Gil-Chun Park

Usability of ringed polytetrafluoroethylene grafts for middle hepatic vein reconstruction during living donor liver transplantation

Large vein allografts are suitable for middle hepatic vein (MHV) reconstruction, but their supply is often limited. Although polytetrafluoroethylene (PTFE) grafts are unlimitedly available, their long‐term patency is relatively poor. We intended to enhance the clinical usability of PTFE grafts for MHV reconstruction during living donor liver transplantation (LDLT). Two sequential studies were performed. First, PTFE grafts were implanted as inferior vena cava replacements into dogs. Second, in a 1‐year prospective clinical trial of 262 adults undergoing LDLT with a modified right lobe, MHV reconstruction with PTFE grafts was compared with other types of reconstruction, and the outcomes were evaluated. In the animal study, PTFE grafts induced strong inflammatory reactions and luminal thrombus formation, but the endothelial lining was well developed. In the clinical study, the reconstruction techniques were revised to make a composite PTFE graft with an artery patch on the basis of the results of the animal study. MHVs were reconstructed with cryopreserved iliac veins (n = 122), iliac arteries (n = 43), aortas (n = 13), and PTFE (n = 84), and these reconstructions yielded 6‐month patency rates of 75.3%, 35.2%, 92.3%, and 76.6%, respectively. The overall 6‐month patency rates for the iliac vein and PTFE grafts were similar (P = 0.92), but the 6‐month patency rates with vein segment 5 were 51.0% and 34.7%, respectively (P = 0.001). The overall graft and patient survival rates did not differ among these 4 groups. In conclusion, ringed PTFE grafts combined with small vessel patches showed high patency rates comparable to those of iliac vein grafts; thus, they can be used for MHV reconstruction when other sizable vessel allografts are not available. Liver Transpl, 2012.

Pure Laparoscopic Versus Open Right Hepatectomy for Hepatocellular Carcinoma in Patients With Cirrhosis: A Propensity Score Matched Analysis.

Objective: We aimed to describe our experience with pure laparoscopic right hepatectomy (LRH) and to compare its outcomes with those of open right hepatectomy (ORH) in hepatocellular carcinoma (HCC) patients with liver cirrhosis. Background: Laparoscopic liver resection has been reported as a safe and effective approach for the management of liver cancer; however, its outcomes have not been evaluated in a large cohort of HCC patients with liver cirrhosis. Methods: We retrospectively reviewed the medical records of 152 patients who underwent pure LRH (n = 37) or ORH (n = 115) between June 2008 and July 2015 at the Asan Medical Center in Seoul, Korea. We performed 1:1 propensity score matching between the LRH and ORH groups. Subsequently, 33 patients were included in each group. Results: There was no statistically significant difference between the LRH and ORH groups regarding the rate of complications (P = 0.053). However, the mean comprehensive complication index, which accounts for the severity of complications, was significantly lower in the LRH group (0.63 vs 4.42; P = 0.025). There were no significant differences between the LRH and ORH groups regarding 2-year disease-free survival rate or 2-year overall survival rate (P = 0.645 and P = 0.090, respectively). Conclusions: Even in patients with cirrhosis, pure LRH is not less safe than the traditional open approach. The oncological outcomes of HCC were also comparable between the two groups. In selected patients, pure LRH for HCC appears to represent a viable alternative to ORH.

Biliary stricture is the only concern in ABO-incompatible adult living donor liver transplantation in the rituximab era

BACKGROUND & AIMS With the introduction of rituximab prophylaxis, the survival of ABO-incompatible (ABOi) adult living donor liver transplant (ALDLT) has been strikingly improved due to the decreased incidence of antibody-mediated rejection. However, biliary stricture (BS) related to ABO incompatibility remains an unresolved concern. METHODS Excluding 105 dual graft ALDLTs, 1102 ALDLT cases including 142 ABOi recipients were included in this study. The desensitization protocol for overcoming the ABO blood group barrier comprised pretransplant plasma exchange, and rituximab (300-375 mg/m(2) BSA). RESULTS The mean follow-up period was 34.2 ± 15.4 months. The cumulative graft and patient survival rates were comparable in the two groups. The 1- and 3-year BS-free survival rates of ABOi ALDLT were 81.5 and 79.0%, respectively, lower than those of ABOc ALDLT (87.6 and 85.7%, respectively, p=0.022). In the risk factor analysis, diameter of graft bile duct opening <5mm, antecedent acute cellular rejection, and ABO incompatibility were independent risk factors for BS. Diffuse intrahepatic biliary stricture (DIHBS) exclusively occurred in 12 patients (8.5%) receiving ABOi ALDLT. The deaths of 3 patients and 4 cases of re-transplantation were related to DIHBS. Graft and patient survival rates were significantly reduced in ABOi ALDLT recipients with DIHBS. However, we failed to identify any significant risk factors for DIHBS. CONCLUSIONS The incidence of BS in ABOi ALDLT is higher than in ABOc, mainly due to the fact of DIHBS which significantly affected survival outcomes. To predict and prevent DIHBS, we need further studies to identify significant risk factors.

