This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: ECG and Arrhythmias 1, Subject name: Medicine
A 30 year old female presented with eclampsia. After 3 hours of admission she is complaining of palpitations for which ECG was performed. Vitals are stable. What is the next best management? 
Select and explain. 
A. DC shock, B. MgSO4, C. Amiodarone, D. Adenosine
B: MgSO4
Answer: B: MgSO4 
Explanation: Vitals are stable.ECG of patient shows: Broad QRS Complex tachycardia (QRS > 160msec) . HR [?] 300/min Amplitude of every QRS is variable. Dx: Torsades de pointes --> Type of Polymorphic ventricular tachycardia --> due to prolongation of QT Trigger -Vomiting, hypokalemia. Tachyarrhythmia management: In unstable patient --> Cardioversion In stable patient --> Mg SO4. -Amiodarone: monomorphic VT -Adenosine: AVN