For polymorphic VT (Torsades), which treatment is recommended initially?

For polymorphic VT (Torsades), which treatment is recommended initially?

• A. Amiodarone and defibrillation
• B. Lidocaine and pacing
• C. Adenosine and synchronized cardioversion
• D. Magnesium sulfate and defibrillation

Answer: (D)

Polymorphic VT due to torsades de pointes is driven by QT prolongation, so the initial treatment focuses on correcting that mechanism. Intravenous magnesium sulfate is used first because magnesium stabilizes the cardiac membranes and suppresses the early afterdepolarizations that trigger torsades, even if magnesium levels are normal. Give a bolus (typically 1–2 g IV) and infuse as needed. If the patient is pulseless or severely unstable, proceed immediately to defibrillation. Other options like amiodarone, lidocaine, or adenosine don’t address the underlying QT-related trigger and aren’t the preferred initial therapy for torsades.

Polymorphic VT due to torsades de pointes is driven by QT prolongation, so the initial treatment focuses on correcting that mechanism. Intravenous magnesium sulfate is used first because magnesium stabilizes the cardiac membranes and suppresses the early afterdepolarizations that trigger torsades, even if magnesium levels are normal. Give a bolus (typically 1–2 g IV) and infuse as needed. If the patient is pulseless or severely unstable, proceed immediately to defibrillation. Other options like amiodarone, lidocaine, or adenosine don’t address the underlying QT-related trigger and aren’t the preferred initial therapy for torsades.