Hello Nikolay,

Maybe one possible approach to achieve the desired behavior could be if you handle FillSceneGraph event.  There you could check the values of each point and deside what to do (to draw the line or not). I made small sample where I remove the part ot Line which falling down to zero value. Please take a look at the attached sample for more details and if you have any questions, do not hesitate to write us.

private void BurnDownChart_FillSceneGraph(object sender, Infragistics.UltraChart.Shared.Events.FillSceneGraphEventArgs e)
{
    foreach (Primitive pr in e.SceneGraph)
    {
        if (pr.Row != -1 && pr.Column != -1 && pr.GetType() == typeof(Polyline) && Convert.ToInt32(((Polyline)pr).points[1].Value) == 0
            && Convert.ToInt32(((Polyline)pr).points[2].Value) == 0)
        {
            pr.GetPrimitives().Clear();
        }
    }
}