Factor V Leiden mutation is a risk factor for cerebral venous thrombosis: a case-control study of 55 patients

Asymptomatic Postoperative Cerebral Venous Sinus Thrombosis After Posterior Fossa Tumor Surgery: Incidence, Risk Factors, and Therapeutic Options

BACKGROUND

Cerebral venous sinus thrombosis (CVST) is a known complication of posterior fossa surgery near the sigmoid and transverse sinus. The incidence and treatment of postoperative asymptomatic CVST are controversial.

OBJECTIVE

To analyze incidence, risk factors, and management of asymptomatic postoperative CVST after posterior fossa tumor surgery.

METHODS

In this retrospective, single-center study, we included all patients who underwent posterior fossa tumor surgery in the semisitting position between January 2013 and December 2020. All patients underwent preoperative and postoperative imaging using MRI with/without additional computed tomography angiography. We analyzed the effect of demographic and surgical data on the incidence of postoperative CVST. Furthermore, therapeutic anticoagulation or conservative treatment for postoperative CVST and the incidence of intracranial hemorrhage were investigated.

RESULTS

In total, 266 patients were included. Thirty-three of 266 (12.4%) patients developed postoperative CVST. All patients were asymptomatic. Thirteen of 33 patients received therapeutic anticoagulation, and 20 patients did not. Univariate analysis showed that age ( P = .56), sex ( P = .20), American Society of Anesthesiology status ( P = .13), body mass index ( P = .60), and length of surgery ( P = .176) were not statistically correlated with postoperative CVST. Multivariate analysis revealed that meningioma ( P < .001, odds ratio 11.3, CI 95% 4.1-31.2) and vestibular schwannoma ( P = .013, odds ratio 4.4, CI 95% 1.3-16.3) are risk factors for the development of new postoperative CVST. The use of therapeutic anticoagulation to treat postoperative CVST was associated with a higher rate of intracranial hemorrhage (n = 4, P = .017).

CONCLUSION

Tumor entity influences the incidence of postoperative CVST. In clinically asymptomatic patients, careful decision making is necessary whether to initiate therapeutic anticoagulation or not.

An Integrated Approach on the Diagnosis of Cerebral Veins and Dural Sinuses Thrombosis

(1) Objective: This review paper aims to discuss multiple aspects of cerebral venous thrombosis (CVT), including epidemiology, etiology, pathophysiology, and clinical presentation. Different neuroimaging methods for diagnosis of CVT, such as computer tomography CT/CT Venography (CTV), and Magnetic Resonance Imaging (MRI)/MR Venography (MRV) will be presented. (2) Methods: A literature analysis using PubMed and the MEDLINE sub-engine was done using the terms: cerebral venous thrombosis, thrombophilia, and imaging. Different studies concerning risk factors, clinical picture, and imaging signs of patients with CVT were examined. (3) Results: At least one risk factor can be identified in 85% of CVT cases. Searching for a thrombophilic state should be realized for patients with CVT who present a high pretest probability of severe thrombophilia. Two pathophysiological mechanisms contribute to their highly variable clinical presentation: augmentation of venular and capillary pressure, and diminution of cerebrospinal fluid absorption. The clinical spectrum of CVT is frequently non-specific and presents a high level of clinical suspicion. Four major syndromes have been described: isolated intracranial hypertension, seizures, focal neurological abnormalities, and encephalopathy. Cavernous sinus thrombosis is the single CVT that presents a characteristic clinical syndrome. Non-enhanced CT (NECT) of the Head is the most frequently performed imaging study in the emergency department. Features of CVT on NECT can be divided into direct signs (demonstration of dense venous clot within a cerebral vein or a cerebral venous sinus), and more frequently indirect signs (such as cerebral edema, or cerebral venous infarct). CVT diagnosis is confirmed with CTV, directly detecting the venous clot as a filling defect, or MRI/MRV, which also realizes a better description of parenchymal abnormalities. (4) Conclusions: CVT is a relatively rare disorder in the general population and is frequently misdiagnosed upon initial examination. The knowledge of wide clinical aspects and imaging signs will be essential in providing a timely diagnosis.

Prevalence of Inherited Procoagulant States in Cerebral Venous Thrombosis and its Correlation with Severity and Outcome

Background Cerebral venous thrombosis (CVT) is one of the important causes of stroke in young adults. It is caused by complete or partial thrombotic occlusion of the cerebral venous sinuses or cortical veins. There are many risk factors associated with this condition, out of which common ones are oral contraceptives use, genetic, or acquired thrombophilias, infections, malignancy, pregnancy, and puerperium. We aimed to study the prevalence of inherited procoagulant states in patients with CVT and correlate these states with the severity and outcome.

Materials and Methods  It was a prospective observational study of 2 years duration in which 75 patients, 18 to 50 years old, with confirmed CVT were included. The baseline data, imaging findings were recorded for all the patients. After 3 months of the onset of CVT, anticoagulants were stopped and a procoagulant test was done for all patients. Severity was assessed by Glasgow Coma Score (GCS) at the onset of illness. Functional assessments were done using the modified Rankin Scale (mRS) at presentation, at 7 days, 6 weeks, and 3 months.

