Susanna M. Zuurbier

The Incidence of Cerebral Venous Thrombosis A Cross-Sectional Study

Background and Purpose— The purpose of this study was to determine the incidence of adult cerebral venous thrombosis. Methods— A retrospective cross-sectional study was conducted among all 19 hospitals located in 2 Dutch provinces serving 3.1 million people. Adult cerebral venous thrombosis cases diagnosed between January 1, 2008, and December 31, 2010, were identified using the Dutch financial coding system for hospital care and the International Classification of Diseases, 9th Revision. Medical records of potential patients were hand searched to identify cerebral venous thrombosis cases. The Dutch National Bureau for Statistics provided population figures of the 2 provinces during 2008 to 2010. Results— Among 9270 potential cases, we identified 147 patients diagnosed with cerebral venous thrombosis. Of these, 53 patients did not meet the inclusion criteria; therefore, 94 patients were included in the analysis. The overall incidence was 1.32 per 100 000 person-years (95% CI, 1.06–1.61). Among women between the ages of 31 and 50 years, the incidence was 2.78 (95% CI, 1.98–3.82). Conclusions— The incidence of cerebral venous thrombosis among adults is probably higher than previously believed.

Thrombolysis or Anticoagulation for Cerebral Venous Thrombosis: Rationale and Design of the TO-ACT Trial

Rationale Endovascular thrombolysis, with or without mechanical clot removal, may be beneficial for a subgroup of patients with cerebral venous sinus thrombosis (CVT) who have a poor prognosis despite treatment with heparin. Published experience with endovascular thrombolysis is promising but only based on case series and not on controlled trials. Aim The objective of the Thrombolysis or Anticoagulation for Cerebral Venous Thrombosis (TO-ACT) trial is to determine if endovascular thrombolysis improves the functional outcome of patients with a severe form of CVT. Design The TO-ACT trial is a multicenter, prospective, randomized, open-label, blinded endpoint trial. Patients are eligible if they have a radiologically proven CVT, a high probability of poor outcome (defined by presence of one or more of the following risk factors: mental status disorder, coma, intracranial hemorrhagic lesion, or thrombosis of the deep cerebral venous system), and if the responsible physician is uncertain if endovascular thrombolysis or standard anticoagulant treatment is better. One hundred sixty-four patients (82 in each treatment arm) will be included to detect a 50% relative reduction (from 40% to 20%) of poor outcomes. Study Patients will be randomized to receive either endovascular thrombolysis or standard therapy (therapeutic doses of heparin). Endovascular thrombolysis is composed of local application of rt-plasminogen activator (PA) or urokinase within the thrombosed sinuses, mechanical thrombosuction, or a combination of both. Patients randomized to endovascular thrombolysis will be treated with heparin before and after the interventional procedure, according to international guidelines. Outcomes The primary endpoint is the modified Rankin score (mRS) at 12 months, with a score ≥2 defined as poor outcome. Secondary outcomes are six-months mRS, mortality, and recanalization rate. Major intracranial and extracranial hemorrhagic complications within one-week after the intervention are the principal safety outcomes. Results will be analyzed according to the ‘intention-to-treat’ principle. Blinded assessors not involved in the treatment of the patient will assess endpoints with standardized questionnaires.

Declining Mortality in Cerebral Venous Thrombosis A Systematic Review

Background and Purpose— Cerebral venous thrombosis (CVT) is nowadays considered a disease with a good outcome in most cases, but in the past, these patients were thought to have a grave prognosis. We systematically studied the apparent decline in mortality of patients with CVT over time. Methods— A systematic review of the literature (MEDLINE and EMBASE) was performed. Studies with ≥40 patients with CVT that reported mortality at discharge or follow-up were eligible. Duplicate publications based on the same patient cohort were excluded. Studies were ranked according to the year halfway the period of patient inclusion. Two of the authors independently screened all eligible studies. Results— We screened 4585 potentially eligible studies, of which 74 fulfilled the selection criteria. The number of patients per study varied from 40 to 706 (median, 76). Data from 8829 patients with CVT, included from 1942 to 2012, were analyzed. The average age was 32.9 years, and 64.7% were women. There was a significant inverse correlation between mortality and year of patient recruitment (Pearson correlation coefficient, −0.72; P<0.001). In a sensitivity analysis, the correlation remained significant after exclusion of studies published before 1990, retrospective studies, or single-center studies. Both the frequency of focal neurological deficits and coma also decreased significantly over time (correlation coefficient, −0.50 and −0.52). Conclusions— There is a clear trend in declining mortality among patients with CVT over time. Possible explanations are improvements in treatment, a shift in risk factors, and, most importantly, the identification of less severe cases by improved diagnostic methods.

