Right Ventricular Outflow Tract Obstruction Due to Immunoglobulin G4-Related Disease.

A 64-year-old man with extensive tumorous infiltration of the pulmonary valve underwent partial resection of a tumor of the right ventricular outflow tract and replacement of the affected valve. A diagnosis of immunoglobulin-G4 related disease of the heart was made based on the immunohistologic findings. One year after the surgical resection, growth of the tumorous mass was observed, and steroid therapy was initiated. He had no sign of tumor progression four years after the steroid therapy.