A 60 year man had undergone cardiac bypass surgery 1 month back. Now he staed forgetting things and was not able to recall names and phone numbers of his relatives. What is the probable diagnosis?

This patient is showing features of cognitive dysfunction following cardiac surgery. Postoperative cognitive dysfunction can occur in 20-30% of patients 1 month after surgery. Patients develop changes in personality, attention and memory.The etiology is multi factorial and includes cerebral microembolization, global cerebral hypo perfusion, systemic and cerebral inflammation, cerebral temperature peurbations, cerebral edema, and possible blood-brain barrier dysfunction. It can be assessed by a battery of psychometric tests typically before and after surgery. These tests evaluates attention, sho and long term memory, visuomotor function and other cognitive domains. Ref: Cardiothoracic Surgery in the Elderly By Mark R. Katlic, page 58; Case-Based Anesthesia: Clinical Learning Guides By George Shoen, page 35-7; The Annals of Thoracic Surgery Volume 59, Issue5, May 1995, Pages 1326-1330.