Valvular disease and chest pain

I am a 49 yr old female nurse. In July I was referred to the rapid access chest pain clinic following episodes of chest pain brought on by exercise. The cardiologist detected an ejection systolic murmur and ordered a CT Angiogram and echocardiogram.
The dr who did the echo asked me if I had ever lived or worked in a third world country and when I told him I has spent time in Namibia 8 yrs previously he told me that might explain what he had found.
The results were sent to my GP who told me I has aortic schlerosis and that I would be monitored in the valve clinic. Meanwhile I am still waiting for the results of the CT Angiogram done in September.
I received an appointment today for NM Cardiac rest mibi/tf scan and adenosine stress mibi. As I have had no results, I really dont know why. I have had no follow up from the cardiologist to date.
My concern is why has this last test been ordered? and I habe had chest discomfort at rest and occasional sharp chest pains lasting seconds which come on at rest. My pulse rate is low, between 44 and 60 and blood pressure about 90/50. I was initially prescribed Amlopidine but had to stop taking this as my BP dropped. There are occasions when I feel light headed and dizzy. I am tired most of the time and breathless on exertion, especially after climbing stairs.
Why was I asked if I had spent time in a third world country?
And what is the prognosis and course of aortic schlerosis. Do I have some cardiac ischaemia as well.
This is a bit of a worrying time and I would be grateful if anyone could help with this.
Many Thanks

[CCF HeartMD7]

You seem to have many symptoms and have not had an opportunity to review the the tests that have been ordered to date with either your primary care physician or a cardiologist.  I recommend that you make an appointment with a cardiologist to review the studies that have performed and make recommendations regarding follow-up.  Make sure the cardiologist has access to all of the imaging studies that have been performed.

Aortic sclerosis means calcification or thickening of the aortic valve (the valve that allows blood to flow from the heart to the rest of the body).  It can cause a heart murmur from flow across the thickened valve.  It needs to be monitored (usually once per year) to make sure that the thickening does not progress to a narrowed valve.

Rheumatic fever can cause calcification or thickening - most frequently of the mitral valve but sometimes the aortic valve as well.