pericarditis; Something with his vagus nerve; coxsackie viral infection; chest pain for weeks/grabbing his left breast bone; inflammation; shortness of breath; felt he was going to pass out; shoulder pain; This spontaneous case was reported by a consumer and describes the occurrence of PERICARDITIS (pericarditis) in a 27-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     The patient's past medical history included COVID-19 in December 2020, Heart rate irregular (irregular heart beat with pauses for a few seconds at a time with a pacemaker) and Pacemaker insertion (cardiac).   On 30-Apr-2021, the patient received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On an unknown date, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On an unknown date, the patient experienced PERICARDITIS (pericarditis) (seriousness criterion medically significant), VAGUS NERVE DISORDER (Something with his vagus nerve), COXSACKIE VIRAL INFECTION (coxsackie viral infection), CHEST PAIN (chest pain for weeks/grabbing his left breast bone), INFLAMMATION (inflammation), DYSPNOEA (shortness of breath), DIZZINESS (felt he was going to pass out) and ARTHRALGIA (shoulder pain). The patient was treated with INDOMETACIN SODIUM (INDOMETHACIN [INDOMETACIN SODIUM]) for Pain, at an unspecified dose and frequency and COLCHICINE for Inflammation, at an unspecified dose and frequency. At the time of the report, PERICARDITIS (pericarditis), VAGUS NERVE DISORDER (Something with his vagus nerve), COXSACKIE VIRAL INFECTION (coxsackie viral infection), CHEST PAIN (chest pain for weeks/grabbing his left breast bone), INFLAMMATION (inflammation), DYSPNOEA (shortness of breath), DIZZINESS (felt he was going to pass out) and ARTHRALGIA (shoulder pain) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Blood test: coxsackie viral infection (abnormal) showed evidence of a coxsackie viral infection. On an unknown date, Echocardiogram: 50-55%. (abnormal) Echo showed pericarditis, and an ejection fraction of 50-55%. and 35-40% (abnormal) showed an ejection fraction of 35-40%.. On an unknown date, Ejection fraction: 50-55%. (abnormal) ejection fraction of 50-55% and 35-40% (abnormal) showed an ejection fraction of 35-40%..         No concomitant drug information provided. In the past 6 weeks patient had developed pericarditis. Patient was attributing the pain initially to work, as patient works at a factory. Patient also had instance when got out of a shower, felt of going to pass out, and laid down but did not pass out. Company comment This case concerns a 27-year-old male patient, with medical history of Heart rate irregular and coxsackie viral infection, who experienced the expected serious event of Pericarditis (AESI). The event occurred after the administration of the second dose of mRNA-1273 vaccine. Patient´s medical history of Heart rate irregular and coxsackie viral infection, remains as confounders. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report. Sender's Comments: This case concerns a 27-year-old male patient, with medical history of Heart rate irregular and coxsackie viral infection, who experienced the expected serious event of Pericarditis (AESI). The event occurred after the administration of the second dose of mRNA-1273 vaccine. Patient´s medical history of Heart rate irregular and coxsackie viral infection, remains as confounders. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report.