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PubMed1988

Thrombosis of the splanchnic veins: CT diagnosis.

Fourteen patients had mesenteric, portal, or splenic venous thrombosis that was diagnosed primarily by contrast-enhanced CT. The group included five patients with coagulopathy, three with pancreatic carcinoma, two with cirrhosis and portal hypertension, one with pancreatitis, and one with hepatocellular carcinoma. In two patients, no etiology was determined. In all cases, CT easily identified low-density venous thrombosis, which frequently involved more than one vein. In four patients, all three splanchnic veins were involved; five patients had occlusion of two veins. In five patients, only one vein was involved. Additional CT findings included ascites, collateral veins, hepatomegaly, and splenomegaly. No venous wall enhancement was found. CT also was helpful in defining the cause of thrombosis in six of 14 patients. Mesenteric edema and/or bowel wall thickening was not identified. None of the patients had classic clinical evidence of splanchnic venous occlusion, and none died primarily of that disease. The major morbidity suffered by these patients stemmed from complications of splanchnic venous occlusion, and nine patients ultimately required sclerotherapy, splenectomy, and portal decompression. We conclude that CT is useful in the diagnosis of splanchnic venous thrombosis. Our experience suggests that mesenteric, splenic, and/or portal venous thrombosis may occur more commonly than has been previously thought and that the disease in many cases is not life threatening.

Adult↗

PubMed1988

Duplex sonography of hepatic artery thrombosis after liver transplantation.

When hepatic artery thrombosis occurs after liver transplantation, another transplantation is required to ensure the patient's survival. Because of the importance of establishing this diagnosis, we reviewed the results of duplex sonography in 37 angiographically or surgically proved cases of hepatic artery thrombosis after liver transplantation. There were 20 children and 17 adults. Ten of the 20 children had angiographically documented hepatopetal arterial collaterals. Such collaterals were not seen in the adult patients. This subset of patients was evaluated separately to determine if intrahepatic arterial blood flow reestablished by collaterals after hepatic artery thrombosis was a cause of false-negative Doppler studies. Thirty-four (92%) of the 37 cases of hepatic artery thrombosis were correctly identified by Doppler. A Doppler pulse was not identified in any of the children with arterial collaterals. We conclude that duplex sonography is sensitive in detecting hepatic artery thrombosis after liver transplantation. Furthermore, the presence of blood flow in hepatopetal arterial collaterals does not cause false-negative examinations.

Adolescent↗

PubMed1991

Diagnosis of portal vein thrombosis: value of color Doppler imaging.

This study was undertaken to determine the accuracy of color Doppler imaging in the diagnosis of portal vein thrombosis. Two hundred fifteen patients were studied with color Doppler imaging to determine patency of the main portal vein. Sonographic findings were confirmed in 75 patients, aged 19 to 66 years. Correlation with angiography was obtained in 13 patients, and surgical correlation was obtained in the remaining 62. Nine patients had portal vein thrombosis on the basis of these gold standards. Sonograms were classified as showing either patency or thrombosis, depending on the ability to show color flow within the main portal vein. Agreement between sonography and angiography or surgery was found in 69 patients (61 patent, eight thrombosed). One patient with a patent portal vein at sonography was found to have a thrombosed vessel at surgery, whereas five patients without portal venous flow at sonography had patent vessels at angiography (one patient) or surgery (four patients). Overall sensitivity and specificity for detection of portal vein thrombosis were 89% and 92%, with an accuracy of 92%, a false-negative rate of 0.11, a negative predictive value of 0.98, and a positive predictive value of 0.62. We postulate that the majority of errors in our study occurred in vessels that, although patent, had only sluggish flow, which could not be resolved because of technical limitations. We conclude that color Doppler imaging is a valuable screening procedure for the assessment of portal vein patency. If the sonogram shows a patent portal vein, no further studies are required. However, a lack of demonstrable flow does not always indicate thrombosis, and other imaging studies should be performed for confirmation.

Adult↗

PubMed1992

Reversed or absent hepatic arterial diastolic flow in liver transplants shown by duplex sonography: a poor predictor of subsequent hepatic artery thrombosis.

