A-H interval on ECG is for conduction -: (A) Through His-Purkinje system, (B) From AV node to bundle of His, (C) From Purkinje system to ventricular fibres, (D) Through ventricular fibers
Answer is B. Ans. is 'b' i.e., From AV node to bundle of Hiso Certain intervals are measured to provide information regarding AV block.PA interval: It is time taken from onset of P-wave to onset of deflection in atrial catheter. It is an index of intra-atrial conduction. Normal vlaue is less than 55 mS.AH interval : it represents conduction through AV node, i.e., conduction from AV node to bundle of His. Normal vlaue is less than 130 mS.HV interval : It represents conduction through His-Purkinje system, i.e., conduction from His-Purkinje system to ventricular muscle fibers. Normal value is less than 50 mS.