Liver transplantation for patient with variant hepatic artery arising from right renal artery: a case report

Replaced right hepatic artery arising from the distal renal artery, a new variation

PURPOSE

Arterial irrigation of the liver is highly variable and widely studied due to its importance in the correct planification of the surgical or endovascular treatment of the hepatobilary area. Various classifications have been published of the common and uncommon anatomic variations of the hepatic arterial distribution. While the classic anatomic pattern of the proper hepatic artery-when it originates from the celiac trunk dividing into left and right branches-represents 50-83% of the described patterns, there are numerous uncommon distributions based on the presence of replaced or accessory hepatic arteries. In this article, we present a case of a replaced right hepatic artery originating from the right distal renal artery.

METHODS

Contrast enhanced computed tomography (CECT) examination was performed on a 67 years-old male patient with compensated alcoholic cirrhosis as part of the disease monitoring.

RESULTS

The replaced right hepatic artery of the patient arises from the right distal renal artery and-after its cranial course-enters the porta hepatis posterior to the main portal vein. After giving off the cystic artery, it irrigates the right hepatic lobe. The left hepatic artery does not show any variation.

CONCLUSION

We present CT angiography images of an extremely rare anatomic variation of the hepatic arterial irrigation in a cirrhotic patient.

A rare hepatic artery variant reporting and a new classification

Variations of the hepatic artery are very common, but they greatly increase the difficulty of surgery and the risk of complications in perihepatic surgeries such as liver transplantation, liver segmentectomy, and gastroduodenal surgery. Thus, it is important to precisely define the type of hepatic artery variant before surgery. However, there are often rare variants that cannot be defined with existing classifications. For example, the type of hepatic artery variant in the current case could not be classified with conventional classifications, and no such variation has been reported to date, involving two accessory left hepatic arteries from the common hepatic and left inferior phrenic arteries, respectively. Based on the existing 3DCT technology and the CRL classification method, which is applicable to the most common hepatic artery variants, we reviewed many rare variant types and proposed a new classification method (ex-CRL classification) for hepatic artery variations that do not fit the classic scope. The ex-CRL classification can accurately classify the vast majority of rare cases in the literature, greatly compensates for the limitations of current hepatic artery classifications, improves the generalization and understanding of rare cases, and reduces surgical complications.

Anatomical variation and its management in transplantation

Variant anatomy may be challenging at retrieval, with failure to identify variance being associated with organ damage, particularly vascular damage. On implantation, some variants demand nonstandard techniques of reconstruction or implantation. This review covers the common and less common anatomical variants of the liver, kidney and pancreas, and gives guidance as to how they may be managed during organ retrieval and implantation.

Different modalities of arterial reconstruction in hepatic retransplantation using right partial graft

Though split-liver and living-related transplantation are routinely performed, they are done almost exclusively for primary liver transplantation because of potential surgical difficulties. These difficulties are generally related to arterial revascularization, particularly if there is hepatic artery thrombosis. According to UNOS data, of the hepatic retransplantations performed between 1996 and 2007, only 8.7% were done using right or extended right grafts from deceased donors, and 14.3% using right grafts from live donors. Here we report our experience with 5 hepatic retransplantations in which right partial grafts resulting from conventional in situ splits, and one right lobe resulting from an adult-to-adult living-related transplant, were successfully used with different modalities of graft arterialization.