Family history - After receiving my (mother) second covid vaccine (Pfizer) I had an immediate reaction (at 4 minutes). My symptoms included extreme tachycardia, elevated BP, presyncope, and extreme temperature changes (sweating then freezing). This lasted several hours before it started to fade. Three weeks later the same symptoms came back, but this time with the vengeance. I ended up in the emergency room twice, due to tachycardia and inability to stand without my heart rate skyrocketing. I was also having recurrent episodes of presyncope as well as extreme temperature changes and brain fog. All would come in an episode and then pass -which would leave me exhausted, but as time went on they became more severe and more frequent. I wore a 30-day holter monitor and was put on a heavy dose of beta blocker. Since then my symptoms have slowly decreased, but I will still have occasional episodes with the same above symptoms. I am still on a beta blocker and am being followed.  My husband received Moderna, and had no adverse reactions.  Because of my reaction, we were on edge regarding patient. In his past he has had 3 ?episodes? - 2 episodes of presyncope (once in the fourth grade and once in the fifth grade) and 1 episode of syncope (once in the sixth grade). These were not frequent occurrences at all, but because of my history his pediatrician wanted to have him checked out by the syncope clinic prior to dose #2 and so that we had a contact in case he did have an adverse reaction like I did.  He was checked out by syncope clinic, all clear, and he received his second dose that same day on August 11th. He had no adverse reaction initially. But on August 14th he had an extreme episode of presyncope while he was at a friend's house playing outside. It happened several times in a row and he called to be picked up (not like him while at a friend's house). Since then these episodes are increasing in frequency as the weeks pass. And they are also increasing in severity - as the last few he has had brain fog and been disoriented (he walked out of school thinking it was the last bell before a friend reoriented him). He has been complaining of heart flutters and he feels like his heart is racing during them. The last episode he became extremely hot. These can happen when sitting in class, when running around with friends, or merely walking. After a cross country meet he told me he had the worst cramp ever during the race. I asked him where his cramp was and he pointed to his chest/sternum area. (This concerned us, given my typical running cramps are on my side) My husband took a video of him during his meet (to cheer him on, not for this purpose) but when viewing it last night we noticed he was grabbing his chest while running.He also said he had a heart flutter again during the race. For weeks we kept the syncope clinic informed of his new and increasing symptoms. A stress test was ordered (and all looked okay), but his symptoms continued to increase in frequency and severity after this test. His symptoms have persisted until this date of filling out this report. We had an appointment with cardiology, where did not do an echo (despite the above symptoms and not having one post vaccine number 2 ? when his symptoms began). But he is currently wearing a 14 day heart monitor.