Comparison of left and right atrial epicardial pacing in patients with congenital heart disease

Epicardial atrial pacing after the extracardiac Fontan operation: Feasibility of an entirely transvenous approach

This series describes an innovative technique for pacing in patients with sinus node dysfunction after extracardiac Fontan surgery. This transpulmonary approach to the left atrial epi-myocardium has been successfully applied to three patients at two centers and resulted in excellent acute and midterm pacing characteristics without known complications. The principal advantage of this procedure in comparison to prior iterations is the absence of pacing material within the pulmonary venous atrium, so that future systemic thromboembolism risk is minimized. The transpulmonary approach for permanent atrial pacing offers a novel solution to the unique challenges for patients after extracardiac Fontan operation.

Lateral thoracotomy for epicardial pacemaker placement in patients with congenital heart disease

OBJECTIVES

Our institution adopted a lateral thoracotomy approach to epicaridal pacemaker implantation with the objective of avoiding epicardial scar tissue and to achieve adequate lead pacing and sensing. We sought to assess the short-term outcomes of this approach.

METHODS

A single-centre review was conducted in paediatric patients and adults with congenital heart disease or inherited arrhythmia syndromes who underwent a lateral thoracotomy for epicardial pacemaker placement from August 2010 to January 2016. Patient histories were recorded along with outcomes including complications, lead and generator performance.

RESULTS

Twenty-one operations were performed in 20 patients (median age 17 years, range 3 months-49 years), including 19 pacemakers and 2 implantable-cardioverter defibrillators (ICDs). Prior epicardial pacemakers had been placed in 11 (55%) patients, including 3 with multiple pacemakers. Most patients had undergone at least 1 prior cardiac operation, with a mean of 3.2 (range 0-7) prior cardiac operations. Through our lateral thoracotomy approach, 17 of the 19 attempted atrial leads (89%) and 20 of the 20 attempted ventricular leads (100%) were successfully implanted with acceptable pacing thresholds. Complications included 1 (5%) bleeding, 2 (10%) pacemaker pocket revisions and 1 late death at 6 months unrelated to the pacemaker. There were no lead failures at a mean follow-up period of 27.5 months (range of 0.7-56.1 months).

CONCLUSIONS

The lateral thoracotomy is a useful approach for epicardial pacemaker implantation in patients with congenital heart disease or inherited arrhythmia syndromes including those with multiple prior operations.

Longitudinal Outcomes of Epicardial and Endocardial Pacemaker Leads in the Adult Fontan Patient

Placement of an epicardial pacemaker system is often preferred over an endocardial system in patients who have undergone a Fontan operation, but data are limited on how these two systems perform over time in patients with Fontan palliation. We performed a retrospective review of adults with Fontan palliation who had pacemaker implantation and interrogation data at Mayo Clinic from 1994 to 2014. Lead parameters, pacing mode, and polarity were collected at the earliest device interrogation report. Clinic notes and device interrogation reports were reviewed at implantation, 6 months, and yearly after implantation to determine impedance, capture threshold (CT), and energy threshold (ET). There were 87 patients with 168 leads in the study cohort. The mean follow-up time was 7.7 years (6 months-19 years). There were 143 epicardial leads (57 atrial and 86 ventricular) and 25 endocardial leads (20 atrial and 5 ventricular). There was no difference in the baseline lead parameters between epicardial and endocardial leads for impedance (610 ± 259 versus 583 ± 156 Ω, p = 0.93), CT (2.0 ± 1.3 versus 1.8 ± 1.3 V, p = 0.28), or ET (7.1 ± 12.5 versus 6.8 ± 18.1 µJ, p = 0.29). Compared to endocardial leads, ventricular epicardial leads were associated with temporal decrease in impedance and increase in ET. Regarding clinical outcomes, epicardial leads had higher rates of failure but similar generator longevity in comparison to endocardial leads. Ventricular epicardial leads were associated with temporal decrease in impedance and increase in ET. Epicardial leads had a higher rate of failure but similar generator longevity compared to endocardial leads.

Cardiac pacing in paediatric patients with congenital heart defects: transvenous or epicardial?

