Delete Attached File From ListItem

public void DeleteAttachedFileFromListItem(string siteUrl, string webName, int itemId, string attachmentFileName, string listName)
{
    using (ClientContext clientContext = new ClientContext(siteUrl))
    {
        //http://siteurl/lists/[listname]/attachments/[itemid]/[filename]
        string attachmentPath = string.Format("/{0}/lists/{1}/Attachments/{2}/{3}", webName, listName, itemId, Path.GetFileName(attachmentFileName));
        var file = clientContext.Web.GetFileByServerRelativeUrl(attachmentPath);
        file.DeleteObject();
        clientContext.ExecuteQuery();
    }
}