Abstract： Objective To evaluate the CT features of aorto-right atrial fistula after aortic valve replacement(AVR) or ascending aortic replacement.Methods Eighty-seven patients with aortic-right atrial fistula underwent CT after operation.The CT features were retrospectively analyzed.Fistula was measured according to maximum width of the shunt.Results Aorto-right atrial fistula was detected in 87 patients after aortic valve replacement or ascending aortic replacement by CT scan. Among them,25 patients were diagnosed as mild aorto-right atrial fistula,47 patients as moderate,and 15 patients as severe.Thirty-seven patients underwent follow-up CT.Among them,10 patients with mild to moderate aorto-right atrial fistula were considered to have complete regression,8 patients with mild aorto-right atrial fistula considered to have incomplete regression,14 patients with mild to moderate aorto-right atrial fistula considered to have stable condition,and 5 patients with moderate aorto-right atrial fistula considered to have progression at the 3-month follow-up.Conclusion CT is a useful tool for defining aorto-right atrial fistula after AVR or ascending aortic replacement and for evaluating it in follow-up.