Loss of Ventricular Function After Bidirectional Cavopulmonary Connection: Who Is at Risk?

Decline of single ventricle systolic function after bidirectional cavopulmonary connection (BDCPC) is thought to be a transient phenomenon. We analyzed ventricular function after BDCPC according to ventricular morphology and correlated this evolution to long-term prognosis. A review from Mayo Clinic databases was performed. Visually estimated ejection fraction (EF) was reported from pre-BDCPC to pre-Fontan procedure. The last cardiovascular update was collected to assess long-term prognosis. A freedom from major cardiac event survival curve and a risk factor analysis were performed. 92 patients were included; 52 had left ventricle (LV) morphology and 40 had right ventricle (RV) morphology (28/40 had hypoplastic left heart syndrome (HLHS)). There were no significant differences in groups regarding BDCPC procedure or immediate post-operative outcome. EF showed a significant and relevant decrease from baseline to discharge in the HLHS group: 59 ± 4% to 49 ± 7% or - 9% (p < 0.01) vs. 58 ± 3% to 54 ± 6% or - 4% in the non-HLHS RV group (p = 0.04) and 61 ± 4% to 60 ± 4% or - 1% in the LV group (p = 0.14). Long-term recovery was the least in the HLHS group: EF prior to Fontan 54 ± 2% vs. 56 ± 6% and 60 ± 4%, respectively (p < 0.01). With a median follow-up of 8 years post-BDCPC, six patients had Fontan circulation failure, four died, and three had heart transplantation. EF less than 50% at hospital discharge after BDCPC was strongly correlated to these major cardiac events (HR 3.89; 95% Cl 1.04-14.52). Patients with HLHS are at great risk of ventricular dysfunction after BDCPC. This is not a transient phenomenon and contributes to worse prognosis.