Arterial involvement is rare in Behçet's disease but can be at the forefront of the clinical picture and cause life-threatening complications. Case reports. A 36-year-old man had Behçet's disease with an aortographically documented aneurysm of the abdominal aorta as the inaugural manifestation. He had oral and genital ulcers. Funduscopy showed periphlebitis. In a 38-year-old man with an 8-year history of Behçet's disease, pulmonary and coronary artery aneurysms developed, as well as intracardiac and venous thromboses. Discussion. Arterial involvement occurs in 3-5% of patients with Behçet's disease and usually manifests as multiple spindle-shaped aneurysms. Intracardiac thrombosis and cardiac aneurysm are exceedingly rare. Our patient had an extremely unusual presentation given the low rate of occurrence of arterial lesions in Behçet's disease. Conclusion. Arterial involvement in Behçet's disease raises treatment challenges because the lesions tend to recur and can cause life-threatening complications.