Percutaneous angioplasty of portal vein stenosis that complicates liver transplantation: the mid-term therapeutic results

Endovascular Treatment of Venous Outflow and Portal Venous Complications After Liver Transplantation

Liver transplantation continues to rapidly evolve, and in 2020, 8906 orthotopic liver transplants were performed in the United States. As a technically complex surgery with multiple vascular anastomoses, stenosis and thrombosis of the venous anastomoses are among the recognized vascular complications. While rare, venous complications may be challenging to manage and can threaten the graft and the patient. In the last 20 years, endovascular approaches have been increasingly utilized to treat post-transplant venous complications. Herein, the evaluation and interventional treatment of post-transplant venous outflow complications, portal vein stenosis, portal vein thrombosis, and recurrent portal hypertension with transjugular intrahepatic portosystemic shunt (TIPS) are reviewed.

Vascular complications after liver transplantation: contemporary approaches to detection and treatment. A literature review

Vascular complications (VCs) after liver transplantation (LT) are rare but are one of the most dreaded conditions that can potentially lead to graft loss and recipient death. This paper has analyzed the international experience in the early diagnosis of various VCs that can develop following LT, as well as the optimal timing and methods of treatment of these complications.

Long-term outcome of primary percutaneous stent angioplasty for pediatric posttransplantation portal vein stenosis

This study aims to evaluate the long-term efficacy and reintervention rate after primary percutaneous portal vein stent angioplasty for portal vein stenosis (PVS) in pediatric liver transplantation (LT) recipients. From 2004 to 2020, a total of 470 pediatric LTs were performed in our center. All cases were screened for interventional PVS treatment and analyzed retrospectively. We identified 44 patients with 46 percutaneous angioplasties for posttransplantation PVS. The median interval from LT to percutaneous catheter intervention was 5 months (16 days-104 months) with a median follow-up (f/u) period after catheter intervention of 5.7 years (2-156 months). In 40 patients, an endovascular stent was placed as primary (n = 38) or secondary (n = 2) intervention. The median age at stent placement was 23 (6-179) months with a median weight of 10 kg (6-46 kg). Technical success and relief of PVS were achieved in all patients irrespective of age or weight. Adverse events occurred peri-interventionally in two patients and were resolved with standard care. All primary portal vein (PV) stents remained patent until the end of f/u. Reinterventions have been successfully performed in 10 patients for suspected or proven restenosis, resulting in a primary patency rate of 75% and an assisted patency rate of 25%. The median time to reintervention was 6.2 years (range 1-10 years). The need for reintervention was independent of age or weight at both transplantation and initial angioplasty as well as of additional risk factors due to portal hypertension. Percutaneous transhepatic PV stent angioplasty in children is safe and effective in all age groups, with excellent long-term patency. Primary stent angioplasty should be considered as first-line treatment for PVS after pediatric LT.

Percutaneous transhepatic interventional therapy of portal vein stenosis in paediatric liver transplantation: A systematic review of efficacy and safety

PURPOSE OF THE SYSTEMATIC REVIEW

To determine the efficacy and safety of percutaneous trans-hepatic balloon and/or stent angioplasty (PTA) in the management of portal vein (PV) stenosis following paediatric liver transplantation.

METHODS

Articles were included from a systematic search of Medline, Embase, Cochrane CENTRAL, ClinicalTrials.gov and International Clinical Trials Registry from inception to the 29th of August 2020.

RESULTS

There were 213 paediatric liver recipients who underwent PTA for PV stenosis in 19 included studies published between 1991 and 2019. Balloon angioplasty was the initial treatment in the majority (n = 153). Primary stent placement (n = 34) was performed for elastic recoil, intimal tears and PV kinks and rescue stent placement (n = 14) for recurrent PV stenosis following primary balloon angioplasty. The technical success was 97.6%-100% overall, 97.6%-100% for balloon-angioplasty-only and 100% for primary stenting. The clinical success was 50%-100% overall, 50%-100% for balloon-angioplasty-only and 100% for primary stenting. Long-term PV patency was 50%-100% overall, 37.5%-100% for balloon-angioplasty-only and 100% for primary stenting. Primary balloon angioplasty was successful in 78% of the cases. Of the recurrent PV stenoses, 9% resolved with stent placement and one required a meso-Rex shunt. There was one re-transplantation without stenting. The complication rate was 2.6% for balloon-angioplasty-only (bleeding, liver abscess, 2 PV thromboses) and 5.9% for primary stenting (bleeding, stent-fracture). There was no procedure-related mortality.

CONCLUSION

Percutaneous transhepatic balloon angioplasty may be the initial management of portal vein stenosis in paediatric liver recipients. Stent placement may be a primary option in selected cases and a reliable rescue option for recurrent portal vein stenosis following balloon-angioplasty-only.

Portal Vein Stent Placement in Anastomotic Stenosis After Deceased Donor Liver Transplantation: A Case Report

Vascular complications (VCs) after liver transplantation (LT) frequently result in graft and patient loss. The smaller vessels and the insufficient length for reconstruction in living donor LT and pediatric transplantation predispose patients to a higher incidence of VCs. Herein we present a case of portal vein stenosis (PVS) in an adult deceased donor LT recipient with portal vein thrombosis requiring extended thrombectomy at the time of LT. He presented with ascites 4 months after LT, was diagnosed with PVS, and was successfully treated with percutaneous transhepatic venoplasty and placement of a portal stent. This case highlights the importance of Doppler ultrasound as a screening modality for detection of VCs after LT and the pivotal role of endovascular repair as a first-line treatment for PVS.

