I am an RN, not a doctor, just to be clear. So, I will be giving Nursing perspective
An enlarged heart is a symptom that the heart is being asked work harder than it is capable of. One of the ways the heart reacts to the increased demand is by enlarging.
Some of the things that increase demand on the heart are being overweight and smoking. This is a good reference about enlarged hearts that explains things very well and it is from a recognized and reliable source.
http://www.mayoclinic.com/health/enlarged-heart/ds01129
A trip to WDW is a wonderful incentive to do the this she needs to change to get healthy. But, it likely took her many years to get into her present situation, and quitting smoking and weight loss are not quick and easy things to change. So, even if she gets into shape to go to WDW, that doesn't mean she will be ready to do 9-12 miles of walking per day.
An
ECV or wheelchair would be a good choice to help her conserve energy and keep the demands on her heart lowered.
Post 2 of the disABILITIES FAQs thread has information about renting wheelchairs and
ECVs. You can find that thread near the top of this board or follow the link in my signature.
If she is really nervous about driving an ECV, it may be best to get a wheelchair instead - stress increases the heart rate. And, although using an ECV is not physically tiring, it requires alertness and it can be tiring to remain alert all the time.
A wheelchair and, in most cases an ECV, can be brought all the way in line to the boarding area. She may want to leave the wheelchair or ECV parked with the strollers for some attractions, but should be aware that some of the lines are long distance to walk, even if the wait is short.
There is more information on using and ECV, transferring and the lines in posts 18-22 on page 2 of the disABILITIES FAQs thread.
There are a few attrations with stairs - if she chooses to walk into those, she should get a Guest Assistance Card to bypass the stairs. There is more information about Gues Assistance Cards in post 6 of the disABILITIES FAQs thread ( she won't need one to use a wheelchair or ECV in lines/attractions.
For attractins with warnings, post 23 of the disABILITIES FAQs thread has a full list from the WDW park maps. I also included information in that post about why the attraction probably has the warning.
WDW uses a sort of generic and all inclusive warning. Attractions either have that warning or don't have a warning at all ( other than Soarin' which has a warning about fear of heights ).
Some people choose to avoid anything with a warning; for example, my father in law avoided anything with warnings because he had high blood pressure. Even if you do that, there are still plenty of things to see.
But, not every part of the warning applies to every attraction with a warning.
For example, Kali River Rapids, Kilimanjaro Safari and Expedition Everest at AK all have warnings.
Kali River Rapids is a turbulent, high speed ride on a free floating raft. It can raise heart rate and blood pressure because of all the unexpected turns and you can get suddenly drenched with cold water. The raft also sometimes comes down hard after going down a rapids. I would not recommend that attraction for anyone who has any of the warnings.
Kilimanjaro Safari is a mostly slow ride over rough roads. There are a couple of sort of scary parts, where you go over rickety bridges and go fast to 'chase' poachers, but those would probably not raise blood pressure or heart rate for most people because they know they are part of the show. Because the roads are rough and have bumps and potholes, there can be sudden jostles or bumps that might be a concern for people with neck or back problems. Also, if your ride tram breaks down, you will need to wait to be evacuated and the steps down are kind of high. So, most people with heart or blood pressure problems would be fine with that attraction.
Expedition Everest is a high speed, ride on a runaway railroad car. The whole attraction is based on it being 'out of control' with changes of direction and scary factor. So, that would probably not be a good choice for someone with the problems on the warning, although it is pretty smooth, so many people with back problems report they can ride it.
If she wants to ride some attrations with warnings, I would have her talk to her doctor about what sorts of things to avoid. There may be some very specific guidelines and, if so, I would try to pick out which attractions don't have those things.
I would personally not bother with trying to show videos to the doctor because I don't think that would be particularly helpful. Most of the dark attractions don't show up well on video and videos can be misleading - making things look more or less intense than they actually are. Without actually experiencing some of them, it's hard to tell what they would be like.
If there are some you are not sure of, you can ask the CM at the entrance for more information or ask to have one of your party actually do the attraction to check it out ( choose wisely - we don't have my DH check things out because he thinks all the roller coasters are "nothing - a piece of cake."
