Epicardial Lead Performance Trends in Pediatric and Congenital Heart Disease.

Background: Epicardial pacing systems, rather than transvenous systems, are utilized in pediatric patients who are too small to undergo transvenous access and/or have complex congenital heart disease (CHD) anatomically precluding a transvenous system. Longitudinal performance studies indicate that epicardial leads have higher failure rates when compared with transvenous leads but there are limited data on lead measurement changes in the acute phase after implantation. The objective of this study was to assess epicardial lead performance in the acute postimplant period and at one-year follow-up. Methods: This is a retrospective single center study of children and adult patients with CHD undergoing epicardial bipolar pacing lead and generator implantation between January 2012 and June 2022. We empirically selected 2 V as a critical lead threshold. Results: There were 256 leads implanted in 127 patients (mean age 6.1 ± 9.8 years), including 201/256 (79%) leads in patients with CHD. At the time of implant, 47/256 leads (18%) had a lead threshold of ≥2 V. Of those, 42 of 47 (89%) had recorded threshold values on postoperative day 1 (POD1) and 37 of 42 (88%) had decreased to a more acceptable threshold that was <2 V. For patients with an implant threshold of ≥2 V; impedance >1000 ohms, presence of CHD, perioperative or acute postop status, and location of the lead (atrial vs ventricular) did not significantly impact the odds of having a persistently high threshold (≥2 V) on POD1. Conclusion: Epicardial pacing lead thresholds generally improve in the immediate postop period and in our experience most leads with a high implant threshold improved to <2 V by POD1.