Clinical manifestations and imaging tools in the diagnosis of splanchnic and cerebral vein thromboses

Acute splanchnic venous thrombosis following laparoscopic sleeve gastrectomy: A case report

INTRODUCTION AND IMPORTANCE

Splanchnic venous thrombosis is a rare but serious complication of bariatric surgery. This case report highlights a unique occurrence of acute portal, mesenteric, and splenic vein thrombosis in a 39-year-old woman three weeks after undergoing laparoscopic sleeve gastrectomy for severe obesity.

CASE PRESENTATION

A 39-year-old woman with a BMI of 38.1 kg/m2 and no prior medical history presented with a six-day history of diffuse abdominal pain, nausea and subjective fever but no change in bowel habits or blood in stool. A CT scan abdomen with IV contrast revealed extensive thrombosis involving the intrahepatic and extrahepatic veins, extending to the portal, splenic, and mesenteric veins. Laboratory findings supported a hypercoagulable state. Treatment included anticoagulation, intravenous antibiotics, supportive care, and close monitoring.

CLINICAL DISCUSSION

Diagnosing SVT is difficult due to its non-specific symptoms, relying on advanced imaging techniques like Doppler ultrasound, CT, or MRI. Anticoagulation therapy, such as low-molecular-weight heparin (LMWH) followed by direct oral anticoagulants (DOACs), is essential for managing SVT. Supportive treatments, including PPIs and antibiotics, improve outcomes, and surgery may be necessary for complicated cases like end organ damage for instance intestinal ischemia and necrosis.

CONCLUSION

This case underscores the need for high clinical suspicion of splanchnic venous thrombosis in post-bariatric surgery patients presenting with persistent abdominal pain. Proper patient selection and stratification, adequate thromboprophylaxis are crucial preventive strategies. Early diagnosis and aggressive management with multidisciplinary team approach are critical to preventing severe complications and improving outcomes.

Incidence and Management of Splanchnic Vein Thrombosis in Pancreatic Diseases

Splanchnic vein thrombosis (SVT) in pancreatic disease has a 20%-30% incidence rate, leading to increased mortality and complication rates. Therefore, the aim of this review is to summarize recent evidence about the incidence, risk factors, and management of pancreatic cancer, pancreatic cystic neoplasm-, and pancreatitis-related SVT. Doppler ultrasound should be the first imaging choice, followed by contrast-enhanced computed tomography or magnetic resonance imaging. Data regarding SVT treatment in acute pancreatitis and pancreatic cancer are scarce; however, for venous thromboembolism treatment, direct oral anticoagulants and low molecular weight heparin have been effective. Further trials must investigate the length of anticoagulant treatment and the need for interventional radiological procedures.

Cerebral venous thrombosis as a rare complication of Sjögren's syndrome: case series and literature review

OBJECTIVE

As few cerebral venous thrombosis (CVT) patients with primary Sjögren's syndrome (pSS) have been reported, little is known about the characteristics of this rare complication. This study is aimed at describing the clinical features, treatment, and outcome of CVT combined with pSS.

MATERIALS AND METHODS

We reported five patients of CVT and pSS admitted to our hospital and searched the relevant case reports in PubMed for literature review.

RESULTS

We reviewed a total of twelve patients with pSS and CVT. Among them, five patients were from our report in the present paper, and seven other patients were from the case reports searched in PubMed. In total twelve patients, eleven patients were female. The twelve patients had an average age of 43.7 ± 8.3 years (age range, 26-57 years). The symptoms of pSS included multiple caries (50%), dry mouth (41.7%), dry eyes (33.3%), arthritis symptoms (16.7%), and parotid gland swelling (8.3%). Headache was the most common neurological symptom in all patients. Four patients (33.3%) had no clinical symptoms associated with pSS. Anti-SSA antibodies were positive in all patients. Antiphospholipid antibodies (aPLs) were positive in 33.3% of patients. Unilateral transverse sinus (75.0%) was the most commonly involved venous sinus. All patients received anticoagulant therapy. Hydroxychloroquine was also administered to the patients. Seven patients were treated with glucocorticoids. All patients recovered completely with no clinical or radiological recurrence.