OBJECTIVE: We studied the value of absent or reversed diastolic flow in the hepatic artery, shown by duplex sonography of recently transplanted livers, in predicting subsequent hepatic artery thrombosis. MATERIALS AND METHODS: We retrospectively reviewed the records of liver transplantations performed in adults during a 3-year period at our institution. Duplex Doppler studies were done within 24 hr after transplantation and subsequently reviewed. The clinical course of all patients with absent or reversed diastolic flow in the hepatic artery immediately after transplantation was evaluated. RESULTS: Of the 160 liver transplants included in this study, 30 had aberrant diastolic flow in the hepatic artery immediately after transplantation. Twenty had reversed flow, and 10 showed no flow in diastole. In this group of 30 transplants, complications developed in six; two were vascular in origin. One of these complications was thrombosis of the hepatic artery 12 months after transplantation. This 3% thrombosis rate is similar to the 4.6% thrombosis rate of the 130 patients who had antegrade diastolic flow in the hepatic artery immediately after transplantation. CONCLUSION: Reversed or absent diastolic flow in the hepatic artery of a recently transplanted liver has no correlation with subsequent hepatic artery thrombosis.

Diastole↗

PubMedDate not supplied

Portal vein thrombosis in children and adolescents.

OBJECTIVE: To review the literature on portal vein thrombosis in children and adolescents, focusing on its diagnosis, complications and treatment. SOURCES OF DATA: The medical literature of the past 10 years was reviewed using the PubMed and MEDLINE search engines, with major focus on portal vein thrombosis and its clinical outcomes. The following keywords or expressions were used for the web search: portal vein thrombosis, extra-hepatic portal vein obstruction, prognosis, children, portal hypertension, esophagogastric varices. Additionally, we also reviewed the articles cited in the references of the initially selected papers, as well as relevant textbooks. SUMMARY OF THE FINDINGS: Portal vein thrombosis is one of the most common causes of portal hypertension among children. The initial clinical manifestation is characterized either by episodes of upper gastrointestinal bleeding or by splenomegaly on routine clinical examination. The major complications include upper gastrointestinal bleeding, hypersplenism secondary to splenomegaly, growth retardation, and portal biliopathy. The diagnosis is made by abdominal Doppler ultrasonography. Treatment is targeted at the complications and includes primary and secondary prophylaxis against upper gastrointestinal bleeding (which results from the rupture of esophageal varices), and portosystemic shunting in selected cases. CONCLUSIONS: Portal vein thrombosis is one of the major triggers of upper gastrointestinal bleeding in children. Bleeding episodes have a remarkable effect on the quality of life of affected patients. Thus, appropriate diagnosis and treatment are needed in order to reduce morbidity and mortality.

Adolescent↗

PubMed2005

[Factor V Leiden, FII G20210A, MTHFR C677T mutations as risk factors for venous thrombosis during pregnancy and puerperium].

BACKGROUND: Venous thrombosis is the most common cause of obstetric morbidity and mortality during pregnancy and puerperium. The incidence of pregnancy-associated venous thrombosis varies from 1 in 1000 to 1 in 2000 deliveries. Factor V G1691A (FV Leiden), FII G20210A and MTHFR C677T mutations are the most common genetic risk factors for thromboembolism. The aim of this study was to establish the presence of these risk factors in a group of women with an episode of deep venous thrombosis during pregnancy or puerperium. METHODS: The study was carried in a group of 45 women with the first episode of deep venous thrombosis during pregnancy or puerperium. The patients with antiphospholipid antibodies, antithrombin III, protein C or protein S deficiency, and autoimmune and malignant diseases were excluded from the study. FV Leiden, FII G20210A, and MTHFR C677T mutations were detected by polymerase chain reaction, followed by digestion with specific restriction enzymes. RESULTS: Twenty heterozygous carriers of the FV Leiden mutation and one homozygous carrier were detected, which represents the frequencies of 44.4% and 2.2%, respectively. For the FII G20210A mutation, six heterozygous carriers were identified, giving the frequency of 13.3%. The MTHFR C677T mutation was observed in 31 patients (22 heterozygous and 9 homozygous carriers) which represents the frequencies of 48.9% and 20%, respectively. CONCLUSION: Our study suggested that the obligatory testing for FV Leiden and FII G20210A mutations was strongly recommended in women with history of venous thrombosis during pregnancy and puerperium. We found a slight effect of MTHFR 677T allele, but it should be considered in association with other risk factors.

