scholarly journals Influences of Anatomorphological Features of the Portal Venous System on Postsplenectomy Hemodynamic Characteristics in Patients With Portal Hypertension: A Computational Model-Based Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Tianqi Wang ◽  
Zunqiang Zhou ◽  
Fuyou Liang
Keyword(s):  
Spatial Distribution ◽  
Portal Hypertension ◽  
Splenic Vein ◽  
Anatomical Structure ◽  
Venous System ◽  
Geometrical Parameters ◽  
Inferior Mesenteric Vein ◽  
Portal Venous System ◽  
Imaging Data ◽  
Hemodynamic Characteristics

Splenectomy, as an effective surgery for relieving complications caused by portal hypertension, is often accompanied by a significantly increased incidence of postoperative thrombosis in the portal venous system (PVS). While the underlying mechanisms remain insufficiently understood, the marked changes in hemodynamic conditions in the PVS following splenectomy have been suggested to be a potential contributing factor. The aim of this study was to investigate the influences of the anatomorphological features of the PVS on hemodynamic characteristics before and after splenectomy, with emphasis on identifying the specific anatomorphological features that make postoperative hemodynamic conditions more clot-promoting. For this purpose, idealized computational hemodynamics models of the PVS were constructed based on general anatomical structures and population-averaged geometrical parameters of the PVS. In the models, we incorporated various anatomorphological variations to represent inter-patient variability. The analyses of hemodynamic data were focused on the spatial distribution of wall shear stress (WSS) and the area ratio of wall regions exposed to low WSS (ALS). Obtained results showed that preoperative hemodynamic conditions were comparable among different models in terms of space-averaged WSS and ALS (all were small) irrespective of the considerable differences in spatial distribution of WSS, whereas, the inter-model differences in ALS were significantly augmented after splenectomy, with the value of ALS reaching up to over 30% in some models, while being smaller than 15% in some other models. Postoperative ALS was mainly determined by the anatomical structure of the PVS, followed by some morphogeometrical parameters, such as the diameter and curvature of the splenic vein, and the distance between the inferior mesenteric vein and splenoportal junction. Relatively, the angles between tributary veins and trunk veins only had mild influences on ALS. In addition, a marked increase in blood viscosity was predicted after splenectomy, especially in regions with low WSS, which may play an additive role to low WSS in initiating thrombosis. These findings suggest that the anatomical structure and some morphogeometrical features of the PVS are important determinants of hemodynamic conditions following splenectomy, which may provide useful clues to assessing the risk of postsplenectomy thrombosis based on medical imaging data.

scholarly journals Percutaneous transhepatic treatment of a unique portal vein malformation with portal hypertension in a pediatric patient

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Paolo Marra ◽  
Ludovico Dulcetta ◽  
Claudia Pellegrinelli ◽  
Lorenzo D’Antiga ◽  
Sandro Sironi
Keyword(s):  
Portal Hypertension ◽  
Portal Vein ◽  
Variceal Bleeding ◽  
Umbilical Vein ◽  
Venous System ◽  
Portal Venous System ◽  
Vascular Abnormality ◽  
Non Invasive ◽  
Percutaneous Transhepatic Portography ◽  
Transhepatic Portography

Abstract Background Anomalies of the portal venous system can be congenital or acquired, the latter being related to spontaneous thrombosis or iatrogenic alterations such as complications of perinatal catheterization of the umbilical vein. These conditions can be clinically silent for years and then manifest abruptly causing severe clinical emergencies. Case presentation This case report describes the diagnosis and interventional management of a singular abnormality in the portal venous system of an 8-year-old female that led to severe portal hypertension and acute variceal bleeding. Peculiar imaging findings were not pathognomonic for any of the known congenital and acquired portal vein anomalies: absence of a normal extrahepatic portal vein; splenic and mesenteric veins merging into a dilated left gastric vein; presence of an aberrant mesenteric venous collateral with a stenotic connection with the intrahepatic right portal branch; and absence of porto-systemic shunt. The case was successfully managed with percutaneous transhepatic portography and angioplasty. Conclusions Prompt non-invasive imaging characterization allowed to understand the singular vascular abnormality and mini-invasive interventional radiology management resolved portal hypertension and variceal bleeding.

scholarly journals Splenic Vein Diameter is a Risk Factor for the Portal Venous System Thrombosis After Partial Splenic Artery Embolization

2021 ◽  
Author(s):  
Satoyuki Ogawa ◽  
Akira Yamamoto ◽  
Atsushi Jogo ◽  
Mariko M. Nakano ◽  
Ken Kageyama ◽  
...  
Keyword(s):  
Risk Factors ◽  
Computed Tomography ◽  
Splenic Artery ◽  
Splenic Vein ◽  
Venous System ◽  
Maximum Diameter ◽  
Portal Venous System ◽  
Characteristic Analysis ◽  
Artery Embolization ◽  
Splenic Artery Embolization

Abstract Purpose Portal venous system thrombosis is a complication of partial splenic artery embolization, and pre-treatment risk assessment is thus important. The purpose of this study was to identify the risk factors for portal venous system thrombosis after partial splenic artery embolization. Materials and methods We retrospectively analyzed 67 consecutive patients who underwent contrast-enhanced computed tomography before and after first partial splenic artery embolization between July 2007 and October 2018. As risk factors, we investigated age, sex, hematological data, liver function, steroid use, heparin use, and findings from pre- and post-treatment computed tomography. Uni- and multivariate analyses were performed to evaluate the relationship between thrombus appearance or growth and these factors. Values of p < 0.05 were considered significant. Results Partial splenic artery embolization was technically successful in all 67 patients. Nine patients showed appearance or growth of thrombus. Univariate analysis showed maximum diameter of the splenic vein before treatment (p = 0.0076), percentage of infarcted spleen (p = 0.017), and volume of infarcted spleen (p = 0.022) as significant risk factors. Multivariate analysis showed significant differences in maximum diameter of the splenic vein before treatment (p = 0.041) and percentage of infarcted spleen (p = 0.023). According to receiver operating characteristic analysis, cutoffs for maximum diameter of the splenic vein and percentage of infarcted spleen for distinguishing the appearance or growth of thrombus were 17 mm and 58.2%. Conclusion Large maximum diameter of the splenic vein before partial splenic artery embolization and high percentage of infarcted spleen after partial splenic artery embolization were identified as risk factors for portal venous system thrombosis. Level of Evidence Level 4, Case Series

scholarly journals Pharmacologic Prophylaxis of Portal Venous System Thrombosis after Splenectomy: A Meta-Analysis

