a fib for 8 hours.; Got sick immediately; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP).  A 50-year-old male patient received BNT162b2, BNT162b2 omi ba.4-5 (BNT162B2, BNT162B2 OMI BA.4-5), as dose 3 (booster), single (Batch/Lot number: unknown) for covid-19 immunisation. The patient had no relevant medical history. There were no concomitant medications. Vaccination history included: Covid-19 vaccine (DOSE 1; MANUFACTURER UNKNOWN), for COVID-19 immunization; Covid-19 vaccine (DOSE 2; MANUFACTURER UNKNOWN), for COVID-19 immunization. The following information was reported: ATRIAL FIBRILLATION (medically significant), outcome "unknown", described as "a fib for 8 hours."; ILLNESS (non-serious), outcome "unknown", described as "Got sick immediately". The events "a fib for 8 hours." and "got sick immediately" required physician office visit and emergency room visit. The patient underwent the following laboratory tests and procedures: Weight: probably 210 or 220. Therapeutic measures were taken as a result of atrial fibrillation, illness. Additional information: Calling because Pfizer needs to certainly add heart problems connected to COVID shot. Had her son in law who needed cold ablation due to the COVID shot and the cardiologist will say it was from the COVID shot. Her son in law had no problems until first COVID booster and then was in a fib for 8 hours. Her son in law had the two shots and then he had the booster at what the HCP determined to be the appropriate time space. He started getting sick almost immediately after the shot, went home, and had his son take him to the hospital. Hospital wouldn't say anything but the cardiologist said it was connected to the COVID Booster. Her son in law had never had a heart problem and it is too close to the shot. Hospital got it back in order, seemed to do ok, and then it went out again. Hospital did one heart shock which only lasted 5 hours. HCP thought it was because he hadn't been on a medicine long enough. Did a shock again and it lasted but he had to see the next level cardiologist. That cardiologist said her son in law was the 6th person being treated for the same situation. Other patient information unknown for other patients being treated for same situation. Cardiologist said her son in law was too young to stay on medicine and did a cold ablation in December and so far it has been good. None of her daughters family will take another one. Her daughter's oldest son had reactions to both the COVID shots. He had temperature, lethargic, and didn't eat. Is sure with his father he will never get another one either. Daughter's oldest son would have been 11 or 12 at the time. It was known that boys were having heart issues at that age. Got sick immediately: Happened maybe a year ago. Her son in law got the booster and the issues started then started again this fall. Clarified she doesn't remember when he got it. May have been this summer and then the second issue cropped up this fall. All she knows it is took 8 hours in the emergency room for the HCP to get it back in control. Clarified he was only in the emergency room and was not admitted to the hospital. Basically, her son in law got sick right after the shot, didn't connect it until he got home, called his son when things were not right. Cold Ablation: The second cardiologist said her son in law was too young to be on mediations and needed a cold ablation to make sure it stays. When having a cold ablation, a person is put into A fib to fix it so the HCP knows it is fixed. It was a quick progression. Happened in Dec2022, mid-December maybe the 14th. Thinks her son in law has recovered as far as she knows. Follows up with the cardiologist and things. Feels like he is ok. Dose: Knows since her son in law is a larger man the dose is based on height and weight. Seems to be a lot of young people dropping dead that are athletes. Has seen the information by morticians that don't want to be named, seen blood clots, and has tried to do as much research as she could. The difference between reading the actual reports verses what Pfizer puts out there is a disconnect. Like finding out that mice blood was used in vaccinations and how the information has gone from mice RNA into human DNA and the problems with that that people don't want to admit. Just finished reading a book by national cancer institute doctor who will tell the truth. She is a citizen and tries to read, follow rules, and expects integrity from everyone else. This was scary and luckily her husband and her did not get COVID because she was careful. Both her and her husband are on Vitamin D 5000mg every day which is why she didn't get COVID. She is on Vitamin D because of cancer and CLL and had her antibodies tested after first two shots and didn't have any antibodies. She took the booster and still probably didn't have any antibodies.   No follow-up attempts are possible; information about lot/batch number cannot be obtained. No further information is expected.