Myopotential inhibition of demand pacemakers: etiologic, diagnostic, and therapeutic considerations.

Myopotential inhibition of demand pacemakers is a common phenomenon and is responsible for a greater degree of morbidity and possible mortality in patients with pacers. Significant electrical potentials generated by contracting muscle mass gain entry into the pacemaker circuitry causing inhibition of pacemaker activity. Intraoperative and bedside maneuvers can readily precipitate the problem and allow for accurate diagnosis. Holter monitoring frequently can also serve to establish the diagnosis. Pacemaker repositioning, replacement with a bipolar system, use of a fixed-rate pacemaker, and pacemaker "sleeves" are possible intraoperative therapeutic methods. External sensitivity adjustable pacemakers would seemingly allow for noninvasive solutions to the problem.