CONCLUSION

pSS combined with CVT is a rare condition. Middle-aged women with pSS should be alert to the presence of CVT. It is of great importance to screen for autoimmune diseases during the clinical course of CVT, especially in patients with unilateral transverse sinus thrombosis. Effective treatment strategies require further study. Key Points • Patients combined with CVT are very rare. • Screening for autoimmune diseases in CVT patients is great important. • Patients may have good prognosis when effective treatment is administrated.

Anticoagulation for splanchnic vein thrombosis in myeloproliferative neoplasms: a systematic review and meta-analysis

BACKGROUND

Optimal anticoagulation management in patients with myeloproliferative neoplasms (MPN) experiencing splanchnic vein thrombosis (SpVT) requires balancing risks of bleeding and recurrent thrombosis.

OBJECTIVES

We conducted a systematic review and meta-analysis to assess the incidence of bleeding and thrombosis recurrence in patients with MPN-SpVT.

METHODS

We included retrospective or prospective studies in English with ≥10 adult patients with MPN-SpVT. Outcomes included recurrent venous thrombosis (SpVT and non-SpVT), arterial thrombosis, and major bleeding. Pooled rates per 100 patient years with 95% CIs were calculated by DerSimonian-Laird method using random-effects model.

RESULTS

Out of 4624 studies screened, 9 studies with a total of 443 patients were included in the meta-analysis with median follow-up of 3.5 years. In the 364 patients with MPN-SpVT treated with anticoagulation, pooled event rate for major bleeding was 2.8 (95% CI, 1.5-5.1; I2 = 95%), for recurrent venous thrombosis was 1.4 (95% CI, 0.8-2.2; I2 = 72%), and for arterial thrombosis was 1.4 (95% CI, 0.6-3.3; I2 = 92%) per 100 patient years. Among 79 patients (n = 4 studies) who did not receive anticoagulation, pooled event rate for major bleeding was 3.2 (95% CI, 0.7-12.7; I2 = 97%), for recurrent venous thrombosis 3.5 (95% CI, 1.8-6.4; I2 = 88%), and for arterial thrombosis rate 1.6 (95% CI, 0.4-6.6; I2 = 95%) per 100 patient years.

CONCLUSION

Patients with MPN-SpVT treated with anticoagulation have significant risks for both major bleeding and thrombosis recurrence. Further studies are necessary to determine the optimal anticoagulation approach in patients with MPN-SpVT.

Splanchnic Vein Thrombosis: The State-of-the-Art on Anticoagulant Treatment

Splanchnic vein thrombosis (SVT) is a rare type of venous thromboembolism occurring within the splanchnic venous system. Portal vein thrombosis is the most common presentation, while Budd-Chiari syndrome is the least common. Liver cirrhosis and abdominal solid cancer are the main local risk factors for SVT, whereas myeloproliferative neoplasms are the predominant systemic risk factors. Signs and symptoms of SVT are nonspecific and include abdominal pain, gastrointestinal bleeding, and ascites. Asymptomatic SVT is not uncommon, and the majority would be detected incidentally on routine abdominal imaging performed for the follow-up of liver diseases and tumors. The management of SVT aims to prevent thrombus progression, promote vessel recanalization, and prevent recurrent venous thromboembolism. Anticoagulation should be started early in order to increase the chances of vessel recanalization and reduce the risk of portal hypertension-related complications. Direct oral anticoagulants have been included in recent guidelines, as alternatives to vitamin K antagonists, after clinical stability has been reached; however, caution is required in patients with liver or kidney dysfunction. Treatment duration is based on the presence (or absence) and type (transient vs. permanent) of risk factors. This narrative review aims to summarize the latest evidence on SVT, with a particular focus on the anticoagulant treatment in special categories of patients (e.g., liver cirrhosis, solid cancer, myeloproliferative neoplasms, pancreatitis, incidentally detected SVT, Budd-Chiari syndrome, and chronic SVT).

