A-Fib; cardiologist saw it on the computer, an arrhythmia; hard poundings that were very bad, clarifies like fist continually pounding in her chest; feeling something strange, like a flurry by the heart; This is a spontaneous report from a contactable consumer (patient). An 83-year-old female patient received BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE; Solution for injection; Lot Number: EN6198, Expiration Date: Not reported) via an unspecified route of administration on arm on 19Feb2021 13:30 at single dose for COVID-19 immunization. The patient's medical history included ongoing bronchiectasis (At least a year but not sure). Concomitant medication included ongoing tiotropium bromide (SPIRIVA; 18 ug, capsule) via nasal route at 18 ug, once a day (inhalation/At least a year but not sure) for bronchiectasis. It was reported that, the patient had her first vaccine on 19Feb2021. On 20Feb2021, she started feeling something strange, clarifies like a flurry by her heart, she doesn't know what really. She states that on 21Feb2021 and 22Feb2021 she had hard poundings that were very bad, clarifies like fist continually pounding in her chest. On 23Feb2021, she saw the cardiologist and he put her in the hospital. She states that it was probably a reaction from the vaccine, it was A-Fib. It was probably a reaction, but nobody can say, she was 83 but healthy, no diabetes, high blood pressure or anything except one little thing. Today was the date for the second dose, and she was reluctant to get it. Caller clarifies that the pounding subsided on 21Feb2021 and started again on 22Feb2021 and on 23Feb2021 she went to the cardiologist. Treatment included Aleve hard poundings that were very bad, clarifies like fist continually pounding in her chest AE: clarifies that it was going for quite a while, it was undeniable on 21Feb2021. States on 22Feb2021, it lasted a few minutes. feeling something strange, like a flurry by the heart AE: states that it was there for a minute. A-Fib: states that the cardiologist saw it on the computer, an arrhythmia. States they saw it at the doctor's office on the computer, she didn't feel it on 23Feb2021. States it is unknown if it started on 21Feb2021, 22Feb2021, 23Feb2021. States she doesn't know when it ended, she was put in the hospital. States she didn't feel it to know so she couldn't identify it, but it showed on the computer. Treatment with Aleve, but no other treatment, she was afraid to take anything. Hospitalization: Caller states that she went to the cardiologist on 23Feb2021 and states he saw on the computer the AFIB and admitted her. Clarifies that he sent her to the emergency room and then she was put upstairs into a room and may have been admitted when she went upstairs, she was there for a couple of days. She states that they didn't have a room at the time, they had lots of people with Covid. States she was admitted on 23Feb2021. She states she was released on she believes the 26Feb2021 but could be 26Feb2021 or 28Feb2021 but believes 26Feb2021. States the was put on medications to monitor to see what would coincide with each other, she is not sure. Patient was started on the following medications during her hospitalization and prescribed them. Metoprolol 25mg once a day by mouth, started when admitted to the hospital. Dofetilide 250mg capsule twice a day by mouth, started after admission to hospital. Blood thinner called Eliquis 2.5mg twice a day by mouth, started during hospitalization. Clarifies that she was not on these medications before the vaccine, she started them when she was at the hospital and takes them now. States she was one medication, but she stopped taking it right away and it has nothing to do with this. For event A-Fib, which results in Emergency Room visit and Physician Office visit. The seriousness of the events was reported as hospitalization. The event Feeling abnormal was recovered on 20Feb2021, Chest discomfort was recovered on 22Feb2021, Arrhythmia was recovered on an unspecified date in 2021, whereas unknown for another event.