Portal Vein Complications After Adult Living Donor Liver Transplantation: Time of Onset and Deformity Patterns Affect Long-Term Outcomes

Portal vein complications (PVCs) after adult living donor liver transplantation (LDLT) are potentially lethal. We categorized PVCs by the time of onset (early versus late, <1 month versus ≥1 month, respectively) and deformity patterns (portal vein stenosis [PVS], portal vein thrombosis [PVT], and portal vein occlusion [PVO]) to establish optimal treatment strategies. Overall, 35/322 (10.9%) recipients developed PVCs between 2000 and 2019. Pretransplant PVT (odds ratio [OR], 15.20; 95% confidence interval [CI], 3.70-62.40; P < 0.001) was the only independent risk factor for PVS. In contrast, male sex (OR, 5.57; 95% CI, 1.71-18.20; P = 0.004), pretransplant PVT (OR, 4.79; 95% CI, 1.64-14.00; P = 0.004), and splenectomy (OR, 3.24; 95% CI, 1.23-8.57; P = 0.018) were independent risk factors for PVT. PVS was successfully treated with interventional radiology regardless of its time of onset. On the other hand, late PVT and PVO had significantly lower treatment success rates (2/15, 13%) compared with those that occurred in the early period (10/11, 91%) despite aggressive intervention (P < 0.001). Deformity patterns had a significant impact on the 5-year cumulative incidence of graft loss as a result of PVC (PVO + Yerdel grades 2-4 PVT group [n = 16], 41% versus PVS + Yerdel grade 1 PVT group [n = 19], 0%; P = 0.02). In conclusion, late grades 2 to 4 PVT and PVO are refractory to treatment and associated with poor prognoses, whereas PVS has a good prognosis regardless of time of onset. A tailored approach according to the time of onset and deformity patterns of PVC is essential.

Safety and Efficacy of Endovascular Treatment of Portal Vein Stenosis in Liver Transplant Recipients: A Systematic Review

PURPOSE

To evaluate the efficacy of Angioplasty and Stent Placement for the treatment of Portal Vein Stenosis in Liver Transplant Recipients by performing a systematic review.

MATERIALS AND METHODS

The PubMed Database was extensively searched for articles describing Portal Vein Stenosis (PVS) as a complication in Liver Transplant (LT) patients. The initial database search yielded 488 unique records published in the PubMed Database, 19 of which were deemed to meet the inclusion criteria. Outcomes were separated into 2 groups (Group A included patients with primary angioplasty, Group B included patients with primary stent placement), and further subdivided into Adult and Pediatric populations.

RESULTS

Group A included a total of 282 LT patients with portal vein stenosis. The population was predominantly pediatric (n = 243). Group B included a total of 111 LT patients with portal vein stenosis. This population was predominantly adult (n = 66). Technical success was significantly higher in both Group B pediatric (100%) and adults (97%) compared to Group A (69.5%) and (66.7%) respectively. Re-stenosis rates were significantly lower in Group B pediatric group compared to Group A (2.3% vs 29.7%, χ² = 13.9; p < 0.001). Overall major (3.1%) and minor complications rates (1.5%) were low.

CONCLUSION

Primary stent placement appears to have higher technical success in both populations and lower re-stenosis rates for treatment of PVS in pediatric populations.

Neoadjuvant chemotherapy followed by total pancreatectomy with splenectomy and combined vascular resections after preoperative percutaneous transhepatic portal vein stent placement in locally advanced pancreatic cancer with portal vein total obliteration

Pancreatic cancer is one of the most lethal malignant diseases in gastrointestinal system that only about 15-20% of the patients are potential candidates for resection at diagnostic stage. However, with the advent of neoadjuvant chemotherapy and advancement of surgical skills, patients with locally advanced pancreatic cancer (LAPC), which were deemed initially unresectable, have undergone margin negative radical resection. Here, we present a case of a patient with LAPC who was previously treated with neoadjuvant FOLFIRINOX and underwent pancreaticoduodenectomy combined with vascular resection after preoperative percutaneous transhepatic portal vein stent placement to relieve of portal vein obliteration. The patient recovered without any complication and was discharged on day 8 postoperatively.

Portal Vein Stenting for Delayed Jejunal Varix Bleeding Associated with Portal Venous Occlusion after Hepatobiliary and Pancreatic Surgery

Objective

The study aimed to describe portal stenting for postoperative portal occlusion with delayed (≥ 3 months) variceal bleeding in the afferent jejunal loop.

Materials and Methods

Eleven consecutive patients (age range, 2–79 years; eight men and three women) who underwent portal stenting between April 2009 and December 2015 were included in the study. Preoperative medical history and the postoperative clinical course were reviewed. Characteristics of portal occlusion and details of procedures were also investigated. Technical success, treatment efficacy (defined as disappearance of jejunal varix on follow-up CT), and clinical success were analyzed. Primary stent patency rate was plotted using the Kaplan-Meier method.