Cancer-associated splanchnic vein thrombosis: Clinical implications and management considerations

Splanchnic vein thrombosis (SVT), a thrombosis which involves the portal, mesenteric, and splenic veins, and the Budd-Chiari syndrome, represents an uncommon type of venous thromboembolism (VTE). Like with deep vein thrombosis of the lower extremities and pulmonary embolism, ample evidence suggests a significant association between SVT and cancer, particularly intra-abdominal solid malignancies (e.g. hepatobiliary and pancreatic cancers) and myeloproliferative neoplasms (MPN). Clinical symptoms of SVT in cancer patients can be ambiguous, and frequently attributed to the primary cancer itself. Alternatively, SVT may be asymptomatic and detected incidentally during cancer staging or follow-up evaluations. SVT can also precede the diagnosis of cancer and has been associated with poorer outcomes in patients with liver or pancreatic cancers. Therefore, an unprovoked SVT warrants a thorough evaluation for an underlying malignancy or MPN. Cancer-associated SVT carries a high risk of VTE extension, recurrence and bleeding. Extended anticoagulant treatment is often required in the absence of a high bleeding risk. Guidelines suggest treatment with either low molecular weight heparin (LMWH) or direct oral anticoagulants (DOACs), although available data on the safety and effectiveness of DOACs in these patients is limited. This comprehensive review outlines the epidemiology, pathogenesis, risk factors, and diagnosis of cancer-associated SVT and underscores the importance of comprehensive patient evaluation and evidence-based management.

Cancer-Associated Abdominal Vein Thrombosis

Cancer is associated with an increased risk of developing venous thromboembolism, due to its direct influence on the three pillars of Virchow's triad (e.g., compression on the blood vessels by the tumour, blood vessels invasion, and cytokine release), together with the effect of exogenous factors (such as chemotherapy, radiotherapy, surgery). In cancer patients, the risk of thrombosis at unusual sites, such as splanchnic, ovarian and renal vein thrombosis, is also increased. Abdominal vein thromboses are frequently incidental findings on abdominal imaging performed as part of the diagnostic/staging workup or the follow-up care of malignancies. There is little evidence on the management of unusual site venous thromboembolism in cancer patients since there are only a few specific recommendations; thus, the management follows the general principles of the treatment of cancer-associated deep vein thrombosis and pulmonary embolism. This narrative review summarises the latest evidence on cancer-associated abdominal vein thrombosis, i.e., thrombosis of the splanchnic, ovarian and renal veins.

Cancer-associated splanchnic vein thrombosis: Clinical features upon diagnosis and short-term outcomes

INTRODUCTION

The incidence of splanchnic vein thrombosis (SVT) in cancer patients has increased in recent years and its real clinical significance and management can be challenging. This study aimed to describe the clinical presentation and short-term outcomes of patients with cancer-associated SVT.

MATERIAL AND METHODS

This was a retrospective observational study of consecutive patients with cancer-associated SVT diagnosed during the period 2015-2020. The primary objective was to describe the clinical presentation of SVT. Patients were clinically classified into two groups based on the presence of symptoms on SVT diagnosis. The main outcomes were overall and SVT-related mortality, major and non-major bleeding rates, and the thrombosis recurrence rate in the first 30 days of follow-up.

RESULTS

This study enrolled 203 patients. Intra-abdominal tumors (76 %) and metastatic disease (68 %) predominated. A total of 79 (39 %) patients without symptoms were diagnosed with SVT during a scheduled radiological test and were classified as "asymptomatic", while 124 (61 %) patients presented some potential SVT symptoms and were considered as "symptomatic". Although the 30-day outcomes showed no significant differences between the two groups, mortality in the asymptomatic group was slightly lower compared to the symptomatic group (3 % vs. 10 %, p = 0.085).

CONCLUSIONS

Almost 40 % of cases of cancer-associated SVT are asymptomatic. There were no significant differences in short-term outcomes between the symptomatic and asymptomatic patients. More studies are required to better define long-term management and outcomes in these patients.

Vascular complications of chronic pancreatitis and its management

Chronic pancreatitis is a chronic fibro-inflammatory disorder of the pancreas, resulting in recurrent abdominal pain, diabetes mellitus, and malnutrition. It may lead to various other complications such as pseudocyst formation, benign biliary stricture, gastric outlet obstruction; and vascular complications like venous thrombosis, variceal and pseudoaneurysmal bleed. Development of varices is usually due to chronic venous thrombosis with collateral formation and variceal bleeding can easily be tackled by endoscopic therapy. Pseudoaneurysmal bleed can be catastrophic and requires radiological interventions including digital subtraction angiography followed by endovascular obliteration, or sometimes with a percutaneous or an endoscopic ultrasound-guided approach in technically difficult situations. Procedure-related bleed is usually venous and mostly managed conservatively. Procedure-related arterial bleed, however, may require radiological interventions.

