Churg-Strauss Syndrome (CSS) is characterized by allergic rhinitis, asthma and prominent blood and tissue eosinophilia. Although CSS can affect any organ system, isolated cardiac manifestation is a rare feature that is often characterized by rapidly progressive congestive heart failure. We present the case of a 48-year-old woman with acute dyspnoea and chest pain. Her past medical history was significant for asthma and frequently relapsing minimal-change glomerulonephritis. Echocardiogram and coronary angiography revealed cardiomyopathy and coronary small-vessel vasculitis in the presence of blood eosinophilia and elevated IgE. In the absence of infective agents, neoplastic diseases and further vasculitic manifestations, a flow cytometry-based analysis of markedly elevated endothelial microparticles supported the diagnosis of CSS. Cardiomyopathy resolved completely after initiation of immunosuppressive treatment with corticosteroids and cyclophosphamide pulses. Elevated endothelial, leukocytic and platelet-derived microparticles decreased during follow-up and closely paralleled vasculitic activity. Endothelial microparticles might be an additional tool to diagnose and monitor cases of suspected vasculitic cardiac involvement in CSS.