A 31-year-old male who had been treated for Churg-Strauss syndrome (CSS) presented with sudden onset of dysarthria. Brainmagnetic resonance imaging (MRI) showed acute multifocal bilateral cerebral infarctions suggesting embolic causes. CardiacMRI showed dilated cardiomyopathy with severe biventricular dysfunction with intracardiac thrombi, and multiple high signalintensity spots in myocardium of the left ventricle with multifocal delayed enhancement suggesting multifocal myocarditis dueto small vessel vasculitis associated with CSS. After anticoagulation therapy, treatments for heart failure, and immunosuppressivetherapy including parenteral steroids and cyclophosphamide to control CSS, the symptoms and signs of heart failure and cardiacfunction of the patient were improved. Considering the pathophysiologic mechanism of cardiac involvement in CSS,immunosuppressive therapy to control the disease activity of CSS should be taken into account, besides usual management forheart failure.