Torsades de pointes: Difference between revisions

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===Common Causes===
===Common Causes===
'''POINTES''' mnemonic:
'''POINTES''' mnemonic:
**'''O'''ther medications (ie TCAs)
*'''O'''ther medications (ie TCAs)
**'''I'''ntracranial bleed
*'''I'''ntracranial bleed
**'''N'''o known cause (idiopathic)
*'''N'''o known cause (idiopathic)
**'''T'''ype I anti-arrhythmics (quinidine, procainamide, disopyramide)
*'''T'''ype I anti-arrhythmics (quinidine, procainamide, disopyramide)
**'''E'''lectrolyte abnormalities (hypoK & hypoMag)
*'''E'''lectrolyte abnormalities (hypoK & hypoMag)
**'''S'''yndrome of Prolonged QT (aka Long QT Syndrome)
*'''S'''yndrome of Prolonged QT (aka Long QT Syndrome)

==Clinical Features==
==Clinical Features==

Revision as of 06:34, 25 February 2015


  • Torsades de Pointes is a form of polymorphic VTach, where there is a gradual change in the amplitude and twisting of the QRS complexes around the isoelectric line
  • Associated with prolonged QT, which may be congenital or acquired.

Common Causes

POINTES mnemonic:

  • Phenothiazines
  • Other medications (ie TCAs)
  • Intracranial bleed
  • No known cause (idiopathic)
  • Type I anti-arrhythmics (quinidine, procainamide, disopyramide)
  • Electrolyte abnormalities (hypoK & hypoMag)
  • Syndrome of Prolonged QT (aka Long QT Syndrome)

Clinical Features


Torsades in 12-lead

Differential Diagnosis


Increasing HR decreases QT interval

  1. Magnesium sulfate - decreases calcium influx
    • 1-2gm IV over 1-2 min, repeat in 5-15min; then 1-2gm/hr (3-10mg/min) gtt
      • Danger of hypermagnesemia → depressed neuromuscular function, so monitor closely
      • Supplement with K+
  2. Isoproterenol - Increases HR / AV conduction
    • 2-8 mcg/min
  3. Overdrive Pacing - Atrial > Ventricular pacing
    • Goal HR 90-120
  4. Defibrillation / synchronized cardioversion - Patient in extremis

See Also