Results  In the present study, any procoagulant state was seen in 9 out of 75 patients with CVT that accounted for 12% of the total population. There was no significant correlation between the presence of procoagulant states and severity of illness as assessed by GCS at presentation. The presence of any thrombophilia did not affect the final outcome at 7 days, 6 weeks or 3 months ( p  = 0.532, p  = 0.944 and p  = 0.965 respectively) as assessed by modified Rankin Scale (mRS).

Conclusion  Inherited procoagulant states are an important risk factor for CVT. The presence of an inherited procoagulant state does not have any correlation with the disease severity and outcome.

Prothrombotic Factors Have Significant Association with Arterial and Venous Strokes in Indian Tamilians

BACKGROUND

Prothrombotic factors have been correlated with vascular events in young patients, with recurrent strokes, and with venous thromboembolisms. However, their prevalence in adult strokes, in healthy populations, and in specific ethnic groups is not well defined. We investigated the association of prothrombotic factors with strokes in a South Indian Tamil population.

METHODS

In this hospital-based cross-sectional study, plasma homocysteine (Hcys), protein C and protein S activity levels, activated protein C resistance (APCR) as a surrogate for factor V Leiden (FVL), fibrinogen, and antithrombin III (ATIII) were determined from 75 consecutive patients with ischemic stroke (IS), 25 with cortical venous thrombosis (CVT), and 75 healthy control participants. The Student t test or Mann-Whitney U test was used for comparing prothrombotic factor levels between the stroke and control groups. The χ2 or Fisher exact test was used for comparisons of proportions of thrombophilia and estimation of odds ratios. Mid-P correction was done for multiple estimations.

RESULTS

Hcys levels in patients with IS were significantly higher compared with those in healthy control participants (P = 0.02). Proportions of ATIII deficiency and hyperfibrinogenemia were significantly higher in the IS group, and no healthy control participants had hyperfibrinogenemia. Protein C deficiency was more frequent in those with IS (17%; P < 8 × 10-5) and CVT (P < 10-7) compared with healthy control participants, and protein C activity levels (P = 0.016) were also significantly lower in patients with CVT. Other parameters had no significant associations with IS and CVT. The frequency of protein S deficiency was high in healthy control participants (60%) and in both patients with IS (45%; P = 0.1) and patients with CVT (48%; P = 0.4). No patients or control participants had abnormal APCR.

CONCLUSIONS

In Tamilian participants, several prothrombotic factors were associated with IS. Protein C deficiency alone was associated with CVT. Replication of the pattern in genetically linked populations around the world may affect management of stroke in those populations.

Ischemic Infarction in Young Adults: A Review for Radiologists

Ischemic strokes in young adults are devastatingly debilitating and increasingly frequent. Stroke remains the leading cause of serious disability in the United States. The consequences of this familiar disease in this atypical age group are especially detrimental and long lasting. Ischemic stroke in young adults is now emerging as a public health issue, one in which radiologists can play a key role. The incidence of ischemic infarction in young adults has risen over the past couple of decades. Increased public awareness, increased use of MRI and angiography, and more accurate diagnosis may in part explain the increased detection of stroke in young adults. The increased prevalence of stroke risk factors in young adults (especially sedentary lifestyle and hypertension) may also contribute. However, compared with older adults, young adults have fewer ischemic infarcts related to the standard cardiovascular risk factors and large- or small-vessel disease. Instead, their infarcts most commonly result from cardioembolic disease and other demonstrated causes (ie, dissection). Thus, radiologists must expand their differential diagnoses to appropriately diagnose ischemic strokes and identify their causes in the young adult population. From the more frequent cardioembolism and dissection to the less common vasculitis, drug-related, CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy), moyamoya, and hypercoagulable state-related infarcts, this article covers a wide breadth of causes and imaging findings of ischemic stroke in young adults. ^©RSNA, 2019.

Postoperative cerebral venous sinus thrombosis in the setting of surgery adjacent to the major dural venous sinuses

OBJECTIVE

Cerebral venous sinus thrombosis (CVST) is a known complication of surgeries near the major dural venous sinuses. While the majority of CVSTs are asymptomatic, severe sinus thromboses can have devastating consequences. The objective of this study was to prospectively evaluate the true incidence and risk factors associated with postoperative CVST and comment on management strategies.

METHODS

A prospective study of 74 patients who underwent a retrosigmoid, translabyrinthine, or suboccipital approach for posterior fossa tumors, or a supratentorial craniotomy for parasagittal/falcine tumors, was performed. All patients underwent pre- and postoperative imaging to evaluate sinus patency. Demographic, clinical, and operative data were collected. Statistical analysis was performed to identify incidence and risk factors.

RESULTS

Twenty-four (32.4%) of 74 patients had postoperative MR venograms confirming CVST, and all were asymptomatic. No risk factors, including age (p = 0.352), BMI (p = 0.454), sex (p = 0.955), surgical approach (p = 0.909), length of surgery (p = 0.785), fluid balance (p = 0.943), mannitol use (p = 0.136), tumor type (p = 0.46, p = 0.321), or extent of resection (p = 0.253), were statistically correlated with thrombosis. All patients were treated conservatively, with only 1 patient receiving intravenous fluids. There were no instances of venous infarctions, hemorrhages, or neurological deficits. The rate of CSF leakage was significantly higher in the thrombosis group than in the nonthrombosis group (p = 0.01).

CONCLUSIONS

This prospective study shows that the radiographic incidence of postoperative CVST is higher than that previously reported in retrospective studies. In the absence of symptoms, these thromboses can be treated conservatively. While no risk factors were identified, there may be an association between postoperative CVST and CSF leak.