Biomarkers↗

PubMedDate not supplied

Traveler's thrombosis: a systematic review.

BACKGROUND: Anecdotal evidence suggests a possible link between travel and venous thromboembolism (VTE). We systematically evaluated the evidence from observational studies. METHODS: We searched studies evaluating the risk of venous thrombosis in relation to traveling from MEDLINE and EMBASE up tp March 2004, together with a hand search of reference lists from retrieved literature, and we contacted some of the experts. Observational studies estimating the risks of VTE and isolated calf vein thrombosis were eligible. Methodologic quality was assessed based on prior criteria, and meta-analysis was considered where applicable. RESULTS: A total of 194 English-language publications were initially identified. Sixteen studies were included: 9 case-control, 2 prospective controlled, and 5 other observational studies. They differed drastically in study designs, selection of controls where applicable, mode and duration of travel, and subtypes of VTE under consideration. Ten studies concluded that travel, mostly through air and of prolonged duration, is a risk factor for venous thrombosis and/or pulmonary embolism, and the risk increases for passengers with preexisting venous thrombosis risk factors. Outcomes examined ranged from asymptomatic isolated calf muscle vein thrombosis to severe fatal pulmonary embolism. CONCLUSIONS: Current literature is controversial over any association between travel and VTE, and although the quality and power of these studies have been variable, studies of higher quality have shown a strong and significant association between prolonged air travel and VTE. No conclusions could be drawn about other modes of transportation. Since VTE is a disease of multifactorial causation, those with preexisting VTE risk factors are most vulnerable.

Aerospace Medicine↗

PubMed1985

Vasoactive agents and production of thrombosis during intravascular coagulation. 2. alpha-Adrenergic stimulation: effects and mechanisms.

The mechanism whereby norepinephrine elicits thrombosis during intravascular coagulation was investigated further in rabbits given a 4 h infusion of thrombin (1 NIH unit/kg/min). Norepinephrine (3 micrograms/kg/min) combined with thrombin produced glomerular capillary thrombosis in all animals as compared to 4.3% with thrombin alone. Alpha-adrenergic receptors mediated this effect, as indicated (a) by prevention of glomerular thrombosis by dibenzyline but not by methysergide, and (b) by failure of histamine or acetylcholine combined with thrombin to induce the phenomenon. However, in combination with thrombin, these two agents induced duodenal mucosal microthrombosis. Study of the glomerular circulation with colloidal carbon showed that norepinephrine elicits severe glomerular capillary stasis in thrombin treated rabbits; the vasomotor reaction precedes increased fibrinogen consumption and focal deposition of fibrin in the glomeruli. Pretreatment with dibenzyline prevented glomerular stasis and reduced fibrinogen consumption. The phagocytic activity of the reticulo-endothelial system was increased 7 times by thrombin infusions, with or without norepinephrine. We conclude that stimulation of the alpha 1-adrenergic receptors triggers glomerular thrombosis by production of severe glomerular stasis which localizes formation of thrombi in the dilated vessels. These results provide a rational explanation for the role of alpha-adrenergic stimulation in the endotoxin-induced generalized Shwartzman reaction and outline some of the mechanisms and agents implied in the selection of the target organs for thrombosis during intravascular coagulation.

Animals↗

PubMed1994

[Brain MRI findings in patients with initial cerebral thrombosis and the relationship between incidental findings, aging and dementia].

