Get a second opinion. Not that the treatment offered will be much different. The docs all want to treat me as a patient with heart disease and other diseases. I, like you, have no heart disease or co-morbidities. No high blood pressure, no diabeties, not over weight, control sodium to under 1500mg daily by diet, exercise 5-6 days, 180-200 minutes weekly. My heart failure is diagnosed as idiopathic cardiomyopathy with LBBB causing erratic PVCs that often exceed 10%-35% of my beats in any given minute. This means my heart failure has no known cause. Two cardilogists told me, one from the Mayo, that is is likely caused by a unknown virsus. Covid??. I looked it up people like us represent .28% of women in this country diagonosed with heart failure. The docs are treating us with medicines developed for the 99.72% of the HF women patients. I keep advocating for the least treatments that won't jeapardize my excellent health with drugs that are not proven to help my condition.

Yes I’m in the same boat - no other symptoms RT heart disease. I am breathless upon exertion and have qualified for a portable oxygen concentrator.
I have a concentrator for nighttime use and that’s improved my sleep enormously.

This was helpful in that I appreciate having similar company on this journey. Already, reading your and Dizzy’s comments, I have a broader perspective on the disorder.
It’s interesting to me that Cleveland Clinic has an entire department for HFpEF. Not sure what research may be coming out of there. Wish they had a support group like this too! I like the thought of getting a second opinion from them, but road trip from CT not in my wheelhouse.