Performance of a 3.2-mm to 6-mm adaptor.

A study was undertaken to evaluate the performance of a 366-08 adaptor that adapts an in-line bipolar 3.2-mm connector to a 6-mm pulse generator connector. A total of 14 adaptors were implanted in individual patients. Eight of the 14 adaptors failed, an additional failure is probable. The average follow-up time was 32.1 months. The most likely cause of failure was the spring-loaded mechanism of the adaptor, which fatigues with time. All eight of the documented failures presented with loss of capture and were accompanied by increased measured lead impedances. In addition, some failed systems demonstrated loss of sensing. As a result, prophylactic replacement of ventricular lead systems incorporating this adaptor would be advisable. Otherwise, more frequent monitoring with lead impedance measurements may suffice.