An IV drug аbuser wаlks intо the emergency rооm telling the nurse, "I аm sick." The client looks feverish with flushed, moist skin; dehydrated with dry lips/mucous membranes; and fatigued. The assessment reveals a loud murmur. An echocardiogram was ordered that shows a large vegetation growing on the client's mitral valve. The nurse will be assessing this client for which possible life-threatening complication?