In vitro evaluation of new design lead anchoring sleeves

The purpose of this study was to evaluate various new lead anchoring sleeve designs. These designs were intended to allow coaxial bipolar leads to be tied down and remain securely in position with minimal damage to the lead body, whether tied down with moderate or high tie forces. Axial grooves were made on the outer and/or inner walls of various anchoring sleeve designs. Anchoring sleeves made of extra tear resistant (ETR) platinum catalyzed and peroxide catalyzed (MDX) silicone rubber of various shore, hardness were tested on various Siemens Pacesetter (S-P) and other manufacturers' lead bodies. Tests to slide the sleeves were conducted with the leads in dry and wet conditions, and with and without the Fast-Pass (Siemens Pacesetter, Inc.) coating for lubriciousness. Tie-down deformation of coils was measured from x-ray photos. Mechanical tests and stress calculations were also done to evaluate the mechanical properties of the different lead bodies being tested. The test results showed that compared with existing sleeves, the new design MDX sleeves with axial grooves on the outer wall of the anchoring sleeves provided much lower resultant deformation (62%-84%) on leads when tied down tightly, and exhibited similar sliding forces. Also, it was determined that the MDX anchoring sleeves provided much improved slip forces of two to three times higher than the ETR sleeves. Tie-down damage can also be significantly reduced by strengthening lead bodies. With the protection of the new sleeves, the tie-down damage of S-P leads was the lowest among all the manufacturers' polyurethane or silicone leads tested.(ABSTRACT TRUNCATED AT 250 WORDS)