CAD tip # 1203:

Sub test()
    Dim blkdef As AcadBlock
    Dim elem As Object
    Dim strPrompt As String
        
    On Error Resume Next
    Set blkdef = ThisDrawing.Blocks.Item("TEST")
    For i = 0 To blkdef.Count
        Set elem = blkdef.Item(i)
        If StrComp(elem.EntityName, "AcDbAttributeDefinition", 1) = 0 Then
            strPrompt = elem.PromptString
        End If
    Next i
End Sub