ECG Findings and Treatment for Pericarditis
The classic ECG findings in pericarditis include widespread ST-segment elevation with PR-segment depression, occurring in approximately 60% of cases, while treatment consists primarily of NSAIDs with colchicine as first-line therapy. 1, 2
ECG Findings in Pericarditis
Characteristic ECG Changes
- Widespread concave upward ST-segment elevation in multiple leads (typically I, II, aVL, aVF, V3-V6) 1, 2
- PR-segment depression (opposite to P wave polarity) 2
- ST-segment depression in lead aVR, frequently in V1, and occasionally in V2 2
- Absence of reciprocal ST depression (helps differentiate from acute coronary syndrome) 2
- In lead V6, pericarditis is likely if the J point is >25% of the height of the T wave apex (using PR segment as baseline) 2
Temporal Evolution of ECG Changes
- ECG changes are present in only about 60% of cases 1, 3
- Changes evolve dynamically and may be influenced by disease severity, timing of presentation, degree of myocardial involvement, and treatment 3
- Serial ECGs are important as changes may be absent initially but appear during new episodes of chest pain 3
Differential Diagnosis Considerations
- Unlike early repolarization, ECG changes in pericarditis evolve through characteristic stages 2
- To differentiate from STEMI: pericarditis shows widespread ST elevation without reciprocal changes 2, 4
- QRS widening and QT interval shortening in leads with ST elevation may suggest STEMI rather than pericarditis 4
Diagnostic Approach
Essential Diagnostic Criteria
- Diagnosis 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, 5
- ECG is recommended in all patients with suspected acute pericarditis (Class I recommendation) 1, 2
- Transthoracic echocardiography is recommended in all patients with suspected pericarditis 1
Laboratory Assessment
- Assessment of inflammatory markers (CRP, ESR, WBC) is recommended 1, 5
- Cardiac biomarkers (troponin, CK) should be assessed to evaluate for myocardial involvement 1, 5
- Elevated cardiac biomarkers may indicate myopericarditis rather than isolated pericarditis 2
Treatment of Pericarditis
First-Line Treatment
- NSAIDs are the mainstay of therapy for idiopathic and viral pericarditis 5
- Colchicine should be added to NSAIDs to improve response and reduce recurrence rates 5, 6
- Outpatient management is recommended for low-risk patients 1
Treatment Monitoring
- Evaluation of response to anti-inflammatory therapy is recommended after 1 week 1, 2
- Serial ECGs should be performed to monitor disease evolution and response to treatment 2
Special Considerations
- Hospitalization should be considered for patients with high-risk features including elevated cardiac biomarkers suggesting myopericarditis 2
- Exercise restriction is recommended until symptom resolution and normalization of inflammatory markers 2
- Glucocorticoids should be reserved for patients with contraindications to first-line therapy, pregnancy beyond 20 weeks, or other systemic inflammatory conditions 6
Interventional Management
- Pericardiocentesis is indicated in cases of cardiac tamponade, suspected bacterial or neoplastic pericarditis, and symptomatic moderate to large effusions not responding to medical therapy 5
Common Pitfalls
- ECG changes may be absent in up to 40% of cases 5, 3
- Normal inflammatory markers do not exclude pericarditis, especially if the patient is already on anti-inflammatory treatment 5
- Diffuse ST elevation with ST depression in aVR and PR depression can also be seen in early repolarization and certain cases of STEMI 4, 7