How can I differentiate between pericarditis and other causes of chest pain in a primary care context?

In a primary care setting, differentiating pericarditis from other causes of chest pain relies primarily on a detailed clinical history and physical examination, supported by targeted investigations when necessary. Pericarditis typically presents with sharp, pleuritic chest pain that is often relieved by sitting forward and worsened by lying down or deep inspiration. This contrasts with angina, which is usually described as constricting discomfort precipitated by exertion and relieved by rest or glyceryl trinitrate (GTN) within minutes ¹.

Key clinical features suggestive of pericarditis include: chest pain that is sharp and positional, a pericardial friction rub on auscultation, and sometimes associated symptoms such as fever or recent viral illness. Unlike myocardial ischemia, pericarditis pain is not typically exertional and does not respond to GTN ¹.

Physical examination may reveal a pericardial rub, which is a distinctive auscultatory finding not present in other chest pain causes ¹.

Investigations in primary care should include a resting 12-lead ECG, which in pericarditis often shows widespread concave ST elevation and PR depression, differing from the localized changes seen in myocardial infarction or ischemia ¹. However, a normal ECG does not exclude pericarditis or other serious causes, so clinical judgment is essential ¹. Blood tests may show elevated inflammatory markers (e.g., CRP) and troponin can be mildly elevated in pericarditis but is more markedly raised in myocardial infarction ¹.

Other causes of chest pain such as musculoskeletal pain, gastroesophageal reflux disease, or psychogenic pain have distinct clinical features: musculoskeletal pain is often reproducible on palpation and related to movement; dyspepsia-related pain is associated with meals and may have gastrointestinal symptoms; psychogenic pain is often non-specific and associated with anxiety ¹.

Referral or urgent hospital assessment is warranted if there is suspicion of acute coronary syndrome, aortic dissection, pulmonary embolism, or if the diagnosis remains unclear after initial assessment ¹,².

Recent literature emphasizes the importance of clinical history and ECG in the outpatient diagnosis of chest pain emergencies, supporting guideline recommendations that initial assessment should focus on symptom characteristics and ECG findings to triage patients effectively (Winters and Katzen, 2006; McConaghy and Oza, 2013).