Subdural to peritoneal shunt is an accepted, but uncommon, treatment for persistent chronic subdural hematomas. Ventriculoperitoneal shunt catheters have been seen to migrate to various unusual locations, including the rectum, vagina and heart1,2. This is an unusual case of a subdural to peritoneal shunt catheter migrating to the thoracic cavity and causing cardiac arrhythmias. We suspect the course of the catheter when placed, either breached or came in contact with the pleura, allowing for erosion over time. The catheter may have been drawn into the thoracic cavity by negative pressure during respiration. It was removed by careful traction at the cranial end without incident.