Autopsy of the body of a 62-year-old man shows a supravalvular aortic rupture with cardiac tamponade. Histology of the ascending aorta detected infiltrations of lymphoid, plasma, and epithelioid cells in its tunica externa and tunica media, while there are necrotic foci in the tunica media, and proliferation of adventitial cells, endotheliocytes, and vessels in the tunica externa. Such changes in the aorta are characteristic of: