Puoi usare diversi modi, ad esempio:

codice:
Private Sub lvwTest_ItemSelectionChanged(ByVal sender As Object, ByVal e As System.Windows.Forms.ListViewItemSelectionChangedEventArgs) Handles lvwTest.ItemSelectionChanged
    If e.IsSelected Then
        MessageBox.Show(e.Item.SubItems(1).Text)
    End If
End Sub