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Critical Care (London, England) May 2022Venous return is the flow of blood from the systemic venous network towards the right heart. At steady state, venous return equals cardiac output, as the venous and... (Review)
Review
Venous return is the flow of blood from the systemic venous network towards the right heart. At steady state, venous return equals cardiac output, as the venous and arterial systems operate in series. However, unlike the arterial one, the venous network is a capacitive system with a high compliance. It includes a part of unstressed blood, which is a reservoir that can be recruited via sympathetic endogenous or exogenous stimulation. Guyton's model describes the three determinants of venous return: the mean systemic filling pressure, the right atrial pressure and the resistance to venous return. Recently, new methods have been developed to explore such determinants at the bedside. In this narrative review, after a reminder about Guyton's model and current methods used to investigate it, we emphasize how Guyton's physiology helps understand the effects on cardiac output of common treatments used in critically ill patients.
Topics: Blood Pressure; Cardiac Output; Heart; Humans; Models, Cardiovascular; Vascular Resistance; Veins
PubMed: 35610620
DOI: 10.1186/s13054-022-04024-x -
RoFo : Fortschritte Auf Dem Gebiete Der... Feb 2022Portal vein thrombosis (PVT) is a rare but severe entity that can cause clinically significant sequela such as worsening portal hypertension or mesenteric ischemia.... (Review)
Review
BACKGROUND
Portal vein thrombosis (PVT) is a rare but severe entity that can cause clinically significant sequela such as worsening portal hypertension or mesenteric ischemia. Those cases refractory to medical management may be referred for endovascular intervention. Several technical considerations have been described in the literature, but a cohesive comparison of these multiple techniques is lacking.
METHODS
The purpose of this article is to review the diagnosis and endovascular management of PVT, including areas in which further research is warranted.
RESULTS
Cases of PVT can be readily diagnosed using ultrasound, computed tomography, or magnetic resonance imaging. Treatment often begins with systemic anticoagulation and endovascular interventions may be used in selected cases. Determining the optimal approach to accessing the portal venous system depends on the underlying disease and chronicity of the thrombus and the degree of occlusion. Once access to the portal venous system is established, catheter-directed therapy may be performed to achieve recanalization.
CONCLUSION
Despite the heterogeneity in patient presentation, cases of PVT can be readily diagnosed across several imaging modalities. Strategizing interventional approaches involves evaluation of the underlying disease and the chronicity of the thrombus.
KEY POINTS
· This review will enable interventionalists to establish a framework for treating portal vein thrombosis by identifying patient risk factors and thrombus characteristics that determine patient management.. · The unique risks and benefits for transhepatic, transsplenic, and transmesenteric approaches for establishing portal venous access will be discussed.. · Advantages and complications of thrombolysis, thrombectomy, and transjugular intrahepatic portosystemic shunt creation for treating portal vein thrombosis will be reviewed in detail based on our extensive institutional experience..
CITATION FORMAT
· Ju C, Li X, Gadani S et al. Portal Vein Thrombosis: Diagnosis and Endovascular Management. Fortschr Röntgenstr 2022; 194: 169 - 180.
Topics: Endovascular Procedures; Humans; Portal Vein; Portasystemic Shunt, Transjugular Intrahepatic; Thrombosis; Treatment Outcome
PubMed: 34649289
DOI: 10.1055/a-1642-0990 -
European Journal of Pediatrics Mar 2018Congenital portosystemic venous shunts are rare developmental anomalies resulting in diversion of portal flow to the systemic circulation and have been divided into... (Review)
Review
UNLABELLED
Congenital portosystemic venous shunts are rare developmental anomalies resulting in diversion of portal flow to the systemic circulation and have been divided into extra- and intrahepatic shunts. They occur during liver and systemic venous vascular embryogenesis and are associated with other congenital abnormalities. They carry a higher risk of benign and malignant liver tumors and, if left untreated, can result in significant medical complications including systemic encephalopathy and pulmonary hypertension.
CONCLUSION
This article reviews the various types of congenital portosystemic shunts and their anatomy, pathogenesis, symptomatology, and timing and options of treatment. What is Known: • The natural history and basic management of this rare congenital anomaly are presented. What is New: • This paper is a comprehensive review; highlights important topics in pathogenesis, clinical symptomatology, and treatment options; and proposes an algorithm in the management of congenital portosystemic shunt disease in order to provide a clear idea to a pediatrician. An effort has been made to emphasize the indications for treatment in the children population and link to the adult group by discussing the consequences of lack of treatment or delayed diagnosis.
