Restrictive Cardiomyopathy in young, thin, non-diabetic female

What can cause impaired left ventricular relaxation in a 40 year female who is thin, not diabetic, and not hypertensive? She has EDS and POTs, and symptoms of carcinoid syndrome, but octreotide scan showed no carcinoid tumors. A subtotal colectomy that was done about 4 months ago psthology found a carcinoid tumor just under 1 cm in size. Her pulse and BP vary greatly between standing and lying down. Standing pulse is ~150-180 and when supine sometimes is ~ 40-50. Supine BP is between 120/70 - 135/80. Standing BP may drop to 70/40. ~2 months ago she started DDAVP and Octreotide and those have helped her substantially, however, she still has a very low exercise tolerance, shortness of breath wiht only little exertion, and some syncope.
Could she still have carcinoid tumors in spite of the negative octreotide scan and is there a better scanning technique than an octreotide scan for detecting carcinoid tumors? Could the carcinoid syndrome (started about 3 years ago) have caused the cardiomyopathy? Could any of the heart dysfunction be the result of EDS or something congenital? What might the prognosis be for this if the carcinoid is resolved? She sometimes has bundle branch blocks
Report Summary is:
1 Mildly to moderately decreased left ventricular function
2 LV ejection fraction estimated to be 40 to 45%
3 Impaired relaxation pattern of LV diastolic filling
4 Mildly dilated left atrium
5 Increased e point septal separation

She was told that this indicates that she has restrictive cardiomyopathy. Is hypertrophy inherent?
She is my sister and I am concerned.

[Cleveland Clinic]

The sensitivity of Indium-111 labeled Octreotide Scan is only 60%, and the specificity is  90% which means that this not a good screening test, and hence given the high pre test probability of metastatic disease ( she has carcinoid syndrome which occurs in 10% of carcinoid tumors and implies metastasis beyong the lung) it would be better to reimage her with either I-Labeled Meta-iodobenzylguanidine (MIPG) or with a whole body \Positron Emission Tomography (PET Scan).
The findings on the echo are consistent with carcinoid heart disease, which can be reversible if the tumor and its secretants are removed.  

[sofa weight]

Thank you for hte response. I forgot to check back for the answer until now, but am glad that I checked back. We still didn't have an answer to the situation and so I appreciate you answering. She always finds my answers on here before I do an so she told me the answer was up here. Again, Thanks so much for the response.

[sofa weight]

Can we get those tests run at Cleveland clinic? I asked my sister about these and she said that where she is, they don't have the right contrast, or what ever the word is for the tagged molecules. Also, is there anyh special kind of a pet scan she should get or just plain ol generic pet scan?
I'm tryin to get her to get the pet scan, but she says she needs the other scan and where she is doesn't ahve that kind. However, she told me that if I can find a place that can do the right tests, then she will go there. So, can she get teh right tests in cleveland at the cleveland clinic?