Midterm results of size-reduced cryopreserved homografts for right ventricular outflow tract reconstruction

Size reduction of valved homografts has been investigated for right ventricular outflow tract reconstruction because of limited supply of small-sized grafts. However, follow-up results are lacking.

From 1997 to 2007, 45 patients underwent placement of 34 pulmonary and 11 aortic, size-reduced bicuspid homografts for right ventricle to pulmonary artery connection, which was part of a Rastelli-type operation (n = 35; 78%), redo right ventricular outflow tract reconstruction (n = 5; 11%), double-switch operation (n = 3; 7%), or palliative right ventricle to pulmonary artery connection (n = 2; 4%). Mean age at surgery was 20.0 +/- 24.4 months. Twenty patients (44%) were younger than 1 year old. Mean body weight was 9.6 +/- 7.1 kg. Diameter of the bicuspid conduit was 15.0 +/- 1.5 mm (z value, 3.4 +/- 1.9). Graft dysfunction was defined as pressure gradient greater than 50 mm Hg or moderate or greater regurgitation on follow-up echocardiography. Survival, freedom from graft explantation, and freedom from graft dysfunction were estimated by the Kaplan-Meier method. Risk factor for graft dysfunction was evaluated by multivariate analysis.

There were 2 (4.4%) early deaths. During a mean follow-up of 49.4 +/- 37.2 months, 13 patients showed graft dysfunction. Five of them had their grafts explanted. Freedom from graft explantation was 100% at 1 year after implantation, 97.4% +/- 2.5% at 3 years, and 89.0% +/- 6.2% at 5 years. Freedom from graft dysfunction was 92.4% +/- 4.2% at 1 year, 78.8% +/- 7.3% at 3 years, and 52.9% +/- 10.9% at 5 years. Diagnosis of truncus arteriosus was identified as a factor for graft dysfunction (p = 0.028).

Size-reduced homografts may provide an alternative for right ventricular outflow tract reconstruction when an appropriately sized homograft is unavailable.