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.
This EKG shows a nodal escape rhythm. Note the lack of P or P' waves. Often the P' wave is hidden in the QRS as the nodal escape conducts down to the ventricle and up to the atrium in a fashion such that the QRS and P' wave occur simultaneously.