Factor V Leiden, factor V Cambridge, factor II GA20210, and methylenetetrahydrofolate reductase in cerebral venous and sinus thrombosis: A case-control study

Background:

Factor V G1691A (FV Leiden), FII GA20210, and methylenetetrahydrofolate reductase (MTHFR) C677T mutations are the most common genetic risk factors for thromboembolism in the Western countries. However, there is rare data in Iran about cerebral venous and sinus thrombosis (CVST) patients. The aim of this study was to evaluate the frequency of common genetic thrombophilic factors in CVST patients.

Materials and Methods:

Forty consequently CVST patients from two University Hospital in Isfahan University of Medical Sciences aged more than 15 years from January 2009 to January 2011 were recruited. In parallel, 51 healthy subjects with the same age and race from similar population selected as controls. FV Leiden, FII GA20210, MTHFR C677T, and FV Cambridge gene mutations by polymerase chain reaction technique were evaluated in case and control groups.

Results:

FV Leiden, FII GA20210, and FV Cambridge gene mutations had very low prevalence in both case (5%, 2%, 0%) and control (2.5%, 0%, 0%) and were not found any significant difference between groups. MTHFR C677T mutations was in 22 (55%) of patients in case group and 18 (35.5%) of control group (P = 0.09).

Conclusion:

This study showed that the prevalence of FV Leiden, FII GA20210, and FV Cambridge were low. Laboratory investigations of these mutations as a routine test for all patients with CVST may not be cost benefit.

Risk factors and recurrent thrombotic episodes in patients with cerebral venous thrombosis

BACKGROUND

The prevalence of thrombophilic abnormalities in patients with cerebral vein thrombosis has been reported to be similar to that in patients with deep vein thrombosis of the lower limb. The role of gender-specific risk factors (pregnancy, oral contraceptives) is well established, whereas that of other acquired risk conditions is debated.

MATERIALS AND METHODS

We screened 56 patients with cerebral vein thrombosis and 184 age- and sex-matched apparently healthy controls for prothrombin (factor II, FII) G20210A and factor V Leiden polymorphisms; protein S, protein C, and antithrombin deficiency; anticardiolipin antibodies; hyperhomocysteinaemia and other putative risk factors.

RESULTS

The G20210A polymorphism was found in 29.1% of patients and in 5.7% of controls (odds ratio [OR] 7.1; P<0.0001; adjusted OR 12.67, P<0.0001). Frequencies of factor V Leiden and hyperhomocysteinaemia were not significantly different in patients and controls, nor were the other thrombophilic tests and some established cardiovascular risk factors, such as smoking, obesity or overweight and arterial hypertension. Conversely, 53.7% of the women who developed cerebral vein thrombosis did so while assuming oral contraceptives (OR 6.12; P<0.0001), with a further increase of risk in FII G20210A carriers (OR 48.533). Some associated diseases (onco-haematological disorders and infections) also had a significant role. Over a median 7-year follow-up, irrespective of the duration of antithrombotic treatment, 9/56 (16%) patients had further episodes of venous/arterial thrombosis. No significant risk factor for recurrent thrombosis was identified.

DISCUSSION

In spite of the limitations of the sample size, our data confirm the role of FII G20210A mutation in this setting and its interactions with acquired risk factors such as oral contraceptives, also highlighting the risk of recurrent thrombosis in cerebral vein thrombosis patients.

A prospective cohort study on patients treated with anticoagulants for cerebral vein thrombosis

OBJECTIVES

Cerebral vein thrombosis (CVT) is a potentially fatal disorder for which treatment guidelines are scanty. To assess the short- and long-term benefit of anticoagulant therapy, we performed a prospective cohort study on CVT patients.

METHODS

Forty-four consecutive CVT patients received conventional anticoagulation with heparin followed by warfarin for at least 3 months. Patients presenting with symptoms suggestive of pulmonary embolism (PE) underwent confirmatory objective tests. Acquired or inherited risk factors for thrombosis were investigated in all patients. Thrombotic and hemorrhagic events occurring during treatment, and the long-term outcome using the modified Rankin Scale (mRS) were recorded.

RESULTS

Congenital and/or acquired conditions predisposing to thrombosis were detected in 37 patients (84.1%), with a high prevalence of oral contraceptive use (66.7% of females) and thrombophilia (31.8%); more than one risk factor was seen in 31.8% of cases. At referral, six patients (13.6%) presented with symptoms of PE, which was confirmed in all. During the initial treatment period, two patients (4.5%) developed symptomatic progression of CVT, which was fatal in 1, and 2 (4.5%) developed major bleeding complications. A favorable outcome (mRS 0-2) at 6-12 months was recorded in 37 of the 43 patients who survived the acute phase (86%).

CONCLUSIONS

The outcome of CVT patients managed with conventional anticoagulation who survive the initial phase is favorable in the vast majority. The prevalence of concomitant PE is considerably high, supporting the need of anticoagulant therapy.

