Incidence and Outcomes of Iatrogenic Complete Atrioventricular Block After Congenital Heart Surgery.

Background: Iatrogenic complete atrioventricular block (ICAVB) has long been noted as a major complication after congenital heart surgery (CHS), and it contributes to complex postoperative care and potentially affects patients' outcomes.

Methods: This study is a retrospective review of the Pediatric Health Information System database from January 1, 2004 to September 30, 2023. All patients who underwent The Society of Thoracic Surgeons benchmark procedures were included. International Classification of Diseases (ICD) 9th and 10th editions were used to identify diagnoses and procedures. All patients with a diagnosis of complete atrioventricular block and placement of a permanent pacemaker after CHS but in the same hospitalization were identified as having ICAVB.

Results: A total of 42,332 patients were identified, with 17,106 (41%) female and 23,042 (55%) non-Hispanic White and with a median age of 5.4 months [interquartile range, 0.4-25.8 months]. Of those patients, 246 (0.6%) had ICAVB. The procedure with the highest incidence of ICAVB was the arterial switch operation with ventricular septal defect (VSD) repair (74 of 1552; 4.5%). On multivariable analysis, the arterial switch operation with VSD repair had the highest adjusted odds of ICAVB (odds ratio, 5.41; 95% CI, 3.57-8.19; P < .001) when compared with isolated VSD repair. A diagnosis of endocarditis was significantly associated with ICAVB. Center volume was not associated with ICAVB. ICAVB was associated with a 121% (95% CI, 98.5%-146.8%) increase in length of stay (P < .001) and increased in-hospital mortality (odds ratio, 2.26; 95% CI, 1.34-3.82; P < .001).

Conclusions: The overall incidence of ICAVB after CHS is low. However, certain procedures have incidences as high as 4.5%. ICAVB is associated with increased postoperative mortality and length of stay. Further work is needed to identify drivers of variation among centers to improve overall outcomes.