Application of preoperative portal vein embolization before major hepatic resection in patients with normal or abnormal liver parenchyma.

BACKGROUND: Clinical parameters influencing the effect of preoperative portal vein embolization (PVE) in hypertrophying the nonembolized lobe of patients with either normal or abnormal liver parenchyma and its effect upon portal pressure were examined to identify the patient population for whom this approach is most suited. METHODS: The study population included 43 patients undergoing major hepatectomy after PVE. Patients were divided into 2 groups according to their liver parenchyma: 17 patients with normal liver parenchyma (N group) and 26 patients with damaged liver parenchyma due to viral hepatitis (D group). We calculated the correlation between volumetric increases in the nonembolized (left) lobe after PVE (hypertrophic ratio = post-PVE left lobe volume/pre-PVE left lobe volume) using computed tomography volumetry before and 2 weeks after PVE. Clinical parameters also were examined to identify those parameters modifying the hypertrophic ratio in each group, and changes in portal pressure by PVE and the subsequent hepatectomy were recorded. Finally, by comparing patients with or without postoperative liver failure after hepatectomy, the influence of the hypertrophic ratio and portal pressure on the outcome of subsequent hepatectomy was examined. RESULTS: The hypertrophic ratio was 1.34 +/- 0.23 in the N group, and 1.25 +/- 0.21 in the D group. This difference was not significant. Multiple regression analysis revealed that the parenchymal volumetric rate of the right lobe (PVR) in the D group and both PVR and prothrombin time in the N group were independent parameters predicting the hypertrophic ratio. The portal pressure increased immediately after PVE and was similar in both groups to levels after hepatectomy. Six patients in the D group experienced postoperative liver dysfunction. In 5 of these 6 patients, the hypertrophic ratio was below 1.2, and the portal pressure was higher than that in patients without liver dysfunction. CONCLUSIONS: PVE induces hypertrophy of the nonembolized lobe of both abnormal and normal liver parenchyma, and the effect was predictable. Postoperative liver failure appeared to be more severe in patients having a lower hypertrophic ratio and higher portal pressure in abnormal liver parenchyma, however. PVE also may have diagnostic use in predicting portal pressure after hepatectomy, which may be associated with surgical outcome.