Cerebral venous thrombosis associated with homozygous factor V Leiden mutation in a 15-year-old girl of Tunisian origin

Cerebral venous thrombosis (CVT) is a rare disease. It has numerous and complex etiologies. Inherited or acquired prothrombotic states play a key role in the development of this disease, such as factor V G1691A mutation (FV Leiden). A 15-year-old girl presented to the Department of Neurology with a complaint of severe headache with visual blurring. The diagnosis of CVT was not initially suspected because of the patient's condition on presentation. An MRI showed thrombosis in the superior sagittal sinus, confirming venous stroke. Anticardiolipin and antiphospholipid antibodies were assessed. In addition, inherited prothrombotic defects, such as protein C, protein S, and antithrombin deficiencies, and genetic mutations for FV Leiden, prothrombin gene G20210A (FII G20210A), and methyltetrahydrofolate reductase C677T (MTHFR C677T) were studied. All results were unremarkable except for the unique homozygous FV Leiden mutation, which likely contributed to this prothrombotic situation. This study highlights the fact that FV Leiden may play a significant role in the onset of CVT in young patients.

The risk of venous thrombosis, including cerebral vein thrombosis, among women with thrombophilia and oral contraceptive use: a meta-analysis

Several small studies have reported an elevated risk of venous thrombosis (VT) with thrombophilia and oral contraceptive (OCP) use. We aimed to summarize the risk of VT among women with thrombophilia and OCP use and to assess the interaction between the 2 factors. We selected 15 studies that assessed the prevalence of OCP use and thrombophilia among reproductive-aged women. Odds ratios (ORs) were calculated for each study and pooled using the random effects model. We found an increased risk of VT among women with OCP use (pooled OR 3.0, 95% confidence interval [CI] 1.9-4.5) and with thrombophilia (pooled OR 4.5, CI 3.4-5.9), respectively. Heterogeneity was significant (I (2) >80%). Women with both thrombophilia and OCP use had a 14-fold risk of VT compared to healthy OCP nonusers (pooled OR 14.25, CI 6.2-32.8). Oral contraceptive use and thrombophilia similarly increase VT risk. Our study confirms an interaction between OCP use and thrombophilia.

Thrombophilic screening in young patients (< 40 years) with idiopathic ischemic stroke: a controlled study

INTRODUCTION

Despite extensive clinical and laboratory investigations, the etiology of ischemic stroke remains unknown in approximately one third of patients.

MATERIALS AND METHODS

Thirty-four consecutive patients less than 40 years old (Males 13, Females 21, mean age 26.6 years, range 2-39) with documented ischemic stroke underwent, one year after the acute event, laboratory evaluation of antithrombin, protein C, free and total protein S, activated protein C resistance, fibrinogen, factor VII:C, homocysteine levels and antiphospholipid antibodies (APA). Moreover, prevalence of F5 R506Q, F2 G2021A and homozygosis for thermolabile variant C677T of the methylenetetrahydrofolate reductase (MTHFR) were also evaluated and compared to the results obtained in 120 normal controls.

RESULTS

Antithrombin and protein C levels resulted normal in all cases. One patient (2.9%) showed free protein S deficiency and 3 patients (8.8%) had activated protein C resistance. Homocysteine levels above 15 μmol/L were found in one patient (2.9%). APA were found in 21 patients (61.7%) and in only 2 out of 120 (1.66%) controls (OR=95.31; 95% C.I.: 18.22-667.81). The multivariate analysis selected that the presence of APA was significantly associated with an increased risk of stroke (OR=156.60; 95% C.I.: 25.99-943.47) in this cohort of patients. The combination between APA and cardiovascular risk factors determined a risk of 29-fold (OR=29.31; 95% CI: 3.28-261.69).

DISCUSSION

Our data suggest that the presence of APA is associated with an increased risk of idiopathic ischemic stroke in young patients. Furthermore, also the combination of APA and cardiovascular risk factors is significantly associated with development of idiopathic ischemic stroke.

Genetics and genomics of stroke: novel approaches

Evidence for a genetic basis for stroke comes from twin and family studies and from the occurrence of a number of uncommon monogenic disorders, but the contribution of genetic factors identified for stroke so far is small. Advances in genetics and genomics may permit new insights. In recent genome-wide association studies, a number of single-nucleotide polymorphisms have been associated with specific stroke subtypes and major stroke risk factors such as diabetes and atrial fibrillation. These await replication. Studies of messenger ribonucleic acid expression have also shown promise for the development of genomic signatures for stroke classification. Stroke and coronary heart disease share some features of pathophysiology, risk, and treatment, and their genetic and genomic bases also appear to overlap.

MTHFR C677T, FII G20210A, FV Leiden G1691A, NOS3 Intron 4 Vntr, and APOE ε4 Gene Polymorphisms are Not Associated with Spontaneous Cervical Artery Dissection

Aims

The pathogenesis of spontaneous cervical artery dissection remains unknown. We examined the association between different polymorphisms frequently found in young patients with cryptogenic stroke [methylenetetrahydrofolate reductase ( MTHFR) C677T, factor II (prothrombin) G20210A, factor V G1691A (Leiden), nitric oxide synthase 3 ( NOS3) intron 4 VNTR, and apolipoprotein E ( APOE) ε4 gene] in patients with a cerebral infarct caused by spontaneous cervical artery dissection.

Methods

Forty-eight patients (27 males) and 96 matching control subjects were recruited. Clinical history, including cardiovascular risk factors, was assessed in all subjects. Genotypes were determined by a polymerase chain reaction with and without a restriction fragment length polymorphism. The genotypes and allele frequencies of the five genetic variants studied were compared between spontaneous cervical artery dissection cases and controls. We also incorporated our data into a meta-analysis of the MTHFR/C677T variant.

