Makindo Medical Notes

Related Subjects: |Atherosclerosis |Ischaemic heart disease |Assessing Chest Pain |Acute Coronary Syndrome (ACS): Complications |ACS - General |ACS - STEMI |ACS - NSTEMI |ACS - GRACE Score |ACS - ECG Changes |ACS -Cardiac Troponins |ACS - Post MI arrhythmias |ACS: Right Ventricular STEMI |ACS: Sgarbossa Criteria |Wellen's syndrome

⚠️ Because Wellens syndrome patients have critical narrowing of the LAD coronary artery, stress testing is contraindicated. It may precipitate acute MI and sudden cardiac death.

🔎 Introduction

• Wellens syndrome = a classic ECG pattern indicating imminent anterior MI due to critical LAD stenosis.
• Key to recognise in the ED – early intervention is lifesaving.

🧬 Aetiology

• Represents >90% stenosis of the LAD artery.
• Critical narrowing → high risk of complete occlusion & anterior wall STEMI.

⚙️ Pathophysiology

• Atherosclerotic plaque: High-grade LAD lesion causes intermittent reduced perfusion.
• Vasospasm: LAD spasm may contribute to transient ischaemia.
• Increased demand: Exercise/stress raises oxygen demand, worsening ischaemia.
• Hypoxia: Systemic hypoxaemia aggravates LAD compromise.

⚠️ Risk Factors

• Diabetes mellitus
• Hypertension
• Hyperlipidaemia / Hypercholesterolaemia
• Smoking
• Metabolic syndrome
• Family history of premature IHD
• Age & occupational stress

🧾 Clinical Presentation

• Chest pain (often anginal, may have settled by time of ECG).
• Anginal equivalents: arm pain, jaw pain, dyspnoea.
• May be asymptomatic → ECG is crucial.

📊 Investigations

• Bloods: FBC, U&E, LFTs, lipids.
• Troponin: May be normal or only mildly raised.
• ECG hallmarks:
  • Biphasic or deeply inverted T waves in V2–V3.
  • Can extend V1–V6 (critical LAD territory).
  • T wave normalisation + hyperacute waves = impending STEMI.
• Echocardiogram: Wall motion abnormalities in anterior wall.
• Coronary angiography: Gold standard for diagnosis & management planning.

🩺 Management

• Immediate Care: Admit CCU, oxygen if hypoxic, aspirin/clopidogrel, nitrates, beta-blockers (if not contraindicated).
• STEMI protocol: If ST elevation develops → manage as acute STEMI.
• Definitive: Early coronary angiography → PCI or CABG depending on anatomy.
• Avoid stress testing: Contraindicated due to risk of precipitating full infarct.

📌 Prognosis & Clinical Significance

• Untreated → very high risk of anterior wall MI within days to weeks.
• Early recognition + PCI/CABG = excellent outcome.
• Secondary prevention vital: BP & cholesterol control, diabetes optimisation, smoking cessation, antiplatelet + statin therapy.

🖼️ Classic ECG Examples

📚 References

• Wellens Syndrome – NCBI Bookshelf
• de Zwaan C, Wellens HJ. “Characteristic electrocardiographic pattern indicating critical LAD stenosis.” Am Heart J. 1982.

Exam Pearl: – Wellens = T-wave changes in V2–V3 + critical LAD stenosis + pain-free at time of ECG. – Never stress test a Wellens patient 🚫🏃.

Cases — Wellens’ Syndrome

• Case 1 — Type A (biphasic T-waves) 📉: A 56-year-old man presents with intermittent central chest tightness over 2 days, now pain-free. ECG: biphasic T-waves in V2–V3, no ST elevation. Troponin mildly raised. Diagnosis: Wellens’ syndrome (critical LAD stenosis, Type A pattern). Managed with hospital admission, antiplatelets, and urgent coronary angiography ± PCI. ⚠️ Stress testing contraindicated due to risk of infarction.
• Case 2 — Type B (deeply inverted T-waves) ⚠️: A 63-year-old woman with diabetes presents with recent exertional angina, now pain-free in ED. ECG: deeply inverted, symmetrical T-waves in V2–V4, preserved R-wave progression. Troponin borderline. Diagnosis: Wellens’ syndrome (Type B pattern). Managed with dual antiplatelet therapy, heparin, and urgent revascularisation planning.
• Case 3 — Missed diagnosis → infarction 🚨: A 60-year-old man is discharged after presenting with atypical chest pain and “nonspecific T-wave changes.” Two days later he returns with severe chest pain. ECG: anterior ST-elevation MI. Angiography: complete proximal LAD occlusion. Retrospective review: prior ECG showed Wellens’ T-wave inversions. Diagnosis: progression of untreated Wellens’ syndrome to LAD infarction. Teaching point: always recognise the pattern!

Teaching Point 🩺: Wellens’ syndrome is a pre-infarction state caused by critical proximal LAD stenosis. ECG patterns (seen in pain-free state): - Type A: biphasic T-waves in V2–V3. - Type B: deeply inverted, symmetrical T-waves in anterior leads. No Q waves, no loss of R-wave progression, little ST elevation. ⚠️ High risk of extensive anterior MI → requires urgent angiography/PCI, not stress testing. Troponin may be normal or only mildly raised.