I use this code to get a String array of headings used in a MS Word 2007 document (.docx):
dynamic arr = Document.GetCrossReferenceItems(WdReferenceType.wdRe
try
object arr_r = Document.GetCrossReferenceItems(WdReferenceType.wdRefTypeHeading); Array arr = ((Array) (arr_r)); string myHeading = (string) arr.GetValue(1);