A Case of Myocardial Biopsy in Fulminant Myocarditis

Abstract

Clinical Data A 25-year-old female patient was admitted to our hospital on September 4, 2019, with “fever for 3 days and chest tightness and shortness of breath for 2 days”. She had no previous history of coronary heart disease or hypertension. Three days before admission, she developed chills, low-grade fever, dry cough, and clear nasal discharge after catching a cold. Two days before admission, she experienced chest tightness and shortness of breath after mild physical activity, which relieved after rest. Admission physical examination: Temperature 37.3 ℃, blood pressure 85/55 mmHg, clear consciousness, poor mental state, pale complexion, respiratory rate 27 breaths/min, heart rate 108 beats/min, regular rhythm, no murmurs. Abdomen (-), no edema of lower extremities. Admission ECG: Sinus rhythm; ST segment elevation of 0.1–0.3 mv in leads II, III, aVF, V1-V6, and pathological Q waves in leads II, III, aVF. Initial diagnosis after admission: Fulminant myocarditis? Acute ST-segment elevation myocardial infarction (to be excluded). Laboratory tests on admission: D-dimer: 0.45 mg/L, B-type natriuretic peptide (BNP): 7401.8 pg/mL, high-sensitivity troponin I (cTnI): 11.41 ng/mL; creatine kinase isoenzyme (CK-MB): 59.2 ng/mL, myoglobin: 132.5 ng/mL; total white blood cell count: 3.74 × 10⁹/L; hemoglobin: 125 g/L, C-reactive protein (CRP): 19 mg/L, erythrocyte sedimentation rate (ESR): 24 mm/1 h, procalcitonin: 0.07 ng/mL. Blood gas analysis (without oxygen inhalation): pH value: 7.403; partial pressure of carbon dioxide: 31.60 mmHg; partial pressure of oxygen: 45.50 mmHg; blood oxygen saturation: 79.00%; blood lactic acid (lac): 2.3 mmol/L. Transthoracic echocardiography showed: Left atrial diameter 31 mm, left ventricular diameter 35 mm, right atrial diameter 31 mm, right ventricular diameter 23 mm, interventricular septum 13 mm, left ventricular ejection fraction (LVEF) 60%. Chest CT plain scan: No exudative lesions in both lungs. Coronary CTA: No coronary artery stenosis. Cardiac magnetic resonance imaging (MRI): Normal diameters of each cardiac chamber, normal left ventricular function, no definite myocardial fibrosis or edema.