Transplantation in the single ventricle population

Abstract

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 multidisciplinary 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.

Current spectrum, challenges and new developments in the surgical care of adults with congenital heart disease

“…Cardiovasc Diagn Ther 2018;8(6):754-764 cdt.amegroups.com especially in patients with situs inversus or single ventricle (65). Furthermore, due to multiple blood transfusions during previous surgeries, the presence of donor specific antihuman leukocyte antigen (HLA) antibodies is much more common in ACHD than in non-ACHD, thus prolonging the waiting time for an appropriate organ and increasing the risk of postoperative organ failure (66).…”

Sizing heart transplant donors in adults with congenital heart disease

“…14 Some centers have extrapolated these findings to patients with CHD undergoing HT and developed a practice of empirically oversizing donors. 15,16 These centers argue that empiric oversizing of donors may improve right ventricular-pulmonary arterial coupling and prevent graft failure in the face of underappreciated pulmonary vascular disease. 8,[15][16][17] These centers emphasize that hemodynamic assessment of PH in adults with CHD, specifically those with single-ventricle Fontan circulation, remains challenging, as these patients may have multiple shunts, nonpulsatile blood flow, and asymmetric pulmonary blood flow.…”

Superior Cavopulmonary Connection: Its Physiology, Limitations, and Anesthetic Implications

“…Due to the paucity of donor hearts available and because many patients have contraindications to transplantation, performance of a high-risk Fontan procedure may be attempted. 46,47 Acute failure of the Fontan circulation is unusual in well-selected patients. Initially, failing Fontan patients may have a fenestration enlarged, reopened, or created in the cardiac catheterization laboratory in order to try to palliate the patient.…”