Twiddler's Syndrome

• Rare occurrence
• Shape and weight of pacemakers today
• Subconscious, inadvertent or deliberate rotation of pacemaker in its subcutaneous pocket
• Older women may be at particular risk
• Loose subcutaneous tissue
• Lead retracts and begins to wrap around the pacemaker itself
• Dislodging lead from endocardium and causing
• Malfunction of device
• Pacemaker may begin to stimulate diaphragm, vagus or phrenic nerve, pectoral muscles or brachial plexus
• Imaging findings
• Chest x-ray shows looping of wires around pacer
• Retraction and change in position of tip if wire or catheter
• May result in sudden cardiac arrest due to conduction disturbances
• Also occurs with automatic implantable cardiac defibrillators (AICDs)

 
Twiddler's Syndrome: Frontal chest radiograph in top photo demonstrates pacemaker lead extending into right ventricle (blue arrows); bottom photo, one year later, shows wire lead is wound around pacer and tip of ventricular lead has retracted into the left subclavian vein (red circle)