Radiation-induced valvular disease is the logical consequence of irradiation.

Mediastinal irradiation has been reported to induce cardiac diseases such as pericardial disease, accelerated arteriosclerosis of the coronary arteries, valvular disease, conduction abnormalities, and calcification of the aorta. We experienced four cases of radiation-induced valvular disease. All patients had histories of radiation therapy and had aortic valve disease. All patients had marked fibrosis of the mediastinum and hypertrophy of pericardium. The aortic valve leaflets were tricuspid and fibrotic with focal dystrophic calcification and markedly thickened. In the pathological findings, certain rheumatic endocarditis changes such as endocardial reduplication and vascularization were not found in all aortic valves. The mechanism of radiation-induced cardiac disease is not clear. However, those changes seem to progress very slowly. Thus, long-term follow-up care is particularly important for patients undergoing radiation therapy. Fortunately, today's irradiation techniques are much less harmful; therefore, radiation-induced cardiac disease will likely become more rare in the future.