This observational study aims to assess the effect of oral antiplatelet or anticoagulant drugs on key postoperative outcomes in patients with lower extremity varicose veins who have undergone radiofrequency ablation. Its main objectives are to determine the impact of these medications on postoperative 30-day bleeding risk and postoperative 3-month venous closure rate in this patient population. Researchers will compare three groups-patients receiving oral antiplatelet drugs, those receiving oral anticoagulant drugs, and those not receiving either type of drug-to identify differences in the two key outcomes. Participants will complete baseline data collection (including medical history, medication use, and lower extremity venous assessment) before or shortly after radiofrequency ablation, undergo 30-day postoperative follow-up to evaluate bleeding events (such as minor bleeding or major bleeding requiring medical intervention), receive venous ultrasound at 3 months postoperatively to measure venous closure rate, and report any medication changes or adverse events during the follow-up period.

Inclusion Criteria:

• Aged 18 years or older, with a confirmed diagnosis of primary lower extremity varicose veins (CEAP classification C2-C6) based on clinical examination and duplex ultrasound.
• Underwent endovenous radiofrequency ablation (RFA) of the great saphenous vein as the primary intervention.
• Postoperatively, either: (a) continuously uses standard-dose oral antiplatelet drugs (e.g., aspirin 100mg/day, clopidogrel 75mg/day) or oral anticoagulant drugs (e.g., warfarin with INR maintained at 2.0-3.0, direct oral anticoagulants at standard therapeutic doses) as per clinical routine, or (b) does not use any antithrombotic drugs.
• Able to understand and comply with the follow-up schedule (including 30-day bleeding assessment and 6-month duplex ultrasound examination) and provide informed consent.

Exclusion Criteria:

• Presence of secondary varicose veins caused by deep vein thrombosis, venous malformation, or other vascular disorders.
• History of coagulation disorders (e.g., hemophilia, thrombocytopenia with platelet count <100×10⁹/L) or use of other antithrombotic agents (e.g., low-molecular-weight heparin, glycoprotein IIb/IIIa inhibitors) postoperatively.
• Major bleeding events (e.g., gastrointestinal bleeding, intracranial hemorrhage) within 3 months prior to RFA.
• Severe hepatic insufficiency (Child-Pugh class C), renal insufficiency (eGFR <30 mL/min/1.73m²), or other life-threatening systemic diseases.
• Unable to complete follow-up due to mental disorders, mobility limitations, or other reasons, or refusal to sign the informed consent form.

The study population includes adults aged ≥18 years with confirmed primary lower extremity varicose veins (CEAP classification C2-C6), validated by clinical examination and duplex ultrasound, who have undergone endovenous radiofrequency ablation (RFA) of the great saphenous vein as the primary treatment. Participants are stratified into three groups based on postoperative antithrombotic medication use per routine clinical practice: those taking standard-dose oral antiplatelet drugs, those using standard oral anticoagulants, and a control group without antithrombotic agents. Excluded individuals are patients with secondary varicose veins (e.g., due to deep vein thrombosis or venous malformations), coagulation disorders, postoperative non-oral antithrombotic use, major bleeding within 3 months before RFA, severe hepatic/renal insufficiency, life-threatening systemic diseases, or those unable to complete follow-up or provide informed consent.