Myocarditis; Pericarditis; Could not think; Anxiety related symptoms; Panic attack; Heart palpitations/ Felt rapid powerful palpitations/ Experienced immediately strong palpitations; Chest pain/ Atypical chest pain; Tightness; Along with palpitations and labored breathing; Could not move; Could not walk/ Had to crawl to the bathroom; left lung was closing/ Felt right lung was opening up slowly; Pain; Fatigued; This spontaneous case was reported by a consumer and describes the occurrence of MYOCARDITIS (Myocarditis), PERICARDITIS (Pericarditis) and MENTAL IMPAIRMENT (Could not think) in a 29-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 024C21A and 002C21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included Anxiety.   On 20-Apr-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 17-May-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On an unknown date, the patient experienced MYOCARDITIS (Myocarditis) (seriousness criterion medically significant), PERICARDITIS (Pericarditis) (seriousness criterion medically significant), MENTAL IMPAIRMENT (Could not think) (seriousness criterion medically significant), ANXIETY (Anxiety related symptoms), PANIC ATTACK (Panic attack), PALPITATIONS (Heart palpitations/ Felt rapid powerful palpitations/ Experienced immediately strong palpitations), CHEST PAIN (Chest pain/ Atypical chest pain), CHEST DISCOMFORT (Tightness), DYSPNOEA (Along with palpitations and labored breathing), MOVEMENT DISORDER (Could not move), GAIT DISTURBANCE (Could not walk/ Had to crawl to the bathroom), LUNG DISORDER (left lung was closing/ Felt right lung was opening up slowly), PAIN (Pain) and FATIGUE (Fatigued). At the time of the report, MYOCARDITIS (Myocarditis), PERICARDITIS (Pericarditis), MENTAL IMPAIRMENT (Could not think), ANXIETY (Anxiety related symptoms), PANIC ATTACK (Panic attack), PALPITATIONS (Heart palpitations/ Felt rapid powerful palpitations/ Experienced immediately strong palpitations), CHEST PAIN (Chest pain/ Atypical chest pain), CHEST DISCOMFORT (Tightness), DYSPNOEA (Along with palpitations and labored breathing), MOVEMENT DISORDER (Could not move), GAIT DISTURBANCE (Could not walk/ Had to crawl to the bathroom), LUNG DISORDER (left lung was closing/ Felt right lung was opening up slowly), PAIN (Pain) and FATIGUE (Fatigued) had not resolved.            The patient mentioned that the doctor ordered an echocardiogram and Holter monitor for patient to wear on the chest along with blood tests and waiting for on imaging tests done with doctor. Before taking the appointment of doctor the patient needs to obtain the lab data of Cardiac lab values (Electrocardiogram, cardiac test, cardiac enzymes. No history of COVID-19 infection. Patient stated that his family had a history of high blood pressure in his grandmother and high cholesterol in his dad and also history of knee problems in his family. No concomitant medications was reported. No treatment drug details was reported.  Company comment: This case concerns a 29 year-old, male with a history of anxiety, who experienced the expected events of myocarditis and pericarditis, and the unexepcted event of mental impairement. The events occurred after the second dose of mRNA-1273 Moderna vaccine (exact onset date of events was not recorded).  The event was considered related to the product per the reporter´s assessment. The medical history of anxiety could be a potentially confounder. The benefit-risk relationship of mRNA-1273 Moderna vaccine in not affected by this report.; Sender's Comments: This case concerns a 29 year-old, male with a history of anxiety, who experienced the expected events of myocarditis and pericarditis, and the unexepcted event of mental impairement. The events occurred after the second dose of mRNA-1273 Moderna vaccine (exact onset date of events was not recorded).  The event was considered related to the product per the reporter´s assessment. The medical history of anxiety could be a potentially confounder. The benefit-risk relationship of mRNA-1273 Moderna vaccine in not affected by this report.