Drawing primitives on TH2D

ROOT
1

Hello,
I would like to add a line on top of a 2D histogram.
It works if I do:
hRadius->Draw("");
TLine *l1 = new TLine(-200,0,200,200);
l1->SetLineWidth(10);
l1->Draw();

but the line does not show up if I use:

hRadius->Draw(“CONT4Z”);

What can I do to plot a line on top of 2D histo plotted with CONT4Z option? 
Cheers,

   Mariusz
2