Cardiovascular diseases are usually complex and affect several organs at the same time. Therefore, the treatment of vascular diseases in the brain may have implications for the treatment of heart disease. It is therefore important to understand the appropriate causes and consequences.
This study investigates the causes of intracerebral hemorrhage and links them to the risk of stroke associated with atrial fibrillation. He suggests a new thorough assessment of the effects of blood thinning on intracerebral hemorrhage.
Every year in Switzerland, about 1,000 patients with intracerebral hemorrhage are treated at stroke units. Intracerebral hemorrhages are more often fatal than other forms of stroke, and their incidence has not decreased in the last 30 years. It was previously thought that the use of blood thinners is not only a risk factor but also a potential cause of intracerebral hemorrhage.
Anticoagulation should not be considered the primary cause
This publication includes the results of two studies conducted by a team of prof. Werringa. It opposes the role of blood thinning to the role of cerebrovascular disease (SVD) in intracerebral hemorrhage. Moderate to severe cerebral SVD has been shown to be closely associated with the occurrence of cerebral hemorrhage.
Our results show that SVD is a prerequisite for intracerebral hemorrhage under anticoagulation. The degree of SVD in the brain can be used to predict intracerebral hemorrhage. Without SVD, the occurrence of intracerebral hemorrhage is close to zero. Therefore, anticoagulation should no longer be considered a cause of intracerebral hemorrhage. “
Dr. David Seiffge, Inselspital, University Hospital Bern
Why is this important? Stroke protection in patients with atrial fibrillation
Blood thinning offers important protection against ischemic stroke in patients with atrial fibrillation. Anticoagulation reduces the risk of ischemic stroke in these cases by two-thirds. In the past, anticoagulation was stopped immediately in case of intracerebral hemorrhage, and patients remained unprotected from the risk of stroke.
The results of the new study now point to a new path: according to the findings, intracerebral hemorrhage can be etiologically prevented by treating cerebral SVD, and stroke protection can be maintained through a customized continuation of blood thinning. The exact timing and gradation of the two therapies are the subject of further studies.
Challenging methodological approach: combining two multicenter studies
The publication contains data from two independent studies under the supervision of prof. David Werring, UCL. The publication is based on two independent, multicenter observational studies. A cross-sectional study was conducted with 1,030 patients with intracerebral hemorrhage. CT and MRI were used to look for markers of SVD in the brain.
In another, prospective study, 1,447 patients with atrial fibrillation and cerebral circulation disorders were included. The incidence of cerebral hemorrhage and ischemic stroke in relation to blood thinning was considered in this group.
Using this approach, it was possible to show that SVD is a prerequisite for intracerebral hemorrhage. Patients without such a condition did not have any cerebral hemorrhage in the first two years of the study, despite treatment with blood thinner. In contrast, at 1.56% per year, the risk was significantly increased for moderate to severe SVD.
A new way of looking at the situation is needed
The results of the study suggest that blood thinning alone can no longer be considered a cause of intracerebral hemorrhage. Professor Marcel Arnold points out: “As a new approach, microangiopathies need to be systematically sought and targeted to prevent intracerebral hemorrhages. Appropriate specialist clinics are now available. This would reduce the risk of intracerebral hemorrhage. »
A large international randomized trial (ENRICH-AF), currently coordinated in Switzerland by David Seiffge, is currently underway to harmonize anticoagulation and microangiopathy therapies.
Inselspital, University Hospital of Bern
Seiffge, DJ, and others. (2021) The burden of small vessel disease and intracerebral hemorrhage in patients taking oral anticoagulants. Journal of Neurology, Neurosurgery and Psychiatry. doi.org/10.1136/jnnp-2020-325299.