Torsades de pointes: Difference between revisions
No edit summary |
|||
| Line 5: | Line 5: | ||
===Common Causes=== | ===Common Causes=== | ||
'''POINTES''' mnemonic: | '''POINTES''' mnemonic: | ||
*'''P'''henothiazines | |||
*'''O'''ther medications (ie TCAs) | |||
*'''I'''ntracranial bleed | |||
*'''N'''o known cause (idiopathic) | |||
*'''T'''ype I anti-arrhythmics (quinidine, procainamide, disopyramide) | |||
*'''E'''lectrolyte abnormalities (hypoK & hypoMag) | |||
*'''S'''yndrome of Prolonged QT (aka Long QT Syndrome) | |||
==Clinical Features== | ==Clinical Features== | ||
Revision as of 06:34, 25 February 2015
Background
- 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
Diagnosis
Differential Diagnosis
Treatment
Increasing HR decreases QT interval
- 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+
- 1-2gm IV over 1-2 min, repeat in 5-15min; then 1-2gm/hr (3-10mg/min) gtt
- Isoproterenol - Increases HR / AV conduction
- 2-8 mcg/min
- Overdrive Pacing - Atrial > Ventricular pacing
- Goal HR 90-120
- Defibrillation / synchronized cardioversion - Patient in extremis