BACKGROUND People with Hodgkin's disease and breast cancer often receive therapeutic irradiation to the chest (mediastinum) as an element of treatment. While the therapy often cures the malignancy, it has been implicated in causing late-onset heart disease that may influence the provision of dental treatment. METHODS The authors conducted a MEDLINE search of the years 1995 through 2002 using the key terms "Hodgkin's disease," "breast cancer," "radiation therapy," "cardiac valves" and "coronary artery" to define the pathophysiology of the disorder, its epidemiology and dental implications. The articles they selected for further review included those published in English in peer-reviewed journals. RESULTS Therapeutic irradiation of the chest results in the inadvertent inclusion of the heart within the irradiation field. Over the next 10 to 20 years, some of these people may experience pathological changes of the heart valves that could predispose them to endocarditis, accelerated atherosclerosis of the coronary artery that heightens their risk of experiencing a fatal myocardial infarction or both. CONCLUSIONS Dentists need to identify patients who have received therapeutic irradiation to the chest and consult with the patients' physicians to determine whether the therapy has damaged the heart valves or coronary arteries. Patients with radiation-induced valvular disease may require prophylactic antibiotics when undergoing specific dental procedures that are known to cause a bacteremia and a heightened risk of developing endocarditis. Patients with radiation-induced coronary artery disease should be administered only limited amounts of local anesthetic agents containing a vasoconstrictor, and they may require the administration of sedative agents and cardiac medications to preclude ischemic episodes.