Age: 32.0
Sex: M
Vaccine: FLUX
Symptoms: Blood creatine phosphokinase MB increased, Blood creatine phosphokinase increased, Brain natriuretic peptide normal, C-reactive protein normal, Chest discomfort
Clinical narrative: Influenza vaccine induced myocarditis / Atypical acute myocarditis; Midsternal chest pain / The pain as someone sitting on the patient's chest, worsened with lying down and alleviated by leaning forward / The pain awoke the patient from sleep; Reduced exercise tolerance; Exertional shortness of breath / exertional dyspnea; Myalgias; HS-Troponin I was elevated and peaked at 7,453; CPK elevated; CK-MB elevated; PR depressions in leads II, III, aVF, and V4-V6; ST segment elevations in V5 and V6; LDL was elevated at 115; Myocardial enhancement; This literature case was received on 02-Apr-2024 and concerned a 32-year-old, male patient  This conference abstract described a case of influenza vaccine induced myocarditis in a 32-year-old without family history of sudden cardiac death.  The patient did not have any relevant medical history and was not taking any concomitant medications. The patient denied family history of sudden cardiac death; however, the patient's father underwent CABG in his 50s for CAD (coronary artery disease).  On an unspecified date, the patient was vaccinated with influenza vaccine (brand not specified; dose, anatomical location, route of administration, and indication: not reported). The batch number was not reported.  On an unspecified date, one day after receiving influenza vaccine, the patient felt myalgias.  On an unspecified date, two days after receiving influenza vaccine, the patient experienced midsternal chest pain. The patient described the pain as someone sitting on the chest, worsened with lying down and alleviated by leaning forward. The pain lasted ten minutes and awoke the patient from sleep. The patient had reduced exercise tolerance and exertional shortness of breath for a few days. The patient denied recent sick contacts.  On an unspecified date, the patient's high-sensitivity (HS) -Troponin I was elevated and peaked at 7,453 before declining, creatine kinase (CPK) and creatine kinase MB (CK-MB) were both elevated, brain natriuretic peptide (BNP), erythrocyte sedimentation rate (ESR) and c-reactive protein (CRP) were within normal limits, low-density lipoprotein (LDL) was elevated at 115, viral respiratory panel was negative, electrocardiogram (EKG) demonstrated PR depressions in leads II, III, aVF, and V4-V6 with ST segment elevations in V5 and V6, echocardiogram showed no abnormalities, and cardiac magnetic resonance imaging (MRI) demonstrated mid myocardial enhancement and fibrosis of the anteroseptal wall from mid cavity extending to apex, consistent with myocarditis. The patient received aspirin at a dose of 650 mg, every eight hours, and colchicine at a dose of 0.6 mg, twice daily.   On an unspecified date, the patient was discharged with outpatient follow up and advised to avoid strenuous activity.  The outcome of the event 'Acute myocarditis' was not reported.  Reporter's assessment: The reporter assessed the event of 'acute myocarditis' as related to influenza vaccine.   In conclusion, influenza vaccine induced myocarditis was a rare clinical scenario which should be included in the differential when young, healthy patients present with chest pain and exertional dyspnea.   The event of 'acute myocarditis' was considered to be medically significant by a Physician within Seqirus's Regulatory Department.  Reporter's Comments: Listedness: Unlisted. Causality: Considering close proximity of onset of first symptoms, and taking into account the laboratory findings provided causal role of the suspect vaccine could not be ruled out. Additionally applied treatment speaks in support of an autoimmune rather then infective aetiology. With the curently available information causality for the event myocarditis is assessed as possibly related.