Preoperative hepatic venous embolization for partial hepatectomy combined with segmental resection of major hepatic vein

The Influence of Interdisciplinary Work towards Advancing Knowledge on Human Liver Physiology

The knowledge accumulated throughout the years about liver regeneration has allowed a better understanding of normal liver physiology, by reconstructing the sequence of steps that this organ follows when it must rebuild itself after being injured. The scientific community has used several interdisciplinary approaches searching to improve liver regeneration and, therefore, human health. Here, we provide a brief history of the milestones that have advanced liver surgery, and review some of the new insights offered by the interdisciplinary work using animals, in vitro models, tissue engineering, or mathematical models to help advance the knowledge on liver regeneration. We also present several of the main approaches currently available aiming at providing liver support and overcoming organ shortage and we conclude with some of the challenges found in clinical practice and the ethical issues that have concomitantly emerged with the use of those approaches.

Left trisectionectomy combined with resection of the right hepatic vein and inferior vena cava after right hepatic vein embolization for advanced intrahepatic cholangiocarcinoma

Background

When the inferior right hepatic vein (IRHV) is present, left hepatic trisectionectomy with resection of the right hepatic vein (RHV) is theoretically possible without reconstruction of the RHV. We here report a successful case of this extended hepatectomy after RHV embolization for advanced intrahepatic cholangiocarcinoma.

Case presentation

A 71-year-old man was admitted to our clinic with abdominal pain. Computed tomography showed a cholangiocarcinoma located at the caudate lobe that involved the inferior vena cava (IVC) and the roots of the three major hepatic veins. Portal vein embolization of the left and right anterior portal veins was performed. As the IRHV was present but thin, RHV was also embolized. Left hepatic trisectionectomy with resection of the involved IVC and RHV, preserving the IRHV, was done. The IVC was reconstructed with artificial graft. The patient was discharged on postoperative day 36.

Conclusion

RHV embolization is useful in extended left trisectionectomy with resection of the RHV when the IRHV is present but thin.

Usefulness of artificial vascular graft for venous reconstruction in liver surgery

Background

The purpose of this study was to evaluate the results of hepatectomy with inferior vena cava or hepatic vein resection, followed by vessel reconstruction with an artificial vascular graft.

Methods

From 2000 to 2011, 1,434 patients underwent several types of hepatectomy at our institution. Of these, we reviewed the cases of eight patients (0.56%) who underwent hepatectomy with inferior vena cava or hepatic vein resection and subsequent reconstruction using an expanded polytetrafluoroethylene (PTFE) graft.

Results

We resected the inferior vena cava in six patients and the hepatic vein in two patients. All eight patients underwent subsequent reconstruction using an expanded PTFE graft. The median operative time was 443 minutes and the median blood loss was 2,017 mL. The median postoperative hospital stay period was 18.5 days and the in-hospital mortality rate was 0%. Complications occurred in four patients: two patients experienced bile leakage, one experienced a wound infection, and one experienced pleural effusion. The two patients who experienced bile leakage had undergone reoperation on postoperative day 1. No complication with the artificial vascular graft occurred in these eight cases. Histological invasion to the replaced inferior vena cava or hepatic vein was confirmed in four cases. All artificial vascular grafts remained patent during the observation period.

Conclusions

Hepatectomy combined with inferior vena cava or hepatic vein resection, followed by reconstruction with an expanded PTFE graft can be performed safely in selected patients.

Sequential preoperative ipsilateral hepatic vein embolization after portal vein embolization to induce further liver regeneration in patients with hepatobiliary malignancy

OBJECTIVE

To assess the effect of ipsilateral hepatic vein embolization (HVE) performed after portal vein embolization (PVE) on liver regeneration.

SUMMARY BACKGROUND DATA

PVE induces shrinkage of the embolized lobe and compensatory enlargement of the non-embolized lobe, but it does not always induce sufficient liver regeneration. There was no effective method to accelerate liver regeneration in addition to PVE yet.

METHODS

During a 1-year study period, preoperative HVE were performed on 12 patients who had shown limited liver regeneration after PVE awaiting right hepatectomy. The right hepatic vein was embolized with multiple coils after insertion of vena cava filters or vascular plugs.

RESULTS

No HVE procedure-related complications occurred, but embolization of the wrong hepatic vein trunk occurred in 1 patient. The increase in blood liver enzymes after HVE was comparable with that after PVE alone. In 9 patients who underwent hepatectomy, the proportions of future liver remnant volume to total liver volume were 34.8% +/- 1.5% before PVE, 39.7% +/- 0.6% 1 to 2 weeks after PVE, 44.2% +/- 1.1% 2 weeks after HVE, and 64.5% +/- 6.2% 1 week after right hepatectomy. Cirrhotic livers showed lower regeneration rates following HVE after PVE and 1 patient underwent hepatectomy 17 months after HVE. Immunohistochemistry showed that apoptosis occurred more in the liver area affected by both PVE and HVE than in that affected by PVE alone.

