The retrospective analysis was performed of 26 patients (5 women and 21 men), mean age of 47.04 years, surgically treated for aortic dissecting aneurysm (ADA) at the Clinic of Cardiosurgery of the M.M.A. in the period 1988-1990. In the postoperative course acute renal insufficiency (ARI) has developed in 13 (50%) patients: of milder form in 5 (38.4%), medium in 6 (46.1%) and advanced form in 2 (15.3%) patients. The most common precipitating factor in development of ARI has been arterial hypotension (92.3%). In all patients including the patients treated by hemodialysis, it has come to complete recovery of renal function.