To estimate the relationship between aging, dementia and changes observed on magnetic resonance imaging (MRI) seen in elderly patients with cerebral thrombosis, MRI findings in 103 patients with an initial stroke event (thrombosis group) were compared with those of 37 patients with hypertension/diabetes (high risk group) and 78 patients without those disorders (low risk group). In addition to the causative lesions in the thrombosis group, periventricular hyperintensities (PVH), spotty lesions (SL), silent infarctions (SI), ventricular dilatation (VD), and cortical atrophy (CA) were analyzed in these groups. Infarctions located in the internal capsule/corona radiata were the most frequent causative lesion. Compared to the low risk group, a high incidence of patchy/diffuse PVH, SI, and severe CA was seen in both the thrombosis group and the high risk group. Widespread PVH and multiple SL increased with age in the thrombosis group, while severe CA was seen in each group. SI and VD tended to increase after age 60, though they were not significant. Dementia, diagnosed in 40 out of 78 patients, increased with age. Multivariate analysis revealed the degree of the effects of MRI findings on dementia to be marked in PVH, brain atrophy, causative lesions, and SL, in that order. These results indicated that diffuse PVH and brain atrophy, developing with age, promoted dementia in the elderly with vascular lesions. Moreover, they suggested that a variety of silent brain lesions recognized on MRI other than infarction can affect symptoms in the elderly.

Aged↗

PubMed1999

Dural sinus thrombosis and pseudotumor cerebri: unexpected complications of suboccipital craniotomy and translabyrinthine craniectomy.

OBJECT: The goal of this study was to document the hazards associated with pseudotumor cerebri resulting from transverse sinus thrombosis after tumor resection. Dural sinus thrombosis is a rare and potentially serious complication of suboccipital craniotomy and translabyrinthine craniectomy. Pseudotumor cerebri may occur when venous hypertension develops secondary to outflow obstruction. Previous research indicates that occlusion of a single transverse sinus is well tolerated when the contralateral sinus remains patent. METHODS: The authors report the results in five of a total of 107 patients who underwent suboccipital craniotomy or translabyrinthine craniectomy for resection of a tumor. Postoperatively, these patients developed headache, visual obscuration, and florid papilledema as a result of increased intracranial pressure (ICP). In each patient, the transverse sinus on the treated side was thrombosed; patency of the contralateral sinus was confirmed on magnetic resonance (MR) imaging. Four patients required lumboperitoneal or ventriculoperitoneal shunts and one required medical treatment for increased ICP. All five patients regained their baseline neurological function after treatment. Techniques used to avoid thrombosis during surgery are discussed. CONCLUSIONS: First, the status of the transverse and sigmoid sinuses should be documented using MR venography before patients undergo posterior fossa surgery. Second, thrombosis of a transverse or sigmoid sinus may not be tolerated even if the sinus is nondominant; vision-threatening pseudotumor cerebri may result. Third, MR venography is a reliable, noninvasive means of evaluating the venous sinuses. Fourth, if the diagnosis is made shortly after thrombosis, then direct endovascular thrombolysis with urokinase may be a therapeutic option. If the presentation is delayed, then ophthalmological complications of pseudotumor cerebri can be avoided by administration of a combination of acetazolamide, dexamethasone, lumbar puncture, and possibly lumboperitoneal shunt placement.

Acetazolamide↗

PubMed2001

Superior sagittal sinus thrombosis induced by thyrotoxicosis. Case report.

There is a wide variety of disorders associated with thrombosis of the superior sagittal sinus (SSS), including infectious disease. noninfectious conditions such as vasculitis and hypercoagulable states, and complications arising from pregnancy or use of oral contraceptive medications. Despite these well-defined associations, approximately 25% of the cases remain idiopathic. In this article the authors describe a patient who was found to have SSS thrombosis while experiencing a thyrotoxic phase of Graves disease. The patient presented with intracerebral hemorrhage, subarachnoid hemorrhage, seizure, coma, a raised fibrinogen concentration, low protein C activity, and atrial fibrillations. Thrombolysis was successfully performed despite the coexistence of thrombosis and intracranial hemorrhage. Patients with thyrotoxicosis and a diffuse goiter may be predisposed to the development of SSS thrombosis, as a result of hypercoagulation and stasis of local venous blood flow. In the present case, a patient in whom thrombosis coexisted with intracranial hemorrhage was successfully treated using thrombolytic therapy.

Carotid Arteries↗

PubMed2006

Postoperative dural sinus thrombosis in a patient in a hypercoagulable state. Case report.

