Thanks for responding, zip! I have heard that changing positions can also change heart rate, such as standing up too quickly, so maybe it can also happen shooting a basketball and throwing your arms up quickly. I don't understand why they say it's just a coincidence. I go back to the cardiologist at the end of May. I'll update then. I'm still very insterested in anything anyone has to say about this, so please continue posting! Thanks so much.
-Kel