What is the recommended follow-up for a patient with a history of right carotid stenting, with the last procedure performed in 2021, including the need for carotid ultrasound and antiplatelet therapy with aspirin (acetylsalicylic acid) and clopidogrel?

Follow-up Protocol for Patients with Carotid Artery Stents

Recommended Surveillance Schedule

After carotid artery stenting, duplex ultrasound surveillance is recommended within the first month, followed by regular monitoring at 6-12 months, and then annually if findings remain stable. 1, 2

The follow-up protocol for a patient who underwent right carotid stenting in 2021 should include:

Imaging Surveillance

• Initial duplex ultrasound should have been performed within 1 month post-procedure to establish baseline status
• Current recommendation (for a patient with stenting in 2021):
  • Perform duplex ultrasound now if not done within the past 12 months
  • Continue with annual ultrasound surveillance if previous studies showed no significant restenosis
  • Increase frequency to every 6 months if any degree of restenosis (>50%) is detected

Duplex Ultrasound Parameters

• Specialized velocity criteria for stented carotids should be used:
  • Significant restenosis: Peak-systolic velocity ≥3 m/s and end-diastolic velocity ≥1.4 m/s 2
  • Standard velocity criteria used for native carotids may overestimate stenosis in stented vessels

Antiplatelet Therapy Management

Current Recommendations

• After initial carotid stent placement, dual antiplatelet therapy (DAPT) with aspirin and clopidogrel is recommended for at least 1 month 1
• For long-term management (applicable to this patient who had stenting in 2021):
  • Single antiplatelet therapy with either aspirin or clopidogrel should be continued indefinitely 1
  • The choice between aspirin or clopidogrel should be based on patient tolerance and comorbidities

Dosing

• If using aspirin: 81-325 mg daily 3, 4
• If using clopidogrel: 75 mg daily 3

Additional Medical Management

• Intensive lipid-lowering therapy aiming at >50% LDL-C reduction and LDL-C <1.4 mmol/L (55 mg/dL) 1
• Proper blood pressure control to optimize outcomes and reduce risk of stroke 1
• Annual assessment of cardiovascular risk factors and medication adherence 1
• Formal neurologic examination to assess long-term efficacy of carotid revascularization 1, 2

Restenosis Management

If significant restenosis (>70%) is detected:

• In symptomatic patients with recurrent stenosis due to intimal hyperplasia or atherosclerosis, repeat revascularization (CAS or CEA) is reasonable using the same criteria as for initial revascularization 1
• In asymptomatic patients with recurrent stenosis >70%, consider repeat intervention if the stenosis has progressed rapidly or threatens complete occlusion 1
• Reoperative CEA or CAS should not be performed in asymptomatic patients with <70% carotid stenosis that has remained stable over time 1

Common Pitfalls and Considerations

1. Overestimation of stenosis: Standard velocity criteria used for native carotids may overestimate stenosis in stented vessels; specialized criteria should be used 2

2. Premature discontinuation of surveillance: Even with stable findings, long-term surveillance is important as late restenosis can occur years after the procedure 1

3. Inappropriate antiplatelet management: Premature discontinuation of antiplatelet therapy increases risk of thrombotic events; however, prolonged DAPT beyond recommended duration increases bleeding risk without clear benefit 1, 3

4. Neglecting overall cardiovascular risk: Focus should not be solely on the carotid artery but should include comprehensive management of all cardiovascular risk factors 1

5. Unnecessary intervention for asymptomatic restenosis: Not all restenoses require intervention, particularly in asymptomatic patients with stable, moderate stenosis 1

By following this structured approach to surveillance and management, the risk of recurrent stroke and other adverse events can be minimized in patients with carotid artery stents.