Results

All patients underwent hepatobiliary-pancreatic cancer surgery except two children with liver transplantation for biliary atresia. Portal occlusion was caused by benign postoperative change (n = 6) and local tumor recurrence (n = 5). Variceal bleeding occurred at 27 months (4 to 72 months) and portal stenting was performed at 37 months (4 to 121 months), on average, postoperatively. Technical success, treatment efficacy, and clinical success rates were 90.9, 100, and 81.8%, respectively. The primary patency rate of portal stent was 88.9% during the mean follow-up period of 9 months. Neither procedure-related complication nor mortality occurred.

Conclusion

Interventional portal stenting is an effective treatment for delayed jejunal variceal bleeding due to portal occlusion after hepatobiliary-pancreatic surgery.

Therapeutic efficacy and stent patency of transhepatic portal vein stenting after surgery

AIM

To evaluate portal vein (PV) stenosis and stent patency after hepatobiliary and pancreatic surgery, using abdominal computed tomography (CT).

METHODS

Percutaneous portal venous stenting was attempted in 22 patients with significant PV stenosis (> 50%) - after hepatobiliary or pancreatic surgery - diagnosed by abdominal CT. Stents were placed in various stenotic lesions after percutaneous transhepatic portography. Pressure gradient across the stenotic segment was measured in 14 patients. Stents were placed when the pressure gradient across the stenotic segment was > 5 mmHg or PV stenosis was > 50%, as observed on transhepatic portography. Patients underwent follow-up abdominal CT and technical and clinical success, complications, and stent patency were evaluated.

RESULTS

Stent placement was successful in 21 patients (technical success rate: 95.5%). Stents were positioned through the main PV and superior mesenteric vein (n = 13), main PV (n = 2), right and main PV (n = 1), left and main PV (n = 4), or main PV and splenic vein (n = 1). Patients showed no complications after stent placement. The time between procedure and final follow-up CT was 41-761 d (mean: 374.5 d). Twenty stents remained patent during the entire follow-up. Stent obstruction - caused by invasion of the PV stent by a recurrent tumor - was observed in 1 patient in a follow-up CT performed after 155 d after the procedure. The cumulative stent patency rate was 95.7%. Small in-stent low-density areas were found in 11 (55%) patients; however, during successive follow-up CT, the extent of these areas had decreased.

CONCLUSION

Percutaneous transhepatic stent placement can be safe and effective in cases of PV stenosis after hepatobiliary and pancreatic surgery. Stents show excellent patency in follow-up abdominal CT, despite development of small in-stent low-density areas.

Two Unusual but Treatable Causes of Refractory Ascites After Liver Transplantation

Refractory ascites (RA) is thought to complicate the postoperative course of 5-7% (Nishida et al. in Am J Transplant. 6: 140-149, 2006; Gotthardt et al. in Ann Transplant. 18: 378-383, 2013) of liver transplant recipients. RA after liver transplantation is often a frustrating diagnostic dilemma with few good management options unless an obvious mechanical factor is identified. Supportive therapies often fail until a treatable precipitating cause is identified and removed. We describe two patients who developed RA following liver transplantation for primary sclerosing cholangitis, and hepatitis C and alcoholic liver disease, respectively. The cause for RA was hyperkinetic portal hypertension secondary to splenomegaly in the first case and a pancreatic AVM in the 2nd case. After failure of other interventions, surgical splenectomy resulted in immediate and durable resolution of the previously intractable ascites.

Percutaneous access via the recanalized paraumbilical vein for varix embolization in seven patients

Objective

To evaluate the feasibility of percutaneous access via the recanalized paraumbilical vein for varix embolization.

Materials and Methods

Between July 2008 and Jan 2014, percutaneous access via the recanalized paraumbilical vein for varix embolization was attempted in seven patients with variceal bleeding. Paraumbilical vein puncture was performed under ultrasonographic guidance, followed by introduction of a 5-Fr sheath. We retrospectively evaluated the technical feasibility, procedure-related complications, and clinical outcomes of each patient.

Results

Recanalized paraumbilical vein catheterization was performed successfully in all patients. Gastroesophageal varix embolization was performed in six patients, and umbilical varix embolization was performed in one patient. Embolic materials used are N-butyl cyanoacrylate (n = 6) and coil with N-butyl cyanoacrylate (n = 1). There were no procedure-related complications. One patient underwent repeated variceal embolization 6 hours after initial procedure via recanalized paraumbilical vein, due to rebleeding from gastric varix.

Conclusion

Percutaneous access via the paraumbilical vein for varix embolization is a simple alternative in patients with portal hypertension.

Long-term outcome of percutaneous transhepatic balloon angioplasty for portal vein stenosis after pediatric living donor liver transplantation: a single institute's experience

PURPOSE

To evaluate retrospectively the long-term outcomes of percutaneous transhepatic balloon angioplasty performed for portal vein stenosis (PVS) after pediatric living donor liver transplantation (LDLT).

MATERIALS AND METHODS

Between October 1997 and December 2013, of 527 pediatric patients (age < 18 y) who underwent LDLT in a single institution, 43 patients (19 boys, 24 girls; mean age, 4.1 y ± 4.1) were confirmed to have PVS at direct portography with or without manometry and underwent percutaneous interventions, including balloon angioplasty with or without stent placement. Technical success, clinical success, laboratory findings, manometry findings, patency rates, and major complications were evaluated. Follow-up periods after initial balloon angioplasty ranged from 5-169 months (mean, 119 mo).

