Facilitation of transvenous lead extraction using site-specific delivery of electrosurgical energy

Introduction

Excimer laser energy is often required to extract chronically indwelling pacemaker and defibrillator leads from the vasculature and myocardium. This technique can be associated with vascular and right ventricular (RV) injuries. We sought to develop a safer, more effective method by applying site-specific delivery of electrosurgical energy (EE).

Methods

Utilizing a polyacrylamide gel model to simulate soft tissue density, active and passive fixation defibrillator and pacemaker leads were implanted and manually extracted with and without EE delivered to the cathode. The amount of force required for complete removal was measured using a force transducer. The procedure was then repeated in an acute pig model to demonstrate proof of safety. Post mortem gross and histologic specimens were collected from the implantation site.

Results

In the gel model, the force required for extraction, using manual traction in the active (83.7 g) and passive (74.6 g) fixation ICD leads, was reduced by 37.8% and 33.5%, respectively with EE (both p < 0.01). The force required for extraction, using manual traction in the active (85.2 g) and passive (71.9 g) fixation pacemaker leads, was reduced by 64.4% and 42.6%, respectively with EE (both p < 0.01). In an acute implantation pig model using an active fixation lead, delivery of EE to the cathode (n = 6) reduced the force required to manually extract the lead (140 g +/− 32.5 versus 82 g +/− 14.7, p = 0.03). Post mortem analysis of the RV displayed formation of an epicardial hemorrhagic lesion that was also present after manual traction and EE. There was absence of pericardial effusion, perforation, and ventricular arrhythmia.

Conclusions

Site-specific delivery of EE to areas of exposed metal along the lead decreased the force necessary for lead extraction in an in vitro and in vivo model. Further studies are needed to evaluate its application in clinical care.