Pericarditis
Introduction
Pericarditis is inflammation of the pericardial sac that surrounds the heart. It can be acute, subacute or chronic. The diagnosis is often made when there is a combination of a typical chest pain, ECG findings and a pericardial rub on auscultation. However a sizeable minority of ECGs will be atypical or, in some cases, may be normal. Therefore often the diagnosis of pericarditis may be a clinical one based mostly on history and physical exam.
Causes of Pericarditis
Idiopathic (about 25%) - Most of these are probably viral
Malignancy (about 25%)
Infectious (Bacterial e.g. Streptococcus, Staphylococcus, TB or Viral e.g Mumps, EBV, Flu)
Autoimmune disorder or Immunosupressed e.g. Rheumatoid arthritis, SLE, sarcoidosis, scleroderma
Myocardial Infarction associated - acute or weeks to months later (Dressler syndrome)
Metabolic disorders e.g. uraemia, myxoedema
Trauma - blunt or penetrating, post radiotherapy.
Drugs e.g. Isoniazid, hydralazine, penicillin
Complications are rare and include;
Chronic pericarditis
Pericardial effusion
Cardiac tamponade
Constrictive pericarditis
Clinical Features
Symptoms
Pain
Retrosternal pain, sharp, worse on lying down, relieved by sitting forward. Can be pleuritic.
Can radiate to trapezius ridge (specific to pericarditis as phrenic nerve transverse the pericardium)
Systemic symptoms
Fever, chills, rigors, fatigue
Subjective shortness of breath
Palpitations
Signs
Signs of infection (if underlying cause)
Fever, hypoxia, tachycardia
Pericardial rub on ausculation
Signs of complications;
Constrictive pericarditis = signs of heart failure (ascities, peripheral oedema, pulm oedema, elevated JVP), pericardial knock.
Large pericardial effusion/Tamponade = Ewarts sign (dull percussion note in left lower lobe), Pulsus Paradoxus (drop of >10mmHg in SBP during inspiration)
High Risk Features
Fever
True Dyspnoea
A subacute course
Significant effusion or tamponade
Failure to respond to NSAID therapy
Patients on anticoagulants
Immunosupression
Recent trauma
Patients with evidence of myocarditis i.e. elevated troponin
Differential Diagnosis
Cardiovascular
Acute coronary syndrome
Myocarditis
Aortic Dissection
Gastro-intestinal
GORD
Gastritis/Oesophagitis
Mediastinitis
Oesophageal spasm
Respiratory
Pneumothorax
Pulmonary embolism
Pneumonia
Musculoskeletal
Costochondritis
Precordial catch syndrome
Muscular strain
Clinical Investigations
Bedside
ECG (abnormal in 90% of patients)
Diffuse concave ST elevation except aVR and V1.
PR depression except at aVR and V1 where the PR segment is elevated
VBG
POCUS
Echo - looking for complications e.g. effusion, tamponade, CCF
Laboratory
Troponin - elevated in 2 of the most common alternative diagnoses i.e. Myocarditis + Acute Coronary Syndrome
FBC - elevated WCC are common
CRP - will generally be elevated. Can be monitored along with symptoms to ensure resolution
U&E - ? underlying renal failure as cause of pericarditis
Depending on severity and possible aetiology may require blood cultures, viral screen, autoimmune screen etc. This tests should generally be arranged and followed up by in-patient teams
Given the relatively benign course associated with most cases of pericarditis in the developed world it is not necessary to search for aetiology unless symptoms are severe or fail to respond to NSAID therapy.
Radiology
CXR
primarily looking for complications e.g. large pericardial effusion or alternative diagnosis e.g. pneumothroax, pneumonia
Echo
if concerned regarding effusion, heart failure, myocarditis.
Not necessary if diagnosis of pericarditis is clear and troponin and physical exam non concerning
Management and Disposition
Initial Resuscitation
If patient presents requiring resuscitation you should be concerned
about more sinister pathology or severe complications
Specific Treatment
Treatment of acute pericarditis should be targeted as much as possible at the underlying aetiology
NSAIDS are mainstay of treatment. They treat the pain and the underlying inflammation. Continue until pain resolves and CRP normalises
Colchicine 600mcg BD alone or in combination with NSAIDS has been shown to decrease the recurrence rate of pericarditis
Glucocorticoids should be used for initial treatment of acute pericarditis only in patients with contraindications to NSAIDs
Strenuous exercise may trigger recurrence of symptoms; therefore, such activity should be avoided until symptom resolution and normalization of CRP.
Symptomatic Treatment
Symptoms are generally well controlled with regular NSAIDs
e.g. Ibuprofen 400mg TDS
Disposition
Most cases of pericarditis can be managed in the community with GP follow up
High-risk patients should be admitted to initiate treatment and continue the diagnostic evaluation
References
Burns A. Pericarditis[Internet]. Australia: Life in the fast lane; 2020 [cited 2020 Nov 4]. Available from: https://litfl.com/pericarditis-ecg-library/
Spangler S, O Brien TX, Gentlesk PJ. Acute Pericarditis[Internet]. Medscape; 2019 [cited 2020 Nov 4]. Available from: https://emedicine.medscape.com/article/156951-overview
Snyder MJ, Bepko J, White M. Acute Pericarditis: Diagnosis and Management[Internet]. The USA: The American Academy of Family Physicians; 2014 [cited 2020 Nov 4]. Available from: https://www.aafp.org/afp/2014/0401/p553.html
Dare LJ, Kendall J. Pericarditis[Internet]. United Kingdom: RCEM learning; 2018 [cited 2020 Nov 3]. Available from: https://beta.rcemlearning.co.uk/references/pericarditis/
This blog was written by Dr Lisa Ang and was last updated in November 2020
Before you go have another look at the clinical case and see have any of your answers changed.