Aortic pulmonary fistula, a rare complication of an aortic aneurysm, can potentially cause multiple complications, and it is often fatal. A young male, who had a history of aortic valve replacement, was hospitalized due to recent dyspnea. The diagnosis was an aortic pulmonary fistula, but the patient unfortunately passed away before surgery could be performed. Even though the prognosis for these patients is generally poor, early detection and appropriate management can potentially save lives. Meanwhile, it is essential to assess the aorta when treating aortic valve disease. Aortic pulmonary fistula, a rare complication of aortic aneurysm, can lead to a variety of complications including rapid left-to-right shunt, right heart failure, and mortality. It is a congenital heart defect that manifests early in life, but can also be acquired in conditions such as atherosclerosis, syphilis, post-endocarditis, and rheumatic diseases like Marfan's syndrome.