From the Guidelines
The diagnostic criteria for pericarditis include clinical presentation, ECG changes, echocardiography, and inflammatory markers.
Diagnostic Criteria
- Clinical presentation: chest pain that changes with inspiration and position, pericardial friction rub, and fever 1
- ECG changes: diffuse concave upwards ST segment elevation and PR segment depression 1
- Echocardiography: pericardial effusion, thickened pericardial layers, and wall motion abnormalities in myo-pericarditis 1
- Inflammatory markers: elevated CRP and/or ESR, and myocardial lesions (CK, troponins) 1
High-Risk Features
Certain clinical features at presentation may be associated with an increased risk of specific aetiologies and complications, including:
- Major risk factors: fever ≥38°C, subacute course, large pericardial effusion, cardiac tamponade, and failure of aspirin or NSAIDs 1
- Minor risk factors: pericarditis associated with myocarditis, immunodepression, trauma, and oral anticoagulant therapy 1
Imaging Modalities
Different imaging modalities can be used to diagnose pericarditis, including:
- Echocardiography: useful for detecting pericardial effusion and thickened pericardial layers 1
- Cardiac magnetic resonance (CMR): useful for detecting myocardial edema, thickening, and late enhancement, as well as pericardial effusions 1
- Computerized tomography (CT): useful for detecting pericardial thickening or enhancement, and for distinguishing between exudative and transudative pericardial fluid 1
From the Research
Diagnostic Criteria for Pericarditis
The diagnostic criteria for pericarditis include:
- Sharp, pleuritic chest pain that worsens when supine (≈90%) 2, 3
- New widespread electrocardiographic ST-segment elevation and PR depression (≈25%-50%) 2, 3
- A new or increased pericardial effusion that is most often small (≈60%) 2, 3
- A pericardial friction rub (<30%) 2, 3 At least two of these criteria are required for a diagnosis of pericarditis 2, 3.
Diagnostic Evaluation
A triage of pericarditis can be safely performed on the basis of the clinical and echocardiographical presentation 4. Specific diagnostic tests are not warranted if no specific aetiologies are suspected on the basis of the epidemiological background, history and presentation 4. High-risk features associated with specific aetiologies or complications include:
- Fever > 38 degrees C
- Subacute onset
- Large pericardial effusion
- Cardiac tamponade
- Lack of response to aspirin or a NSAID 4 A targeted diagnostic evaluation is warranted in acute and recurrent pericarditis, with a specific aetiological search to rule out tuberculous, purulent or neoplastic pericarditis, as well as pericarditis related to a systemic disease, in selected patients according to the epidemiological background, presentation and clinical suspicion 4.
Role of Imaging in Diagnosis
Transthoracic echocardiography should be performed in all patients with acute pericarditis to characterize the size of effusions and evaluate for complications 2, 3. Cardiac magnetic resonance imaging plays a unique role in the initial assessment of pericarditis, particularly in the Covid-19 era in light of the increasing incidence of myocarditis and pericarditis 5. The combination of information between advanced echocardiography and cardiac magnetic resonance imaging may have an important diagnostic role in this setting 5.