Probable brucellosis-associated myocarditis presenting as myocardial infarction with non-obstructive coronary arteries: a case report

ABSTRACT Background Brucellosis remains an important zoonotic disease in endemic regions and has heterogeneous clinical presentations. Cardiovascular involvement is uncommon, with myocarditis representing a rare but potentially serious manifestation. Brucellosis-associated myocarditis may mimic acute coronary syndrome (ACS), creating diagnostic uncertainty when obstructive coronary artery disease is absent. Case Summary We report a case of probable brucellosis-associated myocarditis in a 27-year-old previously healthy man with recently diagnosed brucellosis who developed acute chest pain and dyspnea accompanied by ischemic electrocardiographic changes and marked troponin elevation. Transthoracic echocardiography showed preserved biventricular systolic function without regional wall-motion abnormalities, significant valvular disease, or pericardial effusion. Coronary angiography demonstrated normal coronary arteries without obstructive disease, establishing a working diagnosis of myocardial infarction with non-obstructive coronary arteries (MINOCA). In the absence of cardiac magnetic resonance imaging (MRI) or endomyocardial biopsy, the suspected myocarditis etiology was supported by the temporal relationship with active brucellosis, dynamic biomarkers, and electrocardiographic changes, exclusion of obstructive coronary artery disease, and subsequent clinical recovery. Because antimicrobial and anti-inflammatory therapies were administered concurrently, the response cannot be attributed to either intervention alone. No relapse or recurrent cardiac symptoms occurred during six months of follow-up. Conclusion In endemic regions, brucellosis-associated myocarditis should be considered among infectious causes of myocardial injury with non-obstructive coronary arteries. MINOCA is a working syndrome rather than an etiologic diagnosis. When cardiac MRI or endomyocardial biopsy is unavailable, epidemiologic exposure, microbiologic data, serial biomarkers, ECG evolution, echocardiography, and coronary angiography may support a probable diagnosis while acknowledging residual uncertainty.