Chest pains

I am a 49 year old female that has been having chest pains intermittently for 3 months now.  They are in the upper part of the chest and in the center.  They radiate to the underneath side of the left arm....feels like a blood pressure cuff is on the arm.  Occasionally the pain will make me feel like I have a tight collar around my neck...making it difficult to breathe.  I am not short of breath but do get a little diaphoretic.  I am 30 lbs over weight, a smoker, strong family history of cardiac problems, and a high cholestrol of 233.  I additionally have systemic lupus.
I have been to a cardiologist for a cardiolyte stress test that showed minimally significant with a .5 ST depression.  The thing that concerned the cardiologist was that my blood pressure went up to 245/138 and stayed there.  My heart rate was obtained at 145 with some modifications of the grade of the treadmill.  I had asked them to stop due to the chest heaviness, leg weak, and the shortness of breath...they wouldn't do it.  The cardiologist said that the thing that would be recommended next would be a caridac catheterization if the chest pains continue.  My questions are this:
1.  What is the percentage of accuracy of the cardiolyte stress test for females?  
2.  Could these chest pains be lupus related?  
3.  Should a catheter be done based upon the symptoms and history?  (even with a minimally significant test)
4.  What other medications could I take that would help the chest pain besides nitro?  Current medications are lasix 160 mg daily, plaquenil 400 mg daily, and synthroid .075mg.  

Thanks for your help in answering these questions.

[Cleveland Clinic, MD]

Dear Becky,

1. What is the percentage of accuracy of the cardiolyte stress test for females?
A: A cardiolyte test has about a 90% accuracy rate in women.

2. Could these chest pains be lupus related?
A: Yes, chest pains can sometimes be lupus related.

3. Should a catheter be done based upon the symptoms and history? (even with a minimally significant test)
A: If the pains continue I too would probably recommend a catheter test.

4. What other medications could I take that would help the chest pain besides nitro? Current medications are lasix 160 mg daily, plaquenil 400 mg daily, and synthroid .075mg.
A: The first thing is to establish an accurate diagnosis and then  the proper medicines can be given.

[Mary, Pls. answer. Unable to ever log on]

Is a Cardiolyte Stress Test the same as a Thallium Stress test?

Is ending a Thallium Stress test with a BP of 245/60 cause for alarm and immediatley coming down to 130/60 a few minutes later?

Thank You.