Effect of Preoperative Portal Vein Embolization on Liver Volume and Hepatic Energy Status of the Nonembolized Liver Lobe in Humans

Abstract

Clinically portal vein embolization (PVE) is presently preferred to extended hepatectomy. Nevertheless, its effect on hepatic adenosine triphosphate (ATP) and energy charge levels, which are essential for organ viability, has been little studied in humans. Fourteen patients with (n = 7) and without (n = 7) preoperative right PVE participated in this study. Changes in hepatic lobar volume and serum liver function tests were examined before and after percutaneous transhepatic right PVE. Liver volume (cm³) was calculated on computed tomograms before and 20 ± 3 days after PVE. At the time of surgery (mean of 25 days after PVE), small liver specimens were obtained from portal vein (PV) nonembolized left lobes immediately after laparotomy without any ischemic procedures. Concentrations of adenine nucleotides were measured by high performance liquid chromatography, and hepatic energy charge levels were calculated. These values were compared with those in control patients who had not undergone preoperative PVE. Serum liver function tests including the indocyanine green retention rate did not differ significantly before and after PVE. The volume of the PV-nonembolized left lobe significantly increased after right PVE (from 473 ± 32 to 624 ± 66 cm³), with a significant increase in the percentage of the left lobe to total liver volume. The concentrations of AMP, ADP, and ATP, and hepatic energy charge levels in the PV-nonembolized left lobe were similar to those of the control liver. These results suggest that preoperative right PVE increases the volume of the nonembolized left lobe, keeping the hepatic engery charge and ATP levels similar to the control liver, thereby increasing the total amount of ATP and hepatic energy reserve of the PV-nonembolized lobe in proportion to its volume increase at the time of surgery.