Physiology General dc0ae1b6 QRS complex is due to: September 2008 A Ventricular repolarization B Atrial depolarization C Conduction through AV node D Ventricular depolarization High-Yield Explanation Ans. D: Ventricular depolarizationQRS complex is due to ventricular depolarization and atrial repolarization. Normal duration is 0.08 sec.