Multifocal Atrial Tachycardia (MAT)

Multifocal Atrial Tachycardia (MAT)

David Ray Velez, MD

A Rapid Irregular Rhythm that Originates from Multiple Ectopic Foci in the Atrium

EKG Pattern

  • “Chaotic” Variable P Waves with ≥ 3 Different Morphologies (Different Sites of Origin)
  • Heart Rate > 100 bpm
  • *May Appear Similar to Atrial Fibrillation/Atrial Flutter with Transition to Frequent Premature Atrial Complexes (PACs)

Multifocal Atrial Tachycardia (MAT)

Associations

  • Pulmonary Disease (COPD) – Strong Association
  • Congestive Heart Failure (CHF)
  • Cardiac Disease
  • Hypokalemia
  • Hypomagnesemia

Treatment

  • Largely Treated by Management of Any Underlying Disorder
  • Correct Hypomagnesemia and Hypokalemia
  • Give Empiric Magnesium Even if Serum Magnesium is Normal
    • MgSO4 Bolus 2 g, Then Infuse 6 g Over 6 Hours
  • If Magnesium Fails: Metoprolol
    • Dose: 5 mg Every 5-10 Minutes as Needed (Maximum of 3 Doses)
    • Consider Verapamil if Beta-Blockers are Contraindicated Due to Severe Bronchospasm
  • *See Antiarrhythmic Pharmacology