heart pounding; this is a spontaneous report received from a contactable consumer from the ra. regulatory number: gb-mhra-webcovid-202202181219517070-jzrsz. other case identifier(s): gb-mhra-adr 26619885. a 21 year-old female patient received bnt162b2 (comirnaty), administration date 15dec2021 (lot number: fk9712) at the age of 21 years as dose 1, single for covid-19 immunisation. the patient's relevant medical history and concomitant medications were not reported. the following information was reported: palpitations (medically significant) with onset 15dec2021, outcome "not recovered", described as "heart pounding". the patient underwent the following laboratory tests and procedures: sars-cov-2 test: negative. additional information: the patient has not tested positive for covid-19 since having the vaccine. the patient is not enrolled in clinical trial and has not had symptoms associated with covid-19. no follow-up attempts are possible. no further information is expected.; sender's comments: linked report(s) : gb-pfizer inc-202200319469 same patient and reporter; different vaccine dose and event