A new scientific statement from the American Heart Association (AHA) emphasises the need to boost patient and physician awareness of cerebral venous thrombosis (CVT), with a view to improving recognition of this condition and initiation of prompt medical treatment. The statement was published on 29 January in the AHA/American Stroke Association’s peer-reviewed journal Stroke.
This recent statement reviewed the latest evidence to update the AHA’s 2011 guideline outlining recommendations for diagnosing and managing CVT, focusing on advancements in treatment approaches including anticoagulation, catheter-based endovascular therapies, and surgery.
“Medical decisions undergo a thoughtful process, commencing with the suspicion of a diagnosis followed by the pursuit of relevant investigations to facilitate the implementation of optimal treatment. CVT serves as a relevant example in this regard,” Gustavo Saposnik (University of Toronto, Toronto, Canada), a leading author of the scientific statement, told NeuroNews. “Brain imaging, biomarkers, endovascular interventions and pharmacological therapies are rapidly advancing. It is anticipated that, in the next decade, we will witness a transformation in the approach to diagnosing and treating CVT.”
The statement initially details that CVT is a rare condition accounting for fewer than 3% of all strokes, and that it often affects younger patients; women who are pregnant, postpartum, or using oral contraceptives; and people with a tendency to form blood clots. It also notes that—in the years since the AHA’s 2011 statement—obesity and active COVID-19 infection have been identified as additional risk factors associated with CVT.
The statement goes on to report that the diagnosis of CVT is “challenging”, because the most common symptoms are persistent headaches and seizures, which may mimic other neurological conditions like migraines or epilepsy. Doctors typically use brain imaging, such as a magnetic resonance (MR) or computed tomography (CT) scan of the venous system, to identify CVT, but these tests “may not be routinely ordered” for patients presenting with headaches or seizures. As per the statement, recent evidence suggests that vascular imaging of the venous system using new MRI sequences or techniques could improve the likelihood of CVT diagnosis too.
The progression of CVT “may be difficult to predict”, according to the statement; while 80–90% of individuals with the condition achieve functional independence, many experience a variety of residual symptoms and—despite receiving intensive medical treatment—some 10–15% of patients experience severe outcomes, including death, disability, or loss of independence.
Standard treatment involves anticoagulation therapy to prevent growth of the blood clot causing CVT, and to ultimately facilitate reopening of the blood vessel and prevent recurrent clots. Recent studies, the statement continues, have shown that the use of direct oral anticoagulants (DOACs) appears to be a safe and effective alternative to vitamin K antagonists (VKAs) like warfarin.
However, according to the statement, “there is a need to identify other non-invasive treatments that are able to quickly dissolve blood clots and reduce pressure in the veins”. It goes on to detail that endovascular procedures are typically reserved for patients with neurological deterioration despite medical therapy, or for those who cannot take blood-thinning medications.
As per the statement, decompressive craniectomy involving surgical removal of a portion of the skull is a “life-saving procedure” to be considered for patients with severe CVT or progressive neurological deterioration. The statement adds that, “although there are no randomised controlled trials of this surgical approach, a meta-analysis of 51 studies found that surgery within 48 hours of admission may decrease mortality, and result in improved functional outcomes, in patients with severe or progressive disease”.
The analysis in question—published in the European Journal of Clinical Investigation in late 2022—included a total of 483 CVT cases treated via decompressive craniectomy, and also concluded that further prospective studies with appropriate control arms will be required to confirm the superior efficacy of surgery versus medical management.
Finally, the statement details that, in 2021, the US Centers for Disease Control and Prevention (CDC) and Food and Drug Administration (FDA) found that adenovirus-based SARS-CoV-2 vaccines were associated with vaccine-induced thrombotic thrombocytopaenia (VITT)—a condition that causes low blood platelet count and affects clotting. That said, CVT in VITT is “rare”, and there is “no evidence” of VITT in adults who received either of the two FDA-authorised mRNA COVID-19 vaccines from Pfizer and Moderna, the statement avers.
