title: Complete atrioventricular block following radiation therapy for malignant thymoma.
abstract: Complete atrioventricular block following radiation is very rare. We present a case which developed after radiation therapy for malignant thymoma. The etiology of conduction disturbances due to radiation is unknown. In our case, serial electrocardiograms showed stepwise progression of the conduction disturbance, and His bundle electrocardiograms revealed new prolongation of the H-V interval. Endomyocardial biopsy specimens demonstrated occlusion in small arteries and diffuse degenerative changes in the myocardium. We therefore attributed the complete atrioventricular block in our patient to secondary damage to the conduction system, caused by radiation-induced occlusive changes in the small arteries supplying the conduction system.
authors.affiliation: Department of Internal Medicine, Ishikawa Prefectural Central Hospital, Kanazawa, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Nakao
authors.forename: H
authors.initials: H
authors.lastname: Kanaya
authors.forename: M
authors.initials: M
authors.lastname: Namura
authors.forename: K
authors.initials: K
authors.lastname: Ohsato
authors.forename: T
authors.initials: T
authors.lastname: Araki
authors.forename: T
authors.initials: T
authors.lastname: Ohka
authors.forename: N
authors.initials: N
authors.lastname: Sugihara
authors.forename: R
authors.initials: R
authors.lastname: Takeda
mesh_terms: D000368:Aged; D004562:Electrocardiography; D006327:Heart Block / Q000000981:diagnostic imaging / Q000209:etiology*; D006801:Humans; D008297:Male; D013902:Radiography, Thoracic / Q000009:adverse effects; D011877:Radionuclide Imaging; D013945:Thymoma / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D013953:Thymus Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D014057:Tomography, X-Ray Computed