RESULTS

Technical success was achieved in 65 of 66 sessions (98.5%) and in 42 of 43 patients (97.7%), and clinical success was achieved in 37 of 43 patients (86.0%). Platelet counts improved significantly. Of 32 patients undergoing manometry, 19 showed significant improvement of pressure gradient across the stenosis after percutaneous transhepatic balloon angioplasty. At 1, 3, 5, and 10 years after balloon angioplasty, the rates of primary patency were 83%, 78%, 76%, and 70%, and the rates of primary-assisted patency were 100%, 100%, 100%, and 96%. Two major complications subsequent to balloon angioplasty were noted: severe asthma attack and portal vein thrombosis.

CONCLUSIONS

Percutaneous transhepatic balloon angioplasty is a safe and effective treatment with long-term patency for PVS after pediatric LDLT.

Successful treatment by balloon angioplasty under portography for late-onset stenosis of portal vein after cadaveric liver transplantation

A 69-year-old woman, who underwent cadaveric liver transplantation for non-B, non-C liver cirrhosis with hepatocellular carcinoma in April 2009, was admitted to our hospital because of graft dysfunction. Enhanced computed tomography revealed stenosis of the left branch of the portal vein, obstruction of the right branch of the portal vein at porta hepatis, and esophagogastric varices. Balloon angioplasty of the left branch of the portal vein under transsuperior mesenteric venous portography was performed by minilaparotomy. After dilatation of the left branch of the portal vein, the narrow segment of the portal vein was dilated, which resulted in reduction of collateral circulation. At 7 days after balloon angioplasty, esophageal varices were improved. The patient made a satisfactory recovery, was discharged 8 days after balloon angioplasty, and remains well.

Portal interventions in liver transplant recipients

Portal vein interventions in liver transplant recipients represent a group of interventions in the management of several disease entities including portal vein stenosis, portal vein thrombosis, and recurrent liver cirrhosis with portal hypertension with and without gastric varices. The procedures performed in these patient populations include portal vein angioplasty with or without stent placement for portal vein stenosis, portal vein thrombolysis with or without stent placement for portal vein thrombosis, transjugular intrahepatic portosystemic shunts or splenic embolization for cirrhosis, and balloon-occluded retrograde transvenous obliteration for gastric varices. This article discusses these disease entities and the minimal invasive procedures used in their management.

Hepatofugal portal venous flow on Doppler sonography after liver transplantation. Analysis of presumed causes based on radiologic and pathologic features

OBJECTIVES

The purpose of this study was to categorize hepatofugal portal venous flow on Doppler sonography after liver transplantation and to investigate its clinical importance and presumed causes based on radiologic and pathologic findings.

METHODS

This retrospective study was approved by our Institutional Review Board, and the requirement for informed consent was waived. Examination of our database over 4 years revealed 30 patients in whom Doppler sonography showed hepatofugal portal venous flow during follow-up periods. We investigated its occurrence and clinical features, including radiologic and pathologic findings, and classified the possible causes into 5 types: A, systemic problems; B, gross vascular abnormalities correctable by intervention; C, specific cardiac problems; D, microscopic abnormalities of the graft; and E, miscellaneous. We classified the patterns of hepatofugal portal venous flow into continuous hepatofugal or hepatofugal-dominant to-and-fro flow and hepatopetal-dominant to-and-fro flow, and we investigated the relationship of the presumed causes and flow patterns with the clinical course.

RESULTS

The incidence of hepatofugal portal venous flow was 2.38%. The overall mortality rate was 26.67% (95% confidence interval, 11.1%-42.9%): all patients (n = 5) in group A, 1 in group C, and 2 in group D, died. Possible cause type B and a mainly hepatopetal flow pattern were good prognostic factors (P = .031 and .018, respectively).

CONCLUSIONS

Hepatofugal portal venous flow reflects diverse pathologic conditions after liver transplantation, and its clinical importance also differs depending on the cause.

Portal vein stenosis: a rare yet clinically important cause of delayed-onset ascites after adult deceased donor liver transplantation: two case reports

Vascular complications following liver transplantation are well documented. While complications involving the portal vein are less common than the hepatic artery, portal vein complications can lead to potentially life-threatening sequelae including graft loss. Portal vein stenosis is an infrequent complication following liver transplant. The majority of these complications are seen in living donor liver transplants and pediatric liver transplants. We present 2 cases of delayed onset portal vein stenosis in adult deceased donor liver transplantation (ADDLT). The first patient presented with refractory ascites twelve months after ADDLT. He was diagnosed and successfully treated with percutaneous transhepatic portovenography and venoplasty. The second patient had a history of irradiation to his portal bed in the setting of cholangiocarcinoma. He developed refractory ascites and esophageal variceal bleeding>2 years after ADDLT. He underwent percutaneous transhepatic portovenoplasty, but eventually required placement of a portal stent due to continued problems with recurrent ascites. These 2 cases highlight the importance of considering portal vein stenosis in the differential diagnosis of late-onset ascites following liver transplantation, especially if there have been any predisposing risk factors such as portal bed irradiation or prior splenectomy.