Topics: Abnormalities, Multiple; Endovascular Procedures; Hepatectomy; Humans; Ligation; Liver Transplantation; Portal Vein; Vascular Malformations
PubMed: 29243189
DOI: 10.1007/s00431-017-3058-x -
Journal of Vascular Surgery Jan 2015After the creation of an autogenous lower extremity bypass graft, the vein must undergo a series of dynamic structural changes to stabilize the arterial hemodynamic... (Review)
Review
After the creation of an autogenous lower extremity bypass graft, the vein must undergo a series of dynamic structural changes to stabilize the arterial hemodynamic forces. These changes, which are commonly referred to as remodeling, include an inflammatory response, the development of a neointima, matrix turnover, and cellular proliferation and apoptosis. The sum total of these processes results in dramatic alterations in the physical and biomechanical attributes of the arterialized vein. The most clinically obvious and easily measured of these is lumen remodeling of the graft. However, although somewhat less precise, wall thickness, matrix composition, and endothelial changes can be measured in vivo within the healing vein graft. Recent translational work has demonstrated the clinical relevance of remodeling as it relates to vein graft patency and the systemic factors influencing it. By correlating histologic and molecular changes in the vein, insights into potential therapeutic strategies to prevent bypass failure and areas for future investigation are explored.
Topics: Animals; Graft Occlusion, Vascular; Hemodynamics; Humans; Hyperplasia; Ischemia; Lower Extremity; Neointima; Risk Factors; Stress, Mechanical; Time Factors; Treatment Failure; Vascular Grafting; Vascular Remodeling; Veins; Wound Healing
PubMed: 24095042
DOI: 10.1016/j.jvs.2013.08.019 -
World Journal of Gastroenterology Sep 2016Portal biliopathy refers to cholangiographic abnormalities which occur in patients with portal cavernoma. These changes occur as a result of pressure on bile ducts from... (Review)
Review
Portal biliopathy refers to cholangiographic abnormalities which occur in patients with portal cavernoma. These changes occur as a result of pressure on bile ducts from bridging tortuous paracholedochal, epicholedochal and cholecystic veins. Bile duct ischemia may occur due prolonged venous pressure effect or result from insufficient blood supply. In addition, encasement of ducts may occur due fibrotic cavernoma. Majority of patients are asymptomatic. Portal biliopathy is a progressive disease and patients who have long standing disease and more severe bile duct abnormalities present with recurrent episodes of biliary pain, cholangitis and cholestasis. Serum chemistry, ultrasound with color Doppler imaging, magnetic resonance imaging with magnetic resonance cholangiopancreatography and magnetic resonance portovenography are modalities of choice for evaluation of portal biliopathy. Endoscopic retrograde cholangiography being an invasive procedure is indicated for endotherapy only. Management of portal biliopathy is done in a stepwise manner. First, endotherapy is done for dilation of biliary strictures, placement of biliary stents to facilitate drainage and removal of bile duct calculi. Next portal venous pressure is reduced by formation of surgical porto-systemic shunt or transjugular intrahepatic portosystemic shunt. This causes significant resolution of biliary changes. Patients who persist with biliary symptoms and bile duct changes may benefit from surgical biliary drainage procedures (hepaticojejunostomy or choledechoduodenostomy).
Topics: Bile Ducts; Biliary Tract; Cholangiography; Cholangiopancreatography, Endoscopic Retrograde; Cholangitis; Cholestasis; Gallbladder Diseases; Humans; Hypertension, Portal; Ischemia; Liver; Portal Pressure; Portal Vein; Portasystemic Shunt, Surgical; Stents
PubMed: 27672292
DOI: 10.3748/wjg.v22.i35.7973 -
Phlebology Dec 2020
Topics: Chronic Disease; Concept Formation; Humans; Veins; Venous Insufficiency
PubMed: 32525447
DOI: 10.1177/0268355520932371 -
Journal of Vascular Surgery. Venous and... Oct 2016This review explores the current literature on the natural history, diagnosis, and management of mesenteric venous thrombosis (MVT) in the modern era. (Review)
Review
OBJECTIVE
This review explores the current literature on the natural history, diagnosis, and management of mesenteric venous thrombosis (MVT) in the modern era.
METHODS
A review of the contemporary literature from 1997 to 2016 on MVT and its pathogenesis, diagnosis, and treatment was performed.
RESULTS
MVT is an insidious and lethal disease associated with acute mesenteric ischemia. The prevalence of MVT has increased sharply during the past two decades commensurate with an increase in radiographic imaging for abdominal complaints. The optimal treatment of and approach to MVT is controversial, given the poorly understood natural history of this rare disease. Both endovascular and open surgical strategies in addition to systemic anticoagulation have been used as adjuncts to treat MVT with limited success. Despite advances in treatment, mortality associated with MVT is still high. Furthermore, recent studies have shown that failure to recanalize the portomesenteric venous system leads to an increased risk for development of sequelae of portal hypertension.
CONCLUSIONS
MVT is a challenging disease to treat, given the difficulty in establishing a prompt initial diagnosis and the inability to reliably monitor patients for evidence of impending bowel infarction. Careful selection of patients for endovascular, open, or hybrid approaches is key to achieving improved outcomes. However, the paucity of prospective data and our evolving understanding of the natural history of MVT make consensus treatment strategies difficult to ascertain.
