(P075) OUTCOMES AFTER PEDIATRIC PULMONARY VALVE REPLACEMENT IN PATIENTS WITH TETRALOGY OF FALLOT

Background: People with tetralogy of Fallot (TOF) may require a transannular patch during primary repair, which leads to pulmonary valve regurgitation. Pulmonary valve replacement (PVR) is performed to prevent complication of chronic pulmonary regurgitation, but the optimal timing of PVR remains a matter of debate. This study aimed at assessing the association of PVRs performed < 18 years of age on the rate of hospitalizations, interventions, and mortality.

METHODS AND RESULTS: This is a retrospective observational cohort of people with TOF born in Québec between 1982 and 2015, combining clinical and administrative data. Marginal means/rates models and survival curves were used to compare outcomes between patients with pediatric PVR ( < 18 years) and those without. Outcomes of interest were rates of cardiac hospitalizations, all-cause hospitalizations, cardiac interventions, and mortality. Groups were balanced using models weighed on the inverse probability of receiving pediatric PVR.

Of the 316 eligible patients, 58 (18.4%) received a pediatric PVR. As depicted in Figure 1, the cumulative incidence of PVR before the age of 18 was 21.2% (95% CI: 16.5%-27.2%). There were 59 additional patients who underwent a first PVR after 18 years old for a cumulative incidence of PVR at 30 years of 50.2% (95% CI: 45.0%-58.2%). Figure 2 shows the outcomes of pediatric PVR. Compared to patients not receiving pediatric PVR, those receiving a pediatric PVR were at increased risk of cardiac hospitalizations, although the rates of cardiac hospitalization were low: 0.50 versus 0.09 hospitalizations per 20 years [Hazard ratio (HR)=4.71 (95%CI 2.22-9.96)]. Patients receiving a pediatric PVR had a comparable risk of all-cause hospitalizations [HR=0.95 (95%CI 0.71-1.26)] and of cardiac interventions [HR=1.13 (95%CI 0.72-1.77)]. Among patients with pediatric PVR, 4/58 (6.9%) underwent redo-PVR, compared to 3/59 (5.1%) for those who received a first PVR after 18 years of age. At 10 years post-PVR, freedom from redo-PVR was 87.4% (95% CI: 59.8%-96.5%) for pediatric PVR and 93.8% (95% CI: 78.4%-98.4%) for adult PVR. Mortality was rare with 2/58 (3.4%) death in patients with early PVR, and 9/258 (3.5%) death in patients without.

Conclusion: Patients who underwent pediatric PVR had higher rates of cardiac hospitalizations, but similar rates of all-cause hospitalizations, cardiac procedures, redo-PVR, and mortality. In this observational cohort, pediatric PVR was not associated with an improved outcome.