Bipolar tined polyurethane ventricular lead: a four-year experience.

With the advent of polyurethane as an insulating material for permanent pacemaker leads, concern has arisen over the integrity and long-term durability of polyurethane-insulated pacing leads. Specific concern has arisen over particular bipolar tined polyurethane ventricular leads. We have assessed our 4-year experience with this lead. This experience involves two groups of patients, those with leads manufactured before a certain date and those with leads manufactured at a later date. In the first group (judged to be at increased risk) the failure rate was 8.8%, and in the second group (judged not to be at increased risk) the rate was 3.9%. Lead failure occurred at an average of 17.5 months in the first group. Adequate follow-up on the second group is not available to determine whether or not the failure rate may eventually be as high as that in the early group. Actuarial analysis suggests that survivorship free of lead failure is probably not significantly different in the two groups. This experience points out the need for determining lead failure rates, identifying optimal lead design and configuration, and establishing a lead registry or mechanism by which the integrity of various pacing leads can be evaluated.