Wellens Syndrome: Recognition and Urgent Management
Wellens syndrome is a critical ECG pattern indicating proximal left anterior descending (LAD) artery stenosis that requires urgent coronary angiography and revascularization to prevent extensive anterior wall myocardial infarction and death. 1, 2
ECG Characteristics
Wellens syndrome presents with two distinct patterns during a pain-free period in patients with recent intermittent chest pain 2, 3:
- Type A (25% of cases): Biphasic T waves in leads V2-V3 1, 2
- Type B (75% of cases): Deep, symmetrical T-wave inversions in leads V2-V4 (or V1-V4) 1, 4
Critical diagnostic features 5:
- Deep symmetrical T-wave inversion in anterior chest leads is often related to significant proximal LAD stenosis
- ECG changes typically occur during pain-free intervals
- Cardiac biomarkers are usually normal or minimally elevated 2, 3
- Preserved precordial R-wave progression (no pathologic Q waves) 6
Clinical Significance and Risk
This pattern represents a pre-infarction state with 75% risk of extensive anterior MI within weeks if not urgently treated 2, 3. The syndrome indicates critical (typically 95-99%) proximal LAD stenosis involving a large territory of myocardium at risk 2, 3, 6.
Immediate Management Algorithm
1. Recognition and Risk Stratification
- Obtain 12-lead ECG immediately at first medical contact 1
- Perform serial ECGs if initial tracing is equivocal 1
- Consider additional posterior leads (V7-V9) if clinical suspicion remains high with non-diagnostic standard ECG 1
- Classify as high-risk NSTE-ACS requiring urgent evaluation 1
2. Initial Stabilization
- Initiate continuous ECG monitoring for life-threatening arrhythmias 1
- Administer aspirin 162-325 mg (if no contraindications) 1
- Consider nitroglycerin for symptom relief if chest pain present 1
- Do NOT perform stress testing - this can precipitate acute MI 2, 3
3. Definitive Treatment
- Urgent coronary angiography with percutaneous coronary intervention (PCI) is the definitive treatment 1, 2, 3
- Primary PCI should be performed within 120 minutes of first medical contact 1
- Use radial access over femoral access to reduce bleeding and vascular complications 1
- For patients presenting within 12 hours of symptom onset, reperfusion therapy is indicated 1
4. Post-Intervention Care
- Implement dual antiplatelet therapy per standard post-ACS protocols 1
- Standard secondary prevention measures 1
Critical Pitfalls to Avoid
Do not confuse Wellens pattern with other causes of T-wave inversion 1:
- Cerebrovascular accidents (particularly subarachnoid hemorrhage)
- Cardiomyopathies (hypertrophic, takotsubo)
- Pulmonary embolism
- Pericarditis 5
Do not perform stress testing - this is contraindicated as it can precipitate acute anterior MI in the setting of critical LAD stenosis 2, 3, 6.
Do not discharge based on negative cardiac biomarkers alone - Wellens syndrome typically presents with normal or minimally elevated troponins during the pain-free period 2, 3.
Recognize that symptoms may be absent - some patients present with the ECG pattern without chest pain, but still require angiographic evaluation due to severe LAD stenosis risk 7.
Special Considerations
- Patients presenting 12-48 hours after symptom onset should still receive routine primary PCI 1
- Asymptomatic patients with Wellens ECG pattern warrant coronary angiography due to high risk of severe LAD stenosis 7
- Type B pattern may emerge after reperfusion of ischemic myocardium following stent placement 2
- Approximately 5% of patients with normal ECGs discharged from emergency departments are ultimately found to have acute MI or unstable angina, emphasizing the importance of serial ECGs and clinical correlation 5