From the Guidelines
To rule out pericarditis, the initial laboratory evaluation should include routine blood tests, such as markers of inflammation (i.e., CRP and/or ESR), white blood cell count with differential count, renal function, liver tests, and myocardial lesion tests (CK, troponins) 1. The diagnostic workup for pericarditis involves a combination of clinical evaluation, imaging studies, and laboratory tests.
- The initial evaluation should include:
- Auscultation
- ECG
- Transthoracic echocardiography
- Chest X-ray
- Routine blood tests, including markers of inflammation (i.e., CRP and/or ESR), white blood cell count with differential count, renal function, liver tests, and myocardial lesion tests (CK, troponins) 1
- Additional testing, such as CT and/or CMR, may be recommended as second-level testing for diagnostic workup in pericarditis 1. The goal of these tests is to establish the diagnosis of pericarditis, identify potential causes, and rule out other cardiac conditions with similar presentations.
- The diagnosis of pericarditis remains primarily clinical, based on characteristic chest pain, friction rub, and ECG changes 1. It is essential to note that further testing is indicated in high-risk patients according to the clinical conditions 1.
- High-risk patients may include those with:
- Fever ≥ 38°C
- Subacute course (symptoms developing over several days or weeks)
- Large pericardial effusion (diastolic echo-free space ≥ 20 mm in width)
- Cardiac tamponade
- Failure of aspirin or NSAIDs 1
From the Research
Labs to Rule Out Pericarditis
To diagnose pericarditis, several laboratory tests can be used to support the diagnosis and rule out other conditions. These include:
- Electrocardiogram (ECG) changes, such as widespread ST-segment elevation, which can be recorded in about one-quarter of patients with pericarditis 2
- Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) to monitor inflammatory conditions 3, 4
- Complete blood count (CBC) to rule out infection or other conditions 4
- Cardiac enzymes, such as troponin, to assess for myocardial involvement 2
- Chest radiographs to evaluate for pericardial effusion or other cardiac abnormalities 4
- Echocardiogram with Doppler to assess for pericardial effusion and cardiac function 4
Additional Tests
In some cases, additional tests may be necessary to rule out other conditions or to assess for complications of pericarditis. These include:
- Cardiac magnetic resonance (CMR) to diagnose concurrent myocarditis 2
- Targeted etiologic search, such as viral or tuberculosis testing, to identify the underlying cause of pericarditis 5
Interpretation of Results
The results of these laboratory tests should be interpreted in the context of the patient's clinical presentation and medical history. For example, ECG changes may imply concurrent myocardial involvement rather than simple pericarditis 2. Similarly, elevated ESR and CRP levels can indicate an inflammatory condition, but may not be specific for pericarditis 3, 4.