Is a stroke occurring 12 hours after carotid artery reperfusion a potential complication of the procedure, despite dual anti-platelet therapy (aspirin and P2Y12 inhibitor, such as clopidogrel) being stopped prior to surgery?

Stroke 12 Hours Post-Carotid Reperfusion: Likely a Procedural Complication

Yes, a stroke occurring 12 hours after carotid artery reperfusion is most likely a manifestation of the procedure itself, and the prior discontinuation of dual antiplatelet therapy (DAPT) significantly increases this thrombotic risk.

Understanding the Mechanism

The stroke you describe is occurring in the immediate post-procedural period and represents one of two primary complications of carotid revascularization:

Thrombotic Stroke (Most Likely)

• Perioperative thromboembolism is the leading cause of stroke within the first 24-48 hours after carotid endarterectomy (CEA) or carotid artery stenting (CAS) 1
• The discontinuation of DAPT prior to surgery creates a prothrombotic window where platelet aggregation and thrombus formation at the surgical site or stent can occur 2
• Post-operative embolization from the revascularized carotid is a well-documented phenomenon that can be detected by transcranial Doppler monitoring 2

Hyperperfusion Syndrome (Less Common but Possible)

• Cerebral hyperperfusion syndrome (CHS) can occur after carotid revascularization when chronically hypoperfused brain tissue suddenly receives increased blood flow 3
• CHS typically presents with headache, hypertension, seizures, and can lead to intracerebral hemorrhage 3
• This complication usually manifests within 12 hours to several days post-procedure and is preceded by uncontrolled blood pressure elevation 1

The Critical Role of Antiplatelet Therapy

Why DAPT Discontinuation Increases Risk

The decision to stop DAPT before carotid surgery creates a significant thrombotic vulnerability:

• Clopidogrel requires 5 days of discontinuation before surgery to allow 50-70% platelet function recovery 4
• During this washout period and immediately post-operatively, patients are at heightened risk for thrombotic complications 5
• Recent evidence demonstrates that continuing DAPT through CEA does not increase bleeding complications but significantly reduces post-operative embolization and thrombotic stroke 6

Current Best Practice for Antiplatelet Management

For CEA patients, the optimal approach is:

• Single antiplatelet therapy (aspirin 75-325 mg daily) should be continued perioperatively 1
• Early implementation of DAPT (in the TIA clinic after excluding hemorrhage) is associated with a five-fold reduction in recurrent neurological events prior to expedited CEA 1
• Clopidogrel or low-dose aspirin should be administered on day 1 post-CEA and continued for 1-3 months 1, 7

For CAS patients:

• DAPT with aspirin (81-325 mg) plus clopidogrel (75 mg) should be given before and for minimum 30 days after stenting 7
• DAPT is typically continued for 4-6 weeks with single-layer stents, then transitioned to single antiplatelet therapy 1

Clinical Assessment and Management

Immediate Evaluation Required

Determine the stroke mechanism through:

• Urgent brain imaging (CT or MRI) to differentiate ischemic stroke from hemorrhagic transformation or hyperperfusion syndrome 3
• Blood pressure assessment—uncontrolled hypertension suggests hyperperfusion syndrome 1
• Vascular imaging to evaluate for acute thrombosis at the surgical/stent site
• Consider transcranial near-infrared spectroscopy or SPECT to evaluate cerebral blood flow if hyperperfusion is suspected 3

Management Based on Mechanism

If thrombotic stroke:

• Resume antiplatelet therapy immediately if not contraindicated by hemorrhage 5, 4
• Consider loading doses: clopidogrel 300-600 mg and aspirin 160 mg 7
• Evaluate for urgent re-intervention if acute thrombosis is identified

If hyperperfusion syndrome:

• Strict blood pressure control is paramount—maintain systolic BP <140-160 mmHg 1
• Avoid aggressive antiplatelet therapy if hemorrhagic transformation has occurred
• Monitor closely for seizures and increased intracranial pressure 3

Key Pitfalls to Avoid

Common errors in perioperative antiplatelet management:

• Stopping aspirin unnecessarily before CEA—aspirin should be continued perioperatively 1
• Delaying resumption of antiplatelet therapy post-operatively—restart within 24 hours when hemostasis is achieved 5, 4
• Failing to recognize that the thrombotic risk from stopping antiplatelet therapy often exceeds the bleeding risk from continuing it 4
• Not maintaining strict blood pressure control in the first 24-48 hours post-procedure 1

Evidence-Based Outcomes

Recent data demonstrates:

• 30-day stroke and death rates after CEA have declined to 2.7% in symptomatic patients and 1.5% in asymptomatic patients 1
• Dual antiplatelet therapy administered preoperatively (single 75 mg clopidogrel dose the night before plus daily aspirin) reduces post-operative embolization from 3.2% to 0.4% 2
• No increase in major bleeding complications occurs with this approach 2, 6

The stroke at 12 hours post-reperfusion represents a recognized complication of carotid revascularization, with the prior DAPT discontinuation likely contributing to increased thrombotic risk rather than protecting against it.