Thanks for your question on Health Care Magic. I can understand your mother s situation and problem. She should definitely under go mitral valve replacement. She is already having severe MR (mitral regurgitation) and mild MS (mitral stenosis). With time her MS will be more worse and cause fixed mitral valves. This situation can cause sudden heart failure and sudden death. This is inevitable complication of rheumatic heart disease in later stages of life. So to prevent this, better to get done mitral valve replacement at present. This operation is needed in her case to prevent future life threatening complications. No role wait and continuing medical treatment. Hope I have solved your query. I will be happy to help you further. Wishing good health to your mother. Thanks.