Unexpected cause of involuntary muscle movements: Reel syndrome.

Reel syndrome is an uncommon condition in which a pacemaker malfunctions owing to transverse rotation of the pulse generator and resultant lead displacement. In this case report, we present a patient complaining about reflex involuntary left upper extremity jerks, which is consistent with Reel syndrome. As the number of implantable devices increases in the population, cardiologists should be aware of this complication.