What is the treatment for mitral valve regurgitation?

My 98 year old mother was diagnosed with mitral valve regurgitation. She was placed on lasix and after 4 weeks became dehydrated as evidenced by an unexplained rash and itchiness on scalp and chest. Went to a dermatologist and the physician did not find any bug source, being that my mother resides in a nursing home. My mother s BUN rate was 90 but after being hospitalized for the past 2 days and hydrated with an IV is lowering now to 50. Her creatine level is normal as well as her glucose leves. Blood pressure is normal -146/72. They discovered a UTI for which the doctors are administering rocephin until they specify the exact bacterium. Results should be back today. She is on Celexa for mood elevation - which is questionable as to its efficacy (40mg daily for the past 2 years). A catscan yesterday revealed an enlarged liver which is pressing on the pancreas. They want to do an ercp scope to rule out gall stones - which she has no history of - what other tests should we run.