Key Clinical Message Heart failure due to ANCA‐negative vasculitis, is a rare potentially life‐threatening manifestation of ANCA vasculitis. Therefore, physicians must always pay attention to this manifestation for proper disease diagnosis and treatment. Abstract Less than 10% of primary vasculitides cause cardiac dysfunction, with Takayasu's arteritis, polyarteritis nodosa, and eosinophilic granulomatosis with polyangiitis being the most common cases. However, any cardiac tissue can be affected by ANCA vasculitis. We present a case of heart failure with reduced ventricular ejection fraction due to ANCA negative‐vasculitis.