Right Ventricular Outflow Tract Reconstruction in Ross Patients: Does the Homograft Fare Better?

Abstract

In the Ross aortic valve replacement (AVR) procedure, the right ventricular outflow tract (RVOT) conduit is inserted in an orthotopic position. In complex congenital RVOT obstruction, the right ventricular-pulmonary artery (RV-PA) conduit is placed in a more heterotopic position. We hypothesized that durability of homograft RVOT reconstruction in the Ross AVR is improved secondary to orthotopic positioning and the ability to oversize the RV-PA homograft conduit in the Ross AVR. Between June 1993 and May 2007, 183 consecutive patients (mean age, 23.3 +/- 15.2; median, 22; range, 1 month to 61 years) underwent Ross AVR with RVOT reconstruction using a cryopreserved pulmonary homograft (n = 156), decellularized pulmonary homograft (n = 22), and bovine jugular vein conduit (n = 5). Three patients died (2 early, 1 late; mean follow-up, 5.7 +/- 3.3 years). Twenty-four patients (13%) had a peak systolic RVOT gradient exceeding 20 mm Hg, 5 (3%) had a gradient exceeding 40 mm Hg, and 7 (4%) had more than 2+ RVOT insufficiency. Eight patients (4%) underwent conduit replacement for RV dysfunction. Freedom from RVOT reoperation at 10 years is 96%. Freedom from RV failure and dysfunction are 98% and 96% at 5 years and 96% and 93% at 10 years, respectively. Independent predictors of pulmonary homograft RV-PA conduit dysfunction are smaller (< 14 mm) RVOT conduit size (p = 0.03) and follow-up exceeding 5 years (p = 0.05). Stenosis and regurgitation of the RV-PA conduit in adults and children following Ross AVR is infrequent. The most logical reasons for the superior performance of the homograft in Ross patients are: (1) orthotopic positioning, (2) older age of implant, and (3) the ability to significantly oversize the homograft in Ross patients.