Impact of permanent pacemaker for iatrogenic atrioventricular block on outcomes after congenital heart surgery.

ABSTRACT

OBJECTIVE: The need for permanent pacemaker (PPM) for iatrogenic atrioventricular block (AVB) after congenital heart surgery is about 1%. We aim to evaluate the long-term outcomes of patients with PPM for iatrogenic AVB and compare them to patients with an optimal repair (trivial/no residua)- Residual Lesion Score (RLS) Class-1 repair without PPM need. METHODS: We reviewed 183 patients discharged with PPM for iatrogenic AVB from 2011 to 2022. Patients who survived to discharge with >30 days of follow-up were matched 11 with a cohort of RLS Class-1 patients based on fundamental diagnosis and primary procedure. RESULTS: Median age at PPM placement was 1.4 years (IQR 4.3 months - 3.9 years). The cumulative incidence of moderate or greater ventricular dysfunction at 1 year and 5 years was 11% and 18% in PPM patients, respectively, compared to 3% and 7% in RLS Class-1 patients (subdistribution HR, 2.6; 95% CI, 1.2-6.1; P =0.022). Independently, PPM patients with hypoplastic left heart syndrome (P =0.027) and who had undergone STAT Mortality Category 5 procedures (P =0.033) were at higher risk of ventricular dysfunction. Transplant-free survival at 1 year and 5 years was 94% and 89% in PPM patients, respectively, compared to 98% and 97% in RLS Class-1 patients (P =0.044). Additionally, PPM patients with palliated circulation had significantly lower transplant-free survival (P <0.001). CONCLUSIONS: Compared to patients with an optimal repair without PPM, patients with PPM for iatrogenic AVB are at higher risk of developing moderate or greater ventricular dysfunction and have lower transplant-free survival.