What are the typical EKG (electrocardiogram) findings in patients with pericarditis?

ECG Findings in Pericarditis

The typical ECG findings in pericarditis include widespread ST-segment elevation and PR-segment depression, which are present in approximately 60% of cases. 1, 2

Classic ECG Findings

• Stage 1 (Early acute phase):

  • Widespread concave upward ST-segment elevation in multiple leads (typically I, II, aVL, aVF, V3-V6) 2
  • PR-segment depression (opposite to P wave polarity) 2
  • ST-segment depression in aVR, frequently in V1, and occasionally in V2 2

• Temporal evolution:

  • ECG changes in pericarditis are temporally dynamic and evolve through stages 2
  • Changes may be affected by therapy and vary significantly between patients 1
  • ECG may be normal at presentation or for days after the initial episode of chest pain 3

Diagnostic Value and Limitations

• ECG changes are present in only about 60% of pericarditis cases 1, 2, 3
• ECG changes imply inflammation of the epicardium, since the parietal pericardium itself is electrically inert 1
• ECG is recommended in all patients with suspected acute pericarditis (Class I recommendation) 1
• ECG changes are more common in patients with myopericarditis (60.7%) than in those with isolated pericarditis (24.5%) 4

Differentiating from Other Conditions

• Acute coronary syndrome:

  • Pericarditis shows widespread ST elevation without reciprocal changes 2
  • In lead V6, pericarditis is likely if the J point is >25% of the height of the T wave apex (using the PR segment as a baseline) 2

• Early repolarization:

  • Unlike early repolarization, ECG changes in pericarditis acutely evolve through characteristic stages 2
  • Early repolarization can mimic pericarditis with ST elevation in leads I and II, ST depression in aVR, and sometimes PR depression in inferior leads 5

Clinical Implications

• Serial ECGs should be performed to monitor disease evolution and response to treatment 2
• ECG changes may indicate concurrent myocardial involvement rather than simple pericarditis 4
• Presence of elevated cardiac biomarkers with ECG changes should prompt evaluation for myopericardial involvement 2

Diagnostic Approach

• Diagnosis of pericarditis requires at least 2 of 4 criteria: pericarditic chest pain, pericardial rubs, new widespread ST-elevation or PR depression on ECG, and pericardial effusion 1, 6
• Transthoracic echocardiography is recommended in all patients with suspected pericarditis 1, 6
• Elevated inflammatory markers (CRP, ESR, WBC) support the diagnosis but may be normal if the patient is already on anti-inflammatory treatment 6

Pitfalls to Avoid

• ECG may be normal despite active pericarditis, especially early in the disease course 3
• QRS widening and QT interval shortening in leads with ST-segment elevation may suggest acute myocardial infarction rather than pericarditis 7
• Patients with elevated cardiac biomarkers and ECG changes should be evaluated for myopericarditis 1, 2