
Acute pericarditis is inflammation of the pericardial sac. In developed countries, most cases are viral (Coxsackie B, echovirus, adenovirus) or idiopathic (presumed viral). Other causes include post-MI (early pericarditis within 24–72 hours or Dressler syndrome at 2–10 weeks), uraemia, autoimmune (SLE, rheumatoid), malignancy, tuberculosis (important cause worldwide), drugs (procainamide, hydralazine, isoniazid), and post-cardiac surgery (postpericardiotomy syndrome). Diagnosis requires at least 2 of 4 criteria: typical chest pain, pericardial friction rub, characteristic ECG changes, or new/worsening pericardial effusion.
Epidemiology
Pericarditis accounts for approximately 5% of presentations to the emergency department with non-ischaemic chest pain. It is most common in young men (20–50 years). Viral/idiopathic pericarditis has an excellent prognosis with recurrence rates of approximately 30% (reduced to 15% with colchicine). TB pericarditis is more common in immunocompromised patients and in patients from endemic regions. Post-MI pericarditis (Dressler syndrome) has become less common with early reperfusion strategies.
Clinical Features
Symptoms
Sharp, pleuritic chest pain — central or left-sided, may radiate to trapezius ridge (pathognomonic radiation)
Pain worse on lying flat and on inspiration
Pain relieved by sitting forward
Low-grade fever and malaise
Preceding viral illness (1–2 weeks before) common
Dyspnoea (if large effusion or tamponade)
Signs
Pericardial friction rub — scratchy, superficial sound best heard at left sternal edge with patient leaning forward (may be transient)
Tachycardia
Low-grade pyrexia
Muffled heart sounds (if significant effusion)
Raised JVP, hypotension, pulsus paradoxus (tamponade — Beck triad)
Investigations
First-line
ECGWidespread concave (saddle-shaped) ST elevation + PR depression in most leads (except aVR and V1 which show ST depression and PR elevation). No reciprocal changes (unlike STEMI). T-wave inversion occurs later (stage III)
BloodsRaised CRP/ESR (universal), mildly elevated troponin in ~30% (myopericarditis). FBC, U&Es, LFTs, TFTs
EchocardiogramAssess for pericardial effusion. May be normal in dry pericarditis. Essential to exclude tamponade
Second-line
Chest X-rayUsually normal. Large effusion → globular (water-bottle) cardiomegaly
High-sensitivity troponinMild elevation suggests myopericarditis (pericarditis + myocardial involvement)
Specialist
Cardiac MRIPericardial enhancement on late gadolinium — confirms pericarditis, assesses myocardial involvement
PericardiocentesisIf large effusion or tamponade; send fluid for cytology, culture (including TB), protein/LDH
CT chestIf TB or malignancy suspected; pericardial thickening, calcification (constrictive pericarditis)
1
First-line (viral/idiopathic)
- NSAIDs: ibuprofen 600 mg TDS or aspirin 750–1000 mg TDS for 1–2 weeks, then taper over 3–4 weeks
- Colchicine 500 mcg BD (≤70 kg: 250 mcg BD) for 3 months — reduces recurrence by ~50% (COPE/ICAP trials)
- Gastroprotection with PPI if using NSAIDs
- Activity restriction: avoid strenuous exercise until symptoms resolve and CRP normalises (athletes: 3 months)
2
Second-line (recurrent or NSAID-resistant)
- Low-dose corticosteroids (prednisolone 0.25–0.5 mg/kg/day) — only if NSAIDs + colchicine fail; slow taper over months
- Avoid corticosteroids in first episode (increase recurrence risk)
3
Special situations
- Post-MI pericarditis: aspirin preferred (avoid NSAIDs which impair myocardial healing). Avoid anticoagulants if haemopericardium risk
- TB pericarditis: full anti-TB therapy (RIPE regimen) for 6 months
- Uraemic pericarditis: intensify dialysis
- Tamponade: urgent pericardiocentesis
Complications
- Pericardial effusion: Serous, haemorrhagic, or purulent — may progress to tamponade
- Cardiac tamponade: Life-threatening — requires urgent pericardiocentesis
- Recurrent pericarditis: ~30% without colchicine; usually self-limiting but can be debilitating
- Constrictive pericarditis: Rare late complication — thickened, fibrosed, calcified pericardium restricting ventricular filling. More common post-TB or post-radiation
- Myopericarditis: Myocardial involvement with troponin rise and wall motion abnormalities
UKMLA Exam Tips
- 1Pericarditis ECG: widespread saddle-shaped ST elevation WITHOUT reciprocal ST depression = key differentiator from STEMI
- 2PR depression is relatively specific for pericarditis — rarely seen in STEMI
- 3Pain relieved by sitting forward + trapezius ridge radiation = classic pericarditis descriptors
- 4Colchicine is the key add-on to NSAIDs — reduces recurrence by 50%
- 5Dressler syndrome = post-MI pericarditis at 2–10 weeks, autoimmune mechanism, treat with aspirin (not NSAIDs)
- 6Avoid corticosteroids in first episode — they INCREASE recurrence risk
practicetest your knowledge on acute pericarditisApply what you've learnt with UKMLA-style questions from the iatroX Q-Bank — cardiovascular and beyond.
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