Related Subjects:
|ECG Basics
|ECG Axis
|ECG Analysis
|ECG LAD
|ECG RAD
|ECG Low voltage
|ECG Pathological Q waves
|ECG ST/T wave changes
|ECG LBBB
|ECG RBBB
|ECG short PR
|ECG Heart Block
|ECG Asystole and P wave asystole
|ECG QRS complex
|ECG ST segment
|ECG: QT interval
|ECG: LVH
|ECG RVH
|ECG: Bundle branch blocks
|ECG Dominant R wave in V1
|ECG Acute Coronary Syndrome
|ECG Crib sheets
๐ T Waves
- โก The T wave represents ventricular repolarisation.
- ๐งญ Normally, T waves are concordant with the QRS (same direction), except in aVR and V1 where inversion can be normal.
โ ๏ธ Abnormal T Wave Patterns
- ๐ Peaked T waves: Classic for hyperkalaemia (tall, narrow, โtent-shapedโ).
- โฌ๏ธ Flattened T waves: Seen in hypokalaemia, hypothyroidism, obesity, COPD.
- โฌ๏ธโฌ๏ธ Deep T wave inversion:
- Acute Coronary Syndrome (ischaemia)
- Left Ventricular Hypertrophy (strain pattern)
- Left Bundle Branch Block
- Hypertrophic Cardiomyopathy
- ๐บ Deep anterior T wave inversion: LAD stenosis, Subarachnoid haemorrhage (neurogenic T waves), Takotsubo cardiomyopathy.
- ๐ป Deep inferior T wave inversion: Suggests RCA stenosis.
๐ ๏ธ Action
- ๐งช Always check electrolytes (Kโบ, Mgยฒโบ, Caยฒโบ) and correct if abnormal.
- ๐ Consider ischaemia if inversion is new, deep, or localized to vascular territories.
- ๐ง Think of extra-cardiac causes (e.g. SAH, stress-induced cardiomyopathy) if distribution is atypical.
๐ก Teaching Pearls
โ๏ธ Hyperkalaemia โ tall tented T waves are often the first ECG change (progress to sine-wave if severe).
โ๏ธ Hypokalaemia โ flat T + U waves.
โ๏ธ Deep T inversion in anterior leads can be ischaemic or neurogenic โ always interpret in context!