Good to hear that your mom is doing better.
I will preface this by saying that I am not a cardiologist (and didn't sleep in a Holiday Inn Express). From what you say, it sounds like she may have congestive heart failure and/or pulmonary edema. Most of the time these can be treated with medicine with an occasional need for surgery if there is a leaky heart valve.
I have a talent for taking "doctor speak" and translating it into English. I may have to study up on the condition first, but I can usually make it make sense.