Which of the following results in broad complex tachycardia?: (A) Antidromic conduction in Accessory pathway mediated tachycardia, (B) Ohodromic conduction in accessory pathway mediated tachycardia, (C) AV nodal re-entrant tachycardia, (D) Atrial fibrillation
Answer is A. Antidromic conduction in AP mediated tachycardia results in broad complex tachycardia as the impulses travel in the ventricles inter-myocyte conduction. Speed of conduction of inter-myocyte conduction is less than that of purkinje network leading to broad complex tachycardia. Choices B, C and D result in narrow complex tachycardia. Impoant causes of broad complex tachycardia- Antidromic conduction in WPW Monomorphic VT Torsades de pointes/ Polymorphic Ventricular tachycardia