Utility of 3D T1-weighted turbo spin echo black blood sequence for the diagnosis of cerebral venous thrombosis

PURPOSE

Accurate assessment of dural sinus, deep and cortical venous thrombosis on MR imaging is challenging. The aim of this study is to evaluate the accuracy of 3D-T1 turbo spin echo (T1S), sequences in detecting venous thrombosis and comparing it with susceptibility-weighted imaging (SWI), magnetic resonance venography (MRV) and post contrast T1 magnetization-prepared rapid acquisition gradient echo (T1C).

METHODS

A blinded retrospective observational analysis of 71 consecutive patients evaluated for cerebral venous thrombosis (CVT) and 30 control patients was performed. Multimodality reference standard adopted included T1C, SWI with MRV. Sub-analyses in superficial, deep and cortical venous segments were performed in addition to correlation of signal intensity of thrombus with the clinical stage.

RESULTS

A total of 2222 segments in 101 complete MRI examinations were evaluated. Sensitivity/specificity/positive predictive value/negative predictive value/accuracy and precision of T1S for detection of cortical vein thrombosis was 0.994/1/1/0.967/0.995/1, 1/0.874/0.949/1/0.963/0.950 for detection of superficial venous sinus thrombosis and 1/1/1/1/1/1 for deep venous thrombosis. The AUC yield for T1S was 0.997 for cortical, 1 for deep and 0.988 for superficial venous segments.

CONCLUSION

T1S paralleled the accuracy of conventional sequences in the overall detection of CVT but showed superior accuracy in the detection of cortical venous thrombosis. It makes a fitting addition to the CVT MRI protocol in scenarios demanding negation of gadolinium administration.

Anticoagulant therapy for splanchnic vein thrombosis: recent updates for patients with liver cirrhosis

INTRODUCTION

Liver cirrhosis is accompanied by several hemostatic alterations, which contribute to the current theory of "rebalanced hemostasis." Splanchnic vein thrombosis (SVT) is a frequent complication of liver cirrhosis (17-26% of the cirrhotic patients), and liver cirrhosis is a common risk factor for SVT (24-28% of SVT cases).

AREAS COVERED

This narrative review aims to describe the current state of the art on the anticoagulant treatment of cirrhotic SVT, with a particular focus on the possible role of the direct oral anticoagulants (DOACs) and recent guidelines on this topic.

EXPERT OPINION

Early anticoagulant therapy is recommended in cirrhotic patients with acute SVT, to obtain vessel recanalization and decrease the rates of portal hypertension-related complications. Gastroesophageal varices do not represent a contraindication to anticoagulation, if adequate prophylaxis of variceal bleeding is established, and varices band ligation can be safely performed without the need to stop the anticoagulant treatment. The conventional treatment of cirrhotic SVT consisted of low molecular weight heparin, as initial treatment of choice, eventually followed by vitamin K antagonists, but the DOACs can be considered as a reasonable alternative in patients with compensated liver cirrhosis.

Shedding Light on the Pathogenesis of Splanchnic Vein Thrombosis

Splanchnic vein thrombosis is a rare but potentially life-threatening manifestation of venous thromboembolism, with challenging implications both at the pathological and therapeutic level. It is frequently associated with liver cirrhosis, but it could also be provoked by myeloproliferative disorders, cancer of various gastroenterological origin, abdominal infections and thrombophilia. A portion of splanchnic vein thrombosis is still classified as idiopathic. Here, we review the mechanisms of splanchnic vein thrombosis, including new insights on the role of clonal hematopoiesis in idiopathic SVT pathogenesis, with important implications from the therapeutic standpoint.

Vaccine-induced immune thrombotic thrombocytopenia with atypical vein thrombosis: Implications for clinical practice

OBJECTIVES

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a new and rare syndrome resulting from the largest vaccination campaign against SARS-CoV-2 in the history of mankind. The aim of this review is to clarify underlying mechanisms, pathology, diagnosis, and therapy, with the related clinical implications.

METHODS

We performed a comprehensive literature review in order to collect the clinical and treatment data about patients suffering from VITT. PubMed, Ovid Medline, Ovid EMBASE, Scopus, and Web of Science were screened regarding patients who developed VITT. Last search was launched on June 30^th 2021.