Results

Of 48 patients with spontaneous cervical artery dissection (28 vertebral and 20 carotid), the mean age of the patients was 36·6 ± SD 9·9 years. There were no significant associations between the alleles of the five genetic polymorphisms studied and spontaneous cervical artery dissection. In the meta-analysis of the MTHFR/C677T variant, a total of 564 individuals (231 cases and 333 controls) were analysed; no significant association was observed. Conclusions The results from this exploratory case-control study show the lack of an association between MTHFR, factor II G20210A, factor V G1691A, NOS3, intron 4 VNTR, and APOE ε4 gene polymorphisms and the development of spontaneous cervical artery dissection. Our findings contribute towards a better understanding of the genetic risk factors associated with spontaneous cervical artery dissection.

Cerebral venous and sinus thrombosis and thrombophilic mutations in Western Iran: association with factor V Leiden

The present study aimed at investigating the prevalence of factor V Leiden G1691A, prothrombin G20210A, and MTHFR C677T in cerebral venous and sinus thrombosis (CVST) patients and their possible association with CVST in Western Iran. A total of 24 CVST patients with the mean age of 37.1 +/- 11.7 years and 100 sex- and age-matched healthy individuals from Kermanshah Province of Iran with ethnic background of Kurd were studied for factor V Leiden G1691A, prothrombin G20210A and MTHFR C677T by PCR-RFLP method using Mnl I, Hind III, and Hinf I restriction enzymes, respectively. Prevalence of factor V Leiden was 16.7% in patients and 2% in control group. A significant association was found between factor V Leiden mutation and CVST with odds ratio (OR) of 9.8 (95% confidence intervals [CI] 1.68-57.2, P = .01). No prothrombin G20210A was found among patients. In patients, MTHFR C677T tended to be higher (58.3%) compared to control (44%), OR of 1.8 (95% CI 0.73-4.5, P = .2). Our study for the first time has determined the prevalence of inherited thrombophilia in a homogenous ethnic group of CVST patients and suggests that factor V Leiden, and not the prothrombin gene mutation is a risk factor for CVST in Western Iran.

THROMBOPHILIC RISK FACTORS IN PATIENTS WITH CRANIAL AND SPINAL DURAL ARTERIOVENOUS FISTULAE

OBJECTIVE

Numerous studies have reported the technical aspects and results of surgical and/or endovascular treatment of cranial dural arteriovenous fistulae (cDAVF) and spinal dural arteriovenous fistulae (sDAVF). Only a few of them have addressed the question of thrombophilic conditions, which may be relevant as pathogenetic factors or can increase the risk for venous thromboembolic events. Therefore, the objective of this study is to compare thrombophilic risk factors in patients with cDAVF and sDAVF with no history of trauma.

METHODS

A total of 43 patients (25 with cDAVF and 18 with sDAVF) were included in this study. Blood samples were analyzed for G20210A mutation of the prothrombin gene and factor V Leiden mutation. In all patients, prothrombin time, international normalized ratio, fibrinogen, antithrombin, protein C and S activity, von Willebrand factor antigen, ristocetin cofactor activity, D-dimer, coagulation factor VIII activity, and tissue factor pathway inhibitor were determined. Screening was performed for the occurrence of lupus antiphospholipid and cardiolipin antibodies.

RESULTS

The prevalence of G20210A mutation of the prothrombin gene was significantly higher in patients with cDAVF (n = 6) compared with patients with sDAVF (n = 0; P &lt; 0.05, Fisher's exact test). A factor V Leiden mutation was found in 3 patients with sDAVF and in 1 patient with cDAVF (P = 0.29, Fisher's exact test). No significant difference was found for other parameters, except for fibrinogen, but decreased protein C activity was more frequent in patients with cDAVF compared with patients with sDAVF (4 versus 1). Decreased protein S activity was encountered in 3 patients (2 with sDAVF and 1 with cDAVF). Cardiolipin antibodies were found in 2 patients with cDAVF but in none with sDAVF, whereas only 1 patient with sDAVF had lupus antiphospholipid antibodies.

CONCLUSION

In both groups of patients with dural arteriovenous fistulae, genetic thrombophilic abnormalities occurred in a higher percentage than in the general population. The differences of the genetic abnormalities may be involved in different pathophysiological mechanism(s) in the development of these distinct neurovascular entities.

The G79A polymorphism of protein Z gene is an independent risk factor for cerebral venous thrombosis

BACKGROUND AND PURPOSE

Protein Z (PZ), a vitamin Kdependent protein, plays a role in inhibiting coagulation. Its plasma level or PZ gene polymorphisms have been discussed as risk factors for stroke with conflicting results reported between various studies. Only one of these polymorphisms was studied in a cohort of patients suffering from cerebral venous thrombosis (CVT).

METHODS

We performed a retrospective genetic study comparing 100 healthy controls to 54 patients referred to our hemostasis unit after CVT occurrence. We compared the distribution of three PZ gene polymorphisms that may influence PZ plasma levels: A-13G in the promoter and G79A in intron F were tested using previously described techniques, and we developed a technique to evaluate the G-103A in intron A.

RESULTS

The G79A polymorphism was significantly more frequent in patients than in controls (p = 0.012): the presence of at least one A allele led to an odds ratio of 2.57 with a 95 % confidence interval of 1.23-5.34. The A-13G polymorphism also showed a nonsignificant trend towards a higher prevalence in patients.

