A-48 year old presents with history of precordial chest pain. He has BP of 80/60 mm of Hg. EKG shows wide QRS complex with no preceding P waves and a rate of 112/min. The most immediate step in the management of this patient would be
Intravenous lignocaine
DC electrical cardioversion
Overdrive atrial pacing
Primary percutaneous transluminal angioplasty