Various Cardiac Abnormalities Caused by Bacterial Myocarditis

Abstract

SummaryA 69-year-old woman without any past disease history was hospitalized for heart failure. After hospitalization, she showed myocardial infarction, atrioventricular dissociation, and cardiac dysfunction, and finally she passed away despite intensive care. Autopsy revealed that the cardiac abnormalities were due to bacterial myocarditis possibly resulting from urinary tract infection by E. coli. Although bacterial myocarditis is rare in developed countries, we should consider its possibility when patients show various cardiac abnormalities with bacterial infection.(Int Heart J 2018; 59: 229-232) Key words: Heart failure, Myocardial infarction, Atrioventricular dissociation M yocarditis induces various cardiac abnormalities including systolic dysfunction and arrhythmia. The most common cause of myocarditis in developed countries is the infection of viruses such as coxsackievirus, adenovirus, enterovirus, parvovirus B-19, parainfluenza viruses and human herpesvirus-6. 1,2) Although bacterial myocarditis was has been very rare in developed countries, 3) the number of patients with bacterial myocarditis has recently been increasing because of an increase in immunocompromised hosts. In most cases, bacterial myocarditis is suspected based on clinical test results, but few cases have been diagnosed while alive. We here present a patient who suddenly developed myocardial infarction, atrioventricular dissociation, and heart failure without any past disease history. Morbid anatomy revealed that the diagnosis was bacterial myocarditis. Here we describe the various clinical and pathological findings of this case and with some also discussions about bacterial myocarditis in general. Case ReportA 69-year-old woman visited our hospital because of death of her brother's death. While she was plunged in grief, she suddenly felt dyspnea. Approximately 2 weeks before, she had visited a local doctor because of wheezing and insomnia. Pleural effusion had been found by chest X-ray examination, and a diuretic had been prescribed. In our hospital, she had slight tachycardia (106/minute) but other physical findings, including blood pressure (118/64 mmHg) and body temperature (35.5 ), were normal (35.5 ). X-ray examination revealed bilateral pleural effusion and pulmonary congestion, and the electrocardiogram showed a negative T wave in I, aVL, and V3-6 leads. Routine blood examination revealed the elevation of C-reactive protein levels (4.8 mg 8 mg/dL) and white blood cell counts (13.9 × 10 3 /μL). Ultrasound echocardiography showed dilatation of the left ventricle (left ventricular dimension diastolic/systolic 60/51 mm), systolic dysfunction (ejection fraction 31%), mild aortic regurgitation, and moderate mitral regurgitation. The wall motion was diffusely reduced, and in particular, the wall motions of the inferior apex wall and the anterolateral wall were severely impaired. We diagnosed her as acute decompensated heart failure with unknown etiology and administered furosemide, carperitide and dobutamine. Since she had no fever a...

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