Portal vein arterialization in 25 liver transplant recipients:A Latin American single-center experience

BACKGROUND Portal vein arterialization(PVA)has been used in liver transplantation(LT)to maximize oxygen delivery when arterial circulation is compromised or has been used as an alternative reperfusion technique for complex portal vein thrombosis(PVT).The effect of PVA on portal perfusion and primary graft dysfunction(PGD)has not been assessed.All patients receiving PVA and LT at the Fundacion Santa Fe de Bogota between 2011 and 2022 were analyzed.To account for the time-sensitive effects of graft perfusion,patients were classified into two groups:prereperfusion(pre-PVA),if the arterioportal anastomosis was performed before graft revascularization,and postreperfusion(post-PVA),if PVA was performed afterward.The pre-PVA rationale contemplated poor portal hemodynamics,severe vascular steal,or PVT.Post-PVA was considered if graft hypoperfusion became evident.Conservative interventions were attempted before PVA.

Effects of partial portal vein arterialization on the hilar bile duct in a rat model

BACKGROUND: Liver revascularization is frequently required during the enlarged radical operation for hilar cholangio carcinoma involving the hepatic artery. Researchers have carried out a number of experiments applying partial porta vein arterialization (PVA) in clinical practice. In this study we aimed to establish a theoretical basis for clinical application o partial PVA and to investigate the effects of partial PVA on ra hilar bile duct and hepatic functions. METHODS: Thirty rats were randomly and equally assigned into 3 groups: control (group A), hepatic artery ligation+bile duct recanalization (group B), and partial PVA+bile duc recanalization (group C). Proliferation and apoptosis o rat hilar bile duct epithelial cells, arteriolar counts of the peribiliary plexus (PBP) of the bile duct wall, changes in serum biochemistry, and pathologic changes in the bile duc were assessed 1 month after operation. RESULTS: The proliferation of hilar bile duct epithelial cells in group B was greater than in groups A and C (P<0.01). No apoptotic hilar bile duct epithelial cells were detected in any of the groups. The PBP arteriolar counts of the hilar bile duc wall were similar in groups A and C (P>0.05), but the coun was lower in group B than in group A (P<0.01). No statistically significant differences in alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and albumin were found in the 3 groups. The gamma-glutamyltransferase value was higher in group B than in groups A and C (P<0.01) The hepatic tissues of groups A and C showed no significan abnormality. Chronic inflammatory changes in the hilar bile duct walls were observed only in group B. CONCLUSION: Partial PVA can restore the arterial blood supply of the hilar bile duct and significantly extenuate the injury to hilar bile duct epithelial cells resulting from hepatic artery ligation.

Portal vein arterialization promotes liver regeneration after extended partial hepatectomy in a rat model

In the current study, we sought to establish a novel rat model of portal vein artefialization （PVA） and evaluate its impact on liver regeneration after extended partial hepatectomy （PH）. A total of 105 Sprague-Dawley rats were randomly assigned to three groups： 68% hepatectomy （the PH group）, portal arterialization after 68% hepatectomy （the PVA group）, and fight nephrectomy only （the control group）. Liver regeneration rate （LRR）, 5-bromo-2-deoxyuridine （BrdU） labeling index, and liver functions were assessed on postoperative day 2, 7, 14 and 28. The 28-day survival rates were compared among the three groups. The 28-day survival rates were similar in all groups （P = 0.331）, and the anastomotic patency was 100%. The LRR in the PVA group was significantly higher than that of the PH group within postoperative 14 days （P 〈 0.05）. The PVA and PH group had increased serum alanine aminotransferase levels （232 ±61 U/L and 212 ±53 U/L, respectively） compared with the control group （101 ±13 U/L） on postoperative day 2, whereas from postoperative day 7 to day 28 there were no differences among the three groups. Serum albumin values were higher after the PVA procedure within postoperative day 14, which gradually became comparable on postoperative day 28 among the three groups. The peaks of BrdU labeling index appeared on postoperative day 2 in all rats, and the PVA procedure was associated with increased BrdU labeling index from postoperative day 7 to 28. The 28-day survival of the PVA rats was comparable. Our findings demonstrate that the PVA procedure utilizing portal vein trunk-renal artery microvascular reconstruction promotes remnant liver regeneration and confers beneficial effects on maintaining and even optimizing liver function after extended partial hepatectomy in rats.

