Should a patient with a history of cerebrovascular accident (CVA) be on dual antiplatelet therapy (DAPT) if they were already on aspirin (acetylsalicylic acid)?

From the Guidelines

Dual antiplatelet therapy (DAPT) is not routinely recommended for patients with a history of cerebrovascular accident (CVA) who are already on aspirin. For most stroke patients, monotherapy with either aspirin (81-325 mg daily), clopidogrel (75 mg daily), or extended-release dipyridamole plus aspirin is the standard approach for secondary prevention, as stated in the 2021 guideline for the prevention of stroke in patients with stroke and transient ischemic attack 1. DAPT with aspirin plus clopidogrel may be considered in specific situations, such as in the acute phase (first 21 days) following a minor ischemic stroke or high-risk TIA, or for patients with recent stenting. However, long-term DAPT increases bleeding risk without providing additional benefit for most stroke patients, as there is limited evidence to support the benefit of changing antiplatelet medications in patients already taking one medication at the time of stroke 1.

Some key points to consider when deciding on DAPT for patients with CVA include:

• The risk of bleeding complications, such as hemorrhagic transformation of the ischemic stroke or other bleeding complications, especially in patients with large stroke or microhemorrhages 1
• The optimal combination of medications, timing of initiation, and duration of DAPT, which remains uncertain and requires further research 1
• The effectiveness and potential harm of DAPT among specific subgroups of patients according to stroke characteristics, laboratory or genetic tests, or other factors, which is not well established 1
• The potential benefits of switching antiplatelet agents for patients already taking one antiplatelet medication at the time of stroke, which is not supported by strong evidence 1

In general, the decision to use DAPT in patients with CVA should be individualized based on the patient's stroke etiology, bleeding risk, and other comorbidities, and should take into account the latest guidelines and evidence, such as the 2021 guideline for the prevention of stroke in patients with stroke and transient ischemic attack 1 and the 2024 ESC guidelines for the management of chronic coronary syndromes 1. Patients with cardioembolic strokes due to atrial fibrillation generally require anticoagulation rather than antiplatelet therapy.

From the FDA Drug Label

Prasugrel tablets are contraindicated in patients with a history of prior transient ischemic attack (TIA) or stroke In TRITON-TIMI 38 (TRial to Assess Improvement in Therapeutic Outcomes by Optimizing Platelet InhibitioN with Prasugrel), patients with a history of TIA or ischemic stroke (>3 months prior to enrollment) had a higher rate of stroke on prasugrel tablets

The patient should not be on DAPT with prasugrel after a CVA if they were already on aspirin, due to the increased risk of bleeding and stroke associated with prasugrel in patients with a history of TIA or stroke 2.

From the Research

Dual Antiplatelet Therapy (DAPT) After CVA

• The decision to use DAPT in patients with a history of cerebrovascular accident (CVA) who are already on aspirin should be made on an individual basis, considering the risk of bleeding and the potential benefits of preventing further ischemic events 3, 4.
• Studies have shown that DAPT with aspirin and a P2Y12 inhibitor (such as clopidogrel, prasugrel, or ticagrelor) can be effective in preventing recurrent strokes after minor ischemic stroke or transient ischemic attack (TIA) 4.
• However, the use of DAPT in patients with a history of CVA also increases the risk of bleeding, particularly in patients with a history of intracranial hemorrhage 3, 5.
• The choice of P2Y12 inhibitor to use in combination with aspirin should be made based on the individual patient's risk factors and medical history, as well as the potential side effects of each medication 5.

Considerations for DAPT Use

• Patients with a history of CVA who are already on aspirin may benefit from the addition of a P2Y12 inhibitor to their treatment regimen, particularly if they have a high risk of recurrent ischemic events 4, 6.
• However, the risks and benefits of DAPT should be carefully weighed, particularly in patients with a history of bleeding or those who are at high risk of bleeding 3, 7.
• The duration of DAPT therapy should also be considered, as longer durations of therapy may increase the risk of bleeding while providing ongoing protection against ischemic events 6.

Evidence for DAPT Use

• Studies have shown that DAPT with aspirin and a P2Y12 inhibitor can be effective in preventing recurrent strokes after minor ischemic stroke or TIA, with a number needed to treat (NNT) of 42 to prevent one recurrent stroke or death 4.
• However, the evidence for the use of DAPT in patients with a history of CVA is limited, and further studies are needed to fully understand the risks and benefits of this treatment strategy 3, 7.