Comparison of Laparoscopic Versus Open Left Hemihepatectomy for Left-Sided Hepatolithiasis

PURPOSE: The purpose of this study was to evaluate and compare the perioperative and long-term outcomes of open versus laparoscopic left hemihepatectomy (OLH vs. LLH) for left-sided hepatolithiasis. METHODS: Between October 2007 and June 2012, 149 patients with left-sided hepatolithiasis who underwent LLH (n = 37) or OLH (n = 112) were evaluated. The perioperative and long-term outcomes that were reviewed included the stone clearance rate, operative morbidity and mortality, and the stone recurrence rate. RESULTS: The mean operative time of the LLH group was significantly longer than that of the OLH group (257±50.4 minutes vs. 237±75.5 minutes, p = 0.022), but the mean hospital stay was significantly shorter (8.8±4.10 vs. 14.1±4.98 days, p < 0.001). Postoperative complications were noted in four and twenty cases among LLH and OLH patients, respectively (p = 0.982). The initial clearance rate of intrahepatic duct (IHD) stones was 100% and 96.4% in the LLH and OLH groups, respectively, but all remnant stones (n = 4, OLH group) were resolved postoperatively. There were two cases of recurrence of IHD stones in OLH patients, but none in LLH patients (p = 0.281). CONCLUSIONS: In left-sided hepatolithiasis, LLH was safe and effective: it resulted in low postoperative morbidity, no mortality and a high stone clearance rate, and there were no incidences of recurrence in our study. The potential benefits of LLH include a shorter hospital stay and a faster return to oral intake. If consideration is given to the appropriate indication criteria, including the extent of hepatectomy and the location and distribution of lesions, LLH may be an excellent choice for treatment of left-sided hepatolithiasis.

Effect of Pulmonary Support Using Extracorporeal Membrane Oxygenation for Adult Liver Transplant Recipients With Respiratory Failure

BACKGROUND Adult liver transplantation (OLT) recipients occasionally show serious acute cardiopulmonary dysfunction, requiring intensive care. We assessed the role of extracorporeal membrane oxygenation (ECMO) support in adult recipients facing acute pulmonary failure and refractory to conventional mechanical ventilation and concurrent nitric oxide gas inhalation. METHODS From January 2008 to March 2011, 18 adult OLT recipients at our institution required ECMO support: 12 due to pneumonia and 6 to adult respiratory distress syndrome. Their mean age was 55.7 ± 6.9 years and mean Model for End-stage Liver Disease score, 24.8 ± 8.5. Twelve patients had undergone living donor and six deceased donor OLT. RESULTS A venovenous access mode and concurrent continuous venovenous hemodiafiltration were used in all patients. There were no procedure-related complications. Eight patients (44.4%) were successfully weaned from ECMO upon the first attempt after a mean support of 11.9 ± 6.1 days, but the other 10 died due to overwhelming infection. Univariate analysis revealed no significant pre-ECMO risk factor for treatment failure but C-reactive protein concentration at the time of ECMO differed significantly among patients who did versus did not survive after ECMO. CONCLUSIONS ECMO as rescue therapy may be a final therapeutic option for OLT recipients with refractory pulmonary dysfunction who would otherwise die due to hypoxemia from severe pneumonia or adult respiratory distress syndrome.

De Novo Malignancies After Liver Transplantation: Incidence Comparison With the Korean Cancer Registry

PURPOSE De novo malignancy is not uncommon after liver transplantation (OLT). We have compared the incidence of novo malignancy following OLT with those among the general Korean population. METHODS Between January 1998 and December 2008, 1952 adult OLT were performed, including 1714 living donor and 238 deceased donor grafts whose medical records were retrospectively reviewed. RESULTS Among the 1952 patients, 44 (2.3%) showed de novo malignancies after a mean posttransplant period of 41 months. Among the 14 types of malignancy the most frequent was stomach cancer (n = 11; 25.0%), colorectal cancer (n = 9; 20.5%), breast cancer (n = 4; 9.1%), and thyroid cancer (n = 3; 6.8%). These patients underwent aggressive treatment, including surgery, chemotherapy, and radiotherapy, except for one patient with an aggressive primary liver cancer. Over a mean follow-up of 45 months after diagnosis of de novo malignancy, 13 patients (29.5%) died; the overall 3-year patient survival rate was 67.5%. The relative risk of malignancy following OLT was 7.7-fold higher in men and 7.3-fold higher in women than the Korean general population. CONCLUSIONS OLT recipients must be checked periodically for de novo malignancy throughout their lives, especially for cancers common in the general population.

