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Updated: Oct 19, 2025

Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
Double Twist
Wei-Chieh Lee1,2, Yung-Lung Chen2
1Institute of Clinical Medicine, College of Medicine, National Cheng Kung University.
Abstract:
A rare complication about "Twiddler syndrome" is reported, and an interesting image about "double twist" is presented. A 78-year-old woman received a single-chamber implantable cardioverter defibrillator (ICD) for secondary prevention of ventricular arrhythmia. After she played mahjong (a traditional Chinese board game) overnight, her ICD lead sense amplitude decreased suddenly and did not recover. The intracardiac electrogram of ICD also found ventricular lead noise before this episode. Chest radiography revealed a twisted lead at the ICD pocket and a twisted and retracted ICD lead in the right atrium. An old ICD lead could not be straightened and removed, and a new ICD lead was implanted at the right ventricle. Anti-coagulation was used to prevent thrombosis for the old ICD lead.
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