Diagnosis and treatment of late-onset portal vein stenosis after pediatric living-donor liver transplantation

PURPOSE

Portal vein stenosis is a relatively rare complication after living-donor liver transplantation, which sometimes leads to a life-threatening event owing to gastrointestinal bleeding or graft failure. This study sought to evaluate the diagnoses and management of late-onset portal vein stenosis in pediatric living-donor liver transplants.

MATERIALS AND METHODS

Since September 2001, we performed 123 living-donor liver transplant procedures in 120 children, among which 109 children with a functioning graft at 6 months after living-donor liver transplant are included in this analysis. Seven instances of portal vein stenosis were diagnosed and were analyzed retrospectively.

RESULTS

The median age of the children was 5.3 years, and the median body weight was 19.2 kg. Portal vein stenosis was diagnosed at 11.2±3.1 months after living-donor liver transplantation. Whereas 3 children were asymptomatic, splenomegaly and/or massive ascites were observed in the remaining 4. Additionally, platelet counts were below the normal limit in 4 children. All children were treated with transhepatic balloon dilatation except 1. Intraluminal stent placement was needed in 1 child owing to resistance of balloon dilatation. The mean pressure gradient decreased from 12.4 to 3.2 mmHg after successful treatment. We did not observe any treatment-related complications. Portal venous patency was maintained in all children during posttreatment follow-up of 43.2±20.4 months. There were no recurrences of portal vein stenosis. One child died; the remaining 6 children are alive with good graft function at 49.8±23.9 months of follow-up.

CONCLUSION

Although most portal vein stenosis is asymptomatic, splenomegaly and platelet counts are 2 important markers for portal vein stenosis. Early detection of portal vein stenosis with these 2 markers can lead to successful interventional percutaneous approaches and avoid graft loss.

Balloon-occluded retrograde transvenous obliteration for a portosystemic shunt after pediatric living-donor liver transplantation

Portosystemic shunts may cause steal phenomenon after liver transplantation, which can lead to graft loss without proper management. Portal vein stenosis is one of the causes for the occurrence of portosystemic shunts after liver transplantation. Recently, new interventional radiologic techniques have been developed in the field of liver transplantation. Balloon-occluded retrograde transvenous obliteration (B-RTO) is a novel interventional technique for gastric varices and portosystemic shunts and also is effective for increasing portal vein flow. We herein report a pediatric case of portal vein stenosis with a large shunt successfully treated with a combination of balloon dilatation and B-RTO. If enlarged collateral vessels cause steal phenomenon, then B-RTO should be considered as an additional therapy.

Local recurrence of pancreatic cancer after primary surgical intervention: how to deal with this devastating scenario?

The dismal prognosis of pancreatic cancer reflects into the increased recurrence rate, even after R0 pancreaticoduodenectomy. Although, conventional radiation-, chemo- or surgical therapy in much selected cases, seem to work out favorably long term, less invasive and non-toxic methods with more immediate results are always preferred, concerning the already aggravated status of this group of patients. We present hereby a comprehensive review of the literature concerning the treatment of recurrent pancreatic cancer based on the case of a patient who 20 months after a pancreaticoduodenectomy developed portal hypertension and symptomatic first degree esophageal, gastric and mesenteric varices, caused by the nearly complete splenic vein obstruction at the portal vein confluence. The varices were revascularized by a percutaneous transhepatic placement of an endovascular stent into the splenic vein, along with a sequent stereotactic body radiation therapy for the local tumor control. Thanks to the accuracy and safety of the present combined treatment, the patient one year later presents control of the disease and its complications. Our paper is the first in the international literature that tries to review all the treatment modalities available (surgical, adjuvant, neoadjuvant and palliative therapy) and their efficacy, concerning the locally recurrent pancreatic cancer; furthermore, we tried to analyze the application of the above mentioned combined therapeutic approach in similar cases, elucidating simultaneously all the questions that arise. The limited existing data in the international literature and the lack of randomized controlled trials make this effort difficult, but the physician should be aware after all of all the available and innovative treatment modalities, before he chooses one. Finally, we would like to emphasize the fact that not only the local control but also the management of the complications are important for a prolonged median survival and a better quality of life after all.

Doppler ultrasound evaluation of postoperative portal vein stenosis in adult living donor liver transplantation

AIM

To evaluate the postoperative portal vein stenosis (PVS) and the diagnostic efficiency of Doppler ultrasound (DUS) in adult living donor liver transplantation (ALDLT).

MATERIALS AND METHOD

From January 2007 to December 2008, 103 ALDLTs were performed and postoperatively followed by routine DUS. The morphologic narrowing at the anastomotic site (AS) of the PVS was analyzed. We calculated the PV stenotic ratio (SR) using the following formula: SR (%)=PRE-AS/PRE (PRE=pre-stenotic caliber). An SR>50% was defined as the critical point for PVS. We also calculated the velocity ratio (VR) between the AS and PRE, and set the significant VR as >3:1. Statistical analyses were carried out to determine clinical significance.

