eComment. Autologous pericardium is superior to conventional bovine patch in congenital heart disease reconstructive surgery: an appraisal for tissueengineered xenograft

[Prosthetic repair of aortic valve cusps with autopericardium in children. State of the art and prospects]

According to the results of modern researchers, the main techniques used in congenital pathology of the aortic valve in children include balloon catheter dilatation of the aortic valve, surgical valvuloplasty, the Ross procedure and replacement of the aortic valve with a mechanical prosthesis. Many surgeons point out that these techniques in congenital pathology of the aortic valve yield suboptimal results. This is often due to the lack of a clear-cut definition between surgeons as to what operation should be performed in a particular age group. According to the reports of the majority of researchers, biological prostheses undergo early degeneration and structural changes in paediatric cardiac surgery and yield the worst results. Comparing the main techniques, optimal haemodynamics is observed after the Ross procedure. A disadvantage of this operation is the necessity of repeat intervention on the right ventricular outflow tract, which is required in 20 to 40%. Concomitant surgery of the mitral valve and/or aortic arch during the Ross procedure significantly increases the lethality and the risk of postoperative complications. Compared with an adult cohort of patients, children after prosthetic repair of the aortic valve using a mechanical prosthesis are more often found to have postoperative complications and a higher mortality rate. Yet another problem encountered in paediatric valve surgery is the unavailability of commercial prostheses sized ?19 mm. The duration of the intraoperative parameters for reconstructions of the aortic valve, the Ross procedure, and replacement of the aortic valve by the results of many studies averagely amounts to 74±34 min, 100±56 min, and 129±71 min, respectively. Yet another method which can be used for neocuspidization of the aortic valve in reconstructive surgery of the aortic root in paediatric patients is the use of glutaraldehyde-treated autologous pericardium. In our opinion, given the simplicity of the procedure, duration of the intraoperative parameters, and acceptable initial results reported by some researchers, the Ozaki procedure may be performed in children.

Current surgical strategies and techniques of aortic valve diseases in children

While the long-term outcome of surgical aortic valvotomy (SAV) appears to be better than that of balloon aortic valvuloplasty (BAV) as the primary procedure of aortic valve stenosis, the surgical strategies and techniques of treating aortic valve disease in children in other situations remain controversial. Valve repair should be first considered while replacement is still unavoidable in some cases, and new repair techniques developed by innovative surgeons are gradually becoming adopted. Some complex repair procedures such as cusp extension, leaflet replacement/reconstruction have provided satisfactory outcomes. The Ozaki technique replaces aortic valve leaflets with glutaraldehyde-treated autologous pericardium instead of replacing the valve entirely. Special instruments have been developed to make the Ozaki technique more reproducible and standardized. Neonates and infants undergoing aortic valve replacement (AVR) are a high-risk group, where repair should be the primary consideration rather than replacement. Several systematic reviews reveal that all currently available aortic valve substitutes such as pulmonary autograft, mechanical prosthesis, homograft and bioprosthesis are associated with suboptimal results in children, but pulmonary autograft appeared to be superior with high freedom from reintervention and better hemodynamic performance. The strategy for treatment of aortic valve disease should be specifically analyzed based on the brief of being beneficial for children.