Carotid body syndrome with tachycardia; Carotid body syndrome with tachycardia; This spontaneous case was reported by a physician and describes the occurrence of CAROTID ARTERY DISEASE (Carotid body syndrome with tachycardia) in a 5-decade-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 prophylaxis. The occurrence of additional non-serious events is detailed below.     No Medical History information was reported.    On an unknown date, the patient received dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date, the patient experienced CAROTID ARTERY DISEASE (Carotid body syndrome with tachycardia) (seriousness criterion medically significant) and TACHYCARDIA (Carotid body syndrome with tachycardia). At the time of the report, CAROTID ARTERY DISEASE (Carotid body syndrome with tachycardia) and TACHYCARDIA (Carotid body syndrome with tachycardia) had resolved.        For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter did not provide any causality assessments.   Reported that patient in her late 40s (possibly 48 years old). Concomitant medications information was not reported. It was reported that for carotid body syndrome with tachycardia required beta-blocker treatment after moderna vaccine. Reporter was enquiring whether there was a less chance of tachycardia, heart rates in the 150s with the Pfizer vaccine. It was reported that the patient's symptoms went down about 6 months after the dose. It was reported that the Moderna booster was given as half dose.  Company Comment: This is a spontaneous case concerning  a 5 decade old, female patient with no reported medical history, who experienced the unexpected serious (medically significant) event of (AESI) Carotid artery disease and unexpected non-serious event of tachycardia. The exact date of administration of unspecified dose of mRNA-1273 and onset of the events was not specified, hence latency could not be assessed. It was reported that for carotid body syndrome with tachycardia required beta-blocker treatment  No further details on clinical course, lab test results were reported. The events were reported as resolved. The benefit-risk relationship of mRNA-1273 Vaccine, is not affected by this report.    Most recent FOLLOW-UP information incorporated above includes: On 16-Sep-2022: Follow-up received, updated patient identifier, reporter's occupation, Moderna vaccine dose details, product coding and event outcome and narrative.; Sender's Comments: This is a spontaneous case concerning  a 5 decade old, female patient with no reported medical history, who experienced the unexpected serious (medically significant) event of (AESI) Carotid artery disease and unexpected non-serious event of tachycardia. The exact date of administration of unspecified dose of mRNA-1273 and onset of the events was not specified, hence latency could not be assessed. It was reported that for carotid body syndrome with tachycardia required beta-blocker treatment  No further details on clinical course, lab test results were reported. The events were reported as resolved. The benefit-risk relationship of mRNA-1273 Vaccine, is not affected by this report.