McGill Case 54

This case report is kindly provided by Michael Rosengarten from McGill and is part of the McGill Cases. These cases come from the McGill EKG World Encyclopedia. Previous Case: McGill Case 53 | Next Case: McGill Case 55

This is a recording with five surface leads ( I, II, AVF, V1 and V6), and 6 intracardiac leads the high right atrium (RA), the proximal to distal coronary sinus (CS prox to CS Dist). Note the depolarization of the atria starts from the RA and then to the proximal CS and lastly to the distal CS. Also note the ventricular potentials seen on the CS tracings.