ABO-Incompatible Adult Living Donor Liver Transplantation Under the Desensitization Protocol With Rituximab

ABO incompatibility is no longer considered a contraindication for adult living donor liver transplantation (ALDLT) due to various strategies to overcome the ABO blood group barrier. We report the largest single‐center experience of ABO‐incompatible (ABOi) ALDLT in 235 adult patients. The desensitization protocol included a single dose of rituximab and total plasma exchange. In addition, local graft infusion therapy, cyclophosphamide, or splenectomy was used for a certain time period, but these treatments were eventually discontinued due to adverse events. There were three cases (1.3%) of in‐hospital mortality. The cumulative 3‐year graft and patient survival rates were 89.2% and 92.3%, respectively, and were comparable to those of the ABO‐compatible group (n = 1301). Despite promising survival outcomes, 17 patients (7.2%) experienced antibody‐mediated rejection that manifested as diffuse intrahepatic biliary stricture; six cases required retransplantation, and three patients died. ABOi ALDLT is a feasible method for expanding a living liver donor pool, but the efficacy of the desensitization protocol in targeting B cell immunity should be optimized.

Reconstruction of inferior right hepatic veins in living donor liver transplantation using right liver grafts

Because revascularization of the inferior right hepatic vein (IRHV) is a major component of right liver graft (RLG) reconstruction, we assessed the surgical techniques and clinical outcomes of IRHV reconstruction so that we could formulate practical guidelines for standardized procedures. From July 2004 to February 2010, we performed separate IRHV reconstructions in 487 of 1142 adult RLG recipients (42.7%). These recipients included 364 patients with a natural single IRHV and 123 patients with multiple IRHVs; in the latter group, the IRHVs were unified by venoplasty, which enabled a single anastomosis. The 1‐year stenosis rates for the single‐vein and venoplasty groups were 23% and 18.9%, respectively, and the early stent insertion rates were 7.1% and 9.8%, respectively (P = 0.09). Late IRHV occlusion did not lead to graft dysfunction, and all large major IRHVs were patent. A morphometric analysis showed that IRHV stenosis was associated with IRHV stretching and an anastomotic level discrepancy. This led to refinements of the surgical techniques: IRHV orifices were shaped into funnels, and the IRHV anastomosis was accurately placed at the recipient inferior vena cava (IVC). In an ongoing prospective study of 35 patients, our funneling unification venoplasty resulted in only 1 episode (2.9%) of early IRHV stenosis requiring stenting at a median follow‐up of 8 months. The final configurations of the reconstructed IRHVs after funneling unification venoplasty and extensive IVC dissection were very similar to those of the native donor liver. In conclusion, we suggest that in combination with extensive recipient IVC dissection, funneling and unification venoplasty techniques are useful for securely reconstructing single or multiple IRHVs during the implantation of RLGs. Liver Transpl 18:238–247, 2012.

Standardization of Modified Right Lobe Grafts to Minimize Vascular Outflow Complications for Adult Living Donor Liver Transplantation

BACKGROUND After >2000 adult living donor liver transplants (LDLTs), we observed minimization of the complication rate using case-by-case modification of venous outflow reconstruction in right liver graft (RLG), standardization seeking intend to provide a hemodynamic- based, regeneration-compliant hepatic outflow reconstruction. METHODS We retrospectively examined 100 consecutive adult LDLT using modified RLG before and after application of RLG standardization to compare the 6-month incidences of vascular outflow complications. RESULT The right hepatic vein stenting rate for first 6 months was 5% in the customized group and 1% in the standardized group (P=.212). The middle hepatic vein stenting rate for first 6 months was 9% in the customized group and 4% in the standardized group (P=.373). The inferior right hepatic vein stenting rate for first 6 months was 12.8% in the customized group and 7.1% in the standardized group (P=.472). The overall 6-month patient survival rate was 94% in the customized group and 95% in the standardized group (P=.867). The overall incidence of significant RLG venous outflow complications was 19% in the customized group and 8% in the standardized group (P=.023). CONCLUSION Standardization as a universal graft model seemed to be more effective and feasible than conventional graft customization requiring individualized case-by-case modification.

Clinical Value of Preoperative Coronary Risk Assessment by Computed Tomographic Arteriography Prior to Adult Living Donor Liver Transplantation

PURPOSE Patients with advanced liver diseases are at increased risk of cardiovascular events, resulting in a higher incidence of cardiac complications following liver transplantation (OLT). We assessed the clinical value of computed tomographic coronary arteriography (CTCAG) as a routine preoperative cardiac evaluation test in adult patients scheduled for living donor OLT (LDLT). METHODS This single-center, prospective, observational study evaluated 247 adult patients being assessed for LDLT from April 2010 to March 2011. CTCAG was performed in patients with all-negative findings on routine cardiac workup, including thallium single photon emission computed tomography (SPECT). RESULTS Of the 247 patients evaluated, 27 (10.9%) showed abnormal findings on CTCAG, with 18 (7.3%) showing mild to moderate involvement of one vessel; 7 (2.8%), two-vessel; and 2 (0.8%), three-vessel involvement. Coronary artery calcification was identified in patients with significant coronary artery stenosis. No adverse events occurred after CTCAG. Noticeable hypotensive episodes during LDLT surgery occurred in 5% of patients, mostly related to massive bleeding or postperfusion syndrome. During the first 3 months after LDLT, 3% of patients showed stress cardiomyopathy, but all recovered with supportive care. CONCLUSIONS The poor general medical condition of LDLT candidates and the diagnostic accuracy of CTCAG suggest that this test should be included in the routine pretransplant cardiac workup, along with thallium SPECT, for these patients.