Mechanical Thrombectomy in Cerebral Venous Thrombosis: Systematic Review of 185 Cases

Background and Purpose— Cerebral venous thrombosis is generally treated with anticoagulation. However, some patients do not respond to medical therapy and these might benefit from mechanical thrombectomy. The aim of this study was to gain a better understanding of the efficacy and safety of mechanical thrombectomy in patients with cerebral venous thrombosis, by performing a systematic review of the literature. Methods— We identified studies published between January 1995 and February 2014 from PubMed and Ovid. We included all cases of cerebral venous thrombosis in whom mechanical thrombectomy was performed with or without intrasinus thrombolysis. Good outcome was defined as normal or mild neurological deficits at discharge (modified Rankin Scale, 0–2). Secondary outcome variables included periprocedural complications and recanalization rates. Results— Our study included 42 studies (185 patients). Sixty percent of patient had a pretreatment intracerebral hemorrhage and 47% were stuporous or comatose. AngioJet was the most commonly used device (40%). Intrasinus thrombolysis was used in 131 patients (71%). Overall, 156 (84%) patients had a good outcome and 22 (12%) died. Nine (5%) patients had no recanalization, 38 (21%) had partial, and 137 (74%) had near to complete recanalization. The major periprocedural complication was new or increased intracerebral hemorrhage (10%). The use of AngioJet was associated with lower rate of complete recanalization (odds ratio, 0.2; 95% confidence interval, 0.09–0.4) and lower chance of good outcome (odds ratio, 0.5; 95% confidence interval, 0.2–1.0). Conclusions— Our systematic review suggests that mechanical thrombectomy is reasonably safe but controlled studies are required to provide a definitive answer on its efficacy and safety in patients with cerebral venous thrombosis.

Isolated Cortical Vein Thrombosis: Systematic Review of Case Reports and Case Series

Background and Purpose— Isolated cortical vein thrombosis is a distinct subtype of cerebral venous and sinus thrombosis. Because of the rarity of isolated cortical vein thrombosis, limited knowledge on its clinical and radiological manifestations is available. Methods— We performed a systematic review of published data. Isolated cortical vein thrombosis had to have been diagnosed by MRI, conventional angiography, computed tomography venography, autopsy, or surgery. Cases with concurrent thrombosis of a cerebral sinus were excluded. Results— Of 175 potentially relevant studies, 47 were included in the analysis, with a total of 116 patients. All studies were case reports and case series. Mean age was 41 years and 68% were women. The most common symptoms were headache (71%), seizures (58%), and focal neurological deficits (62%). Papilledema was not reported in any patient, and increased cerebrospinal fluid pressure was reported only in 2. Infection (19%), pregnancy or puerperium (35% of women), and oral contraceptive use (21% of women) were the most common risk factors. Most cases (73%) were diagnosed with MRI, but conventional angiography was also performed in 47%. A total of 81% had a parenchymal brain lesion and 80% were treated with anticoagulation. In-hospital mortality was 6%. Conclusions— Signs of increased intracranial pressure seem to be less common in isolated cortical vein thrombosis compared with cerebral venous and sinus thrombosis. MRI and in some cases conventional angiography are the most frequently used diagnostic modalities and anticoagulation is the most widely used therapy.

Mechanical thrombectomy versus intrasinus thrombolysis for cerebral venous sinus thrombosis: a non-randomized comparison.