Spontaneous cerebral venous sinus thrombosis is a rare problem that may be encountered in patients with underlying thrombophilic disorders. It has also been reported as a postoperative complication following suboccipital, transpetrosal, and transcallosal approaches. The authors report on a 67-year-old man with two prior episodes of lower-extremity deep venous thrombosis who underwent transcallosal resection of a colloid cyst and in whom sagittal sinus thrombosis developed 2 weeks thereafter. Results of a subsequent hematological workup revealed both a factor V Leiden mutation and the presence of antiphospholipid antibodies, two thrombophilic risk factors that likely contributed to the development of delayed postoperative sinus thrombosis. Although the safety of low-molecular-weight heparin (LMWH) after craniotomy has not been established in a randomized, controlled study, there is sufficient evidence to justify its use for prophylactic anticoagulation therapy in patients at high risk for postoperative cerebral venous thrombosis. The authors propose using LMWH prophylaxis in patients with thrombophilic disorders who undergo neurosurgical procedures in proximity to dural sinuses in an effort to prevent catastrophic venous infarction.

Aged↗

PubMed2004

Endothelial induction of fgl2 contributes to thrombosis during acute vascular xenograft rejection.

Thrombosis is a prominent feature of acute vascular rejection (AVR), the current barrier to survival of pig-to-primate xenografts. Fibrinogen-like protein 2 (fgl2/fibroleukin) is an inducible prothrombinase that plays an important role in the pathogenesis of fibrin deposition during viral hepatitis and cytokine-induced fetal loss. We hypothesized that induction of fgl2 on the vascular endothelium of xenografts contributes to thrombosis associated with AVR. We first examined fgl2 as a source of procoagulant activity in the pig-to-primate combination. The porcine fgl2 (pfgl2) was cloned and its chromosomal locus was identified. Recombinant pfgl2 protein expressed in vitro was detected on the cell surface and generated thrombin from human prothrombin. Studies of pig-to-baboon kidney xenografts undergoing AVR in vivo revealed induction of pfgl2 expression on graft vascular endothelial cells (ECs). Cultured porcine ECs activated by human TNF-alpha in vitro demonstrated induction of pfgl2 expression and enhanced activation of human prothrombin. The availability of gene-targeted fgl2-deficient mice allowed the contribution of fgl2 to the pathogenesis of AVR to be directly examined in vivo. Hearts heterotopically transplanted from fgl2(+/+) and fgl2(+/-) mice into Lewis rats developed AVR with intravascular thrombosis associated with induction of fgl2 in graft vascular ECs. In contrast, xenografts from fgl2(-/-) mice were devoid of thrombosis. These observations collectively suggest that induction of fgl2 on the vascular endothelium plays a role in the pathogenesis of AVR-associated thrombosis. Manipulation of fgl2, in combination with other interventions, may yield novel strategies by which to overcome AVR and extend xenograft survival.

Acute Disease↗

PubMed2005

Occupational relevance of subclavian vein thrombosis in association with thoracic outlet syndrome.

OBJECTIVES: Primary subclavian vein thrombosis ("effort thrombosis") is not generally recognized as a work-related disorder, and more knowledge is required on the particular biomechanical risks. An extensive biomechanical risk analysis was performed for a possible work-related case. CASE REPORT: A hard-working 43-year-old race-course farrier received successful surgical treatment for subclavian vein thrombosis. No congenital abnormalities were apparent. At work, the farrier spent 75% of his time with his back bent (generally at > 70 degrees) with his right shoulder flexed and abducted, a position that thereby increased the pressure on the subclavian vein. High average (and peak) stress ratings for the neck and shoulder postures are accompanied by high levels of force and considerable repetitiveness. CONCLUSIONS: Taken together, these forms of biomechanical overload suggest that the leading cause of the subclavian thrombosis suffered by this farrier could have been occupational. Case-control studies on this neglected topic are needed to investigate possible associations between subclavian vein thrombosis and specific occupational activities.

Adult↗

PubMed2004

Fondaparinux or enoxaparin for the initial treatment of symptomatic deep venous thrombosis: a randomized trial.

