Arrhythmia /They measured a 12 second pause 1 time and some other pauses throughout his hospitalization.; fell/smashing his nose and face; He was diagnosed with atrial fibrillation and given a pacemaker on 9AUG2021; Shaking; Sweating; felt cold even with a coat on/stayed in bed for the next 3 days/ couldn't get warm; vision went to nothing; fainting spells/fainting episodes; felt weak like he was going to faint; This spontaneous case was reported by a nurse and describes the occurrence of ARRHYTHMIA (Arrhythmia /They measured a 12 second pause 1 time and some other pauses throughout his hospitalization.), SYNCOPE (fainting spells/fainting episodes) and ATRIAL FIBRILLATION (He was diagnosed with atrial fibrillation and given a pacemaker on 9AUG2021) in an 84-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 031L20A and 039K20A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     The patient's past medical history included Macular degeneration. Concomitant products included LISINOPRIL for Low blood pressure.   On 04-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 01-Feb-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On 01-Feb-2021, the patient experienced TREMOR (Shaking), HYPERHIDROSIS (Sweating), FEELING COLD (felt cold even with a coat on/stayed in bed for the next 3 days/ couldn't get warm) and VISUAL IMPAIRMENT (vision went to nothing). In February 2021, the patient experienced SYNCOPE (fainting spells/fainting episodes) (seriousness criteria medically significant and life threatening) and DIZZINESS (felt weak like he was going to faint). In 2021, the patient experienced ARRHYTHMIA (Arrhythmia /They measured a 12 second pause 1 time and some other pauses throughout his hospitalization.) (seriousness criteria hospitalization, medically significant and life threatening). On 04-Aug-2021, the patient experienced FALL (fell/smashing his nose and face). In August 2021, the patient experienced ATRIAL FIBRILLATION (He was diagnosed with atrial fibrillation and given a pacemaker on 9AUG2021) (seriousness criteria medically significant and life threatening). The patient was treated with LORATADINE (CLARITIN [LORATADINE]) for Adverse event, at an unspecified dose and frequency and Surgery (Given a pacemaker on 09 Aug 2021) for Atrial fibrillation. In February 2021, FEELING COLD (felt cold even with a coat on/stayed in bed for the next 3 days/ couldn't get warm) was resolving. At the time of the report, ARRHYTHMIA (Arrhythmia /They measured a 12 second pause 1 time and some other pauses throughout his hospitalization.), SYNCOPE (fainting spells/fainting episodes), ATRIAL FIBRILLATION (He was diagnosed with atrial fibrillation and given a pacemaker on 9AUG2021), TREMOR (Shaking), HYPERHIDROSIS (Sweating), DIZZINESS (felt weak like he was going to faint), VISUAL IMPAIRMENT (vision went to nothing) and FALL (fell/smashing his nose and face) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Blood pressure measurement: 130/70 (abnormal) His blood pressure is usually 130/70. On an unknown date, Electrocardiogram: abnormal (abnormal) They measured a 12 second pause 1 time and some other pauses throughout his hospitalization.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   Lab test data included ECG, echocardiogram, and imaging but specific results not provided.  He was hospitalized for 1 week with a significant work up of ECG, echocardiogram, and imaging. They measured a 12 second pause 1 time and some other pauses throughout his hospitalization.He was diagnosed with atrial fibrillation and given a pacemaker on 9AUG2021. He has not had any episodes of atrial fibrillation since receiving the pace maker.  Company comment: This case concerns a 84-year-old, male patient with previous relevant medical history of hypertension and use of concomitant medication, who experienced the unexpected events of arrhythmia, syncope and atrial fibrillation. The events occurred approximately 6 months after the second dose of mRNA-1273. The rechallenge was not applicable since the events happened after the second dose. The medical history of hypertension and use of concomitant medication remains a confounder. The benefit-risk relationship of mRNA-1273 is not affected by this report.; Sender's Comments: This case concerns a 84-year-old, male patient with previous relevant medical history of hypertension and use of concomitant medication, who experienced the unexpected events of arrhythmia, syncope and atrial fibrillation. The events occurred approximately 6 months after the second dose of mRNA-1273. The rechallenge was not applicable since the events happened after the second dose. The medical history of hypertension and use of concomitant medication remains a confounder. The benefit-risk relationship of mRNA-1273 is not affected by this report.