Sarah Rosenthal, a 63-year-old woman, has been a smoker for many years and has noticed a gradual reduction in her exercise tolerance over the last three years, finding it more difficult to garden and to walk to her synagogue. She has been able to modify her activities in response to the limitations imposed by her breathlessness but her family has noted her weight has been increasing. When her family noticed that her legs were becoming more swollen and that she was not as "sharp" as usual, they decided to bring her to the emergency room. Her family reports that Sarah has recently visited her family physician and was prescribed a diuretic for her ankle swelling.