Key result
Intraoperative His bundle mapping is linked to ~88% less postoperative AVB/PM in heterotaxy patients.
Why the study?
Postoperative atrioventricular block requiring a pacemaker complicates 14% to 25% of biventricular repairs for complex congenital heart disease and heterotaxy syndrome, prompting evaluation of whether intraoperative His bundle mapping is safe and reduces this complication.
Cohort (n=350)
Answers are grounded in this paper and cite their sources.
Captured external expert commentary on this paper, strongest first. Original sources are linked where available.
“It's incredibly gratifying we were able to show that this does make a difference. Cardiologists get involved at the outset to prevent heart block and pacemakers from happening—and then the cardiac surgeons can make these amazing repairs.”
“There are certain high-risk patients who are mapped but are still developing heart block at the same rate as those without mapping, so more needs to be done to help them. But the data show we've identified several groups of conditions where there was a meaningful reduction in heart block and a need for a permanent pacemaker. Those patients can benefit from mapping.”
“But with mapping, you can reduce heart block down to about 10%, and that makes a big difference. It means we can move forward on ventricular septation with confidence. Many children who have the procedure are doing quite well and have been able to avoid the Fontan, which is a goal.”
Clinical investigation demonstrates intraoperative conduction mapping reduces atrioventricular block in complex congenital heart disease, suggesting enhanced surgical precision.
BACKGROUND Postoperative atrioventricular block requiring pacemaker (AVB/PM) complicates 14% to 25% of biventricular repair operations for complex congenital heart disease (CHD) and in those with heterotaxy syndrome. OBJECTIVES This study aimed to evaluate if intraoperative His bundle (HB) mapping during complex biventricular CHD repair can be performed safely and reduce postoperative AVB/PM. METHODS HB mapping was performed using a commercially available multielectrode grid catheter in patients with complex CHD undergoing biventricular repair between 2019 and 2022 compared with an unmapped cohort. The primary outcome was postoperative AVB/PM. RESULTS One hundred forty-nine patients underwent HB mapping compared to 201 unmapped controls. The median age of mapped patients was 1.9 years (Q1-Q3: 0.9-3.9 years). Heterotaxy syndrome was present in 31% (n = 46 of 149), ventricular septal defect in 95% (n = 142 of 149), and prior single ventricle palliation in 68% (n = 89 of 149). The HB was identified in 97% (n = 144 of 149) of cases. The median mapping time was 6 minutes. No episodes of intraoperative systemic air embolism occurred. Postoperative AVB/PM frequency was significantly reduced in mapped patients with heterotaxy (2% [n = 1 of 46] vs 16% [n = 11 of 67]; P = 0.026) and in patients without L-malposed great arteries (3% [n = 3 of 88] vs 11% [n = 15 of 134]; P = 0.045). CONCLUSIONS Intraoperative HB mapping can be performed safely and is associated with significantly reduced postoperative AVB/PM in select populations undergoing complex biventricular repair, including heterotaxy syndrome and non-L-malposed great arteries. Nonetheless, certain subgroups remain at risk for AVB/PM, showing the need for further improvements to current intraoperative HB mapping technology and techniques.
No takes yet. Share an insight, caveat, or question.
O’Leary et al. (2024) conducted a cohort in Complex congenital heart disease (n=350). Intraoperative His bundle (HB) mapping vs. Unmapped cohort was evaluated on Postoperative atrioventricular block requiring pacemaker (AVB/PM). Intraoperative His bundle mapping significantly reduced postoperative AVB/PM in patients with heterotaxy (2% vs 16%; P=0.026) and without L-malposed great arteries (3% vs 11%; P=0.045).
Synapse has enriched 10 related papers. Consider them for comparative context: