A 65-year-old female presents to the emergency department with a four-hour history of sudden onset of right leg pain, coolness, weakness, and numbness. She has no prior similar history. The pain began while she was sitting watching television. She has a history of hypertension and hypercholesterolemia and takes medication for both. She denies smoking. On review of systems, she has no prior history of pain in her right leg with walking. On physical examination, her lungs are clear to auscultation. Her heart rate is irregularly irregular without murmurs, rubs, or gallops. Her abdomen is soft and non-tender without a pulsatile mass. On the left side, the femoral, popliteal, dorsalis pedis, and posterior tibial pulses are 2+, with biphasic signals on Doppler. On the right side, the femoral, popliteal, dorsalis pedis, and posterior tibial pulses are absent, with faint monophasic signals on Doppler. Her right calf is tender to palpation but is not edematous. She has normal appearing, supple skin in her legs with a normal hair pattern. The left foot is pink and warm with a two-second capillary refill and normal motor and sensory function. Her right foot is pale and feels much colder than the left; capillary refill time is six seconds. The toes have decreased sensation to touch. Her strength is diminished in both plantar flexion and dorsiflexion of the ankle at 4+/5.