Investigation of Femoropopliteal In Situ Valve Formation With the InterVene System (INFINITE-US)

Key Inclusion Criteria * Failed at least 6 months of conservative therapy at some point during the course of their CVI management (symptoms not adequately resolved or patient non-compliant/unable to tolerate) * Deep system venous reflux characterized by \>1 second reflux time in two vein segments (vein segments defined as: proximal femoral, distal femoral, and popliteal), as assessed by duplex ultrasound (DUS) with patient in the standing position * Presence of at least two potential target sites within a target vessel as assessed preliminarily by DUS, with a target site being defined as a segment within the femoral or popliteal vein that is: 7mm to 11mm in luminal diameter and at least 3cm long and absent features that, in the Investigator's opinion, would preclude formation of a monocuspid valve (at any orientation). * In the Investigator's opinion, the subject is a good candidate for treatment with the BlueLeaf System based on their symptoms, quality of life, anatomy, and the likelihood of benefit from continued conservative therapy Key Exclusion Criteria: * Untreated significant superficial venous incompetence which, in the opinion of the Investigator, may be the primary source of existing symptoms * Acute deep venous thrombosis (DVT) within 1 year of consent * Deep venous intervention (includes stenting) in the target limb or outflow vessels within 3 months of consent * Flow-limiting venous outflow obstruction central to the intended target sites, defined by a common femoral vein duplex exam found to have a continuous waveform without respiratory variation * Contraindications to all protocol specified anticoagulation options * Known and uncontrolled hypercoagulopathy (i.e. hypercoagulopathy that cannot be adequately managed/controlled with medication) * Women on long-term oral contraceptives * Non-ambulatory patients * Significant peripheral arterial disease with an ankle-brachial index of \< 0.70 or with incompressible vessels * New York Heart Association Class III or IV heart failure * Patients with a history of right heart failure occurring as a consequence of, for example, biventricular failure, intrinsic pulmonary disease, chronic thromboembolic pulmonary hypertension, and other etiologies that result in elevated right-sided pressures. * Active systemic infection * Invasive surgical procedure within the last 3 months that in the Investigator's opinion would interfere with the study procedure or results * Chronic renal insufficiency with creatinine level of ≥ 2mg/dL * Hemoglobin level \< 9.0 mg/dL * Platelet count \< 50,000 or \> 1,000,000/mm3 * Total white blood cell count \< 3,000/mm3 * Subject is enrolled in another clinical study that, in the opinion of the Investigator, may conflict with this study or compromise study results * Comorbidity risks or other concerns which, in the opinion of the Investigator, either limits longevity or likelihood of complying with the protocol and its prescribed follow up (e.g. recent cancer or stroke); or precludes patient from being transitioned to open surgery if complication requiring surgical intervention occurs during the procedure (such as severe vein laceration).