-
Vascular Pharmacology May 2007Mesenteric veins are more sensitive than arteries to the constrictor effects of sympathetic nerve stimulation and alpha-adrenergic receptor agonists. In the present... (Comparative Study)
Comparative Study
Mesenteric veins are more sensitive than arteries to the constrictor effects of sympathetic nerve stimulation and alpha-adrenergic receptor agonists. In the present study, we tested the hypothesis that alpha(2)-adrenergic receptors (alpha(2)-ARs) contribute to in vitro agonist-induced constriction in veins but not arteries and that alpha(2)-AR function is down-regulated in mesenteric arteries and veins in deoxycorticosterone acetate-salt (DOCA-salt) hypertension. Norepinephrine (NE) concentration-response curves were similar in SHAM and DOCA-salt arteries and veins indicating that adrenergic reactivity of mesenteric blood vessels is not altered in murine DOCA-salt hypertension in vitro. Veins were 30-fold more sensitive to NE than arteries. The alpha(1)-AR antagonist, prazosin (0.003-0.3 microM), produced concentration-dependent rightward shifts of the NE concentration-response curves in arteries but not veins. The alpha(2)-AR agonists, clonidine and UK-14,304, did not constrict arteries or veins in the absence or presence of indomethacin (10 microM) and nitro-L-arginine (NLA; 100 microM). The alpha(2)-AR antagonists, yohimbine (0.003-0.3 microM) and rauwolscine (0.1 microM) did not affect NE responses in SHAM or DOCA-salt arteries but antagonized NE responses in veins. These data indicate that there are different alpha-AR contractile mechanisms in murine mesenteric arteries and veins. Alpha(1)-ARs, but not alpha(2)-ARs, mediate direct contractile responses in arteries and veins while alpha(2)-ARs contribute indirectly to NE-induced constrictions in veins but not arteries in vitro. There may be direct protein-protein interactions between alpha(1)- and alpha(2)-ARs or between their signaling pathways in veins. This contribution of alpha(2)-ARs may account for the greater sensitivity of veins compared to arteries to the contractile effects of NE.
Topics: Adrenergic Antagonists; Adrenergic alpha-Agonists; Animals; Desoxycorticosterone; Disease Models, Animal; Dose-Response Relationship, Drug; Hypertension; Male; Mesenteric Arteries; Mesenteric Veins; Mice; Mice, Inbred C57BL; Norepinephrine; Receptors, Adrenergic, alpha-1; Receptors, Adrenergic, alpha-2; Sodium Chloride; Vasoconstriction; Vasoconstrictor Agents
PubMed: 17329171
DOI: 10.1016/j.vph.2007.01.003 -
Arquivos Brasileiros de Cirurgia... 2014Due to their complexity and risks, mesenteric-portal axis resection and reconstruction during the pancreatectomy procedure were not recommended back in the early...
BACKGROUND
Due to their complexity and risks, mesenteric-portal axis resection and reconstruction during the pancreatectomy procedure were not recommended back in the early nineties. However, as per technical improvements and the reduction in morbidity and mortality rates, they have been routinely indicated in large medical centers.
AIM
To show results from cases of patients subjected to mesenteric-portal axis resection during pancreatectomy.
METHOD
Patients subjected to mesenteric-portal axis resection during pancreatectomy were prospectively and consecutively assessed. The procedure was indicated according to anatomical criteria defined by imaging exams or intraoperative assessment.
RESULTS
Ten patients, half of them were male, with mean age of 55.7 years (40-76) were included. The most frequent underlying diseases were pancreatic adenocarcinoma and Frantz tumor. The circumferential resection of the portal vein associated with the superior mesenteric vein with splenic vein ligature (4 cases=40%) and the primary anastomosis of the vascular stumps (5 cases=50%) were, respectively, the most performed types of vascular resection and reconstruction. Surgery time ranged from 480 to 600 minutes (average=556 minutes) and postoperative hospitalization time ranged from 9 to 114 days (average=34.8 days). Morbidity rate was 60%, and clinical pancreatic fistula (grade B and C) was the most common complication (3 cases=30%). Mortality rate was 10% (1 case).