AIMS

Cardiac pacing is a difficult technique in children, particularly in patients with congenital heart defects (CHDs). Few studies to date have addressed this topic.

METHODS AND RESULTS

We performed a retrospective analysis of the results of a single centre. Between 1982 and 2008, 287 patients with CHD, median age of 5 years (25-75%, 1-11) underwent cardiac pacing for sinus node dysfunction (SND) and atrioventricular block (AVB); 97% of patients underwent at least one heart surgery. Endocardial systems (Endo) were implanted in 117 patients, epicardial systems (Epi) in 170, with 595 leads (228 Endo, 367 Epi). Endocardial systems showed a significantly older age group with more frequent SND; Epi a younger age group, with more frequent AVB, greater number of surgical interventions. Perioperative complications were mortality 0.6% (Epi), pericardial effusion 0.6% (Epi), and haemothorax 3.4% (Endo). The median follow-up is 5 (2-10) years: the pacing system failed in 29% of patients, 13% Endo, and 40% Epi (P < 0.0001). Multivariate analysis showed a significantly higher risk of failure for Epi, a lower implant age, greater the number of leads implanted. The risk of malfunction of the leads increases significantly for Epi and the younger age when implanted. The steroid-eluting leads have a lower risk of malfunction (P = 0.05), steroid-eluting Endo leads provide significantly better outcomes than Epi.

CONCLUSION

Cardiac pacing in paediatric patients with CHD shows satisfactory results in the long term. Endocardial systems show significantly better results than Epi systems. A younger age when implanted is a risk factor for complications at follow-up.

Permanent atrial pacing lead implant route after Fontan operation

BACKGROUND

Atrial pacing is indicated for sinus node dysfunction (SND) after Fontan surgery; preferred lead implantation technique is debated. We compare outcomes of transvenous (TV) and epicardial (Epi) atrial lead implants in this population.

METHODS

Retrospective review of Fontan patients undergoing atrial lead implant between 1992 and 2007. Demographics, lead performance data, and outcomes were analyzed.

RESULTS

78 patients had 90 leads implanted: 25 via TV route and 65 via Epi route. Median follow-up was 1.6 years (TV) and 3.6 years (Epi). TV leads were implanted in older patients (23.1 vs 9.3 years, P < 0.001) and at longer intervals after Fontan (15.2 vs 4.9 years, P < 0.001). Pacing indication for most TV leads was SND, while Epi leads were also indicated for atrioventricular block. Acute complication rates were similar (8% TV vs 19% Epi, P = 0.23), but median hospital stay was shorter for TV (2 vs 5 days, P = 0.03). Thrombus was observed in five patients (two in TV; three in Epi), but no thromboembolic events were observed. Mean lead survival was similar (TV 9.9 vs Epi 7.8 years, P = NS). Energy threshold was lower at implant for TV leads (0.9 vs 2.2 microJ, P = 0.049), but similar at follow-up (1.2 vs 2.6 microJ, P = 0.35). Atrial sensing was unchanged over time for TV (2.2 to 2.1 mV, P = NS), but decreased for Epi (3.3 to 2.5 mV, P = 0.02).

CONCLUSIONS

Compared to epicardial leads, transvenous atrial pacing leads may be placed in Fontan patients with lower procedural morbidity and equivalent expectation of lead performance and longevity.

Twenty years of paediatric cardiac pacing: 515 pacemakers and 480 leads implanted in 292 patients

AIMS

The aim of this study was to evaluate long-term outcome of pacemakers (PMs) in paediatric patients.

