Circulatory distress can occur in the long term after the formation of a traumatic arteriovenous fistula (AVF), but cardiac failure rarely occurs in a patient with an AVF in the lower extremity. The present patient underwent surgery to treat a traumatic popliteal AVF 9 years after sustaining the injury. Although the patient was asymptomatic with regard to cardiac circulation, cardiomegaly was noted and it resolved promptly after the surgical treatment. Cardiac insufficiency should be borne in mind even when a patient is asymptomatic because young patients have a high tolerance for cardiac overload.