Portal vein arterialization technique for liver transplantation patients

Liver transplantations were performed on two patients with hepatic failure caused by liver cirrhosis.Hard obsolete thrombi and portal venous sclerosis were observed in the major portal veins of both patients.The arteria colica media of one recipient and the portal vein of the donor were anastomosed end-to-end.The hepatic artery of the first donor was anastomosed end-to end with the gastroduodenal artery of the first recipient;meanwhile,the portal vein of the second donor was simultaneously anastomosed end-to-end with the common hepatic artery of the second recipient.The blood flow of the portal vein,the perfusion of the donor liver and liver function were satisfactory after surgery.Portal vein arterialization might be an effective treatment for patients whose portal vein reconstruction was difficult.

Partial portal vein arterialization using right gastroepiploic artery:A novel solution for portal hypoperfusion

To the Editor:Establishing dual arterial and portal inflow is essential for liver transplantation[1].Inadequate portal inflow compromises graft function and graft survival[2].Portal hypoperfusion is usually a consequence of spontaneous portosystemic shunt,ligation of which

Treatment controversies in a rare case of a simultaneous branch retinal artery and vein occlusion secondary to hyperhomocysteinemia and hypertension

Dear Editor,Combined vascular occlusions involving retinal arteries and veins have been reported in the past. Combined occlusion of the central retinal vein （CRVO） and artery （CRAO）is well described;. Cilioretinal artery occlusion along with CRVO is frequently reported and is well characterized;.

From portal to splanchnic venous thrombosis:What surgeons should bear in mind

The present study aims to review the evolution of surgical management of portal(PVT) and splanch-nic venous thrombosis(SVT) in the context of liver transplantation over the last 5 decades. PVT is more commonly managed by endovenous thrombectomy, while SVT requires more complex technical expedients. Several surgical techniques have been proposed, such as extensive eversion thrombectomy, anastomosis to collateral veins, reno-portal anastomosis, cavo-portal hemi-transposition, portal arterialization and combined liver-intestinal transplantation. In order to achieve satisfactory outcomes, careful planning of the surgical strategy is mandatory. The excellent results that are ob-tained nowadays confirm that, even extended, splanch-nic thrombosis is no longer an absolute contraindication for liver transplantation. Patients with advanced portal thrombosis may preferentially be referred to specialized centres, in which complex vascular approaches and even multivisceral transplantation are performed.

Outflow reconstruction with arterial patch in domino liver transplantation: a new technical option

Domino liver transplantation（LT）, using livers from familial amyloidotic polyneuropathy（FAP） patients, is a well described technique useful to expand donor pool. One of the main difficulties of this type of LT arises from the necessity to share the vascular pedicles between the graft and the donor. The most important challenge resides in restoring a proper hepatic venous outflow in the FAP-liver recipient.This is specially challenging when using the piggy-back technique, because the hepatic stumps may be too short. To overcome this issue, surgeons explored several techniques using different types of venous grafts. We describe a new technical option by using an arterial graft from the deceased donor. By using both iliac arteries a long graft is created and sutured as needed to the hepatic vein stump. We describe herein this new technique employed in a domino liver recipient who underwent retransplantation for ischemic cholangitis. The procedure was performed using the piggy-back technique; the venous stump of the FAP liver was reconstructed with the arterial graft. The patient had uneventful postoperative and mid-term hepatic function, and anastomosis was patent 24 months after LT.