CONCLUSION

The G79A polymorphism of the PZ gene was shown to be a new independent risk factor for cerebral venous thrombosis. Nevertheless, these results have to be confirmed by a prospective study including plasma PZ evaluation.

Hypercoagulation Testing in Ischemic Stroke

Context.—The utility of laboratory testing for hypercoagulability in the setting of stroke is uncertain.

Objective.—To review the current literature and to make recommendations with regard to laboratory testing for various hypercoagulability risk factors for ischemic stroke.

Data Sources.—Published articles studying the utility of various hypercoagulation tests in predicting initial and/or recurrent stroke or transient ischemic attack as well as cerebral vein thrombosis were collected and reviewed, with an emphasis on prospective studies.

Conclusions.—Certain tests, such as C-reactive protein, homocysteine, antiphospholipid antibodies, and lipoprotein(a), may be useful in patients with a history of stroke or at high risk for stroke, as evidenced by prospective data. Factor V Leiden, prothrombin G20210A, protein C, protein S, and antithrombin are not recommended for routine testing but may be useful in certain populations, such as in pediatric patients or in patients with cerebral vein thrombosis.

Trombofilia genética y trombosis de senos venosos cerebrales

BACKGROUND AND OBJECTIVE

Sinus cerebral venous thrombosis (SCVT) is an unfrequent disease, with variable clinical presentation and prognosis. The objective of this study was to analyze the relationship between factor V Leiden, prothrombin G20210A mutation (PT 20210A) and MTHR and SCVT.

PATIENTS AND METHOD

Cases and control study including 15 patients with diagnosis of SCVT. We performed a genetic analysis of the mutation of factor V Leiden, the PT G20210A and the C677T of the MTHR.

RESULTS

Factor V Leiden: 26.6% heterozygote in cases and only 8.3% in control group, thus showing odds ratio [OR] = 4,0. Mutation 20210A of the prothrombin: in patients, 13.3% of heterozygote, while a 6,6% in controls, finding an OR = 2.1 (95% confidence interval [CI], 1.67-10.04). Mutation of the MTHR: 40% heterozygote and 20% homozygote in patients group respect to 51.6% and 6,9%, respectively, in the control group, but no statistical differences were found.

CONCLUSIONS

The presence of factor V Leiden and PT 20210A are risk factors for SCVT, but not the mutation of the MTHR.

Thromboses veineuses cérébrales

Venous thromboses in the cerebrum are rare, within the context of both cerebrovascular disease and all of the venous thrombotic diseases. Its clinical aspects are polymorphic in their onset and in their acute phase, making diagnosis difficult. MRI with angiographic sequences can show the presence of a thrombus within a venous vessel and its consequences on the cerebral parenchyma. Hemostatic disorders are the leading causes of cerebral venous thrombosis, in particular, constitutional thrombophilia often associated with one or several promoting factors such as use of oral contraception. This explains the incidence peak among young women. The cause of approximately 20% of cerebral venous thromboses is never identified. Antithrombotic treatment must be prescribed on an emergency basis when the diagnosis is made, even if potentially hemorrhagic lesions are also present. The risk of permanent neurologic damage is approximately 13%.

Postoperative dural sinus thrombosis in a patient in a hypercoagulable state

✓ 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.

Thrombophilic gene polymorphisms in puerperal cerebral veno-sinus thrombosis

Puerperal cerebral veno-sinus thrombosis (PCVT) is a common form of stroke in young women in India, which is associated with high morbidity and mortality. The frequency of PCVT in India is 10 to 12 times more compared to western population. As yet, the etiology of this condition is unclear. Our aim was to study the prevalence and the role of the common genetic polymorphisms associated with thrombophilia such as factor V Leiden, prothrombin G20210A and methylene tetrahydrofolate reductase (MTHFR) C677T, in aseptic PCVT. We investigated 86 women with PCVT and 86 age-matched women with no post-partum complications. Polymerase chain reaction (PCR)/restriction fragment length polymorphism analysis was used to identify their genotypes. The frequency of the three polymorphisms in cases and controls were: factor V Leiden, 2.3% versus 1.2% (OR 0.49, 95% CI=0.02-7.12, p=1.000) and MTHFR C677T, 16.3% versus 17.4% (OR 0.92, 95% CI=0.39-2.19, p=0.838). The prothrombin G20210A variant was not detected in either patients or controls. The clinical characteristics of the PCVT patients with the polymorphisms did not differ significantly from those without them. In our series of PCVT patients, the risk associated with the established thrombophilic risk factors is insignificant. Exploration of these gene polymorphisms seems to be of limited value in the investigation of PCVT in south Indian women.

Factor V Leiden and increased risk for arterial thrombotic disease in young Brazilian patients

The contribution of mutations in the prothrombin (FII G20210A), methylenetetrahydrofolate reductase (C677T) genes and factor V Leiden (FVL) to the pathogenesis of arterial thrombosis remains controversial. In this study, these polymorphisms were investigated by polymerase chain reaction-restriction fragment length polymorphism in a group of 53 patients that presented arterial thrombosis other than myocardial infarction as a first thrombotic event and 275 control subjects living in the state of Minas Gerais, Brazil. Odds ratio (OR) and chi tests were applied for statistical comparisons. Similar frequencies were detected among patients and control subjects for the C677T mutation. The 20210A mutation was present in 3.6% of the control subjects but was not detected among ischemic stroke patients. Significant differences were detected only for factor V Leiden (odds ratio 7.11; 95% confidence interval 1.55-32.73). Our data indicate that, among these genetic factors, factor V Leiden was identified as an important risk factor for arterial thrombosis in this group of patients. In addition, our results indicate regional differences in the incidence of these genetic factors in Brazil, as compared to the incidences reported in other studies.