CONCLUSION
Mesenteric-portal axis resection is a valid technical procedure. It should be taken into account after a clinical assessment that included not only the patients' clinical condition but also the technical and anatomical conditions of the mesenteric-portal axis tumor infiltration as well as life expectancy based on the patient's cancer prognosis.
Topics: Adult; Aged; Female; Humans; Male; Mesenteric Veins; Middle Aged; Pancreatectomy; Portal Vein; Prospective Studies; Treatment Outcome
PubMed: 25626936
DOI: 10.1590/S0102-67202014000400009 -
Diagnostic and Interventional Imaging Nov 2022
Topics: Humans; Mesenteric Veins; Diverticulitis; Colon, Sigmoid; Sigmoid Diseases; Portal Vein
PubMed: 36266193
DOI: 10.1016/j.diii.2022.09.008 -
Journal of Vascular Surgery. Venous and... Sep 2020Superior mesenteric venous thrombosis (MVT) is a poorly understood clinical entity, and as such, outcomes are poorly described. This study aimed to identify predictors... (Comparative Study)
Comparative Study
OBJECTIVE
Superior mesenteric venous thrombosis (MVT) is a poorly understood clinical entity, and as such, outcomes are poorly described. This study aimed to identify predictors of bowel ischemia after MVT and to compare outcomes for patients treated medically (group 1) with those for patients treated with bowel resection (group 2).
METHODS
This was a retrospective, single-institution study capturing all patients diagnosed with symptomatic acute MVT on computed tomography imaging from 2008 to 2018. Demographics, comorbidities, imaging, laboratory values, and treatment were included. Predictors of bowel resection were analyzed by univariate and multivariate statistics. Outcomes including mortality, readmissions for abdominal pain, and chronic mesenteric venous congestion were compared using χ test.
RESULTS
There were 121 patients included in the study; 98 patients were treated medically (group 1), 19 patients were treated with bowel resection (group 2), and 4 patients were treated with endovascular recanalization (group 3). Group 1 and group 2 were compared directly. Patients requiring bowel resection tended to have higher body mass index (P = .051) and a hypercoagulable disorder (P = .003). Patients who required bowel resection were more likely to present with lactic acidosis (P < .001) and leukocytosis (P < .001) with bowel wall thickening on scan (P < .001). On multivariable analysis, a genetic thrombophilia was a strong predictor of bowel ischemia (odds ratio, 3.81; 95% confidence interval, 1.12-12.37). One-year mortality and readmission rates did not differ between groups. However, readmission rates for abdominal pain were high for both groups (group 1, 44.90%; group 2, 57.89%; P = .317), and a significant proportion of patients exhibited chronic mesenteric venous congestion on repeated scan (group 1, 42.86%; group 2, 47.37%; P = .104).
CONCLUSIONS
A genetic hypercoagulable disorder is a predictor of bowel ischemia due to MVT. Regardless of treatment, outcomes after MVT are morbid, with high rates of readmission for abdominal pain. An alternative approach to treat these patients is needed, given the poor outcomes with current strategies.
Topics: Abdominal Pain; Acute Disease; Adult; Aged; Anticoagulants; Digestive System Surgical Procedures; Endovascular Procedures; Female; Humans; Male; Mesenteric Ischemia; Mesenteric Vascular Occlusion; Mesenteric Veins; Middle Aged; Patient Readmission; Retrospective Studies; Risk Assessment; Risk Factors; Splanchnic Circulation; Thrombophilia; Time Factors; Treatment Outcome; Venous Thrombosis
PubMed: 32139329
DOI: 10.1016/j.jvsv.2020.01.007 -
European Journal of Vascular and... 2022Roughly 10% - 20% of pancreatic cancer patients are candidates for curative intent surgical treatment. In the 2000s, many studies showed similar survival rates comparing...
