Ischaemia and infarction
Wellens' syndrome
Deep or biphasic T waves in V2–V3 in a pain-free patient — critical LAD stenosis waiting to declare itself.
What you see
- Biphasic (type A) or deeply inverted, symmetrical (type B) T waves in V2–V3.
- Little or no ST elevation — less than 1 mm.
- Preserved R wave progression and no pathological Q waves.
- Normal or only slightly raised troponin, recorded when the patient is pain free.
Why it looks like that
The pattern is reperfusion, not infarction: a critically stenosed LAD occluded, then spontaneously opened. The T wave changes are the electrical memory of the ischaemic episode, which is why they appear once the pain has settled and can look deceptively benign.
What to do
- Admit and refer for inpatient angiography — this is a pre-infarction syndrome.
- Do not stress test. Provoking ischaemia in a critical LAD stenosis is how these patients arrest.
- Expect the T waves to evolve; their resolution does not mean the stenosis has gone.
The trap
The ECG is recorded between episodes, the troponin is normal, and the patient is discharged for an outpatient exercise test. Wellens' is a reason to keep someone in, not a reassuring finding.
More in ischaemia and infarction
Anterior STEMI
Convex ST elevation across the anterior chest leads — the LAD occlusion you cannot afford to sit on.
Inferior STEMI
ST elevation in II, III and aVF with reciprocal change in aVL — and a right ventricle you must check before giving nitrates.
Posterior myocardial infarction
Tall R waves and ST depression in V1–V3 — a STEMI viewed from behind, and easy to call NSTEMI by mistake.
De Winter T waves
Upsloping ST depression with tall symmetrical T waves in the chest leads — an LAD equivalent without the elevation.