Harley444444

I don't know where to begin....In Sept. I found out that I was passing out without any warnings what so ever....I was finally put on a monitor, where the hospital finally found out that my heart stopped for 7 seconds and finally took off again.  I ended up with a pacemaker...I had nothing else really wrong with me, blood pressure, colest. etc. normal.  However, I have had cancer 3 times, breast cancer twice, and ov. this last time..I ended up doing radation for the 2nd bout of breast cancer.
There were thoughts that radation might have made the heart problem.
The biggest problem I have now is....I can just be sitting down, doing nothing and this weird feeling comes over me, a lot of times this happens at resturants, I get the chills, then hot, I zone out, it will last up to  10 minutes, then usually I am fine.  I ended up in the er about 3 weeks ago, they gave me 3 hits of nitro, and couldn't find anything....it did bring the blood pressure down to normal...Yesterday, the weird feeling hit again, it's beginning to scare me.  I go to my doctors more then regular....I am on top of everything.  They just can't find out what this is...Can you help me?Thanks
Harley