ANGIOGRAPHIC STUDY ON THE PATENCY OF SINGLE VERSUS SEQUENTIAL VENOUS GRAFT BEFORE REDO CORONARY ARTERY BYPASS SURGERY

Objective:To compare the long-term patency and longevity of the single and sequential ve-nous graft.Methods:The coronary arterial angiographic data for 300 redo coronary bypass grafting(CABG) were collected.Among them 106 cases had both single(159) and sequential(118) grafts.Results:The oc-clusive and narrowness rate for the single grafts versus sequential grafts were:1 year,2% vs 2%;5 years,3% vs 4%;10years,18% vs 19%;15 years,60% vs 68%;and 23 years,76% vs 81% ,respectively.The differences were not significant in general.Conclusion:Sequential anastomosis itself does not has any adverse affects on short-term and long-term patency of the venous graft and its longevity in CABG operations in general.

Effects of partial portal vein arterialization on liver regeneration after hepatectomy in minipigs with obstructive jaundice

Background Hilar cholangiocarcinoma is a malignant tumor that is difficult to cure. The aim of this study was to observe the effects of flow-controlled partial portal vein arterializations （PPVA） on liver regeneration after hepatectomy in minipigs with chronic obstructive jaundice. Methods Eight minipigs were made into chronic obstructive jaundice models. United semi-hepatectomy, which imitates extended radical surgery for treatment of hilar cholangiocarcinoma, was then performed. The eight minipigs were randomly divided into groups A and B （n=4 minipigs each）. PPVA was performed in Group A but not in Group B. The effects of flow-controlled PPVA on live regeneration after hepatectomy were observed for 30 days after hepatectomy. Results The portal vein PO2 at the immediate time point and on postoperative day 30 was higher in Group A （（47.33±2.43） and （48.50±4.44） mmHg） than in Group B （（35.38±4.06） and （35.55±2.55） mmHg respectively, all P 〈0.01）. The mitotic index of liver cells on postoperative days 14 and 21 was higher in Group A （12.55%±2.85% and 15.25%±1.99% respectively） than in Group B （6.85%±2.10% and 11.88%±1.15% respectively, all P 〈0.05）. The regeneration rate of residual liver on postoperative days 14 and 21 was higher in Group A （24.56%±6.15% and 70.63%±9.83% respectively） than in Group B （11.96%±5.43% and 44.92%±7.42% respectively, P 〈0.05 and P 〈0.01 respectively）.Conclusion Flow-controlled PPVA can promote liver regeneration after hepatectomy and prevent liver failure in minipigs with chronic obstructive jaundice.

Observation on Efficacy of Puerarin in Treating Diabetic Retinopathy

Objective: Using the principle of promoting blood circulation to remove stasis to observe central retinal arterial and venous blood flow indexes, and hemorrheology of diabetic retinopathy patients with puerarin. Methods: Thirty patients with diabetic retinopathy were randomly divided into the treated group (n=15) and the control group (n=15). The treated group was given puerarin 400 mg per day intravenously dripping. The control group was given Mikebao 500 μg intramuscularly, once per day. Both groups were treated for 3 consecutive weeks as one treatment course. Two courses later, hemorrheologic parameters, central retinal arterial and venous blood flow indexes were observed. Results: Comparison before and after treatment showed red blood cell aggregation index, the whole blood viscosity rate, plasma viscosity rate, fibrinogen and erythrocyte sedimentation rate, have all improved obviously ( P <0.05, P <0.01). Compared with the control group, there was significant difference ( P <0.05, P <0.01). With the treated group before and after treatment, the peak systolic velocity (PSV) of central retinal artery, their end diastolic volume, the acceleration, the central retinal venous reflux velocity have improved respectively. Naked eye visions were also improved, compared with the control group, the difference was significant ( P <0.01). Conclusion: Puerarin could reduce blood viscosity, improve microcirculation, and play a positive therapeutic role in diabetic retinopathy.