Ten-Year Clinical Experience with the Lumenless, Catheter-Delivered, 4.1-Fr Diameter Pacing Lead in Patients with and without Congenital Heart

Background: Patients with congenital heart defects (CHD) often present more challenges to pacing therapy due to anatomy than those without CHD. The lumenless, 4.1Fr diameter M3830 pacing lead (Medtronic, Inc., Minneapolis, MN, USA), approved for use in 2005, has, to date, reported to have excellent short-term (<6 years) lead performance. Unfortunately, very long-term performance is unknown, especially among CHD patients and with implants at alternate pacing (AP) sites. This study reports a 10-year clinical experience with the M3830 lead. Methods: Records of patients who received the M3830 lead were reviewed: patient demographics, implant techniques and locations, sensing and pacing characteristics, impedances (Imp), and any complications at implant and follow-up. Results: From 2005 to 2015, 141 patients (ages 2–50, mean 20.1 years, 57% males) received 212 leads: atrial 115; ventricle 97. CHD was present in 62% of patients. Leads were inserted at AP sites in 96% of patients. Postimplant follow-up was from 3 months to 10 years (mean 56.3 months). Comparative implant versus follow-up values (mean ± standard deviation) were available on 196 leads (92.5%), showing persistently low (<1 v @ 0.4–0.5 ms) pacing thresholds (P = 0.57). Sensing was also comparable (atrial leads, P = 0.41; ventricular leads, P = 0.9). Impedances differed (P < 0.05) but remained within the normal range. Two A leads became dislodged and one was repositioned while two other leads (1 A, 1 V) were extracted. There are no differences observed in the pacing characteristics between the CHD and non-CHD groups on follow-up. Conclusions: The 4.1Fr lumenless pacing lead shows ease of implant regardless of CHD or AP site, excellent very long-term (10 years) stability, and performance indices with a very low rate of complications.