<s>[INST] My father is 77. He needs triple bypass. He has begining stages of dementia. He had brain surgery for an aneurysm 23 years ago. Cardiologist says surgery needed.One artery completely blocked one 90% and 60%. Will this affect his dementia . Brain surgery was a miracle although it affected short term memory at time. Over years he lost his mother, sisters and grandson and never cried or showed emotion. How will this affect his quality of life? [/INST] Hi, Thank you for asking to Chat Doctor, In subjects with dementia undergoing a surgery on most cases deteriorates the condition. The main reason is blood hypoperfusion during any kind of surgery. Then having in consideration your father past medical history of cerebral aneurysm this is another negative factor. I would advise you to have an appointment with your doctor to thoroughly discuss the possibility of other options for treatment or other ways how to levitate this problem. Hope this will help with the solution of your problem, feel free for any other information. </s>