Use of fresh decellularized allografts for pulmonary valve replacement may reduce the reoperation rate in children and young adults: early report.

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.

Temporary cardiac support with a mini-circuit system consisting of a centrifugal pump and a membrane ventilator.

Commonly used extracorporeal membrane oxygenation (ECMO) systems for cardiac support are limited by bleeding complications, especially after surgery in the adult patient. Recently, we have switched from the use of a conventional ECMO system to a miniature-circuit including a centrifugal pump and the Novalung membrane ventilator (iLA). This system allows us to administer less heparin compared to the conventional system. Between January and August 2007, 1469 patients underwent cardiac surgery at our center, of which 18 patients (1.2%) required temporary postoperative ECMO system support. Surgical procedures in these patients included coronary artery bypass grafting (CABG) surgery (n=5), valvular replacement (n=2), aortic surgery (n=2), cardiac transplantation (n=5), and other procedures (n=3). The mean age of the 18 patients was 50+/-15 years (n=13 male) with a mean duration of ECMO system support of 4.3 days (range: <1 to 14 days). Twelve patients (67%) were successfully weaned from ECMO system. The 30-day survival was 44% with a hospital mortality of 61%. Re-thoracotomy for bleeding was necessary in six patients (33%) under ECMO system support. In summary, the miniature ECMO system circuit seems to be suitable for middle-term cardiac support and is associated with a low rate of bleeding complications.