Revisiting APOLT for Metabolic Liver Disease

Abstract

Even though auxiliary partial orthotopic liver transplantation (APOLT) as a technique was popularized in the late 80s, its role in metabolic liver disease remains controversial. The slow progress in gene therapy research, high incidence of technical complications, and the problem of long term graft atrophy have been roadblocks to its wider application. Better understanding of reciprocal dynamics of portal flow and regeneration between the graft and native liver along with multiple refinements in surgical technique have improved the outcomes of this operation, making it a safe alternative to orthotopic liver transplantation for patients with a wide range of noncirrhotic metabolic liver diseases (NCMLD). The ability to perform APOLT safely has also opened up a range of exciting indications in the setting of NCMLD. This article reviews the current status of APOLT for NCMLD, technical refinements which have improved outcomes and novel indications, which have rekindled fresh interest in this procedure.

Auxiliary Partial Orthotopic Liver Transplantation for Selected Noncirrhotic Metabolic Liver Disease

“…APOLT, being a form of partial LT, does not require a complete PV and IVC clamping. In addition, the systemic reperfusion syndrome is minimal because of the small volume graft and a near‐normally functioning native liver serving the patient throughout the operative period, improving intraoperative patient stability . This was evident by a lower peak and end of surgery lactate in the APOLT group.…”

“…APOLT was initially offered for children with NCMLD with the hope that future development of less invasive therapies like gene therapy or hepatocyte transplantation would provide permanent therapeutic options in their adult life . It was argued that once gene therapy is clinically available, the native remnant liver can be treated and that these patients will be able to come off immunosuppression.…”

“…In the LDLT setting, LLS donation is a safer operation for the donor as compared with a right lobe or LL donation. Similarly, a classical split is much more straightforward for most centers and will leave the extended right lobe for an adult recipient …”

“…The technique of OLT for NCMLD involved standard inferior vena cava (IVC) preserving hepatectomy after complete portal vein (PV) and IVC clamping. The technique of APOLT for MLD has previously been described by us in detail . Briefly, left‐sided APOLT was preferred, unless the patient was over 50 kg and/or had an organic acidemia, wherein a right lobe APOLT was favored.…”

“…Auxiliary partial orthotopic liver transplantation (APOLT) is a technically complex procedure, where a segmental liver graft is implanted orthotopically following a native liver partial hepatectomy. Despite several purported advantages, it is not widely accepted by the transplant community due to the technical complexity of the procedure, higher risk of technical complications, and concern of longterm graft atrophy due to portal steal . APOLT has a wider acceptance in acute liver failure (ALF), where it acts as a bridge to native liver regeneration, with a possibility of becoming immunosuppression free …”