A case of a 41 years-old-man, who had undergone surgical intervention ten years previously for aortic valve replacement in ECC with the coronary perfusion technique, is reported. This patient was studied because of the appearance of angina pectoris three months after the intervention and its progressive development. Selective left coronary angiography showed an ostial subocclusive stenosis; the run-off from the right coronary artery provided distal blood supply to the left coronary artery. A venous bypass was implanted between the aorta and the left anterior descending branch; the prosthesis was substituted because it was altered and caused hemolysis' problems. In accordance with most Authors late ostial coronary stenosis is a complication of the coronary perfusion technique, which is adopted for myocardial protection during surgical interventions for aortic valve replacement.