Decellularized Allografts for Right Ventricular Outflow Tract Reconstruction in Children

Objective: Determine the midterm outcomes of decellularized allografts for right ventricular outflow tract (RVOT) reconstruction in children less than 12 years of age. Methods: The study included all consecutive patients submitted to RVOT reconstruction with decellularized allografts between June 2006 and June 2016. Besides clinical and echocardiographic control, 20 patients with more than five years of follow-up were evaluated with computed tomography (CT) scans to determine allograft diameters and calcium scores. Structural valve deterioration was defined as any peak gradient above 40 mm Hg and/or insufficiency of moderate or severe degree. Conduit failure was defined as the need for allograft reintervention. Results: There were 59 patients with a median age of six years (range = 0.01-12 years). The most common operation was the Ross procedure (34%). Mean clinical follow-up was 5.4 (2.8) years and was 94% complete. At eight years, only two patients needed a reintervention, with a 90.9% freedom from this event. Structural valve deterioration occurred in 13 patients, 5 due to stenosis and 8 due to insufficiency, with a freedom from structural valve deterioration due to any cause of 64.9% at eight years. Late CT scans demonstrated the absence or minimal calcification of the conduits. Conclusions: Decellularized allografts for RVOT reconstruction in children were associated with a low incidence of structural valve deterioration and conduit failure. Although these results still need to be confirmed in larger series and with longer follow-up, our data suggest favorable outcomes, at least in the first decade after the operation.