RESULTS

Using the definition of morphologic PVS by DUS, there were total 20 cases (19.4%) in this series with SR>50%, which included 17 cases with VR>3:1. Eight cases of severe PVS had a stenotic AS>5 mm and subsequently underwent interventional management. Doppler criteria of SR and VR values were elevated up to 75.8% and 7.5:1, respectively, in these treated cases. Two cases of severe PVS subsequently developed PV thrombosis. Intervention by balloon dilation and/or stenting was performed successfully in this PVS case.

CONCLUSION

DUS is the most convenient and efficient imaging modality to detect and follow postoperative PVS in ALDLT. The Doppler criteria of SR and VR are both sensitive but less specific. Cases of AS<5 mm require interventional management for good long-term graft survival.

Vascular stents in the management of portal venous complications in living donor liver transplantation

To evaluate the efficacy of stent placement in the treatment of portal vein (PV) stenosis or occlusion in living donor liver transplant (LDLT) recipients, 468 LDLT records were reviewed. Sixteen (10 PV occlusions and 6 stenoses) recipients (age range, 8 months-59 years) were referred for possible interventional angioplasty (dilatation and/or stent) procedures. Stent placement was attempted in all. The approaches used were percutaneous transhepatic (n = 10), percutaneous transsplenic (n = 4), and intraoperative (n = 2). Technical success was achieved in 11 of 16 patients (68.8%). The sizes of the stents used varied from 7 mm to 10 mm in diameter. In the five unsuccessful patients, long-term complete occlusion of the PV with cavernous transformation precluded catherterization. The mean follow-up was 12 months (range, 3-24). The PV stent patency rate was 90.9% (10/11). Rethrombosis and occlusion of the stent and PV occurred in a single recipient who had a cryoperserved vascular graft to reconstruct the PV during the LDLT operation. PV occlusion of >1 year with cavernous transformation seemed to be a factor causing technical failure. In conclusion, early treatment of PV stenosis and occlusion by stenting is an effective treatment in LDLT. Percutaneous transhepatic and transsplenic, and intraoperative techniques are effective approaches depending on the situation.

Management of venous stenosis in living donor liver transplant recipients

AIM: To retrospectively evaluate the management and outcome of venous obstruction after living donor liver transplantation (LDLT).

METHODS: From February 1999 to May 2009, 1 intraoperative hepatic vein (HV) tension induced HV obstruction and 5 postoperative HV anastomotic stenosis occurred in 6 adult male LDLT recipients. Postoperative portal vein (PV) anastomotic stenosis occurred in 1 pediatric left lobe LDLT. Patients ranged in age from 9 to 56 years (median, 44 years). An air balloon was used to correct the intraoperative HV tension. Emergent surgical reoperation, transjugular HV balloon dilatation with stent placement and transfemoral venous HV balloon dilatation was performed for HV stenosis on days 3, 15, 50, 55, and 270 after LDLT, respectively. Balloon dilatation followed with stent placement via superior mesenteric vein was performed for the pediatric PV stenosis 168 d after LDLT.

RESULTS: The intraoperative HV tension was corrected with an air balloon. The recipient who underwent emergent reoperation for hepatic stenosis died of hemorrhagic shock and renal failure 2 d later. HV balloon dilatation via the transjugular and transfemoral venous approach was technically successful in all patients. The patient with early-onset HV stenosis receiving transjugular balloon dilatation and stent placement on the 15th postoperative day left hospital 1 wk later and disappeared, while the patient receiving the same interventional procedures on the 50th postoperative day died of graft failure and renal failure 2 wk later. Two patients with late-onset HV stenosis receiving balloon dilatation have survived for 8 and 4 mo without recurrent stenosis and ascites, respectively. Balloon dilatation and stent placement via the superior mesenteric venous approach was technically successful in the pediatric left lobe LDLT, and this patient has survived for 9 mo without recurrent PV stenosis and ascites.

CONCLUSION: Intraoperative balloon placement, emergent reoperation, proper interventional balloon dilatation and stent placement can be effective as a way to manage hepatic and PV stenosis during and after LDLT.

Diagnosis and treatment of pediatric patients with late-onset portal vein stenosis after living donor liver transplantation

Portal vein stenosis (PVS) after living donor liver transplantation (LDLT) is a serious complication that can lead to graft failure. Few studies of the diagnosis and treatment of late-onset (> or = 3 months after liver transplantation) PVS have been reported. One hundred thirty-three pediatric (median age 7.6 years, range 1.3-26.8 years) LDLT recipients were studied. The patients were followed by Doppler ultrasound (every 3 months) and multidetector helical computed tomography (once a year). Twelve patients were diagnosed with late-onset PVS 0.5-6.9 years after LDLT. All cases were successfully treated with balloon dilatation. Five cases required multiple treatments. Early diagnosis of late-onset PVS and interventional radiology therapy treatment may prevent graft loss.

[Percutaneous transhepatic metallic stent placement for the treatment of post-transplantation portal vein stenosis]

Liver transplantation is a routinely used therapeutic choice in the treatment of end stage liver disease. Portal vein stenosis is a rare vascular complication after liver transplantation. We report the interventional radiological management of three cases of portal vein stenosis.

