Pericarditis Prehospital Management

Pericarditis, an inflammation of the pericardium (the sac surrounding the heart), can present with a range of symptoms that vary in severity. Recognising and managing pericarditis in the prehospital setting is crucial, as it can occasionally be a precursor to more serious conditions such as cardiac tamponade. This article provides an overview of the prehospital management of pericarditis, focusing on key recognition points and treatment strategies.

The Pericardium

The pericardium is a double-layered membrane that envelops the heart, offering structural support and functional protection. It plays a crucial role in maintaining the heart’s position, ensuring smooth cardiac movements, and preventing excessive dilation during various physiological states.

Fibrous Pericardium: A tough, external fibrous layer that surrounds the heart but remains unattached. This outer layer provides rigidity, limiting overexpansion of the heart, especially during situations of fluid overload or acute pericarditis.

Serous Pericardium: Composed of two delicate layers:

• Parietal Pericardium: Lines the internal surface of the fibrous pericardium.
• Visceral Pericardium (Epicardium): Covers the heart itself, providing a close, protective layer over the myocardium and great vessels.

Pericardial Space: The narrow space between the parietal and visceral layers contains 20-50mls of serous fluid, which reduces friction between these layers as the heart moves.

The pericardium serves three key physiological functions:

Mechanical Function: It limits excessive dilation of the heart chambers, helping to maintain the balance between pressure and volume within the ventricles. This compliance is essential during situations of increased preload. It also aids in atrial filling by maintaining proper chamber structure.

Barrier Function: The serous fluid within the pericardial space acts as a lubricant, minimising friction between the heart and surrounding structures during cardiac contractions. Additionally, the pericardium serves as a protective barrier against external infections and inflammations.

Anatomical Function: The pericardium anchors the heart in position through its connections to the diaphragm and the sternum. These ligamentous attachments prevent excessive movement of the heart within the thoracic cavity.

Pericarditis Pathophysiology 

Pericarditis is inflammation of the pericardium, the thin sac-like membrane surrounding the heart. The pathophysiology of pericarditis involves several mechanisms:

Inflammatory Response

The pericardium becomes inflamed due to various causes, including infections (viral, bacterial, or fungal), autoimmune conditions (like lupus), trauma, malignancies, or after a heart attack (post-myocardial infarction pericarditis). This inflammation can lead to swelling, increased vascular permeability, and the accumulation of inflammatory cells within the pericardium.

Pericardial Effusion

Inflammation may cause fluid to accumulate between the pericardial layers, known as pericardial effusion. This can increase pressure on the heart, potentially leading to cardiac tamponade, a life-threatening condition where the heart’s ability to pump blood is compromised

Fibrin Deposition

As part of the inflammatory response, fibrin can deposit in the pericardium, leading to thickening of the pericardial membrane. This can result in constrictive pericarditis, where the heart’s expansion is restricted, reducing its ability to fill properly during diastole.

Autoimmune and Hypersensitivity Reactions:

In cases like Dressler’s syndrome (post-cardiac injury syndrome), the body’s immune response to damaged heart tissue causes an inflammatory reaction in the pericardium.

Causes of Pericarditis

The majority of pericarditis cases are classified as idiopathic, meaning no specific underlying cause can be identified.

However, possible underlying causes of pericarditis include:

Risk Factors

The risk factors for pericarditis include:

Age: The average age of patients with acute pericarditis is between 41 and 60 years, with advanced age being a risk factor for bacterial pericarditis.

Sex: Males are at a higher risk of developing acute pericarditis.

Seasons: Idiopathic pericarditis tends to occur more frequently in the spring and autumn.

Steroid Use: Patients treated with steroids have a higher likelihood of experiencing recurrent pericarditis.

Additional risk factors for bacterial pericarditis can include diabetes, extensive burn injuries, heart surgery, chest trauma and pre-existing pericardial effusion,

Prognostic Risk Factors

Certain factors are associated with a worse prognosis and indicate the need for further investigation into an underlying cause, as well as inpatient admission.

While most cases of pericarditis are caused by viral infections and follow a relatively benign course, the presence of major or minor risk factors necessitates hospital admission and a thorough search for an underlying cause.