Small retrospective studies have shown the benefit of endovascular treatment with intrasinus thrombolysis (IST) or mechanical thrombectomy (MT) with/without IST (MT+/−IST) in cases of multifocal cerebral venous thrombosis (CVT). Our study compares the mortality, functional outcome and periprocedural complications among patients treated with MT +/– IST versus IST alone. We reviewed clinical and angiographic findings of 63 patients with CVT who received endovascular treatment at three tertiary care centers. Primary outcome variables were discharge mortality and neurological dysfunction, and intermediate (three months) and long-term (>six months) morbidity. The modified Rankin scale (mRS) was used to assess morbidity. mRS ≤1 was considered a good recovery. Neurological dysfunction was rated as neuroscore: 0, normal; 1, mild (ambulatory, communicative); 2, moderate (non-ambulatory, communicative); and 3, severe (non-ambulatory, non-communicative/comatose). In patients who received IST alone, presenting neurological deficits were comparatively minor (p<0.001). When the two groups were adjusted for admission neuroscore, there was no statistical significance between discharge mortality [7(21%) versus 4(14%), p=0.228], neurological dysfunction (p=0.442), intermediate (p=0.336) and long-term morbidity (p=0.988). Patients who received MT +/- IST had a higher percentage of periprocedural complications without reaching statistical significance. Compared to IST, MT was performed in severe cases with extensive sinus involvement. When adjusted for admission neurological dysfunction, both groups had similar mortality and discharge neurological dysfunction and similar intermediate and long-term morbidity.

Small juxtacortical hemorrhages in cerebral venous thrombosis

Intracerebral hemorrhages (ICHs) are common in patients with cerebral venous thrombosis (CVT). We examined whether small juxtacortical hemorrhages (JCHs) are characteristic for CVT and studied their radiological and pathological properties.

Admission Hyperglycemia and Clinical Outcome in Cerebral Venous Thrombosis

Background and Purpose— Admission hyperglycemia is associated with poor clinical outcome in ischemic and hemorrhagic stroke. Admission hyperglycemia has not been investigated in patients with cerebral venous thrombosis. Methods— Consecutive adult patients with cerebral venous thrombosis were included at the Academic Medical Center, The Netherlands (2000–2014) and the Helsinki University Central Hospital, Finland (1998–2014). We excluded patients with known diabetes mellitus and patients without known admission blood glucose. We defined admission hyperglycemia as blood glucose ≥7.8 mmol/L (141 mg/dL) and severe hyperglycemia as blood glucose ≥11.1 mmol/L (200 mg/dL). We used logistic regression analysis to determine if admission hyperglycemia was associated with modified Rankin Scale (mRS) score of 3 to 6 or mortality at last follow-up. We adjusted for: age, sex, coma, malignancy, infection, intracerebral hemorrhage, deep cerebral venous thrombosis, and location of recruitment. Results— Of 380 patients with cerebral venous thrombosis, 308 were eligible. Of these, 66 (21.4%) had admission hyperglycemia with 8 (2.6%) having severe admission hyperglycemia. Coma (31.3% versus 5.0%, P<0.001) and intracerebral hemorrhage (53.0% versus 32.6%, P=0.002) at presentation were more common among patients with admission hyperglycemia than normoglycemic patients. Patients with admission hyperglycemia had a higher risk of mRS score of 3 to 6 (adjusted odds ratio, 3.10; 95% confidence interval, 1.35–7.12) and mortality (adjusted odds ratio, 4.13; 95% confidence interval, 1.41–12.09). Severe hyperglycemia was even more strongly associated with mRS score of 3 to 6 (adjusted odds ratio, 11.59; 95% confidence interval, 1.74–77.30) and mortality (adjusted odds ratio, 33.36; 95% confidence interval, 3.87–287.28) compared with normoglycemic patients. Conclusions— Admission hyperglycemia is a strong predictor of poor clinical outcome in patients with cerebral venous thrombosis.

