Radiotherapy-induced aortic valve disease associated with porcelain aorta.

Mediastinal irradiation has been reported to induce cardiac disease such as pericarditis, valvular dysfunction, conduction abnormalities, accelerated arteriosclerosis of the coronary arteries, and also calcifications of the ascending aorta. We herein describe a case of radiotherapy-induced porcelain aorta and aortic valve disease and their surgical treatment. The patient was diagnosed with myasthenia gravis (MG) in 1965 (Osserman's type II), and mediastinal irradiation was performed in 1970 for treatment of thymic tumor associated with MG. Thirty years after radiation therapy, complete atrioventricular block and aortic valve disease with severe calcification of the ascending aorta and aortic arch (porcelain aorta) were detected on echo cardiogram and cardiac catheterization. A permanent pacemaker was implanted via the left subclavian vein and aortic valve replacement was performed under extracorporeal circulation established by selective cerebral perfusion and balloon occlusion instead of aortic cross-clamping. As no risk factors of arteriosclerosis such as hypercholesterolemia, hyperglycemia and hypertension were apparent, we concluded that the aortic valve disease and porcelain aorta were primarily induced by radiotherapy.