Right ventricular outflow tract obstruction caused by a foreign body granuloma originating from a Dacron^® graft 30 years after transannular patching

A 43-year-old man with a surgical history of atrial septal defect (ASD) patch closure and transannular right ventricular outflow tract (RVOT) reconstruction using a Dacron^® patch 30 years ago visited our hospital due to dyspnea on exertion (NYHA class II), which started 4 months prior to presentation.