Restarting Antithrombotic Therapy After Intracerebral Hemorrhage

Patients with intracerebral hemorrhage often have concurrent ischemic vascular disease, venous thromboembolic disease, or atrial fibrillation for which antiplatelet (AP) or anticoagulant (AC) therapy would be indicated. Deciding if and when to start or restart antithrombotic therapy in these patients is a common challenge in clinical care. Determining the underlying cause of the intracerebral hemorrhage helps predict the risk of recurrent bleeding. Similarly, the risk of thromboembolism should be estimated based on the specific clinical scenario. This then allows one to weigh the risks and benefits of therapy. In general, those with a prior vascular event (secondary prevention) are at higher risk than those who are clinically asymptomatic (primary prevention), and those with a recent event more at risk than those with a remote event. Risk scores such as the CHA2DS2-VASc score can help stratify thrombotic risk in patients with atrial fibrillation; patients with mechanical heart valves are at high risk even without a history of prior ischemic events.

A.

Hypertensive hemorrhage typically affects the deep, subcortical structures. The risk of recurrence is about 2% per year; this can be significantly reduced with aggressive blood pressure control. Even so, the risk of recurrent hemorrhage often exceeds the risk of a future ischemic event in low-risk patients, such that antithrombotic agents are likely to cause more harm than benefit.
B.

Amyloid angiopathy is a common cause of lobar or multicompartment hemorrhage in elderly patients. The risk of recurrent bleeding in patients with amyloid angiopathy is very high even in the absence of antithrombotic agents (~ 10% per year), and therefore it is generally recommended to avoid all antiplatelet and anticoagulant agents regardless of indication.
C.

Coagulopathic hemorrhages can occur in the setting of therapeutic or supratherapeutic anticoagulation, or when anticoagulation is combined with an antiplatelet agent. In general, if the hemorrhage occurred while on warfarin or in the setting of combination therapy with an anticoagulant and antiplatelet, transition to direct oral anticoagulant (DOAC) monotherapy should be considered given the lower risk of intracranial hemorrhage with these agents compared to warfarin. When intracerebral hemorrhage occurs in the context of DOAC use, the cause of hemorrhage and the indication for therapy should guide decision-making.
D.

Hemorrhagic transformation of an ischemic stroke is quite different from a primary intracerebral hemorrhage in that the underlying precipitating event is ischemia. Accordingly, the long-term risk of recurrent hemorrhage is low, and the risk of recurrent ischemia may be relatively high. Hemorrhagic conversion can be characterized on imaging as petechial hemorrhage , in which case antithrombotic therapy can usually be continued without cessation, or parenchymal hematoma , in which case antithrombotic therapy is typically held for at least 1 week and possibly as long as 4 weeks depending on the size of the infarction and the hemorrhage, and the short-term risk of recurrent ischemia (determined by stroke mechanism).
E.

Cavernous malformations, or cavernomas, can be identified incidentally or in the context of acute hemorrhage. If identified incidentally, without prior clinical symptoms of hemorrhage, it is reasonable to start or continue antiplatelet agents or anticoagulation in most patients based on vascular indication; the exception is low-risk primary prevention in which the risk-benefit ratio is quite unclear. In the setting of prior clinical hemorrhage, antithrombotic therapy is reasonable for patients at high risk of recurrent vascular events. However, brainstem cavernomas often have higher risk of bleeding and the consequence of recurrent hemorrhage is more significant, so a patient-centered discussion of the risks versus benefits of therapy is warranted.
F.

Once secured by either surgical or endovascular intervention, arteriovenous malformations (AVMs) and cerebral aneurysms have a low risk of recurrent hemorrhage and antiplatelet or anticoagulant therapy can be used as needed.