CONCLUSIONS

Preoperative sequential application of PVE and HVE seems to be safe and effective in facilitating contralateral liver regeneration by inducing more severe liver damage than PVE alone.

Impact of hepatic vein deprivation on liver regeneration and function after major hepatectomy

BACKGROUND AND AIMS

In extended liver resections, the preservation of vascular and biliary structures of the entire remnant liver is of paramount importance. The impact of venous outflow impairment and its consequences for liver regeneration and function are still a matter of debate.

MATERIALS AND METHODS

Rats (n = 75) were subjected to a 90% partial hepatectomy (PH), to a 70% liver resection with narrowing of the hepatic outflow of an additional 20% parenchyma (70%+ PH) or to an anatomic 70% PH. Postoperatively hepatocyte proliferation (Ki-67), liver function and survival were assessed. Gene expression analysis for markers of regeneration was determined by in-house complementary (DNA) arrays and quantitative real-time polymerase chain reaction (RT-PCR).

RESULTS

Ninety percent PH led to a greater regenerative response as shown Ki-67 compared to animals with a 70%+PH (p < 0.05). However, liver function was equally impaired in both groups. Rats with 70% PH showed a greater proliferation index with less hepatic injury and better liver function. While mortality was 0% in the group of 70% PH, rats with 90% PH and 70+PH had a reduced survival of 75% (p < 0.05)

CONCLUSION

Venous outflow obstruction leads to an impairment of liver regeneration and liver function. In cases with critically small liver remnants, restoration of an adequate venous outflow may be mandatory.

Safety and Effectiveness of Left Hepatic Trisegmentectomy for Hilar Cholangiocarcinoma

Left hepatic trisegmentectomy has been performed for huge malignant tumors, but it is rarely applied in patients with hilar cholangiocarcinoma. Twelve consecutive patients (7 men and 5 women; mean age, 64 years) underwent left hepatic trisegmentectomy in our institution between January 2000 and December 2003. The preoperative management and postoperative outcomes of this surgical procedure were presented and retrospectively analyzed. Preoperative biliary drainage and portal vein embolization were performed in 6 patients (50%) and 9 patients (75%), respectively. The preoperative estimated volume ratio of the posterior segment /the whole liver was 44.8 +/- 7.0% (34.3-54.3), the plasma retention rate of indocyanine green at 15 minutes was 8.6 +/- 2.2% (4.7-13.7), and the serum total bilirubin level before surgery was 1.0 +/- 0.4 mg/dl (0.4-1.7). The serum total bilirubin level on the first postoperative day was 3.3 +/- 0.4 mg/dl (1.4-6.2). There was no hospital death or postoperative hepatic failure. The incidence of positive resectional margin was 25%. With biliary decompression and preoperative portal embolization techniques, left hepatic trisegmentectomy was a safe and curative resectional option for hilar cholangiocarcinoma.

Animal models of liver regeneration

Owing to its powers of regeneration, the liver is capable of in vivo "tissue engineering" which enables complete restoration of liver architecture and re-establishment of the specific functions of the liver after various types of liver injury. Our current understanding of liver regeneration forms the basis of modern liver surgery and is now taken into consideration in the treatment of many liver diseases, in liver transplantation and hepatic tissue engineering. These advances have been achieved primarily by studies of liver regeneration in animal models after partial hepatectomy, attention being focused on the general mechanisms of cell proliferation. In recent years, however, toxin-induced models of liver regeneration have assumed growing importance, and by studying the interaction between cell damage and cell regeneration have made possible an investigation of liver regeneration of greater clinical relevance. However, the mechanisms of liver regeneration in patients with pre-existing chronic liver damage such as liver cirrhosis are still largely unexplored. This review examines and critically appraises the various approaches to the study of liver regeneration in animal models, including both surgical and pharmacological approaches.

Significant role of middle hepatic vein in remnant liver regeneration of right-lobe living donors

For adult patients with end-stage liver disease, living-donor liver transplantation (LDLT) of right-lobe grafts with or without the middle hepatic vein (MHV) has been increasingly used in recent years. We investigated the role of the MHV in donor remnant liver regeneration after right-lobe LDLT, which has not been described in previous studies. A total of eight living donors were included in this study of right-lobe LDLT. Four donors underwent right lobectomy (without MHV), and the remaining four underwent extended right lobectomy (with MHV). Regeneration of the donor remnant liver was assessed by volumetric computed tomography studies before and 90 days after LDLT. Comparison between the right-lobe and extended right-lobe donors did not show a clear-cut difference in the net increase of remnant liver volume at 3 months. However, the mean volume increase of the medial segment at the 90th postoperative day was 7% in the extended right-lobe donors and 61% in the right-lobe donors, showing a lower value in the remnant livers without MHV. The MHV plays a specific role in remnant liver regeneration of right-lobe living donors. We expect that this knowledge will contribute to securing a margin of safety in right-lobe LDLT.