@waterhopper- I'm not a medical professional but I had never heard of a vascular dysfunction until reading this article. However, I have personally experienced vascular disease. The symptoms sound the same but I don't know if it the exact same condition.
Mine started with angina symptoms and chronic fatigue. It ended up that I had blocked arteries. After a while, my legs started getting cramps in them quite often. My doctor said that it was peripheral vascular disease and had the same cause as the blocked arteries, just in a different area. I would suggest that your aunt see a cardiologist and perhaps go a little more in depth with her testing.