Long Term Results of Pancreatectomy With and Without Venous Resection: A Comparison of Safety and Complications of Spiral Graft, End-to-End and Tangential/Patch Reconstruction Techniques.
OBJECTIVE
Roughly 10% - 20% of pancreatic cancer patients are candidates for curative intent surgical treatment. In the 2000s, many studies showed similar survival rates comparing pancreatic surgery with or without vein resection and reconstruction. The aim was to identify the best method of venous reconstruction.
METHODS
This was a retrospective cohort study. A total of 1 375 patients undergoing pancreatectomy between 2005 and 2018 were identified. Patients undergoing a combined pancreatic resection and venous reconstruction were included retrospectively. When tumour infiltration to the portal/superior mesenteric vein was detected, excision and reconstruction with tangential suturing/patch, end to end anastomosis, or a spiral graft from the great saphenous vein was performed. Next, 90 day and long term survival and outcomes across reconstruction techniques were analysed.
RESULTS
Overall, 198 patients had venous involvement visible in pre-operative scans or detected during surgery, broken down as follows: 171 (86%) pancreaticoduodenectomy, 12 (6%) total pancreatectomy, and 15 (8%) distal pancreatectomy. In total, 69 (35%) spiral graft reconstructions, 77 (39%) end to end anastomoses, and 52 (26%) tangential/patch reconstructions were performed. Tumour histology revealed pancreatic adenocarcinomas in 162 (82%) patients, intraductal mucinous pancreatic neoplasia in 14 (7%), cholangiocarcinoma in five (3%), neuro-endocrine neoplasia in nine (5%), and eight other diagnoses. Overall, 183 (92%) were malignant and 15 (8%) benign. Two patients died within 90 days, one in hospital and one on post-operative day 38 due to thrombosis of the superior mesenteric vein and intestinal necrosis, a Clavien-Dindo grade 5 complication. In addition, 50 (23%) patients had Clavien-Dindo grade 3 - 4 complications. No differences in complications comparing vein reconstruction techniques or in the long term survival of pancreatectomy patients with or without venous reconstruction were detected.
CONCLUSION
The spiral graft technique, used when more advanced venous infiltration occurs, does not increase complications, with outcomes mirroring those accompanying shorter venous resections.
Topics: Humans; Pancreatectomy; Retrospective Studies; Mesenteric Veins; Pancreatic Neoplasms
PubMed: 35462018
DOI: 10.1016/j.ejvs.2022.04.006 -
International Journal of Clinical and... 2014To investigate the changes and contributions of superior mesenteric venous perfusion (SMVP) and splenic venous perfusion (SpVP) to portal venous CT perfusion in canine...
AIM
To investigate the changes and contributions of superior mesenteric venous perfusion (SMVP) and splenic venous perfusion (SpVP) to portal venous CT perfusion in canine model of hepatic diffuse disease.
MATERIALS AND METHODS
By selective catheterization in superior mesenteric and splenic arteries respectively after CT perfusion scanning, SMVP and SpVP became available. Sixteen dogs were adopted and induced by carbon tetrachloride after data under normal conditions were collected. After 3, 6, 9 and 12 months from carbon tetrachloride intervention, liver biopsies by puncture or operation were performed after CT perfusion scanning. SMVP and SpVP under different pathologic conditions were compared and analyzed.
RESULTS
Three stages of hepatic diffuse lesions were defined according to pathologic changes, namely hepatitis, hepatic fibrosis, and cirrhosis. The number of dogs which survived from each stage was: 16 from normal, 12 from hepatitis, 10 from hepatic fibrosis and 4 from cirrhosis. During this progressive period, SpVP ml/(min·100 ml) declined slightly, but there were no significant differences between different stages (P > 0.05). SMVP ml/(min·100 ml) in stage of normal (64.1 ± 8.1) and hepatic fibrosis (44.4 ± 4.5), normal and cirrhosis (42.6 ± 5.4), hepatitis (61.3 ± 6.4) and hepatic fibrosis, hepatitis and cirrhosis was significantly different, but there was no significant difference of SMVP between normal and hepatitis (P = 0.326) or hepatic fibrosis and cirrhosis (P = 0.668).
