Spontaneous rotation of permanent pacemaker--a cause of muscle stimulation and myopotential inhibition

In 5 of 192 patients who received their first pacemaker during a 17-month period, severe pectoral muscle stimulation was caused by spontaneous rotation of the pacemaker in the pocket, so that the uncoated side faced backwards. All five patients were women with abundant, loose subcutaneous tissue which allowed increased mobility of the pacemaker. This causal mechanism of muscle stimulation seems to be related to the reduced size and the coating of modern pacemakers. Reprogramming of the pacemaker to a lower output solved the problem in three cases, but reoperation was necessary in two. These cases stress the need to secure the pacemaker to the fascia during implantation, particularly in patients at enhanced risk. For such patients, use of a pacemaker equipped with suture holes may be advisable.