Phrenic Nerve Stimulation in a Patient with a Dorsal Column Stimulator

We present a case of a 76-year-old female who developed recurrent left-sided muscle spasms resembling hiccups after permanent dorsal column stimulator (DCS) implantation. The patient had a cardiac resynchronization device with defibrillating capabilities (CRT-D) in place, which was interrogated before and after the permanent DCS placement with no interference reported. Due to the timing of the event with the placement of the DCS, it was presumed that the spasms were related to the DCS implantation, and removal of the DCS was considered. However, further evaluation by a cardiology consultant revealed that a lead from her CRT-D was most likely stimulating the phrenic nerve and causing diaphragmatic contractions. The patient was sent to the electrophysiology clinic where the voltage on her left ventricular lead was reduced, and her symptoms resolved completely. Due to the time, risks, and expense of implanting a DCS, it is imperative to consider all other possible causes of diaphragmatic contractions prior to removing a DCS system.