CONCLUSIONS
With our evidence of interventional CT perfusion, it is mesenteric, not splenic, perfusion that might coincide with hepatic portal venous perfusion during the progressive period of hepatic diffuse disease.
Topics: Animals; Carbon Tetrachloride; Disease Models, Animal; Dogs; Hepatitis, Animal; Liver Cirrhosis; Mesenteric Veins; Radiography; Splenic Vein
PubMed: 25550855
DOI: No ID Found -
International Journal of Surgery... Oct 2020Nontumoral portal vein thrombosis (PVT) is present at liver transplantation (LT) in 5-26% of cirrhotic patients, and is known to affect post LT outcomes. Up to 31% of... (Review)
Review
Nontumoral portal vein thrombosis (PVT) is present at liver transplantation (LT) in 5-26% of cirrhotic patients, and is known to affect post LT outcomes. Up to 31% of patients who are found to have PVT at the time of LT, would have had PVT at the time of initial listing, but others develop PVT during the waiting period. Adequate screening and treatment of the PVT on the waiting list for LT is thus essential so that a portoportal anastomoses can be performed at the time of LT. Early PVT (Yerdel Grade I/II) can be usually managed by thrombectomy, whereas Grade III PVT may require a jump graft from the superior mesenteric vein to the graft PV. Complete portomesenteric thrombosis is a huge challenge, and sometimes a cause for denying a LT in these patients, with multivisceral transplant being the only alternative. The presence of spontaneous, or previously surgically created portosytemic shunts like the leinorenal shunt, may serve as a good inflow option (renoportal anastomosis) in these patients to establish a physiological reconstruction. Although challenging, good outcomes are possible in patients with complex PVT if the appropriate surgical technique is chosen to ensure portal inflow and resolution of PHT post LT.
Topics: Female; Humans; Liver Cirrhosis; Liver Transplantation; Male; Mesenteric Veins; Middle Aged; Portal Vein; Thrombectomy; Vascular Surgical Procedures; Venous Thrombosis; Waiting Lists
PubMed: 32387201
DOI: 10.1016/j.ijsu.2020.04.068 -
Journal of Vascular Research 2021Studies in Cx40-GCaMP2 mice, which express calcium biosensor GCaMP2 in the endothelium under connexin 40 promoter, have identified the unique properties of endothelial... (Comparative Study)
Comparative Study
INTRODUCTION
Studies in Cx40-GCaMP2 mice, which express calcium biosensor GCaMP2 in the endothelium under connexin 40 promoter, have identified the unique properties of endothelial calcium signals. However, Cx40-GCaMP2 mouse is associated with a narrow dynamic range and lack of signal in the venous endothelium. Recent studies have proposed many GCaMPs (GCaMP5/6/7/8) with improved properties although their performance in endothelium-specific calcium studies is not known.
METHODS
We characterized a newly developed mouse line that constitutively expresses GCaMP8 in the endothelium under the VE-cadherin (Cdh5-GCaMP8) promoter. Calcium signals through endothelial IP3 receptors and TRP vanilloid 4 (TRPV4) ion channels were recorded in mesenteric arteries (MAs) and veins from Cdh5-GCaMP8 and Cx40-GCaMP2 mice.
RESULTS
Cdh5-GCaMP8 mice showed lower baseline fluorescence intensity, higher dynamic range, and higher amplitudes of individual calcium signals than Cx40-GCaMP2 mice. Importantly, Cdh5-GCaMP8 mice enabled the first recordings of discrete calcium signals in the intact venous endothelium and revealed striking differences in IP3 receptor and TRPV4 channel calcium signals between MAs and mesenteric veins.
CONCLUSION
Our findings suggest that Cdh5-GCaMP8 mice represent significant improvements in dynamic range, sensitivity for low-intensity signals, and the ability to record calcium signals in venous endothelium.