RESULTS

Abdominal and/or neurological symptoms develop between 5 and 20 days after vaccine administration and do not involve the lower extremities. VITT is suspected if the platelet count is lower than 100.000/mm³ and D-dimer is higher than the age-adjusted range. Medical treatment is mainly based on intravenous immunoglobulins, corticosteroids, and anticoagulant drugs with a short plasma half-life, but the complete avoidance of low molecular weight heparin is recommended. Endovascular treatment and/or decompressive craniectomy might be an option in a minority of cases.

CONCLUSION

Due to widespread vaccination concerns, the vascular specialist and phlebologist are increasingly consulted to prevent or diagnose VITT. The latter has peculiar and completely different localizations, symptoms, and treatment compared to the common pictures of venous thrombosis.

Case Report: Splanchnic Vein Thrombosis as a Complication of Necrotizing Acute Pancreatitis in a Pediatric Patient

Splanchnic vein thrombosis is an unusual manifestation of venous thromboembolism and includes portal vein thrombosis, mesenteric veins thrombosis, splenic vein thrombosis, and the Budd-Chiari syndrome. The most common risk factors include hematologic and autoimmune disorders, hormonal therapy, liver cirrhosis, solid abdominal cancer, recent abdominal surgery, and abdominal infections or inflammatory conditions, such as pancreatitis. Splanchnic vein thrombosis in acute pancreatitis is most commonly associated with the severe form of the disease and pancreatic necrosis. This report describes a case of splanchnic vein thrombosis as a complication of necrotizing acute pancreatitis in a pediatric patient. Splanchnic vein thrombosis was incidentally detected on contrast-enhanced computed tomography to assess the pancreas. There was no evidence of prior risk factors for the thrombotic condition. The patient was treated with anticoagulation and showed complete resolution after recovery from necrotizing acute pancreatitis, at a 16-month follow-up. The complication of necrotizing acute pancreatitis with splanchnic vein thrombosis in pediatric age is a rare presentation.

Narrative review of portal vein thrombosis in cirrhosis: pathophysiology, diagnosis, and management from an interventional radiology perspective

OBJECTIVE

This paper examines the incidence, clinical presentation, and pathophysiology of portal vein thrombosis (PVT) in cirrhosis. Additionally, we have reviewed the literature regarding the current status of medical and interventional radiology management of PVT and have proposed a novel algorithm for the management given different clinical scenarios. Lastly two representative cases displaying endovascular treatment options are provided.

BACKGROUND

Portal vein thrombus in the setting of cirrhosis is an increasingly recognized clinical issue with debate on its pathophysiology, natural course, and optimal treatment. Approximately one-third of patients are asymptomatic, and detection of the thrombus is an incidental finding on imaging performed for other reasons. In 30% to 50% of patients, PVT resolves spontaneously. However, there is increased post-transplant mortality in patients with completely occlusive PVT, therefore effective early revascularization strategies are needed for patients with complete PVT who are expected to undergo liver transplant. Additionally, no consensus has been reached regarding PVT treatment in terms of timing and type of interventions as well as type and duration of anticoagulation.

METHODS

Computerized literature search as well as discussion with experts in the field.

CONCLUSIONS

Management of PVT is complex, as many variables affect which treatments can be used. Anticoagulation appears to be the optimal first-line treatment in patients with acute PVT but without bleeding varices or mesenteric ischemia. Minimally invasive treatments include various methods of mechanical thrombectomy, chemical thrombolysis, and transjugular intrahepatic portosystemic shunt (TIPS) placement with or without variceal embolization. Definitive recommendations are difficult due to lack of high quality data and continued research is needed to evaluate the efficacy of different anticoagulants as well as the timing and use of various minimally invasive therapies in specific circumstances.

Relationship between portal vein width and portal vein thrombosis in patients with hepatitis B cirrhosis

BACKGROUND

The early diagnosis of portal vein thrombosis (PVT) is still a difficult clinical problem. There is an urgent need to find noninvasive indexes that can predict PVT.

AIM

To investigate the relationship between portal vein width and PVT.

METHODS

A total of 418 patients with hepatitis B cirrhosis were collected. They were divided into a PVT group (n = 66) and a non-PVT group (n = 352) according to whether PVT occurred. The general data of the two groups were compared, and the risk factors affecting PVT were analyzed retrospectively by multivariate logistic regression. The effectiveness of different risk factors in predicting PVT was evaluated by receiver operating characteristic (ROC) curve analysis.

