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Cardiovascular

Acute Pericarditis

Acute pericarditis is inflammation of the pericardium causing sharp pleuritic and positional chest pain, with or without an effusion; diagnose it while excluding acute coronary and other life-threatening chest-pain causes, then risk-stratify for secondary disease, tamponade and myopericarditis.

In a nutshell

Acute pericarditis causes sharp pleuritic chest pain that is worse lying flat and better sitting forward, often with a friction rub and widespread ECG changes. Exclude ACS and other chest-pain emergencies, perform echocardiography, risk-stratify for admission, then treat uncomplicated inflammation with aspirin or an NSAID plus colchicine; tamponade needs urgent drainage.

Classic presentation

Sharp positional pleuritic chest pain after an infection, relieved by sitting forward, with widespread concave ST elevation or PR depression and possibly a friction rub.

Key points

  • Pericarditis is diagnosed clinically from at least two compatible features: characteristic pain, a friction rub, typical ECG changes or a new or worsening effusion.
  • Diffuse ECG change does not by itself exclude ACS; interpret the ECG with troponin, symptoms and risk.
  • Use echocardiography to identify an effusion, tamponade physiology and ventricular dysfunction; an effusion is not required for pericarditis.
  • Treat uncomplicated disease with aspirin or an NSAID plus colchicine, gastroprotection where appropriate and activity restriction, following current BNF guidance.
  • Fever, subacute onset, large effusion, tamponade, myocardial involvement, immunosuppression or treatment failure are high-risk features needing admission or specialist assessment.
  • Worsening breathlessness, hypotension, syncope or raised JVP suggests tamponade and needs urgent drainage rather than more analgesia.

First-line investigation

12-lead ECG, troponin, inflammatory markers and urgent transthoracic echocardiography, while maintaining an acute chest-pain differential.

Management

Exclude dangerous chest-pain causes

  • Assess ACS, pulmonary embolism, dissection, pneumothorax and tamponade in parallel with the pericarditis diagnosis; arrange urgent echo when haemodynamics or effusion are concerning.1,2

Treat inflammation

  • Use aspirin or an NSAID plus colchicine, gastroprotection where appropriate and BNF-guided prescribing, with activity restriction while inflammation is active.1,4

Admit high-risk presentations

  • Admit or discuss urgently with cardiology for fever, subacute onset, large effusion, tamponade, myocardial involvement, immunosuppression, anticoagulation, trauma, suspected secondary cause or non-response.1

Treat cause and drain complications

  • Treat a specific cause and arrange urgent specialist drainage for tamponade or a clinically indicated effusion; purulent, traumatic or dissection-related haemopericardium may need surgery.1,5

Confirm remission and prevent recurrence

  • Review symptoms, inflammatory activity, ECG and echo when needed, give urgent safety-netting and refer recurrent, refractory or myopericardial disease for specialist management.1,2,3

Exam traps

  • Widespread ST elevation and PR depression support pericarditis, but regional changes, reciprocal changes or a concerning troponin need an ACS pathway.
  • A normal chest radiograph or absent effusion does not exclude pericarditis.
  • Troponin elevation suggests myocardial involvement and changes the activity and specialist pathway; it is not automatically a simple pericarditis episode.
  • A rapidly accumulating effusion can tamponade without a large cardiac silhouette.
  • Post-MI anti-inflammatory choice needs specialist and BNF consideration; aspirin is generally preferred over other NSAIDs in that context.

Illustrations

ECG in acute pericarditis12-lead ECG showing widespread concave ST-segment elevation and PR depression across multiple leads, with a caution that acute coronary syndromes can overlap and require clinical correlation.James Heilman, MD, Wikimedia Commons · CC-BY-SA-3.0
Pericardial effusion progressing to tamponadeDiagram showing inflammatory fluid accumulating in the pericardial space, then compressing the right-sided chambers as intrapericardial pressure rises.PassFinals · original
Large pericardial effusion on chest radiographChest radiograph showing a smooth enlarged cardiac silhouette from a large effusion, with a caption warning that a normal radiograph does not exclude a rapidly accumulating effusion.James Heilman, MD, Wikimedia Commons · CC-BY-SA-3.0

Key sources

  1. ESC 2025 Guidelines for the management of myocarditis and pericarditis (Current specialist guideline for inflammatory myocardial and pericardial syndromes, including diagnosis, risk stratification, anti-inflammatory treatment, effusion, tamponade, recurrence and constriction; published 29 August 2025.)
  2. NHS: Pericarditis (Current NHS information on symptoms, assessment, treatment, urgent chest-pain advice and recovery.)
  3. British Heart Foundation: Pericarditis (UK cardiac charity clinical information on symptoms, causes, tests, anti-inflammatory treatment, recovery and return to exercise.)
  4. BNF online: current aspirin, NSAID, colchicine and corticosteroid prescribing (Use the current BNF and local cardiology protocol for anti-inflammatory choice, dose, duration, tapering, contraindications, interactions, gastroprotection and renal monitoring; no fixed dose is reproduced here.)
  5. NHS Trust information: Pericardiocentesis (UK NHS information describing ultrasound or X-ray guided drainage of pericardial fluid, particularly for tamponade; specialist procedural protocols take precedence.)

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.