AIM

The surgical management of portal vein stenosis can be hazardous for the patient and the transplanted liver in the early post-transplantation period. In general, interventional radiological methods are tolerable for patients and can be safely performed with high success rate. The aim of this report is to analyze the feasibility, the risks and the efficacy of the percutaneous transhepatic self expanding metallic stent placement into the portal vein.

METHOD

Three of the 396 liver transplantations cases in Budapest developed significant portal vein stenosis. In these cases, ultrasound guided percutaneous transhepatic portal vein puncture with fine needle was performed. The tract was dilated with a coaxial dilator set, and an adequately sized sheath introducer was inserted into the liver parenchyma. Two nitinol and one stainless steel self expanding metallic stent were implanted at the stenotic portal vein anastomoses. The tract was embolized with gelfoam particles (1 case), or coils (1 case). In the third patient no tract embolization was performed.

RESULT

All treatments were technically successful, without minor or major complications. In two cases the amount of free abdominal fluid decreased significantly, and in the third case the esophageal varicosity regressed. The morphological success was documented with ultrasound and computed tomography examination. Two patients are alive and well after 10 and 39 months of follow up, while the third patient died after one month in multi organ failure.

CONCLUSION

Percutaneous transhepatic metallic stent placement for the treatment of post-transplantation portal vein stenosis is a safe and effective method.

Percutaneous portal venoplasty and stenting for anastomotic stenosis after liver transplantation

AIM: To review percutaneous transhepatic portal venoplasty and stenting (PTPVS) for portal vein anastomotic stenosis (PVAS) after liver transplantation (LT).

METHODS: From April 2004 to June 2008, 16 of 18 consecutive patients (11 male and 5 female; aged 17-66 years, mean age 40.4 years) underwent PTPVS for PVAS. PVAS occurred 2-10 mo after LT (mean 5.0 mo). Three asymptomatic patients were detected on routine screening color Doppler ultrasonography (CDUS). Fifteen patients who also had typical clinical signs of portal hypertension (PHT) were identified by contrast-enhanced computerized tomography (CT) or magnetic resonance imaging. All procedures were performed under local anesthesia. If there was a PVAS < 75%, the portal pressure was measured. Portal venoplasty was performed with an undersized balloon and slowly inflated. All stents were deployed immediately following the predilation. Follow-ups, including clinical course, stenosis recurrence and stent patency which were evaluated by CDUS and CT, were performed.

RESULTS: Technical success was achieved in all patients. No procedure-related complications occurred. Liver function was normalized gradually and the symptoms of PHT also improved following PTPVS. In 2 of 3 asymptomatic patients, portal venoplasty and stenting were not performed because of pressure gradients < 5 mmHg. They were observed with periodic CDUS or CT. PTPVS was performed in 16 patients. In 2 patients, the mean pressure gradients decreased from 15.5 mmHg to 3.0 mmHg. In the remaining 14 patients, a pressure gradient was not obtained because of > 75% stenosis and typical clinical signs of PHT. In a 51-year-old woman, who suffered from massive ascites and severe bilateral lower limb edema after secondary LT, PVAS complicated hepatic vein stenosis and inferior vena cava (IVC) stenosis. Before PTPVS, a self-expandable and a balloon-expandable metallic stent were deployed in the IVC and right hepatic vein respectively. The ascites and edema resolved gradually after treatment. The portosystemic collateral vessels resulting from PHT were visualized in 14 patients. Gastroesophageal varices became invisible on poststenting portography in 9 patients. In a 28-year-old man with hepatic encephalopathy, a pre-existing meso-caval shunt was detected due to visualization of IVC on portography. After stenting, contrast agents flowed mainly into IVC via the shunt and little flowed into the portal vein. A covered stent was deployed into the superior mesenteric vein to occlude the shunt. Portal hepatopetal flow was restored and the IVC became invisible. The patient recovered from hepatic encephalopathy. A balloon-expandable Palmaz stent was deployed into hepatic artery for anastomotic stenosis before PTPVS. Percutaneous transhepatic internal-external biliary drainage was performed in 2 patients with obstructive jaundice. Portal venous patency was maintained for 3.3-56.6 mo (mean 33.0 mo) and all patients remained asymptomatic.

CONCLUSION: With technical refinements, early detection and prompt treatment of complications, and advances in immunotherapy, excellent results can be achieved in LT.

Management of portal venous complications after liver transplantation

The postoperative vascular complications following liver transplantation, specifically portal venous complications, have been well documented. These complications, which include portal venous stenosis and thrombosis, can be potentially devastating and lead to graft failure. The interventional techniques in managing these complications are relatively new and have been developed only in the past 15 to 20 years. Additionally with the increasing numbers of split liver and living related transplants that are being performed, so has the incidence of portal venous complications increased. This article is a review of the current interventional techniques used in managing portal venous complications in the posttransplant patient. The topics covered include portal vein angioplasty, stenting, and thrombolysis with a description of the variety of techniques used to perform these procedures. The review also covers management of portal hypertension by creating a transjugular intrahepatic portosystemic shunt (TIPS).

Liver transplantation: vascular complications

Transplantation has become the method of choice for treatment of patients with irreversible severe liver dysfunction. Vascular thrombosis or stenosis, biliary obstruction, hemorrhage, posttransplantation neoplasm, and rejection are some of the most common potential complications. Most complications cause significant morbidity and mortality after liver transplantation. The appearance of vascular complications in posttransplantation patients is illustrated in this article.

