• See Also
  1. Electrocardiogram
  2. Cardiac Electrophysiology Anatomy
  • Definitions
  1. U Wave
    1. EKG variably present wave occurring between the T and P Waves
    2. May represent delayed repolarization of the bundle branches or Purkinje Fibers
  • Findings
  • Normal
  1. U Wave has same polarity as T Wave
  2. U Wave best seen in precordial leads (esp. lead V3) at slow Heart Rates
  • Causes
  • Prominent U Wave
  1. Hypokalemia
    1. In Hypokalemia, may also appear as a biphasic T Wave in V1-3
  • Causes
  • Inverted U Wave (V2 to V5)
  1. Myocardial Ischemia
  2. Myocardial strain pattern
  3. Hypertension
  • Causes
  • Increased U Wave amplitude
  1. Digoxin (Digitalis)
  2. Quinidine
  3. Hypercalcemia
  4. Epinephrine
  5. Thyrotoxicosis
  • References
  1. Berberian (2024) Crit Dec Emerg Med 38(10): 13
  2. Mattu (2017) Crit Dec Emerg Med 31(3): 11