Horton's disease is a giant cell arteritis well known for its presentation as temporal arteritis. It is, in fact, a systemic disease which affects over 1% of the general populations after 50 years of age. With the exception of the risk of blindness by occlusion of the ophthalmic artery, the cardiovascular manifestations of Horton's disease are not well known and probably underestimated by clinicians. The main complications are involvement of the large arteries, especially the thoracic aorta and subclavian and axillary arteries, the femoro-popliteal axis and supra-aortic arterial vessels. During the initial phase of the disease, extension of arteritis to the carotid and vertebral arteries is of particular concern because of the risk of cerebral infarction. The coronary arteries, myocardium, pericardium of pulmonary arteries may also be affected by the inflammatory process. In the long-term, Horton's disease may be complicated by aneurysms, dissection of parietal rupture of the thoracic aorta. Treatment is based on steroid therapy, sometimes associated with antiplatelet agents or anticoagulants during the initial phase of treatment. Long-term follow-up is justified because of the risk of late aortic complications.