Aortic valve replacement using On-X valve in a child postorthotopic heart transplantation.

A 20-month-old girl presented with severe dilated cardiomyopathy and decompensated congestive cardiac failure. Despite escalating inotropic and mechanical ventilation support, she required placement on extracorporeal membrane oxygenation and transfer to the transplant centre in Newcastle, England. She was placed on biventricular assist device and then Berlin Heart but failed to show any recovery of ventricular function. She underwent orthotopic heart transplantation at 2 years of age. She developed bacterial endocarditis with Enterococcus faecalis resulting in severe aortic valve regurgitation requiring aortic valve replacement with a 19 mm On-X valve (Airtivion) 11 days after her transplant. Given the size of the donor heart, it was possible to implant a 19-mm valve in this 12 kg child with minimal risk of patient prosthesis mismatch. She was anticoagulated with warfarin (On-X valve INR 2-3 for first 3 months; INR 1.5-2.0 thereafter). Although she suffered several other post-operative complications, including malabsorption, nasojejunal feeding, liver dysfunction, vertebral fractures, renal impairment and renal calcification, and need for repeat opening of her tracheostomy site following her initial decannulation, her aortic valve function has remained stable.

Transplantation in the single ventricle population.

The single ventricle patient population comprises the most complex cohort presenting to the cardiac transplant team, in terms of demographics, anatomic substrate, and unique physiology. It is also the most rapidly growing diagnostic group presenting for heart transplantation. In this manuscript, we aim to describe the changing landscape of transplantation in single ventricle conditions through reflection on our own institution's practice and experience, alongside contemporary literature review. Single ventricle patients are heterogeneous in terms of age, anatomic diagnosis and physiology according to surgical stage of repair. Progress in surgical palliative strategies has impacted upon the present composition of the population, with growing numbers of hypoplastic left heart syndrome patients and those with late physiology failure following Fontan completion. Multiple prior surgeries, immunological sensitivity and multi-organ involvement impart high peri-operative risk but can be mitigated in part by careful pre-operative planning by a dedicated multi-disciplinary team addressing issues such as planning of concurrent reconstructive surgery, minimizing the post-operative effect of collaterals, timely harvesting, oversizing of donor organs to minimize graft failure, and strategies to address anticipated post-operative elevation in pulmonary vascular resistance. Determining optimal timing for transplant in these patients remains unclear, but understanding the risk of alternative surgical options can help guide decision making with regards to listing.