METHODS AND RESULTS

Patients' data were retrospectively reviewed. We recorded the techniques and systems used, any complication, and outcome. Endocardial leads were inserted by transcutaneous puncture of subclavian vein and fixed with a non-absorbable ligature, and epicardial leads by standard surgical technique. Lead survival was calculated and plotted with the product limit method of Kaplan-Meier. Between 1982 and 2002, 292 patients, aged 8+/-7 years (range 1 day-18 years), underwent PM implantation: the first PM had endocardial leads in 165 patients and epicardial in 127 patients. Structural heart disease (HD) was present in 239 patients. Follow-up was 5+/-4 (range 0.1-18) years. There were no pacing-related deaths. In total, 211 endocardial implantation procedures with 90 atrial and 165 ventricular leads and 145 epicardial procedures with 103 atrial and 123 ventricular leads were performed. Early (<3 months) complications: haemothorax occurred in 3.5% of endocardial leads and dislodgement was not significantly different for atrial and ventricular endocardial leads. Late complications: 63 leads failed (48 epicardial), with the worst outcome for conventional epicardial leads (31 vs. 9% endocardial, P<0.05; steroid eluting 8% epicardial vs. 5% endocardial, P=NS). Endocardial atrial leads failed (7%) in operated HD and ventricular leads failed (6%) after body growth, without difference in estimated mean survival time (11 years). Early and late PM infection/erosion was approximately 2% in all patients.

CONCLUSION

Pacing in children shows good results, but complications are frequent and related to leads. Endocardial pacing showed better long-term outcome.

An alternate technique to pacing in complex congenital heart disease: assessment of the left thoracotomy approach

BACKGROUND

Pacing in children with congenital heart disease often requires alternate approaches to standard transvenous pacing. The surgical approach used to implant the pacemaker leads has been shown to impact lead survival. There is a paucity of pediatric literature describing the experience using a left thoracotomy approach.

OBJECTIVES

To report on short- and mid-term experiences with pacemaker implant via the left thoracotomy approach in children with complex congenital heart disease.

METHODS AND RESULTS

Data were abstracted retrospectively from patients' hospital charts. To date, the left thoracotomy technique has been used in 11 patients with complex heart disease, with a median of three prior cardiac operations. The median patient age was five years (range of two months to 23 years of age). The pacing indications were acquired postoperative atrioventricular block (n=5), sinus node dysfunction (n=5) and long QT syndrome (n=1). There were no intraoperative complications or long-term complications from this approach. The pacing thresholds at implant and follow-up were acceptable in all patients. One patient died in follow-up for reasons unrelated to the pacemaker or arrhythmia.

CONCLUSIONS

The placement of epicardial pacemaker leads via the left thoracotomy approach is a safe and effective alternative to transvenous pacing in pediatric patients with complex congenital heart disease.

Thirty years of experience with epicardial pacing in children

Due to underlying cardiovascular anatomy and size, epicardial pacing may be the preferred method of pacing in small children. To assess long-term safety, we reviewed all epicardial pacemakers implanted in children between 1971 and 2001. We found that 122 patients, with a median age of 5.4 years, had a total of 181 pacemakers and 260 electrodes implanted over a total follow-up of 789 patient-years. Of the total, 12 patients died after the first implantation, with one death attributable to dysfunction of the pacemaker. Reintervention was required in 75 patients after 5.0 +/- 3.2 years, due to depletion of the battery in 45 patients (60%), fracture or dysfunction of electrodes in 27 patients (36%), and infection in 3 patients (4%). In univariate analyses, risk factors for reintervention were an approach via a median sternotomy, with a relative risk of 2.3 (p = 0.0087), and an indication for pacing other than atrioventricular block, with a relative risk of 1.7 (p = 0.0314). In multivariate analyses, the approach via the median sternotomy independently predicted the need for reintervention, with a relative risk of 2.1, and 95% confidence intervals from 1.1 to 4.1 (p = 0.0256). The longevity of the second pacemaker and/or its electrode, assessed in 26 patients, was 3.7 +/- 2.6 years, not shorter than the first implantation (p = 0.4037). We conclude that epicardial pacing is a reliable means of achieving permanent pacing in children, with low morbidity and mortality. A substantial proportion, nonetheless, requires reintervention within five years, warranting meticulous follow-up.

