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Updated: Jul 8, 2026

A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation
Published on: February 28, 2012
Twiddler's syndrome in a patient with a biventricular-defibrillator device
Faizel Osman1, Ross Ward, Adrian Morley-Davies
1Department of Cardiology, City General Hospital, University Hospital of North Staffordshire NHS Trust, Newcastle Road, Stoke on Trent ST4 6QG, UK. f.osman@bham.ac.uk
Abstract:
A 69-year-old man with previous myocardial infarction and proximal three-vessel coronary artery disease underwent coronary bypass grafting, with an epicardial lead placed on the lateral left ventricular wall during surgery. A cardiac resynchronization therapy-defibrillator (CRT-D) device was subsequently implanted using active right atrial and right ventricular leads, with the pulse generator placed in a pre-pectoral pocket. Four weeks later, the right atrial lead was failing to sense or capture, and chest X-ray revealed it had pulled out of the myocardium and coiled up behind the device; a diagnosis of Twiddler's syndrome was made. Twiddler's syndrome is unusual in patients with CRT-D devices and may cause symptoms such as inappropriate shocks and hiccups. Placement of the pulse generator in a sub-pectoral position may help prevent it.
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