RESULTS

Compared with the non-PVT group, the PVT group had a significantly higher Child-Pugh score, lower rate of Child-Pugh A class, higher platelet count and D-dimer level, wider portal vein width, and slower portal vein blood flow (P < 0.05). Logistic regression showed that portal vein width (odds ratio [OR] = 3.941, P = 0.001), portal vein blood flow (OR = 0.841, P = 0.007), platelet count (OR = 1.024, P = 0.008), and D-dimer level (OR = 2.383, P = 0.000) were independent risk factors for PVT in patients with liver cirrhosis. The maximum area under the ROC curve of portal vein width in the diagnosis of PVT was 0.874, and the best diagnostic threshold was > 12.5 mm, with a predictive sensitivity and specificity of 78% and 82%, respectively.

CONCLUSION

The increase of portal vein diameter is a risk factor for PVT in patients with liver cirrhosis.

Diagnostic accuracy of D-dimer in patients at high-risk for splanchnic vein thrombosis: A systematic review and meta-analysis

BACKGROUND

D-dimer is included in the diagnostic algorithm for deep vein thrombosis and pulmonary embolism. However, its role in the diagnosis of splanchnic vein thrombosis (SVT) is still controversial. The aim of this study was to evaluate the diagnostic accuracy of D-dimer for SVT.

METHODS

We performed a systematic review of the literature with meta-analysis (PROSPERO protocol registration number: CRD42020184300). The electronic databases MEDLINE, EMBASE, and CENTRAL were searched from inception to March 2021 week 4. Studies which evaluated D-dimer accuracy for SVT in any category of patients were selected. The index test was any D-dimer assay; the reference standard was any radiological imaging. The QUADAS-2 checklist was used for the risk of bias assessment. A bivariate random-effects regression model was used to calculate summary estimates of sensitivity and specificity.

RESULTS

12 studies (with a total of 1298 patients) evaluating the accuracy of D-dimer in patients at high risk of SVT (surgical patients, patients with liver cirrhosis or hepatocellular carcinoma) were included. None of the included studies was at low risk of bias. The weighted mean prevalence of SVT was 33.4% (95% CI, 22.5-45.2%, I2 = 94.8%). D-dimer accuracy was expressed by sensitivity 96% (95% CI, 72-100%); specificity 25% (95% CI, 5-67%); positive likelihood ratio 1.3 (95% CI, 0.9-1.9); negative likelihood ratio 0.16 (95% CI, 0.03-0.84); area under the ROC curve 0.80 (95% CI, 0.76-0.83).

CONCLUSIONS

D-dimer seems to have high sensitivity in the diagnosis of patients at high-risk for SVT. However, there is a strong need for more robust evidence on this topic.

Anticoagulant therapy for splanchnic vein thrombosis: a systematic review and meta-analysis

Treatment of splanchnic vein thrombosis (SVT) is challenging, and evidence to guide therapeutic decisions remains scarce. The objective of this systematic review and meta-analysis was to determine the efficacy and safety of anticoagulant therapy for SVT. MEDLINE, EMBASE, and clinicaltrials.gov were searched from inception through December 2019, without language restrictions, to include observational studies and randomized controlled trials reporting radiological or clinical outcomes in patients with SVT. Pooled proportions and risk ratios (RRs) with 95% confidence intervals (CIs) were calculated in a random-effects model. Of 4312 records identified by the search, 97 studies including 7969 patients were analyzed. In patients receiving anticoagulation, the rates of SVT recanalization, SVT progression, recurrent venous thromboembolism (VTE), major bleeding, and overall mortality were 58% (95% CI, 51-64), 5% (95% CI, 3-7), 11% (95% CI, 8-15), 9% (95% CI, 7-12), and 11% (95% CI, 9-14), respectively. The corresponding values in patients without anticoagulation were 22% (95% CI, 15-31), 15% (95% CI, 8-27), 14% (95% CI, 9-21), 16% (95% CI, 13-20), and 25% (95% CI, 20-31). Compared with no treatment, anticoagulant therapy obtained higher recanalization (RR, 2.39; 95% CI, 1.66-3.44) and lower thrombosis progression (RR, 0.24; 95% CI, 0.13-0.42), major bleeding (RR, 0.73; 95% CI, 0.58-0.92), and overall mortality (RR, 0.45; 95% CI, 0.33-0.60). These results demonstrate that anticoagulant therapy improves SVT recanalization and reduces the risk of thrombosis progression without increasing major bleeding. The incidence of recurrent VTE remained substantial in patients receiving anticoagulation, as well. Effects were consistent across the different subgroups of patients. This trial was registered on the PROPERO database at (https://www.crd.york.ac.uk/prospero//display_record.php?ID=CRD42019127870) as #CRD42019127870.

