A-Fib/ ablation; This spontaneous case was reported by a patient and describes the occurrence of ATRIAL FIBRILLATION (A-Fib/ ablation) in a 72-year-old male patient who received mRNA-1273 BIVALENT .222 (MODERNA COVID-19 VACCINE, BIVALENT (ORIGINAL AND OMICRON BA.4/BA.5)) (batch no. AS7140C) for COVID-19 prophylaxis.     The patient's past medical history included Atrial fibrillation (A-Fib since 2019 and it was resolved in 2019 with Balloon) in 2019 and Cardiac ablation on 03-Apr-2023. Concurrent medical conditions included Glaucoma (Glaucoma for 10 years) and Diabetic (Diabetic since 42 years old,). Concomitant products included SAMBUCUS NIGRA FRUIT (ELDERBERRY [SAMBUCUS NIGRA FRUIT]), VITAMIN C [ASCORBIC ACID], ATORVASTATIN, VITAMIN D3, ENALAPRIL, GLYBURIDE, SITAGLIPTIN PHOSPHATE (JANUVIA), LATANOPROST, MELATONIN, METFORMIN HYDROCHLORIDE (METFORMIN ARCANA), TIMOLOL, HYDROCHLOROTHIAZIDE, TRIAMTERENE (TRIAMTERENE & HCTZ), WARFARIN and ZINC for an unknown indication.    On 08-Sep-2022, the patient received fifth dose of mRNA-1273 BIVALENT .222 (MODERNA COVID-19 VACCINE, BIVALENT (ORIGINAL AND OMICRON BA.4/BA.5)) (unknown route) 1 dosage form. On an unknown date, the patient experienced ATRIAL FIBRILLATION (A-Fib/ ablation) (seriousness criterion medically significant). The patient was treated with DILTIAZEM in 2022 at a dose of 120 milligram twice a day and OMEPRAZOLE MAGNESIUM (PRILOSEC [OMEPRAZOLE MAGNESIUM]) in April 2023 at a dose of daily for 30 days. At the time of the report, ATRIAL FIBRILLATION (A-Fib/ ablation) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 10-Feb-2021, Electrocardiogram: showed A-Fib.     For mRNA-1273 BIVALENT .222 (MODERNA COVID-19 VACCINE, BIVALENT (ORIGINAL AND OMICRON BA.4/BA.5)) (Unknown), the reporter did not provide any causality assessments.   Patient had received dose 1, first primary monovalent dose on 8-Feb-2021, Lot number 031M20A and dose 2, 2nd primary monovalent dose on 16-Mar-2021, Lot 048A21A and dose 3, first monovalent booster dose on 29-Oct-2021, Lot 053E21A and dose 4, 2nd monovalent booster dose on 8-Apr-2022, Lot 065K21A. Expiration dates for all doses were unknown.   It was stated that the next day after the first primary shot on 9-Feb-2021, patient did an apple watch EKG and it showed A-Fib and it lasted for 2 weeks. Patient did not had any symptoms. After the 2nd shot, on 16-Mar-2021, patient was on A-Fib again and it continued and it did not stopped and still did not had symptoms.   Patient stated that his doctor finally decided to have oblation done on 3-April-2023 and patient had an Echocardiogram done on 11-Apr-2023. In 2021 the doctor prescribed Diltiazem ER 120 mg once a day for his A-Fib after vaccination. He was not able to see the doctor for another year. In 2022, The doctor increased Diltiazem ER 120 mg to two capsules a day.  It was reported that after oblation on 3-Apr-2023 the doctor prescribed Prilosec daily for 30 days. Patient did not take it all the time and stated that the doctor told him to get a 6th shot.  Company comment: This is a spontaneous case regarding a 72-year-old male patient, with medical history of atrial fibrillation resolved in 2019 with Balloon and concurrent medical condition of diabetes and under treatment with timolol, who experienced the serious (due to medically significant), unexpected event of atrial fibrillation (AESI) which occurred on an unknown date after receiving mRNA-1273.222 (Original/Omicron BA.4/BA.5) vaccine, received as the fifth dose of COVID-19 vaccination schedule. Patient received 5 doses of Moderna COVID-19 vaccine; the next day after the first primary dose, patient did an apple watch EKG and it showed A-Fib that lasted 2 weeks. He did not have any symptoms; doctor prescribed Diltiazem ER 120 mg once a day. Approximately 1 year later, doctor increased Diltiazem ER 120 mg to two capsules a day. Patient stated that, after the second vaccination, he was on asymptomatic A-Fib again and it continued. His doctor decided to perform ablation approximately 7 months after 5th dose and prescribed Prilosec daily for 30 days. It was reported that Echocardiogram was done, however results were not disclosed. Medical history of atrial fibrillation, concurrent medical condition of diabetes and concomitant product timolol remain as confounding factors. The benefit-risk relationship of mRNA-1273.222 (Original/Omicron BA.4/BA.5) vaccine is not affected by this report.   This case was linked to US-MODERNATX, INC.-MOD-2023-719402, US-MODERNATX, INC.-MOD-2023-719403 (Linked Report). This case was linked to MOD-2023-719297 (Patient Link).   Most recent FOLLOW-UP information incorporated above includes: On 12-Apr-2023: Live follow up received contains non significant information.; Sender's Comments: This is a spontaneous case regarding a 72-year-old male patient, with medical history of atrial fibrillation resolved in 2019 with Balloon and concurrent medical condition of diabetes and under treatment with timolol, who experienced the serious (due to medically significant), unexpected event of atrial fibrillation (AESI) which occurred on an unknown date after receiving mRNA-1273.222 (Original/Omicron BA.4/BA.5) vaccine, received as the fifth dose of COVID-19 vaccination schedule. Patient received 5 doses of Moderna COVID-19 vaccine; the next day after the first primary dose, patient did an apple watch EKG and it showed A-Fib that lasted 2 weeks. He did not have any symptoms; doctor prescribed Diltiazem ER 120 mg once a day. Approximately 1 year later, doctor increased Diltiazem ER 120 mg to two capsules a day. Patient stated that, after the second vaccination, he was on asymptomatic A-Fib again and it continued. His doctor decided to perform ablation approximately 7 months after 5th dose and prescribed Prilosec daily for 30 days. It was reported that Echocardiogram was done, however results were not disclosed. Medical history of atrial fibrillation, concurrent medical condition of diabetes and concomitant product timolol remain as confounding factors. The benefit-risk relationship of mRNA-1273.222 (Original/Omicron BA.4/BA.5) vaccine is not affected by this report. US-MODERNATX, INC.-MOD-2023-719402:This case is for Doctor 1 out  of 2 doctors US-MODERNATX, INC.-MOD-2023-719403:This case is for Doctor 2 out  of 2 doctors