atrial fibrillation; kidneys are working at 50%; diverticulitis (not clear if happened after or before the shots); respiratory problems; stomach problems; felt really lethargic; no energy; I felt like I had the flu / like patient caught the flu and overall kind of sickness; This spontaneous case was reported by a consumer and describes the occurrence of ATRIAL FIBRILLATION (atrial fibrillation) in a 72-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 012A21A and 007M20A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concomitant products included BIFIDOBACTERIUM LACTIS (PROBIOTIC [BIFIDOBACTERIUM LACTIS]) for Stomach pain, APIXABAN (ELIQUIS), LOSARTAN POTASSIUM (COZAAR), ALFUZOSIN HYDROCHLORIDE (UROXATRAL), LANSOPRAZOLE (PREVACID), COLECALCIFEROL (VITAMIN D3), BUDESONIDE, FORMOTEROL FUMARATE (SYMBICORT), IPRATROPIUM BROMIDE, SALBUTAMOL SULFATE (COMBIVENT) and BUDESONIDE (ENTOCORT) for an unknown indication.   On 12-Feb-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 08-Mar-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. In March 2021, the patient experienced INFLUENZA LIKE ILLNESS (I felt like I had the flu / like patient caught the flu and overall kind of sickness), LETHARGY (felt really lethargic) and ASTHENIA (no energy). In April 2021, the patient experienced ATRIAL FIBRILLATION (atrial fibrillation) (seriousness criterion medically significant), RENAL IMPAIRMENT (kidneys are working at 50%), DIVERTICULITIS (diverticulitis (not clear if happened after or before the shots)), RESPIRATORY DISORDER (respiratory problems) and ABDOMINAL DISCOMFORT (stomach problems). The patient was treated with PARACETAMOL (TYLENOL) at a dose of 1 dosage form; IBUPROFEN (MOTRIN [IBUPROFEN]) at a dose of 1 dosage form and Surgery (Patient had heart ablation) for Atrial fibrillation. At the time of the report, ATRIAL FIBRILLATION (atrial fibrillation), RENAL IMPAIRMENT (kidneys are working at 50%), DIVERTICULITIS (diverticulitis (not clear if happened after or before the shots)), RESPIRATORY DISORDER (respiratory problems), INFLUENZA LIKE ILLNESS (I felt like I had the flu / like patient caught the flu and overall kind of sickness) and ABDOMINAL DISCOMFORT (stomach problems) outcome was unknown and LETHARGY (felt really lethargic) and ASTHENIA (no energy) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): In March 2021, Heart rate: irregular heartbeat (abnormal) irregular heartbeat.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   This case concerns a 72-year-old male patient with no details on previous relevant medical history, who experienced the unexpected serious event of Atrial fibrillation with other non serious events after Spikevax (mRNA- 1273 vaccine / Moderna COVID-19 Vaccine). The onset of the event occurred approximately 1 month after the second dose of Spikevax. Cardiac ablation was performed. The rechallenge is not applicable, since the event was reported exclusively after the second dose. Patient´s age remains a confounder. The benefit-risk relationship of Spikevax vaccine is not affected by this report. Diverticulitis and Renal impairment were automatically upgraded as serious as per IME list. However, based on information available and due to the lack of evidence of seriousness from a regulatory or clinical standpoint, they were assessed as non-serious.; Sender's Comments: This case concerns a 72-year-old male patient with no details on previous relevant medical history, who experienced the unexpected serious event of Atrial fibrillation with other non serious events after Spikevax (mRNA- 1273 vaccine / Moderna COVID-19 Vaccine). The onset of the event occurred approximately 1 month after the second dose of Spikevax. Cardiac ablation was performed. The rechallenge is not applicable, since the event was reported exclusively after the second dose. Patient´s age remains a confounder. The benefit-risk relationship of Spikevax vaccine is not affected by this report. Diverticulitis and Renal impairment were automatically upgraded as serious as per IME list. However, based on information available and due to the lack of evidence of seriousness from a regulatory or clinical standpoint, they were assessed as non-serious.