Cancer-Associated Splanchnic Vein Thrombosis

Splanchnic vein thrombosis (SVT), which includes portal, mesenteric, and splenic vein thrombosis and the Budd-Chiari syndrome, is an infrequent manifestation of venous thromboembolism (VTE). Like typical site VTE, SVT is also frequently associated with cancer, particularly intra-abdominal solid malignancies and myeloproliferative neoplasms (MPNs). The clinical presentation of SVT is nonspecific. Symptoms may be related to the underlying malignancy, and thrombosis is incidentally diagnosed by imaging studies for cancer staging or follow-up in a substantial proportion of cases. The occurrence of SVT predicts worse prognosis in patients with liver or pancreatic cancer and, not uncommonly, SVT may precede the diagnosis of cancer. Therefore, the occurrence of an apparently unprovoked SVT should prompt careful patient evaluation for the presence of an underlying malignancy or MPN. Cancer patients carry a high risk of VTE extension and recurrence and long-term anticoagulant treatment is suggested in the absence of high risk of bleeding. Either LMWH or direct oral anticoagulants (DOACs) are suggested for the treatment of patients with cancer-related SVT, although limited experience is available on the use of DOACs in these settings. Vitamin K antagonists (VKAs) are suggested for the short and long-term treatment of SVT associated with MPN. This review outlines the epidemiological aspects, pathogenesis, risk factors, and diagnosis of cancer-associated SVT, and addresses questions regarding the management of this challenging condition.

Treatment of portal vein thrombosis: an updated narrative review

Portal vein thrombosis (PVT) is the most frequent among the splanchnic vein thrombosis, accounting for 90% of cases. More than half of PVT are provoked by liver cirrhosis, solid cancer or myeloproliferative neoplasms. The remaining cases are non-malignant non-cirrhotic PVT and include either unprovoked events or thrombosis secondary to other less common risk factors (e.g. abdominal surgery, intrabdominal inflammations/infections, or hormonal stimuli). Anticoagulant therapy in patients with acute symptomatic PVT should be started early after diagnosis, if no active bleeding, to obtain greater vessel recanalization and reduce the occurrence of portal-hypertension related complications. Gastroesophageal varices do not represent a contraindication to anticoagulant treatment, as long as adequate measures have been undertaken for the prophylaxis of gastroesophageal bleeding. Different treatment options (unfractionated or low molecular weight heparin, vitamin K antagonists and direct oral anticoagulants [DOACs]) can be considered. In this narrative review we will discuss the treatment of PVT in the three most common scenarios (cirrhosis-associated, cancer-associated and non-malignant non-cirrhotic PVT). We will also discuss the role of the DOACs and summarise recent guidelines on this topic.

Cerebral venous thrombosis

Cerebral venous thrombosis (CVT) is a rare form of deep venous thrombosis (DVT), yet a leading cause of stroke in young adults, with an incidence that seems to be increasing in recent years. Risk factors for CVT overlap with those of DVT in other locations, with the addition of local risk factors, such as infections, head trauma and neurosurgery. The clinical presentation is highly variable, hence the diagnosis of CVT may be delayed or overlooked. Early recognition and timely initiation of anticoagulant treatment are of essence, while decompressive surgery can be lifesaving for patients with impending transtentorial herniation. Concomitant intracranial hemorrhage is not a contraindication to anticoagulant treatment. Endovascular treatment may be suggested for selected patients who deteriorate despite anticoagulant treatment. In this review we will provide an extensive and contemporary discussion of the incidence, pathophysiology, risk factors, clinical presentation, neuroimaging and management of CVT, in accordance with recent guidelines. Additionally, we will summarize the latest data with regards to direct oral anticoagulants (DOACs) treatment in CVT.

