Chronic Performance of Steroid‐Eluting Epicardial Leads in a Growing Pediatric Population:

Abstract

Patient size and congenital heart defects complicate pacemaker therapy in children favoring an initial epicardial approach. Steroid-eluting (SE) epicardial (EPI) leads maintain stable, low pacing thresholds in the short-term when compared to the nonsteroid (NSE) epicardial (EPI) leads. The purpose of this study was to evaluate chronic, 10-year performance of SE leads in growing children compared with NSE EPI leads implanted during the same time interval. From 1990 to 2000, 35 patients (age 1 month to 18 year, median 3 years), 28 with and 7 without congenital heart disease (CHD) received 51 SE leads: 27 ventricular and 24 atrial. NSE leads were implanted in 27 patients (age 1-28 years, median 8 years), 24 with and 3 without CHD: 27 ventricular and 1 atrial. Pacing lead threshold, impedance, and energy were measured at implant and during a 10-year follow-up. Unpaired t-test showed that impedance remained stable for all leads with lower mean values for the SE(376 +/- 55 vs 443 +/- 109 Omega) (P = NS). The mean energy requirement for SE leads at 10 years(1.2 +/- 0.9 microJ)was significantly lower than for NSE(4.4 +/- 5.5 microJ) (P < 0.05). At 2.5-V output, chronic thresholds for SE leads did not significantly differ from implant values for atrial (0.08 vs 0.09 ms) or ventricular (0.08 vs 0.08 ms) sites. There were no differences in SE lead performances among patients with or without CHD. Fracture or dislodgement occurred in two SE (4%) and four NSE (14%) leads. SE outperform NSE EPI leads and show stable, chronic low thresholds over time in all growing children.

Failure of epicardial pacing leads in congenital heart disease: not uncommon and difficult to predict

“…However, in the presence of (relative) contraindications for the transvenous approach, such as small body size, an intra-cardiac shunt or absence of a venous access, an epicardial lead implantation is preferred despite the high rate of lead failure. The estimations of lead longevity vary widely, and seems to be difficult to predict whereas different risk factors for lead failure had been described [3][4][5][6][7][8][9][10]. In our study, we found an incidence of lead failure of 2.3% per lead per year of follow-up.…”

“…Lead failure occurred in 7.4%, with an estimated freedom from lead failure after 5 years of 58% [1]. In another study by Horenstein et al 62 children with a median age of 5.2 years received 79 epicardial leads [10]. During a median follow-up of 6 years a lead fracture occurred in Data are presented as number (percentage) or mean ± standard deviation CHD congenital heart disease; cm centimetres 7.6% of the implanted leads [10].…”

“…In another study by Horenstein et al 62 children with a median age of 5.2 years received 79 epicardial leads [10]. During a median follow-up of 6 years a lead fracture occurred in Data are presented as number (percentage) or mean ± standard deviation CHD congenital heart disease; cm centimetres 7.6% of the implanted leads [10]. Murayama et al found an incidence of lead failure of 3.4% per lead per year of follow-up.…”

Expanding Applications of Defibrillators and Cardiac Resynchronization Therapy to Include Adult Congenital Heart Disease

“…Perhaps a more guided approach such as that suggested by Dekker et al using intra-procedural pressurevolume loop monitoring may have altered the outcome (25). Epicardial pacing systems have been more frequently associated, than transvenous systems, with higher pacing thresholds, diaphragmatic stimulation, lead fracture and insulation breaks (26).The use of steroid eluting leads, does alleviate some of the deterioration in pacing parameters but this unfortunately did not offer an advantage in the second patient (27). Due to previous surgery, the location of viable myocardium for pacing is difficult and www.intechopen.com…”

Surgical Aspects of Cardiac Resynchronisation Therapy

“…However,since the introductionofnewer, steroid-eluting epicardial leads, therehas been asignificant improvement in follow up outcome to an extent that epicardial leads can now be considered similar in performance to transvenous leads (29,30). The steroid tip reduces inflammation at the interface between lead and tissue and has been demonstrated to keep electrical thresholds lower than conventional epicardial leads, both in the short term and long term (31).C ertain epicardiall eads now haves utureless fixation, with asimple screw in mechanism required to position the lead tip (eg: Myodex Epicardial Lead, St Jude Medical, St. paul, Minnesota, USA). An ex-ample of one of these leads can be seen in the postimplantation chest x-ray of Fig.…”