Topics: Animals; Antigens, CD; Biosensing Techniques; Cadherins; Calcium; Calcium Signaling; Calcium-Binding Proteins; Connexins; Endothelial Cells; Green Fluorescent Proteins; Inositol 1,4,5-Trisphosphate Receptors; Mesenteric Arteries; Mesenteric Veins; Mice, Inbred C57BL; Mice, Transgenic; Microscopy, Fluorescence; Promoter Regions, Genetic; TRPV Cation Channels; Gap Junction alpha-5 Protein; Mice
PubMed: 33706307
DOI: 10.1159/000514210 -
Acta Gastro-enterologica Belgica 2017Ectopic varices are dilated portosystemic venous collaterals located outside of the gastro-esophageal region. Whereas they are common endoscopic findings in patients... (Review)
Review
Ectopic varices are dilated portosystemic venous collaterals located outside of the gastro-esophageal region. Whereas they are common endoscopic findings in patients with portal hypertension, ectopic variceal bleeding is rather rare and accounts for only 1 to 5 % of all variceal bleedings. The rectum and the duodenum are the most common sites for ectopic varices, but they can be present along the whole intestinal tract and neighborhood. At present, there is no consensus well established on diagnostic workup for ectopic variceal bleeding and their therapeutic strategies. Further investigation of large series or randomized-controlled trials is needed because nowadays most of the data available are based on case reports. We report here an unusual case of an ectopic variceal bleeding, presented as an acute small intestine bleeding, due to a portosystemic shunt via dilated mesenteric veins and a varicous left ovarian vein in a patient with alcoholic cirrhosis. The involvement of an ovarian vein in ectopic variceal bleeding is rarely described.
Topics: Choristoma; Collateral Circulation; Disease Management; Endoscopy, Gastrointestinal; Female; Gastrointestinal Hemorrhage; Humans; Liver Cirrhosis, Alcoholic; Mesenteric Veins; Middle Aged; Ovary; Splanchnic Circulation; Varicose Veins
PubMed: 29560669
DOI: No ID Found -
American Journal of Physiology.... Mar 2015Lymphangions, the segments of lymphatic vessels between two adjacent lymphatic valves, actively pump lymph. Acute changes in transmural pressure and lymph flow have...
Lymphangions, the segments of lymphatic vessels between two adjacent lymphatic valves, actively pump lymph. Acute changes in transmural pressure and lymph flow have profound effects on lymphatic pump function in vitro. Chronic changes in pressure and flow in vivo have also been reported to lead to significant changes in lymphangion function. Because changes in pressure and flow are both cause and effect of adaptive processes, characterizing adaptation requires a more fundamental analysis of lymphatic muscle properties. Therefore, the purpose of the present work was to use an intact lymphangion isovolumetric preparation to evaluate changes in mesenteric lymphatic muscle mechanical properties and the intracellular Ca(2+) in response to sustained mesenteric venous hypertension. Bovine mesenteric veins were surgically occluded to create mesenteric venous hypertension. Postnodal mesenteric lymphatic vessels from mesenteric venous hypertension (MVH; n = 6) and sham surgery (Sham; n = 6) animals were isolated and evaluated 3 days after the surgery. Spontaneously contracting MVH vessels generated end-systolic active tension and end-diastolic active tension lower than the Sham vessels. Furthermore, steady-state active tension and intracellular Ca(2+) concentration levels in response to KCl stimulation were also significantly lower in MVH vessels compared with those of the Sham vessels. There was no significant difference in passive tension in lymphatic vessels from the two groups. Taken together, these results suggest that following 3 days of mesenteric venous hypertension, postnodal mesenteric lymphatic vessels adapt to become weaker pumps with decreased cytosolic Ca(2+) concentration.
Topics: Adaptation, Physiological; Animals; Biological Transport, Active; Calcium; Cattle; Disease Models, Animal; Female; Lymph; Lymphatic Vessels; Mesenteric Veins; Muscle Contraction; Muscle, Smooth; Pressure; Time Factors; Venous Pressure
PubMed: 25519727
DOI: 10.1152/ajpregu.00196.2014