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Xingshun Qi ◽  
Ming Bai ◽  
Xiaozhong Guo ◽  
Daiming Fan
Keyword(s):  
Portal Hypertension ◽  
Meta Analysis ◽  
Venous System ◽  
Cochrane Library ◽  
Portal Venous System ◽  
Hematological Diseases ◽  
Risk Of Bleeding ◽  
Significant Difference ◽  
Life Threatening ◽  
Pharmacologic Prophylaxis

Portal venous system thrombosis (PVST) is a life-threatening complication of splenectomy. A meta-analysis was conducted to explore the role of pharmacologic prophylaxis of PVST after splenectomy. Overall, 359 papers were initially identified via the PubMed, EMBASE, and Cochrane Library databases. Eight of them were eligible. The incidence of PVST after splenectomy was significantly lower in patients who received the preventive measures than in those who did not (odds ratio [OR]: 0.33, 95% confidence interval [CI]: 0.22–0.47,P<0.00001). Subgroup analyses demonstrated that the significant difference remained in studies including patients with portal hypertension (n=6), but not in those including patients with hematological diseases (n=2); the significant difference remained in studies using any type of prophylactic drugs (anticoagulants [n=6], thrombolytics [n=1], and prostaglandin E1 [n=1]); the significant difference remained in nonrandomized studies (n=5), but not in randomized studies (n=3). The risk of bleeding was similar between the two groups (OR: 0.65, 95% CI: 0.10–4.04,P=0.64). In conclusion, pharmacologic prophylaxis might decrease the incidence of PVST after splenectomy in patients with portal hypertension and did not increase the risk of bleeding. However, the effect of pharmacologic prophylaxis of PVST in patients with hematological diseases remained questioned.

scholarly journals Unilateral Giant Varicocele Mimicking Inguinal Hernia Resulting from Portosystemic Shunt without Evidence of Portal Hypertension: An Unusual Case Report

2013 ◽  
Vol 2013 ◽  
pp. 1-3 ◽  
Author(s):  
Muhammed Zahir ◽  
Hassan R. Al Muttairi ◽  
Surjya Prasad Upadhyay ◽  
Piyush N. Mallick
Keyword(s):  
Inguinal Hernia ◽  
Portal Hypertension ◽  
Portal Pressure ◽  
Portosystemic Shunt ◽  
Venous System ◽  
Portal Venous System ◽  
Rare Presentation ◽  
Testicular Vein ◽  
Pampiniform Plexus ◽  
Surgical History

Isolated giant varicocele has been reported with portal hypertension that results in abnormal communication between portal venous system and testicular vein venous system resulting in retrograde backflow of blood into the testicular venous system which leads to varicosity of the pampiniform plexuses. 65-year-old male with no past medical or surgical history presented to us with soft inguinoscrotal swelling that disappears on lying down mimicking inguinal hernia. Clinical examination revealed soft inguionoscrotal swelling that disappears on pressure. Ultrasonography revealed varicosity of pampiniform plexus, and CT angiography to trace the extent of the varicosity revealed abnormal communication of right testicular vein with superior mesenteric vein. There was no evidence of any portal hypertension; the cause of the portosystemic shunt remains obscure, and it might be a salvage pathway for increasing portal pressure. The case is noteworthy for its rare presentation and abnormal communication with portal venous system in the absence of evidence of portal hypertension.

scholarly journals Sequential CT arterioportography-arteriosplenography depicts individual haemodynamic changes in children with portal hypertension without cirrhosis

2020 ◽  
Vol 4 (1) ◽  
Author(s):  
Simone Hammer ◽  
Hans Jürgen Schlitt ◽  
Birgit Knoppke ◽  
Veronika Ingrid Huf ◽  
Walter Alexander Wohlgemuth ◽  
...  
Keyword(s):  
Portal Hypertension ◽  
Splenic Vein ◽  
Inferior Mesenteric Vein ◽  
Complete Evaluation ◽  
Mesenteric Vein ◽  
Institutional Review ◽  
Single Centre Study ◽  
Haemodynamic Changes ◽  
Retrograde Blood Flow ◽  
Flow Through

AbstractWe evaluated sequential computed tomography (CT) arterioportography-arteriosplenography for the assessment of venous pathways in children with portal hypertension without cirrhosis. Institutional Review Board approval was obtained for this retrospective, single-centre study. CT was performed after contrast application via catheters placed in the superior mesenteric artery (CT arterioportography) and the splenic artery (CT arteriosplenography) consecutively. Venous pathways in 22 children were evaluated. In all patients, the detailed haemodynamic consequences of portal hypertension could be characterised. The supply of varices at different locations could be assigned to the superior mesenteric vein or splenic vein system. Retrograde blood flow through the splenic vein and inferior mesenteric vein, portosystemic shunting, and patency of splanchnic veins were determined. CT arterioportography-arteriosplenography allowed a complete evaluation of individual haemodynamic pathways in children with portal hypertension.

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