McGill Case 349

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 348 | Next Case: McGill Case 350

Myopotential Inhibition of VDD pacemaker in unipolar mode This is a classic recording of myopotential inhibition of a pacemaker. Note the pacemaker that was following the patient's p waves for the first three beats, stops pacing as soon as the baseline records the "buzz" of the pectoral muscle activity. As the pacer stops pacing, the patient's underlying rhythm is seen which appears to be 2:1 Av block. As the "buzz" disappears normal pacing returns.