Bovine valved venous xenografts for RVOT reconstruction: results after 71 implantations1

Background: Pediatric right ventricular outflow tract (RVOT) reconstruction with homo- or porcine xenografts is problematic because of limited availability, lack of material for reconstruction, early degeneration, and tissue ingrowth. Contegra®, a bovine jugular vein graft, might be an interesting alternative to overcome these problems. Patients and methods: Within a Federal Drug Administration controlled study, we implanted 71 Contegra® pulmonary valved conduits from May 1999 to September 2001 in 71 patients (male/female 33/38) in the age range 2 days–17.4 years, median 1.2 years. Twenty five were primary repairs, 22 had previous graft implantations, and 24 had other repairs/palliations. Preoperative diagnoses: truncus arteriosus communis (19 patients), tetralogy of Fallot (32), double outlet right ventricle (13), transposition of the great arteries (5), and two rare complex malformations. The size of implanted Contegra® conduits ranged from 12 to 22 mm. Echocardiography was performed at 1 and 3 months, and then every 3 months postoperatively. Follow-up time was 27 months (maximal), 80 years in total. Results were compared with our 52 homograft- and 30 Tissuemed® porcine xenograft recipients. Results: Contegra® enables the surgeon to perform all anastomoses without additional material. Its tissue is very apt for suturing and its insufficiencies are common, but without clinical significance or tendency to increase. We saw no sign of conduit or valve degeneration during the whole follow-up up to 27 months. There were no device related adverse events. Redos: five for peripheral pulmonary arteries, two residual ventricular septum defect (VSD) closures. There were six deaths (five early, one late). The maximal transvalvular gradients of 25–42 mmHg were measured in seven patients; these gradients did not increase further during the follow-up. Six patients with completely intact Contegra® conduits developed pressure gradients of more than 70 mmHg immediately distal from the conduit. At 27 months, Contegra® grafts were advantageous compared to homografts with respect to survival and freedom from explantation. Right ventricle to left ventricle (RV/LV) ratio development and freedom from explantation/redo were equal for Contegra® conduits and homografts. Porcine Tissuemed® xenografts were significantly inferior. Conclusion: The Contegra® conduit offers unique tailoring and suturing options for primary and redo RVOT reconstruction. At 27 months, its durability seems at least equivalent to homografts and is superior to porcine Tissuemed® xenografts.