Endocardial Atrial Pacing Lead Implantation and Midterm Follow-Up in Young Patients with Sinus Node Dysfunction After the Fontan Procedure

The purpose of the study was to investigate the results of endocardial lead implantation, lead performance, and follow-up in young patients after the Fontan procedure. A retrospective study was conducted with patients who had endocardial atrial pacing for SND and intact AVN function after Fontan from two pediatric centers. Patient demographics, pacing, and sensing data of endocardial atrial leads were analyzed at the time of pacemaker implantation and follow-up visits. Fifteen patients (weight 42.6 +/- 35 kg) had transvenous endocardial atrial lead implantation at an average age of 11.4 +/- 6.5 years. Active-fixation leads were used in all patients and steroid elution was present in 12 (80%) patients. Adequate P wave sensing was obtained in patients with sinus rhythm (n = 10); the remaining four patients had junctional rhythm without measurable P waves. Lead failure was not observed in any patient during the follow-up period of 2.9 +/- 2.1 years. The energy threshold at implantation was 1.46 +/- 1.5 microJ, 1.54 +/- 0.75 microJ at 3 months, 0.62 +/- 0.45 microJ at 1 year, 0.72 +/- 0.65 microJ at 2 years, 0.75 +/- 0.55 microJ at 3 years, and 0.8 +/- 0.85 microJ at 5 years postimplant. The lead impedance was 648 +/- 298 omega at implantation, 714 +/- 163 omega at 3 months, 744 +/- 195 omega at 1 year, 734 +/- 198 omega at 2 years, 800 +/- 142 omega at 3 years and 830 +/- 200 omega 5 years postimplant. Anticoagulation therapy (aspirin n = 5, warfarin n = 8) was continued by 13 patients. Complications consisted of a pneumothorax at implantation and a transient ischemic attack in one patient 4 years after pacemaker implant. Endocardial atrial leads offer low energy thresholds and can be implanted relatively safely in Fontan patients.

Indications and techniques of pediatric cardiac pacing

There are special challenges associated with the use of transvenous pacemakers in children. For example, a child's chest cavity or vascular dimensions could be too small to host the generator and leads available or required. If leads are implanted, they may stretch as the child grows. This increases the risk that the leads will later dislodge or fracture. Moreover, children requiring pacemakers often have coexisting congenital heart defects and the structural abnormalities of those could hinder easy placement of the pacing system. This article will first review the indications for permanent pacing in children and will then describe the unique challenges associated with such use.

Pediatric pacemaker infections: twenty years of experience

OBJECTIVE

We sought to evaluate possible predictors of early and late pacemaker infections in children.

METHODS

A review was performed of all pacemakers implanted in children at The Children's Hospital of Philadelphia between 1982 and 2001. Infections were classified as superficial cellulitus, deep pacemaker pocket infection necessitating removal, or positive blood culture without an identifiable source.

RESULTS

A total of 385 pacemakers (224 epicardial and 161 endocardial) were implanted in 267 patients at 8.4 +/- 6.2 years. All 2141 outpatient visits were reviewed (median follow-up, 29.4 months; range, 2-232 months). There were 30 (7.8%) pacemaker infections: 19 (4.9%) superficial infections; 9 (2.3%) pocket infections; and 2 (0.5%) isolated positive blood cultures. All superficial infections resolved with intravenous antibiotics. The median time from implantation to infection was 16 days (range, 2 days-5 years). Only 1 deep infection occurred after primary pacemaker implantation. Six patients with deep infections were pacemaker dependent and were successfully managed with intravenous antibiotics, followed by lead-generator removal and implantation of a new pacemaker in a remote location. In univariate analyses trisomy 21 (relative risk, 3.9; P <.01), pacemaker revisions (relative risk, 2.5; P <.01), and single-chamber devices (relative risk, 2.4; P <.05) were identified as predictors of infection. However, in multivariate analyses only trisomy 21 and pacemaker revisions were predictors.

CONCLUSIONS

The incidences of superficial and deep pacemaker infections were 4.9% and 2.3%, respectively. Trisomy 21 and pacemaker revisions were significant risk factors in the development of infection after pacemaker implantation. For primary pacemaker implantation, the risk of infection requiring system removal is low (0.3%).

