= a type of ventricular tachycardia
-usually paroxysmal with runs lasting <90s
Unstable
-defibrillate if pulseless (indistinguishable from vfib)
-cardiovert or defibrillate* if unstable with pulse
*cardioversion may not work as the machine may not be able to synchronize with a polymorphic rhythm –> may need to defibrillate even if not pulseless
-do NOT give amio or procainamide – these worsen QT prolongation
Stable**
(1) give 2g magnesium sulfate over 2m
(2) increase HR in order to decrease QT interval
—-overdrive pacing (transvenous preferred) with rate for capture usually 110 or higher
—-chemical overdrive pacing via isoproterenol drip (beta1 & beta2 agonist) at 5 mcg/min (ONLY if acquired, NOT congenital)
(3) consider lidocaine (suppresses early after-depols and thus PVCs)
**May try cardioversion even if stable
Prolonged QT
(1) give 2g magnesium sulfate over 2m to prevent (or treat) torsades
(2) correct hypomagnesemia, hypokalemia, & hypocalcemia
-note: if pt found to have torsades, baseline QT prolongation is not always apparent
Non-Torsades Polymorphic VT
-usually due to ischemia and accompanied by chest pain and ischemic EKG findings
-as opposed to torsades, amio and beta blockers (ex: esmolol) are indicated