Cerebral venous thrombosis: a review

BACKGROUND

Cerebral venous thrombosis (CVT) is less frequent than arterial thrombosis, presents in an atypical fashion, and is an uncommon cause of stroke. Although the functional outcome from CVT is better than arterial strokes, the outcome of CVT remains unpredictable and may lead to sequelae or even death if not recognized and treated early.

REVIEW SUMMARY

The clinical presentations, time of onset, and neuroimaging findings vary. Symptoms include headache, seizures, neurologic deficits, and altered consciousness. Causes include hematologic disorders, hypercoagulable states, pregnancy, and contraceptive medications. Treatment of this infrequent condition remains controversial and includes heparin infusions, intrasinus thrombolysis, and other endovascular procedures.

CONCLUSION

Further clinical trials are needed to address optimal treatment of this infrequent but potentially serious condition.

Thrombophilic abnormalities, oral contraceptives, and risk of cerebral vein thrombosis: a meta-analysis

Recent studies suggest that thrombophilic abnormalities and the use of oral contraceptives (OCs) are the leading causes of cerebral vein thrombosis (CVT). The purpose of this study was to assess the association between CVT and thrombophilic states, OCs, and their interaction. For data sources, we used the MEDLINE, EMBASE, and Cochrane Library databases (January 1994 to March 2005), reference lists of retrieved articles, and contact with content experts. We selected studies comparing the prevalence of OC use and the prevalence of prothrombitic abnormalities in patients with CVT compared with healthy controls. Two reviewers independently selected studies and extracted study characteristics, quality, and outcomes. Odds ratios (ORs) were calculated for each trial and pooled using the Mantel-Haenszel method. Seventeen studies were included. There was an increased risk of CVT in patients using OCs (OR 5.59; 95% confidence interval [CI] 3.95 to 7.91; P < .001), and in patients with factor V Leiden (OR 3.38; 95% CI 2.27 to 5.05; P < .001), with mutation G20 210A of prothrombin (OR 9.27; 95% CI 5.85 to 14.67; P < .001) and with hyperhomocysteinemia (OR 4.07; 95% CI 2.54 to 6.52; P < .001). We concluded that OC users, and patients with factor V Leiden, the prothrombin G20 120A mutation, and hyperhomocysteinemia are at a significantly increased risk of CVT.

Association of the protein C promoter CG haplotype and the factor II G20210A mutation is a risk factor for cerebral venous thrombosis

The factor II G20210A mutation and estrogen treatment are described as risk factors for cerebral venous thrombosis (CVT). We evaluated these known risk factors in a population of CVT patients and investigated the role of a combination of two polymorphisms in the promoter of the protein C gene (PC promoter CG haplotype), newly described as risk factors for deep venous thrombosis. A retrospective population of 26 CVT patients was compared with a control group of 84 healthy volunteers. After a multivariate analysis, we confirmed that the factor II G20210A mutation is an independent risk factor for CVT with odds ratio 4.7 (95% confidence interval, 2.83--75.3). We demonstrated that the CVT risk is increased when this mutation is associated either with the PC promoter CG haplotype (odds ratio=19.8; 95% confidence interval, 2.1--186.5) or, in females, with an estrogen treatment (odds ratio=24; 95% confidence interval, 2.26--127.3). In this work, the association of the factor II G20210A mutation and the PC promoter CG haplotype or estrogen treatment seems to be a particular risk for CVT.

Risk of cerebral venous thrombosis and novel gene polymorphisms of the coagulation and fibrinolytic systems

BACKGROUND AND PURPOSE

Genetic thrombophilic conditions such as those associated with Factor V Leiden (FVL) and the prothrombin mutant (PT G20210A) have been identified as risk factors for cerebral venous thrombosis (CVT). Recently, a single nucleotide polymorphism (SNP) of the thrombin activatable fibrinolysis inhibitor (TAFI G-438A) has been shown to be associated with lower TAFI levels and to decrease the risk for peripheral venous thrombosis. Furthermore, a protective role in juvenile stroke was shown for a SNP of the vitamin K dependent protein Z (PZ Intron F G79A) which is linked with low PZ levels.

PATIENTS AND METHODS

In 77 consecutive patients with CVT and in 203 randomly selected population controls from the same region of Southern Germany, we investigated the following functional SNPs using PCR and restriction fragment analysis techniques: TAFI G-438A, PZ Intron F G79A, FVL and PT G20210A.

RESULTS

The prevalence of FVL tended to be higher (OR 2.08, 95 % CI 0.91-4.75, p = 0.06) and that of PT G20210A (OR 4.57, 95 % CI 1.45-14.44, p = 0.007) was significantly higher in patients with CVT than in controls. The A-allele frequency of the TAFI G-438A polymorphism did not significantly differ between patients (21.3 %) and controls (26.9%; OR 0.71, 95 % CI 0.45-1.12; p = 0.17). For the PZ G79A SNP, the frequency of the A-allele was 19.5% in CVT and 24.6% in controls (OR 0.77, 95 % CI 0.49-1.21; p = 0.31).

