We thank Coutinho and colleagues for their comments on our manuscript. They state that the 4% mortality associated with noninvasive anticoagulant treatment in the International Study on Cerebral Vein and Dural Sinus Thrombosis (ISCVT) is superior to our observed mortality rate of 15% (2 of 13 patients). The ISCVT is a large prospective trial, which is detailed in the Discussion of our article. A direct comparison of mortality rates between ISCVT and our small case series is not meaningful. In our series the 15% mortality rate was related to the damage that was already done by venous sinus thrombosis. These patients were already neurologically devastated before our intervention—their deaths were not a result of the procedure. It is even possible that outcomes would have been better had we intervened in those patients sooner. We have been involved in several cases where patients were managed with anticoagulation initially for some time but continued to worsen. By the time mechanical thrombectomy was brought to the table, they were already devastated. Coutinho and colleagues state that in the absence of additional risk factors for a poor prognosis, they would not treat any patients with endovascular therapy. However, they do not consider the problems associated with long-term refractory headaches often experienced by sinus thrombosis patients. In our series all 6 patients who presented primarily with severe headaches experienced complete and immediate resolution of their headaches after mechanical thrombectomy. Coutinho et al. also point out that there was no control group in our series and that follow up was incomplete. These issues of course reflect the retrospective nature of this case series; it was not a randomized controlled trial. The key point of our report is that endovascular therapy for venous sinus thrombosis can be performed with minimal risk in experienced hands. Mechanical intervention markedly reduces the volume of thrombus and quickly restores flow. Once flow is established, the residual thrombus responds more completely and more quickly to systemic anticoagulation. We believe this approach greatly reduces the duration and severity of symptoms and can shorten hospital stays and the required convalescence period.

Shervin R. Dashti, M.D. Louisville, Kentucky Cameron G. McDougall, M.D. Phoenix, Arizona

Conflict of Interest:

None declared

To the Editor:

The paper by Dashti et al. (1) describes 13 patients who received mechanical thrombectomy with the AngioJet device as first line treatment for cerebral venous thrombosis (CVT). Mechanical thrombectomy is a promising alternative to endovascular thrombolysis with thrombolytic drugs. Hemorrhagic infarcts are common among CVT patients and it is plausible - although unproven - that mechanical thrombectomy gives less hemorrhagic complications.

There are however some issues that render the authors' suggestion to use mechanical thrombectomy as a first line treatment for CVT untenable. First, the paper gives insufficient information about the baseline condition of the patients, especially the presence of intracranial hemorrhages before the procedure. The Glasgow Coma Scale was optimal in 7 patients. In the absence of additional risk factors for a poor prognosis - not mentioned by the authors - we would not treat these patients with endovascular therapy. Second, follow-up is incomplete, and there is no control group in the study. Without a control group it is impossible to conclude that endovascular treatment is better than standard treatment. The prognosis of CVT after heparin treatment is usually good. In the 'International study on cerebral vein and dural sinus thrombosis' (ISCVT), a prospective study of 624 patients, mortality at discharge was 4% with non-invasive anticoagulant treatment (2). This is better than the 15% peri -operative mortality (2 out of 13) reported by Dashti et al.

We therefore disagree with the suggestion that mechanical thrombectomy should be considered as first line treatment for CVT. In patients without risk factors for a poor prognosis, anticoagulant treatment according to international guidelines (3,4) is usually effective. Patients with one or more risk factors may benefit from endovascular treatment, but there are no appropriately controlled studies. Therefore, we recently launched the TO-ACT study (Thrombolysis Or Anticoagulation for Cerebral venous Thrombosis), an international randomized trial (www.clinicaltrials.gov; NCT01204333). Patients are eligible if they have severe CVT, as defined by the risk factors: intracranial hemorrhage, coma, mental status disorder or thrombosis of the deep venous system. The type of endovascular treatment is to be decided by the local investigator and may be pharmacological, mechanical, or a combination. A sensitivity analysis of the type of endovascular thrombolysis is planned. More information about the trial is available at www.to-act-trial.org.

JM Coutinho, R van den Berg, SM Zuurbier, CB Majoie and J Stam

Academic Medical Center, Amsterdam, the Netherlands j.coutinho@amc.uva.nl

References 1. Dashti SR, Hu YC, Yao T, Fiorella D, Mitha AP, Albuquerque FC, McDougall CG. Mechanical thrombectomy as first-line treatment for venous sinus thrombosis: technical considerations and preliminary results using the AngioJet device. J Neurointerv Surg. 2011 Dec 5. [Epub ahead of print]

2. Ferro JM, Canhao P, Stam J, Bousser MG, Barinagarrementeria F. Prognosis of cerebral vein and dural sinus thrombosis: results of the International Study on Cerebral Vein and Dural Sinus Thrombosis (ISCVT). Stroke. 2004;35:664-70.

3. Einhaupl K, Stam J, Bousser MG, De Bruijn SF, Ferro JM, Martinelli I, Masuhr F; European Federation of Neurological Societies. EFNS guideline on the treatment of cerebral venous and sinus thrombosis in adult patients. Eur J Neurol. 2010 Oct;17(10):1229-35.

4. Saposnik G, Barinagarrementeria F, Brown RD Jr, Bushnell CD, Cucchiara B, Cushman M, deVeber G, Ferro JM, Tsai FY; American Heart Association Stroke Council and the Council on Epidemiology and Prevention. Diagnosis and management of cerebral venous thrombosis: a statement for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2011 Apr;42(4):1158-92

Conflict of Interest:

None declared