The AltComment property returns or specifies the alternative ("Alt") comment of a URL.
Examples:
The following VBA example displays all alternative comments contained in the active page.
Sub Test()
Dim sh As Shape, s As String
For Each sh In ActivePage.Shapes
If sh.URL.AltComment <> "" Then
s = s & sh.URL.AltComment & vbCr
End If
Next sh
MsgBox "The current page contains the following URL alternative comments: " & _
vbCr & s
End Sub