H-1B landing in Canada!!!

Hi Guys:

I came to US as a F1 student, I am holding an H-1B in US now. This H1B is transferred from F1 in US. I haven't left US since I got the H1B visa.

I have applied for Canadian Immigration. If after I get approved, how could I land in Canada and then come back to US without applying for a new H-1B to come back? I don't want the risk to have a stamp on the passport, but I don't want to lose the chance to immirgrate to Canada as well...

Anybody knows how to do, Please help...