Origin and Spread of Cardiac Impulse Mnemonic: SAIL MRS. SAVE APPS 1. SA node (generates impulse at highest rate, i.e. 70-80/min) 3 Internodal pathways: 2. AV node Bundle of His 3. Interventricular septum – Left 4. Midportion Right Septal activation Purkinje System 5. Septum (upper to lower) – purkinje system … Continue reading Physiology of Conducting System of Heart