Transileocolic venous balloon dilatation for the management of primary and recurrent portal venous stenosis after living donor liver transplantation in children

Portal venous stenosis is relatively a rare complication after liver transplantation in children and it sometimes leads to life threatening event due to gastrointestinal bleeding or graft failure. Recently, balloon dilatation has been widely accepted as a treatment of choice for the management of portal venous stenosis. The purpose of this study was to evaluate the feasibility of transileocolic venous balloon dilatation for the management of primary and recurrent portal venous stenosis after living donor liver transplantation (LDLT) in children. The records of 57 pediatric liver transplants were retrospectively reviewed. Nine patients (15.8%) with portal venous stenosis were identified. Seven symptomatic children with portal venous stenosis underwent balloon dilatation. Two approaches were employed for balloon dilatation; the transileocolic venous approach and the percutaneous transhepatic approach. In patients with recurrent stenosis, careful follow-up was carried out while they were asymptomatic. Twelve balloon dilatations were performed in seven children with primary or recurrent portal venous stenoses. The initial technical success rate was 91.7% (11/12), while 6 out of 12 (50.0%) procedures resulted in recurrent stenosis. Five out of six recurrent stenoses required repeated balloon dilatation. The clinical success rate of balloon dilatation in our study was 85.7% (6/7). Other than recurrent stenosis, two procedure-related complications occurred. In conclusion, transileocolic venous balloon dilatation was a safe and effective procedure for portal venous stenosis after LDLT in children.

Stent Placement for the Treatment of Portal Vein Stenosis or Occlusion in Pediatric Liver Transplant Recipients

PURPOSE

To evaluate the efficacy of stent placement for the treatment of portal vein (PV) stenosis or occlusion in pediatric liver transplant recipients.

MATERIALS AND METHODS

Written informed consent was obtained from a legal guardian, and our institutional review board approved this study. Percutaneous (n = 10) or intraoperative (n = 2) stent placement was attempted in 12 pediatric recipients (age range, 6-102 months) via the percutaneous transhepatic or inferior mesenteric vein route. Stents 6-10 mm in diameter were placed. Technical and clinical success, complications, and patency of the PV were retrospectively analyzed.

RESULTS

Technical success was achieved in 10 of 12 patients (83%) and clinical success was achieved in eight patients (67%). Eight of the 10 patients in whom technical success was achieved (80%) remained healthy with a patent PV during the 10-58-month clinical follow-up period. One patient with technical success died of acute rejection without recurrent PV complications and another died of acute rejection after stent replacement as a result of an hourglass deformity of a deployed stent with partial thrombosis. No major procedural complications occurred.

CONCLUSIONS

Based on this study in a relatively small number of patients, PV stent placement seems to be a safe and effective method for the treatment of posttransplantation PV stenosis or occlusion in pediatric patients.

Early posttransplantation portal vein stenosis following living donor liver transplantation: percutaneous transhepatic primary stent placement

Surgical treatments have usually been preferred for early posttransplantation portal inflow abnormalities. However, these treatments are limited due to their technical difficulty and multiple complicating factors. The present study reports the efficacy and safety of percutaneous transhepatic primary stent placement to treat early posttransplantation (<or=1 month) portal vein (PV) stenosis. A total of 9 patients who had undergone living donor liver transplantation underwent percutaneous stent placement to treat PV stenosis. The average interval between liver transplantation and stent placement was 13 +/- 10 days. Technical and clinical success was obtained in 7 (77.8%) of the 9 patients. Of the 7 patients with clinical success, 1 died of cerebral hemorrhage within 1 month following stent placement. The remaining 6 patients have remained healthy and without recurrence of PV stenosis until the time this manuscript was completed, and follow-up Doppler ultrasound (US) or computed tomography (CT) obtained 66.6 +/- 16.1 months after stent placement revealed patent portal inflow in all of these 6 patients. Major complications occurred in 3 patients, i.e., 2 cases of hemoperitoneum caused by blood oozing from a transhepatic tract of the liver grafts and 1 case of intrahepatic pseudoaneurysm. These complications were successfully treated using surgical ligation (n = 2) or transarterial coil embolization (n = 1). In conclusion, although we did experience some procedural complications, the percutaneous transhepatic primary stent placements in our study showed acceptable technical and clinical results for treating early posttransplantation PV stenosis. In addition, long-term PV patency following stent placement was excellent. However, additional experience and further studies will be needed to verify the usefulness of primary stent placement in the early posttransplantation period.

Percutaneous intravascular stents for treatment of portal venous stenosis after liver transplantation: midterm results

Portal vein stenosis after liver transplantation is a relatively uncommon vascular complication that may result in graft loss if not promptly treated. The purpose of this study was to evaluate the midterm result of the use of intravascular stents for portal vein stenosis after liver transplantation. From April 2004 to September 2005, percutaneous transhepatic balloon dilation with stent deployment was performed in nine cases. Varices were embolized with stainless steel coils in two cases. No procedure-related complication occurred. Portal venous patency was maintained in all nine patients from 6 to 19 months (mean 10 months). In conclusion, an intravascular stent is an effective treatment for the portal vein stenosis after liver transplantation with excellent midterm patency.