Strange reading for B/P during Stress test, normal flunctuations?

HI , I had my Stress test on April 28th, via Persantine, because I can not use the usual tread mill because of my back and a bad foot. Because of the results which were abnormal, I am set for a cardiac catherization this MOnday, June 2'nd. The question I have though is regarding the flunctuations in blood pressure reading during rest and stress.

       My Resting Blood pressure at the start was 136/68 pulse 54.

During the stress part, the blood pressure over a four minute timeframe had the following readings:
  1 minute. 132/66 pulse 47
  2 minute : 120/87 pulse 60
  3 Minute: 138/65 pulse 62
   4 Minute: 120/61 pulse 69
Persantine in, tingling in chest, not pain but hot and tingling feeling.
5 Minute:  126/65 Pulse 79
6 Minute   132/62 Pulse 94
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Isotope. ( Cardiac Dye for Gamma Camera taking pictures of at rest and Stress )
Injection time; 132/62 Pulse 93
1 Minute:    128/48 Pulse 88
2 Minutes:  130/56 Pulse 86
3 Minutes:  129/55 Pulse 88

To me these numbers seem to have such a difference betweent he Systolic and Dystolic, esp the 1 minute reading of 128/48, that is a difference of 80 pts!!! Is that normal such a difference? Also why is my pulse as high as when at stress, just resting with dye injected?  If my resting heart rate started out as 54 and as high as I got under the medication stress at 6 minutes was 94, is that a high enough heart rate to get accuarte results.??

I noticed the big change in my blood pressure was not the Systolic, ( top number) but the dystolic, there was a big difference .

Anyone have any experiences iin blood pressure readings like this or understanding the change in readings? Thanks in advance for any help.                                                                 Fluffypurrcat