Background
The first implantable pacemaker was placed in the 1958, ushering in a new frontier of cardiovascular medicine. Since that time, implantation of cardiovascular implantable electronic devices (CIED) has exploded. The growth in CIED implants has been accompanied by a similar growth in the need to remove them. With the development of specialized tools and advancement of our understanding of transvenous lead extraction (TLE), success rates are excellent, typically reported around 98%. There are, however, challenges. Over time an ingrowth of fibrous tissue binds the leads of these devices to surrounding vascular and cardiac structures and to other leads. This tissue creates most of the challenges faced during transvenous lead extraction. The spectrum of ingrowth and adhesion of the leads is quite variable, and we have a long way to go in our understanding of how to predict these adhesions.
Multiple modalities have been shown to be effective in detecting adherence between the leads and other structures. CT, transesophageal echo (TLE), intravascular ultrasound (IVUS), and intracardiac echo (ICE) have all be studied. Patel et al detected some degree of adherence in 86% of subjects and severe adherence with the lead outside the contrast lumen in 19%1 In another study evaluating CT in TLE, Svenberg et al reported severe lead adhesion in about 45% of subjects.2 TEE has also been evaluated to detect adherence to the SVC and cardiac structures. Nowosielecka reported binding to the SVC and right heart structures in 34% of patients.3 IVUS and ICE may also be used to assess lead binding to cardiac and venous structures. Using IVUS, Beaser et al reported high grade adherence in 25% of patients.4Sadek et al used ICE to look for lead binding to the SVC or myocardium and detected significant binding in 36% of patients.5 While, the modalities differ in how they detect these adhesions and, to some degree, the structures being assessed, together, the studies tell us that adhesions binding leads to other structures is common.