T wave changes

Evaluation

Types of T wave morphology

Normal negative T waves in III, AVR and V1 (upright T wave in III is more common).

• Normally upright in 1, 2, V3-V6
  • Normally inverted in AVR and V1
  • Sometimes inverted in III, aVF, aVL, V1
  • New upright T wave in V1 or T wave taller in V1 than in V6 is pathologic
  • Inversions in V2-V6 are usually pathologic
    • Exception is persistent juvenile T-wave pattern, usually limited to V1-V3, classically young Afro-Caribbean women
• Greater than 2/3 height of R wave is abnormal
• Morphology
  • Inverted, symmetric,
  • Transient changes suggests ischemia without infarction
  • Persistent changes suggests infarction (troponin elevation usually seen)
• Pseudonormalization
  • In presence of baseline TWI (within 1 month), reocclusion causes normalization of TWI
  • Should be interpreted as evidence of ischemia
• T wave alternans
  • Beat-to-beat variability in the amplitude OR shape of T waves
  • Highly suggestive of impending or recent torsades

New Tall T-wave in V1

• Loss of precordial T-wave balance when upright TW in V1 > upright TW in V6
• A form of hyperacute T-wave
• New Tall T-Wave in V1 (NTTV1) = upright T-wave in V1, especially with proven change from previous ECG
  • Concerning for ischemia, especially with ACS symptomology
  • Perform repeat ECGs
• Normal variants
  • Misplaced leads
  • LBBB
  • LVH
  • High left ventricular voltage

Differential Diagnosis

T Wave Inversions

• Normal in pediatrics
• Myocardial infarct (NSTEMI)
• Myocardial ischemia (Wellen's) - T waves go up, then down
• Hypokalemia - T waves go down, then up (or camel humped, one upright TW and upright U-wave in severe hypokalemia)
• Hyperkalemia
• Pulmonary embolism (RV strain)
• Pulmonary hypertension, acute or chronic
• Pulmonary disease - hyperventilation, pneumothorax, pneumonia
• LVH with strain pattern
• RVH
• Bundle branch block (both left and right)
• WPW
• Pericarditis (stage 3)
• CNS T waves (diffuse, deep)
• Arrhythmogenic right ventricular dysplasia (may also have epsilon wave)
• HOCM
• Paced rhythm
• Elevated intracranial pressure

Peaked T-waves

• MI (hyperacute T waves)
• Hyperkalemia
• Benign Early Repolarization
• De Winter's T waves (acute LAD occlusion)

See Also

• ECG Basics
• Mattu ECG Case: Aug 27, 2012