Ricerc@Sapienza

Background: The Aberrant Left Hepatic Artery (ALHA) is replaced when it does not originate
from the hepatic artery proper and it is the only supply to that part of the liver, while an
accessory artery coexists with a normal artery. The aim of this systematic review is to
evaluate the incidence of ALHAs including the one arising from the Left Gastric Artery, also
named Hyrtl's artery.
Methods: A literature search in PubMed, SCOPUS,WOS andGoogle Scholarwas performed. The
risk of biaswas assessed bymeans of the AQUA tool. Themain outcomewas the prevalence of
ALHA. Secondary outcomes were the prevalence of the accessory and replaced left hepatic
arteries. A subgroup analysis was conducted by geographic region and type of evaluation.
Results: This review included 57 studies, with a total of 19,284 patients. The majority of the
studies involved the use of radiological techniques -especially Angio-CT-and were performed
in Asia. The overall risk of bias was moderate. The overall prevalence of the ALHA
was 13.52%; the overall prevalence was 8.26% for the Replaced ALHA and 5.55% for the
Accessory ALHA. In the 18 studies that employed Michels' classification, Type II had the
lowest prevalence (0.36%) and Type VII the highest prevalence (6.62%).
Discussion: Some of the studies included did not distinguish between the ‘‘replaced’’ and
‘‘accessory’’ ALHA (34.25%). Some surgical dissection techniques proved insufficient for the
localization of other hepatic arteries. These results suggest that an accurate preoperative
radiological evaluation is needed to localize replaced arteries.