Radiation-Induced Coronary Artery Disease Manifested at Very Late Phase

Abstract

SummaryWe report the case of a 51-year-old female, in whom coronary artery disease such as occlusion of septal perforators was manifested, on the occasion of hospitalization with congestive heart failure. The patient had a history of radiation therapy for a mediastinal tumor 19 years previously. As she had no conventional coronary risk factors, the cause of the coronary artery disease is thought to have been related to the radiation therapy. As survival rates of cancer patients improve as a consequence of therapeutic advances, we should be aware of the possibility of coronary artery disease as a very late complication of radiation therapy, even in patients who have no coronary risk factors.(Int Heart J 2017; 58: 993-997) Key words: Radiation therapy, Very late complication, Cardiovascular complication, Heart failure R adiation therapy has an important role as a mode of therapy for malignant tumors. When the irradiation is performed for lung, breast, or esophageal cancer, or for mediastinal tumors such as malignant lymphoma, other intrathoracic organs including the heart are also exposed to the radiation. This can cause coronary artery disease, constrictive pericarditis, valvular disease, and cardiomyopathy in the late stages.1) As the survival rates of intrathoracic malignant neoplasms have been improved by recent therapeutic developments, radiationinduced cardiovascular disease may become more common. Here we report a case with coronary artery disease manifested 19 years after radiation therapy for a mediastinal tumor. Case ReportA 51-year-old female suspected of having congestive heart failure was admitted to our hospital. She had a history of a mediastinal tumor, where information of histopathological diagnosis was absent, but she had received radiation therapy at a total dose of 64.8 Gy ( Figure 1A, B), 19 years previously. She had been experiencing palpitations and shortness of breath for six months, during which time the symptoms had gradually worsened. She had also been having attacks of nocturnal dyspnea at increasing frequency for the past month. On admission, her heart failure symptoms corresponded to New York Heart Association (NYHA) Class III. Her temperature, heart rate, and blood pressure were 36.1ºC, 120 beats/minute, and 148/94 mmHg, respectively. Jugular venous dilatation and edema of the lower extremities were absent. Blood oximetric oxygen saturation was 92% when breathing room air. A Levine II/VI pansystolic murmur and third heart sound were audible maximally at the apex.At admission, a chest roentgenogram showed mild pulmonary congestion and elevation of the left diaphragm, but no cardiomegaly (Figure 2A). An electrocardiogram had showed regular sinus rhythm and narrow QRS complex waves 3 years before ( Figure 2B), but complete left bundle branch block was present at admission. Figure 2C shows the electrocardiogram 2 days after admission. Blood cell counts and clinical chemistry were within the normal range, including levels of total cholesterol, triglycerides, and hemoglobin A1c (187 mg/dL,...