BOLD MRI as a Surrogate of Improved Muscle Oxygenation Following Endovascular Therapy for the Treatment of CLI

This study is a prospective single arm, open label registry to evaluate the feasibility of blood oxygen level dependent (BOLD) magnetic resonance imaging for the assessment of a potentially new functional surrogate of altered lower limb skeletal muscle oxygenation after a successful percutaneous endovascular intervention. Baseline MRI assessment using the BOLD technique will be performed on qualified subjects prior to undergoing a standard of care endovascular therapy. Post-procedure BOLD-MRI assessment will also be performed at 30 days and either 90 or 180 days post-procedure. Post-MR image acquisition processing and analysis will be performed, using pre-determined algorithms, by a core laboratory.

Inclusion criteria

• Age > 18 and < 90 years
• Subject has been informed of the nature of the study and agreed to participate and has signed an IRB approved consent form
• Subject understands the duration of the study and its follow-up visit requirements and agrees to comply
• Subject has documented chronic limb ischemia in the target limb with Rutherford Category 2-5 and pulse plethysmography (PPG), pulse volume recording (PVRs), TcPO2, ABIs or toe pressures and symptoms that conform to the diagnosis of life-style limiting claudication or critical limb ischemia

Exclusion criteria

• Adult subjects who lack the capacity to consent for themselves
• Women who are pregnant or wish to become pregnant during the course of the study. (Women of child-bearing potential must undergo pregnancy testing at the time of enrollment, and be counseled in appropriate measures to avoid becoming pregnant for the duration of the study)
• Subjects with contraindications to MR imaging procedures (including the administration of gadolinium based contrast agents)
• Subjects suspected to be unable to withstand the reactive hyperemia protocol