With ListView1.Items.Add("50")
            .SubItems.Add("100")
            .SubItems.Add("140")
            .SubItems.Add("150")
        End With

For Each lvi As ListViewItem In Me.ListView1.Items
    Dim v1 As String = lvi.SubItems(0).Text
    Dim v2 As String = lvi.SubItems(1).Text
    Dim v3 As String = lvi.SubItems(2).Text
    Dim v4 As String = lvi.SubItems(3).Text
Next

For Each .....
    Dim v1 As Integer = Integer.Parse(lvi.SubItems(0).Text)
    Dim v2 As Integer = Integer.Parse(lvi.SubItems(1).Text)
    Dim v3 As Integer = Integer.Parse(lvi.SubItems(2).Text)
    Dim v4 As Integer = Integer.Parse(lvi.SubItems(3).Text)
Next

Dim i As Integer
For i = 0 To Me.ListView1.Items.Count -1
    Dim lvi As ListViewItem = Me.ListView1.Items(i)
    Dim v1 As String = lvi.SubItems(0).Text
    ' .....
Next