Anticoagulant and antiplatelet therapy in patients with an unruptured intracranial aneurysm
- Alejandro A Rabinstein, MD
Alejandro A Rabinstein, MD
- Associate Professor of Neurology
- Mayo Clinic
- Section Editors
- Lawrence LK Leung, MD
Lawrence LK Leung, MD
- Editor-in-Chief — Hematology
- Section Editor — Disorders of Hemostasis and Coagulation
- Professor of Medicine
- Stanford University School of Medicine
- Jose Biller, MD, FACP, FAAN, FAHA
Jose Biller, MD, FACP, FAAN, FAHA
- Section Editor — Stroke
- Professor of Neurology and Neurological Surgery
- Chairman Department of Neurology
- Loyola University Chicago
- Stritch School of Medicine
Unruptured intracranial aneurysms are detected in up to 2 to 3 percent of older adults who undergo high-quality noninvasive intracranial arterial imaging (eg, magnetic resonance angiography, computed tomographic angiography). Subarachnoid hemorrhage from a ruptured intracranial aneurysm is associated with a short-term mortality of 40 percent, with one-half of survivors sustaining permanent neurologic injury. Thus, detection of an asymptomatic unruptured aneurysm creates a management dilemma in patients who have indications for antithrombotic therapy. (See "Unruptured intracranial aneurysms".)
This topic review will discuss issues related to anticoagulant and antiplatelet therapy in patients with an unruptured intracranial aneurysm.
RATE OF RUPTURE
Rates of rupture for previously detected unruptured aneurysms vary according to their size (ie, there is a greater risk of rupture in larger aneurysms), specific location (eg, higher rates of rupture with posterior circulation aneurysms) , as well as history of prior subarachnoid hemorrhage from a separate aneurysm . This subject is reviewed in depth separately, and will only be reviewed briefly here (see "Unruptured intracranial aneurysms", section on 'Risk of aneurysm rupture'):
●For patients with small (<7 mm) aneurysms in the anterior circulation and without a history of subarachnoid hemorrhage, the rupture rate is very low, below 0.1 percent per year.
●For similar patients who have moderate-sized aneurysms (7 to 12 mm), the rupture rate averages 2.5 percent per year.
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