Optimum antithrombotic therapy for primary and secondary prevention of ischemic stroke- Salient features

Stroke is a medical emergency with significant mortality and morbidity worldwide. Antithrombotic therapy plays an important role in both primary and secondary prevention of stroke events, In cases of small-vessel disease and large-artery atherosclerosis, single or dual antiplatelet therapy is generally preferred, whereas in conditions of blood stasis or hypercoagulable states that mostly result in red thrombi, anticoagulation is recommended. However, there is a need to weigh the benefit of antithrombotic therapies against the increased bleeding risk that can pose significant challenges in the pharmacological management of this condition.

The following are key points from the review on antithrombotic therapy for primary and secondary prevention of ischemic stroke:

• Decisions regarding antithrombotic treatment in primary and secondary stroke prevention should always involve consideration of the individual patient’s bleeding risk.
• Dual antiplatelet therapy (DAPT) with clopidogrel and aspirin or ticagrelor and aspirin is indicated for a short time (~21 days) after minor acute ischemic stroke or transient ischemic attack. Antiplatelet monotherapy should be initiated after the short course of DAPT is completed.
• The default treatment for secondary stroke prevention should be an antiplatelet agent (e.g., aspirin or clopidogrel monotherapy), generally initiated within 24-48 hours after symptom onset.
• Decisions regarding the timing of initiation or reinitiation of anticoagulation for AF after ischemic stroke should be informed by infarct size, evidence of hemorrhagic transformation, and patient-specific factors (e.g., presence of comorbid deep vein thrombosis).
• Ischemic stroke patients with nonvalvular atrial fibrillation (AF) and no contraindication should receive anticoagulation with a DOAC or warfarin.
• The treatment of choice for secondary stroke prevention after ESUS (embolic stroke of undetermined source) is antiplatelet monotherapy.
• Anticoagulation with warfarin is the treatment of choice for left ventricular thrombus to prevent stroke and/or systemic embolism.
• Anticoagulation is generally the antithrombotic treatment of choice for antiphospholipid antibody syndrome and recurrent ischemic stroke felt secondary to malignancy-related hypercoagulability.
• Either aspirin or warfarin may be used in the first 3 months after a vertebral or carotid artery dissection.

The review stated, "There is a need for more research to define optimum antithrombotic regimens for patients with embolic stroke of undetermined source, arterial dissection, and specific forms of nonatherosclerotic vascular disease."

Reference:

Antithrombotic Therapy for Primary and Secondary Prevention of Ischemic Stroke: JACC State-of-the-Art Review. J Am Coll Cardiol 2023;82:1538-1557.