CONCLUSIONS

In this large series of CVT patients, a positive association with established thrombophilic risk factors FVL and especially the PT G20210A mutation was confirmed. In contrast, our study found no significant association of CVT with SNPs of the TAFI and the PZ genes. Other than testing for FVL and the PT G20210A mutation, exploration of these potential thrombophilic variants seems to be of limited value in the investigation of CVT.

Prothrombin 20210A and Oral Contraceptive Use as Risk Factors for Cerebral Venous Thrombosis

BACKGROUND

This study investigates the association between cerebral vein thrombosis (CVT) and the mutations FV 1691A (factor V Leiden), PT 20210A and MTHFR 677TT and acquired factors including oral contraceptive (OC) use.

METHODS

26 patients (21 females) and 217 healthy controls (134 females) were studied. Multiple regression analysis was performed.

RESULTS

The frequency of the three mutations in cases and controls were: PT 20210A, 23 versus 1%, odds ratio (OR) 21.40 (95% CI 4.29-118.75), p < 0.001; FV 1691A, 8 versus 1%, OR 5.94 (95% CI 0.66-46.9); MTHFR 677TT, 4 versus 7%, OR 0.54 (95% CI 0.03-4.08). OC use was more frequent in female patients over 14 years old than in controls (84 vs. 40%, OR 8.15, 95% CI 2.09-37.13, p < 0.001). The model that best explained the thrombotic risk included PT 20210A and OC use.

CONCLUSIONS

PT 20210A and OC use are the main thrombophilic risk factors predisposing to CVT and should be routinely investigated in patients with this disease.

Oral contraceptive induced cerebral venous thrombosis treated by local catheter directed thrombolysis

SUMMARY

We report on a case of cerebral venous thrombosis (CVT) induced by oral contraception (OC) activated coagulopathy and its endovascular treatment. Deep venous system and dural sinuses thrombosis complicated with severe neurological deficit and coma due to right thalamic edema and ischemia in a young woman was treated by local thrombolysis with an administration of 0.6 mg/h of the rtPA and the concomitant intravenous unfractioned heparin infusion (700 IU/h). 3D-Xra digital rotational venography performed at the beginning and after treatment confirmed thrombus resolution with rapid flow restoration. Dynamic flow imaging gives interesting information on the deep venous system and the cortical venous collectors drainage. Final NIHSS (National Institute of Health Stroke Scale) and mRS (modified Rankin Scale) confirmed an excellent clinical outcome of the interventional therapy.

Idiopathic intracranial hypertension

OBJECTIVE

The history, diagnosis, and therapy of idiopathic intracranial hypertension (IIH) (pseudotumor cerebri) are reviewed. Theories of pathogenesis are considered, the clinical presentation is described, and potential diagnostic and therapeutic challenges are explored.

METHODS

An extensive literature review of IIH and related conditions (secondary pseudotumor syndromes) was performed. The history of and rationale for the diagnosis and medical and surgical approaches to treatment are reviewed. Available outcome studies are presented.

RESULTS

Diagnosis of IIH requires that the modified Dandy criteria be satisfied. Multiple potential contributing causes of intracranial hypertension must be identified or excluded. The clinical presentation most often includes headaches and papilledema, but many other findings have been described. The most important goal of therapy is to prevent or arrest progressive visual loss. Medical therapies include alleviation of associated systemic diseases, discontinuation of contributing medications, provision of carbonic anhydrase inhibitors, and weight loss. Surgical therapies include lumboperitoneal shunting, ventriculoperitoneal shunting, and optic nerve sheath fenestration. On the basis of the advantages and disadvantages of these treatment modalities, a suggested treatment paradigm is presented.

CONCLUSION

Idiopathic intracranial hypertension is the term to be adopted instead of pseudotumor cerebri. IIH remains an enigmatic diagnosis of exclusion. However, prompt diagnosis and thorough evaluation and treatment are crucial for preventing visual loss and improving associated symptoms.

Hyperhomocysteinemia and other thrombophilic risk factors in 26 patients with cerebral venous thrombosis

Despite the continuous description of new conditions pre-disposing for cerebral venous thrombosis (CVT), no apparent cause is found in about 30% of cases. Hyperhomocysteinemia (hyper-Hcy) is an established risk factor for deep venous thrombosis and stroke but has not been clearly associated with increased risk of CVT. We assessed the prevalence of hyper-Hcy and other thrombophilic risk factors in a population of 26 consecutive patients with non-pyogenic CVT, by review of a prospectively maintained database. The prevalences of hyper-Hcy and prothrombin G20210A, factor V G1691A and methylenetetrahydrofolate reductase (MTHFR) C677T mutations in these patients were compared with those in 100 healthy controls and 100 patients with cerebroarterial disease. The prevalence of hyper-Hcy was greater in patients with CVT (10/26, 38.5%) than healthy controls (13/100; OR 4.18, 95% CI 1.58-11.16) and comparable with that in patients with cerebroarterial disease (42/100). No significant differences were found in the prevalences of prothrombin or MTHFR mutation. No factor V mutation was found. Our findings indicate that hyper-Hcy is associated with an increased risk of CVT. Additional prospective cohort studies on large series of patients are required to clarify the time relationship between hyper-Hcy and the thrombotic event.