Use of Fresh Decellularized Allografts for Pulmonary Valve Replacement May Reduce the Reoperation Rate in Children and Young Adults

Abstract

Background— Degeneration of xenografts or homografts is a major cause for reoperation in young patients after pulmonary valve replacement. We present the early results of fresh decellularized pulmonary homografts (DPH) implantation compared with glutaraldehyde-fixed bovine jugular vein (BJV) and cryopreserved homografts (CH). Methods and Results— Thirty-eight patients with DPH in pulmonary position were consecutively evaluated during the follow-up (up to 5 years) including medical examination, echocardiography, and MRI. These patients were matched according to age and pathology and compared with BJV (n=38) and CH (n=38) recipients. In contrast to BJV and CH groups, echocardiography revealed no increase of transvalvular gradient, cusp thickening, or aneurysmatic dilatation in DPH patients. Over time, DPH valve annulus diameters converge toward normal z -values. Five-year freedom from explantation was 100% for DPH and 86±8% and 88±7% for BJV and CH conduits, respectively. Additionally, MRI investigations in 17 DPH patients with follow-up time >2 years were compared with MRI data of 20 BJV recipients. Both patient groups (DPH and BJV) were at comparable ages (mean, 12.7±6.1 versus 13.0±3.0 years) and have comparable follow-up time (3.7±1.0 versus 2.7±0.9 years). In DPH patients, the mean transvalvular gradient was significantly ( P =0.001) lower (11 mm Hg) compared with the BJV group (23.2 mm Hg). Regurgitation fraction was 14±3% and 4±5% in DPH and BJV groups, respectively. In 3 DPH recipients, moderate regurgitation was documented after surgery and remained unchanged in follow-up. Conclusions— In contrast to conventional homografts and xenografts, decellularized fresh allograft valves showed improved freedom from explantation, provided low gradients in follow-up, and exhibited adaptive growth.