Current imaging modalities for diagnosing cerebral vein thrombosis - A critical review

Cerebral vein thrombosis (CVT) is a rare presentation of venous thromboembolism. Prompt and accurate diagnosis is essential as delayed recognition and treatment may lead to permanent disability or even death. Since no validated diagnostic algorithms exist, the diagnosis of CVT mainly relies on neuroimaging. Digital subtraction angiography (DSA) is the historical diagnostic standard for CVT, but is rarely used nowadays and replaced by computed tomography (CT) and magnetic resonance imaging (MRI). High quality studies to evaluate the diagnostic test characteristics of state of the art imaging modalities are however unavailable to date. This review provides an overview of the best available evidence regarding the diagnostic performance of CT and MRI for the diagnosis of CVT. Notably, available studies are observational, mostly small, outdated, and with a high risk of bias. Therefore, direct comparison between studies is difficult due to large diversity in study design, imaging method, reference standard, patient selection and sample size. In general, contrast-enhanced techniques are more accurate for the diagnosis of CVT then non-contrast-enhanced techniques. CT venography and MRI have been both reported to be adequate for establishing a final diagnosis of CVT, but choice of modality as used in clinical practice depends on availability, local preference and experience, as well as patient characteristics. Our review underlines the need for high-quality diagnostic studies comparing CT venography and MRI in specific settings, to improve clinical care and standardize clinical trials.

Cerebral and Splanchnic Vein Thrombosis: Advances, Challenges, and Unanswered Questions

Cerebral vein thrombosis (CVT) and splanchnic vein thrombosis (SVT) are two manifestations of venous thromboembolism (VTE) at unusual sites. They have an incidence at least 25-50 times lower than usual site VTE, but represent true clinical challenges. Recent evidence on the epidemiology, risk factors, prognosis, and treatment of CVT and SVT has been published in the last two decades, thus contributing to a better understanding of these diseases. The improvement in imaging techniques and a higher degree of clinical suspicion may have led to the observed increased frequency, whereas a better knowledge of provoking mechanisms could have contributed to reducing the proportion of events classified as unprovoked or idiopathic (13%-21% of CVT, 15%-27% of SVT). Few small randomized clinical trials and a number of observational studies, although hampered by heterogeneous therapeutic approaches, shed light on the safety and effectiveness of anticoagulant therapy in these populations. However, there are still some grey areas that warrant future research. In this narrative review, we discuss recent advances and therapeutic challenges in CVT and SVT.

Splanchnic Vein Thrombosis: Current Perspectives

Splanchnic vein thrombosis (SVT) including portal, mesenteric, splenic vein thrombosis and the Budd-Chiari syndrome, is a manifestation of unusual site venous thromboembolism. SVT presents with a lower incidence than deep vein thrombosis of the lower limbs and pulmonary embolism, with portal vein thrombosis and Budd-Chiari syndrome being respectively the most and the least common presentations of SVT. SVT is classified as provoked if secondary to a local or systemic risk factor, or unprovoked if the causative trigger cannot be identified. Diagnostic evaluation is often affected by the lack of specificity of clinical manifestations: the presence of one or more risk factors in a patient with a high clinical suspicion may suggest the execution of diagnostic tests. Doppler ultrasonography represents the first line diagnostic tool because of its accuracy and wide availability. Further investigations, such as computed tomography and magnetic resonance angiography, should be executed in case of suspected thrombosis of the mesenteric veins, suspicion of SVT-related complications, or to complete information after Doppler ultrasonography. Once SVT diagnosis is established, a careful patient evaluation should be performed in order to assess the risks and benefits of the anticoagulant therapy and to drive the optimal treatment intensity. Due to the low quality and large heterogeneity of published data, guidance documents and expert opinion could direct therapeutic decision, suggesting which patients to treat, which anticoagulant to use and the duration of treatment.

Approach to thrombosis at unusual sites: Splanchnic and cerebral vein thrombosis

Splanchnic vein thrombosis (SVT) and cerebral vein thrombosis (CVT) are two manifestations of unusual site venous thromboembolism (VTE). SVT includes thrombosis in the portal, mesenteric or splenic veins, and the Budd-Chiari syndrome. CVT encompasses thrombosis of the dural venous sinuses and thrombosis of the cerebral veins. Unusual site VTE often represents a diagnostic and therapeutic challenge because of the heterogeneity in clinical presentation, the limited evidence available in the literature on the acute and long-term prognosis of these diseases, and the lack of large randomized controlled trials evaluating different treatment options. This narrative review describes the approach to patients with SVT or CVT by examining the diagnostic process, the assessment of potential risk factors and the appropriate anticoagulant treatment.