Association Between Anemia and Cerebral Venous Thrombosis Case–Control Study

Background and Purpose— Anemia is often considered to be a risk factor for cerebral venous thrombosis (CVT), but this assumption is mostly based on case reports. We investigated the association between anemia and CVT in a controlled study. Methods— Unmatched case–control study: cases were adult patients with CVT included in a single-center, prospective database between July 2006 and December 2014. Controls were subjects from the control population of the Multiple Environmental and Genetic Assessment of Risk Factors for Venous Thrombosis (MEGA) study. Anemia was defined according to World Health Organization criteria: nonpregnant women hemoglobin <7.5 mmol/L, pregnant women <6.9 mmol/L, and men <8.1 mmol/L. We used logistic regression analysis, adjusting for age, sex, malignancy, oral contraceptive use, and pregnancy/puerperium. Results— We included 152 cases and 2916 controls. Patients with CVT were younger (mean age, 40 versus 48 years) and more often women (74% versus 53%) than controls. Anemia was more frequent in cases (27.0%) than in controls (6.5%; P<0.001). Anemia was associated with CVT, both in univariate analysis (odds ratio, 5.3; 95% confidence interval [CI], 3.6–7.9) and after adjustment for potential confounders (adjusted odds ratio, 4.4; 95% CI, 2.8–6.9). Hemoglobin as a continuous variable was inversely associated with CVT (adjusted odds ratio per 1 mmol/L change 0.53; 95% CI, 0.42–0.66). Stratification by sex showed a stronger association between anemia and CVT in men (adjusted odds ratio, 9.9; 95% CI, 4.1–23.8) than in women (3.6; 95% CI, 2.1–6.0). Conclusion— Our data suggest that anemia is a risk factor for CVT.

Risk of Cerebral Venous Thrombosis in Obese Women

IMPORTANCE Obesity is a risk factor for deep vein thrombosis of the leg and pulmonary embolism. To date, however, whether obesity is associated with adult cerebral venous thrombosis (CVT) has not been assessed. OBJECTIVE To assess whether obesity is a risk factor for CVT. DESIGN, SETTING, AND PARTICIPANTS A case-control study was performed in consecutive adult patients with CVT admitted from July 1, 2006 (Amsterdam), and October 1, 2009 (Berne), through December 31, 2014, to the Academic Medical Center in Amsterdam, the Netherlands, or Inselspital University Hospital in Berne, Switzerland. The control group was composed of individuals from the control population of the Multiple Environmental and Genetic Assessment of Risk Factors for Venous Thrombosis study, which was a large Dutch case-control study performed from March 1, 1999, to September 31, 2004, and in which risk factors for deep vein thrombosis and pulmonary embolism were assessed. Data analysis was performed from January 2 to July 12, 2015. MAIN OUTCOMES AND MEASURES Obesity was determined by body mass index (BMI). A BMI of 30 or greater was considered to indicate obesity, and a BMI of 25 to 29.99 was considered to indicate overweight. A multiple imputation procedure was used for missing data. We adjusted for sex, age, history of cancer, ethnicity, smoking status, and oral contraceptive use. Individuals with normal weight (BMI <25) were the reference category. RESULTS The study included 186 cases and 6134 controls. Cases were younger (median age, 40 vs 48 years), more often female (133 [71.5%] vs 3220 [52.5%]), more often used oral contraceptives (97 [72.9%] vs 758 [23.5%] of women), and more frequently had a history of cancer (17 [9.1%] vs 235 [3.8%]) compared with controls. Obesity (BMI ≥30) was associated with an increased risk of CVT (adjusted odds ratio [OR], 2.63; 95% CI, 1.53-4.54). Stratification by sex revealed a strong association between CVT and obesity in women (adjusted OR, 3.50; 95% CI, 2.00-6.14) but not in men (adjusted OR, 1.16; 95% CI, 0.25-5.30). Further stratification revealed that, in women who used oral contraceptives, overweight and obesity were associated with an increased risk of CVT in a dose-dependent manner (BMI 25.0-29.9: adjusted OR, 11.87; 95% CI, 5.94-23.74; BMI ≥30: adjusted OR, 29.26; 95% CI, 13.47-63.60). No association was found in women who did not use oral contraceptives. CONCLUSIONS AND RELEVANCE Obesity is a strong risk factor for CVT in women who use oral contraceptives.