What is the treatment for polymorphic ventricular tachycardia (V-tach) with a pulse using cardioversion in unsynchronized mode?

From the Guidelines

For polymorphic ventricular tachycardia with a pulse, unsynchronized cardioversion (defibrillation) is the correct approach, with an initial energy of 120-200 joules biphasic or 360 joules monophasic, as recommended by the 2010 American Heart Association guidelines 1. When treating a patient with polymorphic ventricular tachycardia who has a pulse,

• deliver an unsynchronized shock at the initial energy level,
• do not attempt synchronized cardioversion for polymorphic ventricular tachycardia as the varying QRS morphology makes it difficult for the machine to synchronize,
• which could dangerously delay shock delivery, as noted in the 2004 ACC/AHA guidelines for the management of patients with ST-elevation myocardial infarction 1. After the initial shock,
• immediately check for return of organized rhythm and pulse,
• if the patient remains in polymorphic ventricular tachycardia,
• deliver additional shocks at escalating or maximum energy levels as needed. Once the rhythm is stabilized,
• address underlying causes such as electrolyte abnormalities, ischemia, or QT prolongation,
• medications like amiodarone (150 mg IV over 10 minutes, followed by infusion) may be considered after defibrillation to prevent recurrence, as polymorphic ventricular tachycardia can rapidly deteriorate into ventricular fibrillation, and the irregular waveform makes synchronization technically impossible and potentially harmful due to treatment delays, as emphasized in the 2010 American Heart Association guidelines 1.

From the FDA Drug Label

Amiodarone hydrochloride injection is indicated for initiation of treatment and prophylaxis of frequently recurring ventricular fibrillation (VF) and hemodynamically unstable ventricular tachycardia (VT) in patients refractory to other therapy. The treatment for polymorphic ventricular tachycardia (V-tach) with a pulse using cardioversion in unsynchronized mode is not directly addressed in the provided drug label.

• The label mentions hemodynamically unstable ventricular tachycardia (VT), but does not provide information on the use of cardioversion in unsynchronized mode for polymorphic V-tach with a pulse. 2

From the Research

Treatment for Polymorphic Ventricular Tachycardia (V-tach) with a Pulse

The treatment for polymorphic ventricular tachycardia (V-tach) with a pulse is a complex issue, and the approach may vary depending on the specific circumstances.

• The use of cardioversion in unsynchronized mode is generally recommended for unstable ventricular tachycardia, which may be characterized by a change in mental status or loss of consciousness 3.
• However, the treatment of polymorphic ventricular tachycardia (PMVT) is distinct from other forms of ventricular tachycardia, and the principles of triggering and reentry have been demonstrated to govern its initiation and maintenance 4.
• In the case of PMVT, the use of antiarrhythmic medications, such as amiodarone, may be contraindicated in certain situations, and the clinical decision-making requires a distinction between different forms of the arrhythmia 5.
• The role of amiodarone in the management of PMVT can be quite different depending on the specific form of the arrhythmia, and its use may need to be terminated or continued based on the individual case 5.
• In general, the treatment of PMVT requires a practical step-by-step approach for distinguishing these malignant arrhythmias, and medications considered the treatment of choice for one form of PMVT may be contraindicated for another 6.