Epicardial atrial pacemaker lead placement after multiple cardiac operations

We describe a simple technique for the implantation of left atrial epicardial pacing leads in children with congenital heart disease who have undergone multiple operations. The pulmonary veins are exposed to reveal the pulmonary venous to atrial confluence using a left thoracotomy. A pacemaker lead is secured to the posterior left atrium inferior to the lower pulmonary vein. This approach provides a reliable site for atrial lead placement without the need for extensive dissection.

Permanent epicardial pacing in pediatric patients: seventeen years of experience and 1200 outpatient visits

BACKGROUND

The purpose of this study was to evaluate the long-term outcome of all pediatric epicardial pacing leads.

METHODS AND RESULTS

All epicardial leads and 1239 outpatient visits between January 1, 1983, and June 30, 2000, were retrospectively reviewed. Pacing and sensing thresholds were reviewed at implant, at 1 month, and at subsequent 6-month intervals. Lead failure was defined as the need for replacement or abandonment due to pacing or sensing problems, lead fracture, or phrenic/muscle stimulation. A total of 123 patients underwent 207 epicardial lead (60 atrial/147 ventricular, 40% steroid) implantations (median age at implant was 4.1 years [range 1 day to 21 years]). Congenital heart disease was present in 103 (84%) of the patients. Epicardial leads were followed for 29 months (range 1 to 207 months). The 1-, 2-, and 5-year lead survival was 96%, 90%, and 74%, respectively. Compared with conventional epicardial leads, both atrial and ventricular steroid leads had better stimulation thresholds 1 month after implantation; however, only ventricular steroid leads had improved chronic pacing thresholds (at 2 years: for steroid leads, 1.9 muJ [from 0.26 to 16 mu]; for nonsteroid leads, 4.7 muJ [from 0.6 to 25 muJ]; P<0.01). Ventricular sensing was significantly better in steroid leads 1 month after lead implantation (at 2 years: for steroid leads, 8 mV [from 4 to 31 mV]; for nonsteroid leads, 4 mV [from 0.7 to 10 mV]; P<0.01). Neither congenital heart disease, lead implantation with a concomitant cardiac operation, age or weight at implantation, nor the chamber paced was predictive of lead failure.

CONCLUSIONS

Steroid epicardial leads demonstrated relatively stable acute and chronic pacing and sensing thresholds. In this evaluation of >200 epicardial leads, lead survival was good, with steroid-eluting leads demonstrating results similar to those found with historical conventional endocardial leads.

Epicardial pacemaker implantation and follow-up in patients with a single ventricle after the Fontan operation

OBJECTIVES

There is an increasing incidence of sinus node dysfunction after the Fontan procedure. Inability to maintain atrioventricular synchrony after the Fontan operation has been associated with an adverse late outcome. Although pacing may be helpful as a primary or adjunct modality after the Fontan procedure, the effects of performing a late thoracotomy or sternotomy for epicardial pacemaker implantation are unknown. In addition, little is known about the long-term effectiveness of epicardial leads in patients with single ventricles. The purpose of this study was to compare the hospital course and follow-up of epicardial pacing lead implantation in patients with Fontan physiology and patients with 2-ventricle physiology.

METHODS

We retrospectively reviewed all isolated epicardial pacemaker implantations and outpatient evaluations performed between January 1983 and June 2000.

RESULTS

There was no difference in the perioperative course for the 31 Fontan patients (27 atrial and 41 ventricular leads [68 total]) compared with the 56 non-Fontan subjects (9 atrial and 61 ventricular leads [70 total]). The median length of stay in Fontan and non-Fontan patients was 3 and 4 days, respectively. There was no early mortality in either group. Pleural drainage for 5 days or longer was reported in 4% of the Fontan cohort and 3% of the non-Fontan group. Late pleural effusions were identified in only 2 patients in the Fontan group and 2 patients in the non-Fontan group. There was no significant difference in epicardial lead survival between the Fontan group and the non-Fontan group (1 year, 96%; 2 years, 90%; 5 years, 70%). The overall incidence of lead failure was 17% (24/138).

CONCLUSIONS

Epicardial leads can be safely placed in Fontan patients at no additional risk compared to patients with biventricular physiology. Sensing and pacing qualities were relatively constant in both the Fontan and non-Fontan groups over the first 2 years after implantation.