BACKGROUND: The current standard initial therapies for deep venous thrombosis are low-molecular-weight heparin and unfractionated heparin. In a dose-ranging study of patients with symptomatic deep venous thrombosis, fondaparinux had efficacy and a safety profile similar to those of low-molecular-weight heparin (dalteparin). OBJECTIVE: To evaluate whether fondaparinux has efficacy and safety similar to those of enoxaparin in patients with deep venous thrombosis. DESIGN: Randomized, double-blind study. SETTING: 154 centers worldwide. PATIENTS: 2205 patients with acute symptomatic deep venous thrombosis. INTERVENTION: Fondaparinux, 7.5 mg (5.0 mg in patients weighing <50 kg and 10.0 mg in patients weighing >100 kg) subcutaneously once daily, or enoxaparin, 1 mg/kg of body weight, subcutaneously twice daily for at least 5 days and until vitamin K antagonists induced an international normalized ratio greater than 2.0. MEASUREMENTS: The primary efficacy outcome was the 3-month incidence of symptomatic recurrent venous thromboembolic complications. The main safety outcomes were major bleeding during initial treatment and death. An independent, blinded committee adjudicated all outcomes. RESULTS: 43 (3.9%) of 1098 patients randomly assigned to fondaparinux had recurrent thromboembolic events compared with 45 (4.1%) of 1107 patients randomly assigned to enoxaparin (absolute difference, -0.15 percentage point [95% CI, -1.8 to 1.5 percentage points]). Major bleeding occurred in 1.1% of patients receiving fondaparinux and 1.2% of patients receiving enoxaparin. Mortality rates were 3.8% and 3.0%, respectively. LIMITATIONS: Follow-up was incomplete in 0.4% of fondaparinux-treated patients and 1.0% of enoxaparin-treated patients. CONCLUSIONS: Once-daily subcutaneous fondaparinux was at least as effective (not inferior) and safe as twice-daily, body weight-adjusted enoxaparin in the initial treatment of patients with symptomatic deep venous thrombosis.

Aged↗

PubMed1976

Renal vein thrombosis, nephrotic syndrome, and systemic lupus erythematosus: an association in four cases.

We report here four cases of systemic lupus erythematosus associated with the nephrotic syndrome and renal vein thrombosis and review six familiar cases previously noted in the literature. Renal biopsy in each of our cases showed changes consistent with the membranous type of lupus nephropathy. We discuss the exclusive appearance of this pattern in relation to renal vein thrombosis in other forms of renal disease. The occurance of renal vein thrombosis in patients with systemic lupus erythematosus and the nephrotic syndrome supports the evidence that the thrombosis is a complication rather than a cause of the nephrotic syndrome. The presence of pleuritic pain in a patient with systemic lupus erythematosus and the nephrotic syndrome should alert the clinician to the possibility of renal vein thrombosis and pulmonary emboli. With appropriate diagnosis and anticoagulation therapy, our patients had a benign course during 7 to 48 months of follow-up.

Adult↗

PubMed1980

Thrombosis in patients with the lupus anticoagulant.

A retrospective study was carried out to determine the frequency of thrombosis in patients with the lupus anticoagulant. Thirty-five patients fulfilled laboratory criteria for the diagnosis of the lupus anticoagulant. Eight of these patients had evidence of clinically significant thrombosis while their plasma showed a prolonged partial thromboplastin time due to the anticoagulant. Four of the patients wity thrombosis had concurrent autoimmune disease and three other patients were receiving phenothiazine medication. Moderate thrombocytopenia was noted in four patients with thrombosis. None of the patients with the lupus anticoagulant bled abnormally. This study suggests that patients with the lupus anticoagulant may be at increased risk of thrombosis.

Adolescent↗

PubMed1987

Sonographic diagnosis of subclavian and internal jugular vein thrombosis.

Seven patients with internal jugular and/or subclavian vein thrombosis were studied with real-time sonography and venography. High-resolution real-time sonography was used to tabulate morphologic parameters (venous size, shape, intraluminal echoes, and presence of collateral veins), as well as physiologic parameters (mobile venous valves, distention, compressibility, pulsation). Chronic venous thrombosis was characterized by the presence of collateral veins, spread of the thrombus to other major veins, and loss of normal vascular landmarks with poor visualization of the actual thrombus, the "cut-off sign." Acute catheter-induced thrombosis was confined to one vessel, and the thrombus was seen clearly in all cases. Two new signs of thrombosis, the absence of the beating venous valve and the "cut-off sign," are particularly useful in the sonographic diagnosis of internal jugular vein thrombosis.

Humans↗