"Twiddling" to the Extreme: Development of Twiddler Syndrome
Twiddler syndrome is an infrequent but potentially dangerous complication of device therapy for dysrhythmias. This syndrome results from the manipulation of the implanted pulse generator by the patient, leading to traction and subsequent lead dislodgement. Originally described by Bayliss as a complication of pacemaker implantation, it has been increasingly reported with implantable cardioverter-defibrillators (ICDs). In this report, we describe a patient with twiddler syndrome in an ICD with substantial retraction of her lead who emphatically denied any manipulation of her device. She underwent revision of her lead with placement of her ICD in a Dacron pouch.

A 65-year-old woman with a history of ischemic dilated cardiomyopathy, a left ventricular ejection fraction of 20%, and nonsustained ventricular tachycardia, underwent an ICD implantation. The ICD was a Marquis VR 7230 CS (Medtronic Inc., Minneapolis, Minnesota) and the lead was a 58 cm Sprint 6947 (Medtronic Inc.). She underwent primary ICD implantation without an electrophysiologic study due to severe left ventricular systolic dysfunction of ischemic etiology. Appropriate sensing, pacing, and defibrillation thresholds were obtained at implantation. A chest x-ray obtained immediately after implantation demonstrated ideal lead position (Figure 1). The patient had no current or history of psychiatric disease. At six-month routine follow-up, the ICD was found to have no capture, even at maximum output. The patient was asymptomatic. At maximum pacing output, repetitive twitching of the left major pectoral muscle was noted with the same frequency of the set pacing rate. A chest x-ray revealed marked retraction of the lead, being withdrawn from the subclavian vein with its tip now positioned over the major pectoral muscle. The patient emphatically denied any manipulation of the ICD. She subsequently underwent explantation of the ICD and its lead. A new Sprint 6947 lead was implanted and tightly secured over its sleeve. The existing ICD was placed in a SynchroMed Dacron mesh pouch (Medtronic Inc.), and its header sutured to underlying muscle for further stability. At five-month follow-up from the second operation, there has been no further "twiddling."


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(A) Posteroanterior chest X-Ray demonstrating appropriate lead placement in the right ventricular apex. (B) Lateral view verifying same.


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Posteroanterior chest X-Ray showing substantial retraction of the lead.

Twiddler syndrome is an uncommon complication of device implantation with a frequency of 0.07–7%. For the most part, it is a painless phenomenon and the majority of patients do not claim a history of manipulating their device. It is more common in the elderly, presumably due to the laxity of their subcutaneous tissues. Other risk factors include obesity, female gender, psychiatric illnesses, and the small size of the implanted device relative to its pocket. Manipulation may cause axial rotation of the pulse generator, twisting, and eventual fracture or dislodgment of the lead. The pulse generator is not usually damaged. For obvious reasons, it can have dangerous consequences. The majority of patients with twiddler syndrome are diagnosed within the first year of implant. Some authorities have advocated the use of a Dacron patch in all cases of device implantation, whereas others have challenged this generalized recommendation. The use of a Dacron patch would stabilize the pulse generator by promoting tissue in-growth. The necessity for careful follow-up, especially in the first few months after surgery, needs to be underscored. The use of a Dacron pouch and adequate fixation of the device header should be strongly considered for patients at risk.