Improved extraction of ePTFE and medical adhesive modified defibrillation leads from the coronary sinus and great cardiac vein.
BACKGROUND
Permanent leads with shocking coils for defibrillation therapy are sometimes implanted in the coronary sinus (CS) and great cardiac vein (GCV). These shocking coils, as documented by pathologic examination of animal investigations, often become tightly encapsulated by fibrosis and can be very difficult to remove.


METHODS
One of three configurations of the Guidant model 7109 Perimeter coronary sinus shocking lead was implanted into the distal portion of the GCV of 24 sheep for up to 14 months. Group 1 had unmodified coils (control), group 2 had coils backfilled with medical adhesive (MA), and Group 3 had coils coated with expanded polytetrafluoroethylene (ePTFE). Eighteen leads, three from each group at 6 and 14 months were transvenously extracted from the left jugular vein. The remaining six animals were not subject to extraction. All animals were euthanized for pathological and microscopic examination.


RESULTS
All six of the control, three of the MA, and one of the ePTFE leads required the use of an electrosurgical dissection sheath (EDS) for extraction. Five control, two MA, and none of the ePTFE leads had significant fibrotic attachments to the shocking coils. Significant trauma was observed at necropsy for those leads requiring the use of the EDS for extraction.


CONCLUSIONS
Tissue ingrowth is a major impediment to the removal of defibrillation leads implanted in the CS and GCV of sheep. Reduction of tissue ingrowth by coating the shocking coils with ePTFE or by backfilling with MA facilitates transvenous lead removal with reduced tissue trauma.
Wilkoff
Bruce L
BL
Cleveland Clinic Foundation, Department of Cardiology, Cleveland, OH 44195, USA. wilkofb@ccf.org
Belott
Peter H
PH
Love
Charles J
CJ
Scheiner
Avram
A
Westlund
Randy
R
Rippy
Marian
M
Krishnan
Mohan
M
Norlander
Barry E
BE
Steinhaus
Bruce
B
Emmanuel
Janson
J
Zeller
Peter J
PJ
D000269:Adhesives; D000818:Animals; D020099:Coated Materials, Biocompatible; D003331:Coronary Vessels; D017147:Defibrillators, Implantable; D020878:Device Removal / Q000379:methods*; D004129:Dimethylpolysiloxanes; D004567:Electrodes, Implanted; D011138:Polytetrafluoroethylene; D011474:Prosthesis Design; D012756:Sheep; D012828:Silicones
D000269:Adhesives; D020099:Coated Materials, Biocompatible; D004129:Dimethylpolysiloxanes; D012828:Silicones; C013830:baysilon; D011138:Polytetrafluoroethylene