The objective of this clinical evaluation is to evaluate the immediate and long-term (up to 12 months) outcome of NanoCrossTM balloon catheter (Covidien) in a prospective, non-randomised, controlled investigation for the treatment of patients with critical limb ischemia (Rutherford 4-5) due to the presence of lesions of minimally 10cm in length at the level of the below-the-knee arteries.

Inclusion Criteria:

• Patient presenting with rest pain or minor tissue loss (Rutherford class 4 or 5)
• Patient is willing to comply with specified follow-up evaluations at the specified times
• Patient is >18 years old
• Patient understands the nature of the procedure and provides written informed consent, prior to enrolment in the study
• Patient has a projected life-expectancy of at least 12 months
• Patient is eligible for treatment with the NanoCrossTM .014 balloon catheter (Covidien)
• Male, infertile female, or female of child bearing potential practicing an acceptable method of birth control with a negative pregnancy test within 7 days prior to study procedure
• De novo lesion or restenotic lesion after PTA in the infrapopliteal arteries,suitable for endovascular therapy
• Total target lesion length minimally 100mm
• Target vessel diameter visually estimated to be >1.5mm and <4.0mm
• Guidewire and delivery system successfully traversed lesion
• At least one non-occluded crural artery with angiographically documented run- off to the foot.

Exclusion Criteria:

• Patient refusing treatment
• The reference segment diameter is not suitable for the available balloon design
• Untreated flow-limiting inflow lesions
• Perioperative unsuccessful ipsilateral percutaneous vascular procedure to treat inflow disease just prior to enrollment
• Any previous surgery in the target vessel (including prior ipsilateral crural bypass)
• Aneurysm in the target vessel
• Target lesion has severe calcification as determined by physician's discretion
• Non-atherosclerotic disease resulting in occlusion (e.g. embolism, Buerger's disease, vasculitis)
• Severe medical comorbidities (untreated CAD/CHF, severe COPD, metastatic malignancy, dementia, etc) or other medical condition that would preclude compliance with the study protocol or 1-year life expectancy
• Major distal amputation (above the transmetatarsal) in the study limb or non- study limb
• Septicemia or bacteremia
• Any previously known coagulation disorder, including hypercoagulability
• Contraindication to anticoagulation or antiplatelet therapy
• Known allergy to contrast media that cannot be adequately pre-medicated prior to the study procedure
• Patient with known hypersensitivity to heparin, including those patients who have had a previous incidence of heparin-induced thrombocytopenia (HIT) type II
• Currently participating in another clinical research trial
• Angiographic evidence of intra-arterial thrombus or atheroembolism from inflow treatment
• Target lesion access not performed by transfemoral approach.