A 20-year-old woman complains of double vision, fainting spells, tingling of the fingers of her left hand and numbness of the fingers of her right hand. Physical examination reveals absence of pulse in her right arm. Laboratory tests show elevated erythrocyte sedimentation rate and thrombocytosis. An aoogram demonstrates narrowing and occlusion of branching aeries, including the right subclan aery. The patient subsequently develops hea failure and dies of massive pulmonary edema. At autopsy, the aoa has a thickened wall and shows vasculitis and fragmentation of elastic fibers. Which of the following is the most likely diagnosis?