Major

• Fever > 38ºC
• Subacute onset of symptoms
• Large pericardial effusion
• Cardiac tamponade
• Poor response to treatment after one week of NSAID therapy

 Minor

• Myopericarditis (involvement of the heart muscle)
• Immunosuppression
• Trauma
• Use of oral anticoagulant therapy

Clinical Features

Chest Pain

Sharp, pleuritic (worse with inspiration), often retrosternal or left-sided. Radiates to the neck, shoulders, or trapezius ridge. Typically relieved by sitting up or leaning forward, and worsened by lying down.

Dyspnoea (Shortness of Breath)

Common, particularly with complications like pericardial effusion.

Fever

Usually low-grade, especially in infectious or inflammatory cases.

Cough

May accompany chest pain, due to irritation around the lungs.

Fatigue and General Weakness

Sometimes reported, especially in more severe cases.

Pericardial Friction Rub

A scratchy or squeaking sound heard over the heart, best heard at the left lower sternal border with the patient leaning forward.

Possible Signs of Cardiac Tamponade

• Hypotension
• Muffled heart sounds
• Raised jugular venous pressure (JVP)
• Pulsus paradoxus (a drop in systolic blood pressure >10 mmHg during inspiration).

Possible Signs of Pericardial Effusion

• Distant or muffled heart sounds.
• Reduced or obscured apex beat.
• Possible tubular breath sounds due to bronchial compression.

Investigations

For prehospital investigations of pericarditis, the focus is primarily on rapid assessment and stabilisation. Here’s a list of the key investigations that can be done in a prehospital setting:

Look for widespread ST-segment elevation and PR-segment depression across multiple leads. You can read more on Pericarditis ECG here. 

Auscultate for a pericardial friction rub, although this may be challenging in noisy or difficult environments.

Monitor for hypotension, tachycardia, and signs of shock, which could suggest complications like cardiac tamponade.

Assess for features of Beck’s triad (hypotension, raised JVP, muffled heart sounds) to identify potential cardiac tamponade

Limited use in prehospital settings, but if available, ultrasound can detect pericardial effusion.

Helps assess the size of the effusion and the presence of tamponade physiology (e.g., collapse of cardiac chambers during diastole).

Prehospital Management 

After confirming the diagnosis, assessing for underlying causes, and checking for evidence of pericardial effusion, treatment generally focuses on symptom relief, as acute idiopathic pericarditis is self-limiting in 70-90% of cases.

If an underlying cause is identified, treatment should target the specific condition.

All patients should receive general lifestyle advice, including restricting physical activity until symptoms resolve. Athletes are advised to avoid sports for three months and only resume after complete resolution of symptoms and normalised investigation results. Safety netting for signs of deterioration is crucial in all cases

Administer nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or paracetamol, to relieve chest pain, following your local protocols.

Do not administer anticoagulants (e.g., aspirin or clopidogrel) unless you strongly suspect acute coronary syndrome (ACS). Anticoagulants can exacerbate complications, including bleeding into the pericardial space or worsening pericardial effusion.

Encourage the patient to adopt a position of comfort, typically sitting upright or leaning forward, as this often reduces pain.

The decision to transport a patient with suspected pericarditis should be based on the presence of key red flags such as signs of cardiac tamponade (hypotension, raised JVP, muffled heart sounds), hemodynamic instability, severe or worsening symptoms, or poor response to treatment. Immediate transport is necessary for patients showing these signs, ideally to a facility with cardiology capabilities.

Even in stable cases, transport is recommended for further evaluation and to rule out complications. Continuous monitoring during transport is essential to detect any deterioration in the patient’s condition.

Differential Diagnoses

Other causes of pericarditis may be:

• Acute Coronary Syndrome (ACS)
• Pneumonia with Pleurisy
• Pulmonary Embolism
• Gastro-Oesophageal Reflux Disease (GORD)
• Costochondritis

Less common differential diagnosis may include:

• Aortic Dissection
• Intra-abdominal Pathology
• Pneumothorax

Key Points

Bibliography

British Heart Foundation (2020). Pericarditis. British Heart Foundation. https://www.bhf.org.uk/informationsupport/conditions/pericarditis

Dababneh, E. and Siddique, M.S. (2023). Pericarditis https://www.ncbi.nlm.nih.gov/books/NBK431080

NHS (2017). Pericarditis. nhs.uk. https://www.nhs.uk/conditions/pericarditis