Topics: Acute Disease; Humans; Mesenteric Ischemia; Mesenteric Vascular Occlusion; Mesenteric Veins; Prospective Studies; Venous Thrombosis
PubMed: 27639007
DOI: 10.1016/j.jvsv.2016.04.002 -
F1000Research 2019The systemic circulation depends upon a highly organized, hierarchal blood vascular network that requires the successful specification of arterial and venous endothelial... (Review)
Review
The systemic circulation depends upon a highly organized, hierarchal blood vascular network that requires the successful specification of arterial and venous endothelial cells during development. This process is driven by a cascade of signaling events (including Hedgehog, vascular endothelial growth factor (VEGF), Notch, connexin (Cx), transforming growth factor-beta (TGF- β), and COUP transcription factor 2 (COUP-TFII)) to influence endothelial cell cycle status and expression of arterial or venous genes and is further regulated by hemodynamic flow. Failure of endothelial cells to properly undergo arteriovenous specification may contribute to vascular malformation and dysfunction, such as in hereditary hemorrhagic telangiectasia (HHT) and capillary malformation-arteriovenous malformation (CM-AVM) where abnormal vessel structures, such as large shunts lacking clear arteriovenous identity and function, thereby compromising peripheral blood flow. This review provides an overview of recent findings in the field of arteriovenous specification and highlights key regulators of this process.
Topics: COUP Transcription Factor II; Cell Cycle; Endothelial Cells; Humans; Signal Transduction; Vascular Endothelial Growth Factor A; Veins
PubMed: 31448079
DOI: 10.12688/f1000research.16701.1 -
Medical Ultrasonography Feb 2022According to a novel in-utero classification termed "umbilical-portal-systemic venous shunt (UPSVS)" recently proposed for an abnormal umbilical, portal and ductal...
AIMS
According to a novel in-utero classification termed "umbilical-portal-systemic venous shunt (UPSVS)" recently proposed for an abnormal umbilical, portal and ductal venous system, the portal-systemic shunt belongs to type III UPSVS. This study was designed to examine the ultrasonographic characteristics and outcome of type III UPSVS.Material and methods: All cases of Type III UPSVS diagnosed at our department from April 2016 to December 2020 were retrospectively studied.
RESULTS
Seventeen patients with type III UPSVS including 12 type IIIa and 5 IIIb cases were identified. Sonography showed a shunt between the inferior left portal vein and the left hepatic vein in all type IIIa cases. Three cases of type IIIb had a combination of another shunt (2 with type I and one with type IIIa). Integrate intrahepatic portal vein system was not seen in those 2 cases of type IIIb combined with type I UPSVS, leading to termination of pregnancy (TOP). TOP occurred in 4 patients with type IIIa as requested by the parents. Two cases (type IIIa and type IIIb each) underwent surgical procedure for the closure of the shunt. Spontaneous complete closure in 4 type IIIa cases and partial closure in one type IIIb case occurred during a period of 3-16 months.
CONCLUSIONS
The majority of patients had type IIIa UPSVS presenting a good outcome. The lack of integrate intrahepatic portal vein system was the main reason for TOP in patients with type IIIb UPSVS. These data suggest the UPSVS classification is a useful tool for a prognosis prediction of type III UPSVS.
Topics: Female; Humans; Portal Vein; Pregnancy; Prognosis; Retrospective Studies
PubMed: 34216452
DOI: 10.11152/mu-3163 -
Frontiers in Immunology 2021Cerebral venous sinus thrombosis (CVST) is a central nervous system disease characterised by thrombosis in cerebral venous or dural sinuses. Autoimmune diseases, a... (Review)
Review
Cerebral venous sinus thrombosis (CVST) is a central nervous system disease characterised by thrombosis in cerebral venous or dural sinuses. Autoimmune diseases, a series of diseases caused by immune responses to autoantigens, are important causes of CVST. The most common diseases that lead to CVST are Behçet's syndrome, systemic lupus erythematosus, antiphospholipid syndrome, and Sjögren's syndrome. Each of these diseases have different clinical and imaging manifestations and treatment for CVST varies by aetiology. This review summarises the characteristics and the current management strategies for autoimmune disease-associated CVST and emphasises controversial therapeutic strategies to provide informative reference information for diagnosis and treatment. Risk factors of autoimmune antigens should not be neglected when unconventional CVST occurs, and both drugs and interventional therapy need further standardisation and discussion with more prospective clinical studies.
Topics: Animals; Anticoagulants; Autoimmune Diseases; Cerebral Veins; Humans; Immunosuppressive Agents; Risk Factors; Sinus Thrombosis, Intracranial
PubMed: 34367137
DOI: 10.3389/fimmu.2021.671101