Purpose: To assess the long-term safety and efficacy of the intravascular lithotripsy system for pre-treatment of calcified carotid artery stenosis.

Design: Prospective, multicenter, single-arm study with an extended follow-up period.

Sample Size: 204 participants (based on the final number of cases enrolled in the registration trial).

Endpoints:

Primary: Surgical success rate (residual stenosis <30% after stenting). Secondary: Target lesion re-narrowing rate, target lesion revascularization rate, MAE rate, ipsilateral stroke rate, and MACCE rate at 3 and 6 months postoperatively.

Follow-Up: Participants will be followed up at 3 months ±15 days and 6 months ±30 days postoperatively.

Inclusion criteria:

All patients participating in this extended follow-up period are sourced from the registered clinical trial.

Ethics and Consent: The trial will be conducted in accordance with the Helsinki Declaration and Chinese regulations. Informed consent will be obtained from all participants or their legal guardians.

Sponsor: Shanghai Lanfan Boyuan Medical Technology Co., Ltd. Principal Investigator: Professor Huo Xiaochuan, Beijing Anzhen Hospital.

### Detailed Description

This clinical trial evaluates the safety and long-term efficacy of a disposable neurovascular intravascular lithotripsy (IVL) catheter and intravascular lithotripsy treatment device for pre-treatment of calcified lesions in the extracranial segment of the carotid artery. The study is designed as a prospective, multicenter, single-arm trial （extended follow-up period）.

#### Study Population:

All patients participating in this extended follow-up period are sourced from the registered clinical trial.（The registered clinical trial:Participants aged 18-80 years with symptomatic (≥50%) or asymptomatic (≥70%) calcified carotid artery stenosis confirmed by CT angiography (CTA) and digital subtraction angiography (DSA) are eligible. Patients who have failed conventional balloon dilation and are planned for carotid artery stenting (CAS) will be included.）

#### Follow-Up: Participants will be followed up at 3 months ±15 days and 6 months ±30 days postoperatively. Assessments will include clinical evaluations, imaging studies (CT angiography or carotid ultrasound), and recording of adverse events.

• Endpoints:

  • **Primary Endpoint**: Surgical success rate defined as residual stenosis <30% after stenting.
  • **Secondary Endpoints**: Target lesion re-narrowing rate, target lesion revascularization rate, MAE (major adverse events) rate, ipsilateral stroke rate, and MACCE (major adverse cardiovascular and cerebrovascular events) rate at 3 and 6 months postoperatively.

• Ethical Considerations:

Informed consent will be obtained from all participants or their legal guardians. The study will be conducted in accordance with the Helsinki Declaration and local regulatory requirements.

Inclusion criteria:

All patients participating in this extended follow-up period are sourced from the registered clinical trial.

Exclusion criteria:

none

All patients participating in this extended follow-up period are sourced from the registered clinical trial.