What are the secondary prevention strategies for basilar artery occlusion (BAO) related stroke?

From the Guidelines

For secondary stroke prevention after basilar artery occlusion, a combination of antiplatelet therapy, risk factor modification, and adherence to medication regimens is crucial to prevent devastating outcomes. The most recent guideline from the American Heart Association/American Stroke Association [ 1 ] emphasizes the importance of adhering to pharmacological secondary prevention strategies, with multimodal interventions and self-management interventions showing a moderate effect size in adherence to prescribed secondary prevention medications.

Key Components of Secondary Prevention

• Antiplatelet therapy: dual antiplatelet therapy with aspirin 81-325 mg daily plus clopidogrel 75 mg daily is typically prescribed for 21-90 days, followed by lifelong single antiplatelet therapy (usually aspirin 81 mg daily or clopidogrel 75 mg daily) [ 1 ].
• Risk factor modification: lifestyle modifications including smoking cessation, limited alcohol intake, regular physical activity, and a Mediterranean or DASH diet are essential components of prevention [ 1 ].
• Anticoagulation: if the stroke was caused by atrial fibrillation or another cardioembolic source, anticoagulation with a direct oral anticoagulant (DOAC) such as apixaban 5 mg twice daily, rivaroxaban 20 mg daily, dabigatran 150 mg twice daily, or edoxaban 60 mg daily is preferred over antiplatelet therapy.
• Statin therapy: for patients with significant basilar atherosclerosis (>50% stenosis), high-intensity statin therapy with atorvastatin 40-80 mg or rosuvastatin 20-40 mg daily is crucial to achieve LDL levels below 70 mg/dL.
• Blood pressure control: blood pressure should be controlled to less than 130/80 mmHg using appropriate antihypertensives.

Improving Adherence to Medication Regimens

• Multimodal interventions: have been shown to improve compliance with antithrombotic medications and statins [ 1 ].
• Self-management interventions: have similarly shown a moderate effect size in adherence to prescribed secondary prevention medications [ 1 ].
• Assistive technology: may play an emerging role in improving adherence, with the SMS4Stroke trial showing an adjusted mean difference of 0.54 in the Morisky Medication Adherence Scale score after 2 months of receiving short messaging service reminders [ 1 ].

From the Research

Basilar Occlusion Secondary Stroke Prevention

• The management of posterior circulation stroke, including basilar occlusion, has received less attention than similar interventions for the anterior circulation 2.
• Secondary prevention of posterior circulation strokes includes aggressive treatment of cerebrovascular risk factors with both drugs and lifestyle interventions and short-term dual anti-platelet therapy 2.
• Randomized controlled trial (RCT) data suggest basilar artery stenosis is better treated with medical therapy than stenting, which has a high peri-procedural risk 2.
• Antiplatelet therapy remains the standard of care in secondary stroke prevention for non-cardioembolic ischemic stroke and transient ischemic attack, with options including aspirin, clopidogrel, and dipyridamole 3, 4.
• Recent developments for secondary stroke prevention include evidence to support the use of short-term dual antiplatelet therapy after minor stroke and transient ischemic attack 5, 4.

Medical Management

• The mainstays of medical management for secondary stroke prevention include antihypertensive therapy, antithrombotic therapy, cholesterol-lowering therapy, and glycemic control 5.
• Antithrombotic therapy, with antiplatelet agents for most stroke subtypes or anticoagulants such as warfarin or a direct oral anticoagulant for cardioembolic stroke specifically, is a key component of secondary stroke prevention 5.
• Combination antiplatelet therapy with aspirin and the P2Y12 inhibitors, clopidogrel and ticagrelor, reduced stroke recurrence in those presenting with mild ischemic stroke or high risk TIA 4.

Treatment of Posterior Circulation Stroke

• Acute revascularization of posterior circulation strokes remains largely unproven, but thrombolysis seems to have similar benefits and lower hemorrhage risks than in the anterior circulation 2.
• The recent ATTENTION and BAOCHE trials have demonstrated that thrombectomy benefits strokes with basilar artery occlusion, but its effect on other posterior occlusion sites remains uncertain 2.
• Ischemic and hemorrhagic space-occupying cerebellar strokes can benefit from decompressive craniectomy 2.