This is an illustration of pectoral muscle pacemaker inhibition. It is particularly interesting as it shows a maker channel to document what the pacemaker is seeing. This patient was totally dependent on his pacer and was loosing consciousness in spite of his pacemaker. These are two separate strips from the same session. The stars represent paced beats, the diamonds sensed beats, and the diamonds with a cross indicate noise. Note the EKG records the muscle artifact (noisy baseline) and note the sensing of the pectoral muscle and the loss of paced beats as documented in the marker channel. The patient's symptoms stopped with reprogramming the pacemaker.