Intraoperative Conduction Mapping to Reduce Postoperative Atrioventricular Block in Complex Congenital Heart Disease

Area of Science:

• Cardiovascular Surgery
• Pediatric Cardiology
• Medical Device Technology

Background:

• Postoperative atrioventricular block requiring pacemaker (AVB/PM) affects 14-25% of complex congenital heart disease (CHD) biventricular repairs.
• Heterotaxy syndrome increases the risk of AVB/PM in these patients.

Purpose of the Study:

• To evaluate the safety and efficacy of intraoperative His bundle (HB) mapping during complex biventricular CHD repair.
• To determine if HB mapping can reduce the incidence of postoperative AVB/PM.

Main Methods:

• Intraoperative HB mapping using a multielectrode grid catheter was performed in 149 patients undergoing complex CHD biventricular repair (2019-2022).
• A cohort of 201 unmapped patients served as controls.
• The primary outcome measured was postoperative AVB/PM.

Main Results:

• HB was identified in 97% of mapped patients; median mapping time was 6 minutes.
• Postoperative AVB/PM was significantly reduced in mapped patients with heterotaxy (2% vs 16%) and those without L-malposed great arteries (3% vs 11%).
• No intraoperative systemic air embolism occurred during HB mapping.

Conclusions:

• Intraoperative HB mapping is safe and effective in reducing postoperative AVB/PM in specific complex CHD populations.
• Patients with heterotaxy syndrome and non-L-malposed great arteries showed significant benefit.
• Further technological advancements are needed for high-risk subgroups.