Because the cavopulmonary shunt procedure is widely used for palliation of complex congenital heart diseases, pulmonary arteriovenous malformations (PAVMs) are relatively well-known complications. The reported patient was a 23-year-old woman who experienced PAVMs in the right lower lobe after a classical Glenn anastomosis and Björk procedure for tricuspid atresia. Her arterial oxygen saturation (SaO₂) 14 years after the Björk procedure was ~80 %. She then underwent a total cavopulmonary connection (TCPC) conversion to reduce her PAVMs in the right lower lobe using the “hepatic factor.” However, her situation remained unchanged, and she experienced severe systemic cyanosis (SaO₂, 70 %) and dyspnea during physical exertion without hemoptysis due to increased blood flow to the PAVMs. Although interventional embolization was considered, it was impossible due to considerable dilation of the main PAVM. Thus, right lower lung lobectomy was performed. After surgery, the patient’s SaO₂ increased to 90 %. To the authors’ knowledge, this is the first case report of a lung resection for residual PAVMs after TCPC conversion.