Cardiac rehabilitation may not play a major role in raising your mother-in-law's EF, but it should improve her quality of life and her ability to be active. EF is a
helpful marker for physicians, but it isn't the be-all and end-all of rehabilitation. Some patients feel good and remain active in spite of having a low EF. The real goal is to improve your mother-in-law's health and quality of life.
That said, your mother-in-law's EF may rise over the next few months as a result of the surgery, which should improve blood flow to her heart. Her return to activity should be gradual, so it's helpful to have the close follow-up that's available in a cardiac rehabilitation program. The program will also provide emotional support and patient education. Three days a week is a good start, and her doctor will provide recommendations for appropriate levels of activity at other times.