TA occurs most commonly in young women (female/male ratio 8:1). The median age of onset is 25 years, but 25% of cases occur before age 20 years and 15% occur after age 40 years. TA occurs most commonly in Asian (Japan, China, India, SE Asia) females but has been reported worldwide in all racial groups.
Symptoms occur primarily as a result of stenoses of the aorta and its branches. A comprehensive vascular examination (BP, pulse, bruits) in both arms and legs is mandatory. The aortic arch and abdominal aorta are most commonly affected. Upper-extremity and thoracic vessels (subclavian, carotid, vertebral) are more commonly involved than iliac arteries. Pulmonary artery involvement can occur in up to 70% of patients, with <25% having symptoms of pulmonary hypertension. Cardiac involvement with angina, myocardial infarction, heart failure, sudden death, and aortic valvular regurgitation occurs in up to 15% of patients.
Angiography is the gold standard for detecting arterial involvement in TA. However, MRA and CTA are noninvasive tests that are replacing catheter angiography and can also detect vessel wall thickness. The lesions of TA are most often long-segment stenoses or arterial occlusions of aorta and visceral vessels at their aortic origins. Aneurysms can occur.
High-dose corticosteroids are the initial therapy for active inflammatory TA. Corticosteroids are maintained at high doses until symptoms and laboratory evidence (ESR, CRP) of inflammation normalize.