Pacemaker Twiddler syndrome

A 76-year-old woman diagnosed of sick sinus syndrome received in March 2006 a dual-chamber pacemaker with leads placed in the right atrium and right ventricle (arrows, Panel A). The leads were inserted without complications through axillary vein and secured with sutures to the pectoral muscle. A routine pacemaker follow-up performed 3 months later revealed no capture nor sensing of the ventricular lead, even at maximum output, and a considerable increase in the thresholds in the atrial lead. A chest X-ray (Panel B) showed displacement of both leads, especially the ventricle one, retracted and floating in the right atrium (arrows) with windings of the leads around the pulse generator (detail). Electrodes were replaced and the generator fixed to the underlying pectoral muscle. The patient admitted having twisted the pacemaker ‘playing’ with it. Twiddler syndrome, known as the rolling-up of the generator within the pacemaker pocket by the patient intentionally or not, frequently results in leads dislocation, diaphragmatic stimulation, and loss of capture. It is a rare but dangerous cause of lead dislodgement. Patients at risk for this condition include elderly and obese, because their relaxed subcutaneous tissue facilitates the rotation, and mentally handicapped patients. Clinical presentation includes those symptoms related with the failure of the cardiac pacemaker and other symptoms such as abdominal pulsation and stimulation of the pectoral muscle. Limiting the pocket size, suturing the device to the muscle, and the use of a Parsonnet pouch after the first episode may avoid the occurrence of this surprising but potentially fatal complication.