OBJECTIVES: This cumulative case study was performed to properly address the 
possible mechanisms, forms, and consequences of "twiddler's," "reel," and 
"ratchet" syndromes.
BACKGROUND: Twiddler's, reel, and ratchet syndromes are rare entities 
responsible for lead displacement of cardiac implantable electronic devices 
(CIED).
METHODS: From 2007 to 2012, 1,472 CIED were implanted at our center. Eighty-nine 
cases were reviewed for failure of pacing circuit integrity. Only 9 met the 
inclusion criteria for idiopathic lead migration (ILM) and were grouped as ILM 
(twiddler) or ILM (reel). For a pooled analysis of cases, a review of the 
literature from 1990 to 2012 was performed, and the authors identified 78 cases 
from 64 publications.
RESULTS: The study population consisted of 87 cases (45 women; median age, 66 
years; 46 with ILM [twiddler] and 41 with ILM [reel]). Migration affected only 1 
lead in 65% of 46 devices with more than 1 lead. None of the previously reported 
risk factors-manual manipulation of the device, elderly age, obesity, oversized 
pocket, and psychiatric history-correlated with the risk of ILM.
CONCLUSIONS: Neither manual manipulation of the device nor the other traditional 
risk factors reported in the literature for ILM syndrome correlated with the 
risk of ILM.