<prompt> Sudden death can be due toVentricular fibrillationQT prolongationAtrial flutterVPCs  <response>: Ans. a Ventricular fibrillation. Ref. Harrison, Principles of Medicine, 18thChapter 233. Most common electrical mechanism of true cardiac arrest is ventricular fibrillation, responsible for 65-80 of cardiac arrests. Episodes of cardiac arrest during Holter monitoring reveal that 34th of sudden deaths are due to VTVF. Treatment: Imparted cardioversiondefibrillatoramiodarone.VPCs in asymptomatic Young individual need no treatment. 