McGill Case 347

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 346 | Next Case: McGill Case 348

The Holter system has added markers where it detected pacemaker spikes. The yellow arrow indicates the detection of a ventricular spike and the blue arrow an atrial spike. The recording shows pectoral muscle inhabition of the pacemaker (turquoise arrow). It is characteristic to see muscle artifact on the recording as seen here ( mostly between the two red arrows) Note there is no detection of a ventricular pacing spike, and also there is no native QRS to be sensed! This is a form of inappropriate sensing.