Cano Ó, Dandamudi G, Schaller RD, Pérez-Roselló V, Ayala HD, Izquierdo M, Osca J, Sancho-Tello MJ, Rueda J, Ruiz E, Insa B, Martínez-Dolz L, Vijayaraman P.J Cardiovasc Electrophysiol. 2021 Oct;32(10):2692-2703. doi: 10.1111/jce.15213. Epub 2021 Aug 26.PMID: 34405485
Take Home Points:
- This was a four center study involving 20 patients with diverse forms of congenital heart disease undergoing conduction system pacing
- The most common diagnosis was CCTGA followed by tetralogy of Fallot and the majority (70%) of patients had a prior VSD patch as part of the operative repair
- Excellent results in terms of QRS morphology and pacing electrical parameters were achieved at implant and were stable at 1 year post implant
- This preliminary experience suggests the safety and feasibility of conduction system pacing among adults with congenital heart disease
Commentary by Dr. Jeremy Moore (Los Angeles) Congenital and Pediatric Cardiac EP section editor:
Patients with congenital heart disease are uniquely susceptible to pacing induced cardiomyopathy and dyssynchrony. To date, retrospective studies have demonstrated that conventional CRT is beneficial for this patients, however frequent anatomical and technical challenges limit CRT application in many forms of congenital heart lesions. More recently, conduction system pacing (CSP, primary in the form of His bundle pacing [HBP]) has been applied to patients with congenitally corrected transposition (CCTG) with excellent preliminary results, but is understudied among other forms of congenital heart disease.
This multicenter retrospective study evaluated the safety and feasibility of conduction system pacing (CSP) among a diverse group of patients with congenital heart disease at 4 centers. The most common diagnosis was CCTGA (n=6) as has been reported previously, all of whom underwent His bundle pacing (HBP) except one that underwent left ventricular septal pacing (LVSP). The next most common diagnosis was TOF (n=4) with HBP in 2, LBBP in 1 and LVSP in 1. Of note, a further 3 patients carried the diagnosis of AV canal defect which is uniquely associated with an inferiorly displaced conduction system. Pacing locations were variable in this group, with one HBP, LBBP and LVSP each. Finally, 2 patients had undergone prior Senning operation, where lead placement targeted the subpulmonic LV, both with LBBP. In the group overall, 14 patients had a prior VSD patch placement as part of prior cardiac operations, in whom the following pacing locations were utilized: LBBP in 5, HBP in 5 and LVSP in 4.
Although the implant procedures were noted to be challenging in some, the results were excellent with a decrease in the mean QRS duration from 144 to 116 ms (p=0.001) and low pacing thresholds that remained stable at a median follow up of 1.3 years. There was one lead failure in a Senning patient that was replaced safely 1 week post implant.
This present work evaluated the safety and feasibility of CSP in a diverse cohort of patients with congenital heart disease. This early study demonstrates that these features can be achieved, albeit in a small cohort with limited follow up. CSP in congenital heart disease appears to represent and underutilized strategy for cardiac resynchronization. Further study is warranted to understand the long-term outcomes and unique challenges of CSP in congenital heart disease.