Thank you Teresa. The NP Pulmonologist suggested a cardio pulmonary stress test (Is that the right term?), the one where I do the stress test while they draw blood. My rheumotologist, neurologist, and GP were all unfamiliar with this, and they didn't order one. They said the Pulmonologist needs to order it, but the pulmonologist (NP) said she wouldn't since there was no pulmonary problem. I will keep pursuing this.
This type of test should probably be ordered by your cardiologist. If your other doctors were unfamiliar with the test. why not print off a copy of the article at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2734442/.
By the way, do you live near any of the hospitals listed in the link I sent, https://health.usnews.com/best-hospitals/rankings/cardiology-and-heart-surgery ?