The Fate of Homograft Versus Polytetrafluoroethylene Conduits After Neonatal Truncus Arteriosus Repair

Abstract

Background: Despite significant improvement in outcomes with truncus arteriosus (TA) repair, right ventricular outflow tract (RVOT) reconstruction with a right ventricular to pulmonary artery (RV-to-PA) conduit remains a source of long-term reintervention and reoperation. This study evaluated our experience with reintervention in homograft and polytetrafluoroethylene (PTFE) RV-to-PA conduits in neonates. Methods: Primary TA repairs from 2004 to 2016 at a single institution were included. Stratification was based on RVOT reconstruction with PTFE or homograft conduit. Primary outcome was operative conduit replacement. Secondary outcomes included the rates and types of catheter-based conduit interventions. Results: Twenty-eight patients underwent primary TA repair and 89.3% (n = 25) of them had RVOT reconstruction with a homograft (28.0%, n = 7) or PTFE (72.0%, n = 18) conduit. Rates of reoperation for conduit replacement and catheter-based interventions were similar between those with PTFE and homograft conduits (85.7% vs 72.2%, P = .49 and 57.1% vs 83.3%, P = .11, respectively). Additionally, the median time to conduit replacement and catheter-based conduit interventions were comparable. In multivariable analysis, conduit size, but not conduit type, was a predictor of conduit revision (hazard ratio: 1.66, 95% confidence interval: 1.11-2.49, P = .02). At five-year and ten-year follow-up, patients with PTFE conduits had better survival than those with homograft conduits (100.0% vs 71.4%, P = .02); however, no mortalities were associated with conduit reoperations or catheter-based reinterventions. Conclusions: Polytetrafluoroethylene and homograft RVOT reconstruction in neonatal TA repair demonstrate similar durability as defined by reoperation and reintervention rates. The validation of the durability of PTFE conduits in neonatal TA repair requires confirmatory studies in larger cohorts.

Conduits for Right Ventricular Outflow Tract Reconstruction in Infants and Young Children

“…Mercer et al reported a similar performance for bicuspid ePTFE valved conduits with homograft conduits in patients <2 years of age (59). Another study from this team focusing on neonatal truncus arteriosus repair also showed similar durability, with 10-year freedom from replacement of 27.3 and 28.5% respectively for ePTFE valved conduit and homograft conduit (60).…”

Conduits for Right Ventricular Outflow Tract Reconstruction in Children: Are We Improving?

“…When analyzed with these criteria, the data from Seese et al suggest that although both conduits had similar outcomes at ten years of follow-up, conduit dysfunction due to stenosis tended to occur earlier in the PTFE group. 6 The data, as presented in the manuscript, may raise some questions. Kaplan-Meier curves demonstrated the same freedom from gradient 40 mm Hg, freedom from reoperation, and freedom from all interventions in the homograft group, namely, 71.4% at eight years.…”

“…As previously demonstrated by others, 8,9 Seese et al have also found conduit size as a risk factor for earlier failure with a hazard ratio of 1.66 per mm of decreasing graft diameter. 6 Because conduit diameter during primary implantation was smaller in the homograft group, it is reasonable to speculate that this may have at least partially influenced rates and timing for reinterventions.…”

“…5 In this issue of the World Journal for Pediatric and Congenital Heart Surgery, Seese et al presented a series of neonatal truncus arteriosus repair and concluded that PTFE conduits and homografts had similar performance when judged by reoperation and catheterbased reintervention rates. 6 Although these end points are indeed clinically relevant, they may not be the most appropriate to compare the merits and true outcomes of different conduits. Timing to reintervention varies markedly depending on institutional policies and thus prone to introduce important bias when used to analyze conduit performance.…”

“…12 Hopefully, future research work will enable better understanding of cell-matrix interactions and the role of mechanical and humoral signals and factors that will allow the development of a graft capable of remodeling and growth, resembling the fate of pulmonary autografts when implanted in aortic position. 13 While conduit choice still appears to be partially driven by personal surgeon's preference, continued, detailed, and careful patient surveillance as performed by Seese et al 6 and additional controlled comparative clinical studies will be essential in determining the best conduit for RVOT reconstruction based in solid scientific evidence. The quest for a better RVOT conduit still goes on .…”