What are the electrocardiogram (ECG) findings in pericarditis?

From the Guidelines

Pericarditis is characterized by widespread ST-segment elevation in most leads except aVR and V1, with concurrent PR-segment depression, as noted in the most recent guidelines 1. The ECG findings in pericarditis evolve through four stages, with the earliest and most common finding being diffuse ST elevation and PR depression.

• Stage 1 shows diffuse ST elevation and PR depression
• Stage 2 demonstrates normalization of ST and PR segments
• Stage 3 develops T-wave inversions
• Stage 4 shows resolution of T-wave changes or persistence of T-wave inversions These stages are supported by evidence from recent studies, including the 2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR guideline for the evaluation and diagnosis of chest pain 1. Additional ECG findings may include:
• Sinus tachycardia due to pain or inflammation
• Low QRS voltage if there's a significant pericardial effusion
• Electrical alternans, a beat-to-beat variation in QRS amplitude, which suggests cardiac tamponade It's essential to differentiate pericarditis from myocardial infarction, as both conditions can present with similar ECG changes, making clinical correlation crucial for accurate diagnosis, as highlighted in the European Heart Journal 1 and the Journal of the American College of Cardiology 1. The diagnosis of pericarditis is often suspected based on clinical presentation, ECG findings, and biological signs of inflammation, as noted in the European Society of Cardiology guidelines 1. In patients with suspected pericarditis, echocardiography and cardiac CT may show features suggestive of acute pericarditis, such as pericardial thickening or enhancement, and pericardial effusion, as reported in the Journal of the American College of Cardiology 1. Overall, the ECG findings in pericarditis are characteristic and evolve through distinct stages, making it essential to consider pericarditis in the differential diagnosis of chest pain, as emphasized in the American College of Cardiology/American Heart Association joint committee on clinical practice guidelines 1.

From the Research

ECG Findings in Pericarditis

The electrocardiogram (ECG) findings in pericarditis include:

• Widespread ST-segment elevation or PR depression, which are classic ECG manifestations of acute pericarditis 2, 3, 4, 5
• ST-segment elevation can be concave and diffuse, with a ratio of ST-segment elevation to T wave >0.24 in lead V6 4
• PR-segment depression with multilead ST-segment elevation and ST-segment depression in lead aVR 2
• QRS widening and QT interval shortening in leads with ST-segment elevation can help differentiate acute ST-segment elevation myocardial infarction from acute pericarditis 2
• ECG changes can be temporally dynamic and evolve rapidly during the course of disease, influenced by factors such as disease severity, time of presentation, and degree of myocardial involvement 3

Differentiation from Myocardial Infarction

To differentiate pericarditis from myocardial infarction, consider the following:

• ECG changes in pericarditis are often widespread and not limited to a specific coronary artery territory 2, 6
• Echocardiography and cardiac magnetic resonance imaging can help assess pericardial effusion, tamponade, and myocardial involvement 6, 3, 4, 5
• Troponin elevation can occur in both pericarditis and myocardial infarction, but is more commonly associated with myocardial involvement 5

Clinical Implications

ECG changes in pericarditis:

• Can be recorded in about one-quarter of patients with pericarditis 5
• May reflect concurrent myocarditis, which should be ruled out 5
• Are not associated with a worse prognosis in patients with pericarditis 5