This prospective, multi-center clinical trial evaluates the safety and efficacy of the Coronary Laser Atherectomy System for the pretreatment of coronary artery stenosis. The study consists of two phases: a first-in-human (FIM) phase enrolling 5 subjects in a single center, and a pivotal phase, which is a prospective, multi-center, randomized controlled, non-inferiority trial enrolling 218 subjects across approximately 10 centers in China. Subjects are randomized 1:1 to receive either the investigational laser system or the control Philips CVX300 laser system for lesion pretreatment prior to PCI. The primary endpoint is clinical success, defined as successful PCI with residual stenosis <30%, TIMI flow grade 3, and no death, myocardial infarction, or target lesion revascularization through 7 days post-procedure. Secondary endpoints include device success, procedural success, MACE, target lesion failure, and target vessel failure at 30 days and 6 months. An OCT sub-study is planned for 40 subjects.

Inclusion Criteria:

Clinical Inclusion Criteria:

1. Age 18-85 years, male or female.
2. Coronary angiography confirms the need for PCI.
3. Diagnosed with stable angina, silent myocardial ischemia, unstable angina, non-ST-segment elevation myocardial infarction, or STEMI >7 days.
4. During PCI, the investigator determines that laser atherectomy is required for lesion pretreatment.
5. Able to understand the purpose of the trial, voluntarily participate and sign the informed consent form acknowledging the risks and benefits described in the informed consent document, and able to complete clinical follow-up as required.

Angiographic Inclusion Criteria (visual estimate):

1. Target lesion reference vessel diameter (RVD) ≥2.00 mm by visual estimate.

2. Target lesion stenosis ≥70% (visual estimate), or ≥50% and <70% with evidence of ischemia. Evidence of ischemia includes any of the following:

   • Positive exercise stress test
   • FFR or QFR ≤0.8
   • Meets severe stenosis criteria by intracoronary imaging (IVUS or OCT): MLA <2.4 mm² for vessels with diameter <3.0 mm; MLA <2.7 mm² for vessels with diameter 3.0-3.5 mm; MLA <3.6 mm² for vessels with diameter >3.5 mm

3. Target lesion is a small-diameter predilation balloon (balloon diameter ≤1.5 mm), uncrossable and/or undilatable lesion (undilatable under stent post-dilation balloon rated burst pressure and/or special circumstances unsuitable for dilation), including calcified lesions, CTO lesions, in-stent restenosis, stent underexpansion, and high thrombus burden lesions.

4. Guidewire successfully passes through the true lumen of the target lesion without NHLBI type C or higher dissection.

Exclusion Criteria:

Clinical Exclusion Criteria:

1. Hemodynamic instability or severely reduced exercise tolerance (NYHA Class III or IV).
2. Severe heart failure with reduced ejection fraction (LVEF <30%).
3. Intracardiac thrombus on echocardiography within 30 days prior to enrollment.
4. Has received an organ transplant or is awaiting an organ transplant.
5. Currently receiving chemotherapy or scheduled to receive chemotherapy within 30 days before or after the baseline procedure.
6. Has a bleeding diathesis, contraindication to antiplatelet or anticoagulant therapy, or is unable to receive antithrombotic therapy.
7. Chronic renal insufficiency with serum creatinine >2.5 mg/dL (or 221 µmol/L).
8. Cerebrovascular accident (CVA), transient ischemic attack (TIA), or permanent neurological deficit that may preclude compliance with the protocol within the past 6 months.
9. Unconscious or requiring circulatory support or mechanical ventilation before PCI.
10. The target vessel (including side branches) has received any PCI within 1 month prior to the baseline procedure.
11. Planned interventional or cardiac surgical procedure within 30 days after baseline procedure.
12. Prior coronary intravascular brachytherapy at any time.
13. Allergy to medications or devices required during PCI (including but not limited to rapamycin, paclitaxel, dual antiplatelet agents, polyamide, polyurethane, PTFE, or stainless steel).
14. Other severe medical conditions (e.g., cancer, congestive heart failure) with life expectancy <12 months.
15. Current substance abuse or addiction (e.g., alcohol, cocaine, heroin).
16. Currently participating in another investigational drug or device trial that has not reached its primary endpoint, or planning to participate in another investigational drug or device trial within 6 months after the baseline procedure.
17. Plans to conceive within 6 months after baseline procedure.
18. Pregnant or breastfeeding women (pregnancy test required within 7 days before baseline procedure for women of childbearing potential).
19. The investigator determines that the subject is unsuitable for enrollment.

Angiographic Exclusion Criteria (visual estimate):

1. Target lesion meets any of the following criteria:

   -≥2 target lesions requiring treatment during the baseline procedure

   • Ostial lesion (within 3 mm of the ostium)
   • Medina type "x, x, 1" bifurcation lesion
   • Intimal dissection (NHLBI type C or higher)
   • Guidewire-uncrossable total occlusion
   • Severely angulated lesion

2. Unprotected left main coronary artery disease (>50% diameter stenosis).

3. The target vessel has other clinically significant lesions that may require intervention within 6 months after the baseline procedure.

4. Predicted inability to deliver the laser fiber catheter to the target lesion due to various reasons (e.g., severe proximal tortuosity of the target vessel).