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Updated: May 9, 2026

Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Unusual "ratchet syndrome": spontaneous lead retraction after a generator exchange
Koichiro Ejima1, Morio Shoda, Bun Yashiro
1Department of Cardiology, Tokyo Women's Medical University, 8-1, Kawada-cho, Shinjuku-ku, Tokyo, 162-8666, Japan, koichiro@qf6.so-net.ne.jp.
Abstract:
A 72-year-old female with idiopathic dilated cardiomyopathy underwent a generator exchange for a cardiac resynchronization therapy defibrillator with a full-pocket capsulectomy. The lead position after the operation was identical to that before the operation on the chest X-ray. After 4 months, a subacute exacerbation of her heart failure was caused by cardiac resynchronization therapy failure due to a dislodgement of the left ventricular lead. An aggressive adhesiotomy of the connective tissue around the leads made it possible for the lead to retract by a ratchet-like movement through the suture sleeve, so-called "ratchet syndrome", after the generator exchange.
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