Recently, we released a new feature part of the DataBoundListBox, called "Pull to Refresh".
Help Article: http://www.telerik.com/help/windows-phone/raddataboundlistbox-features-pulltorefresh.html
Since the SlideView uses the DataBoundListBox internally, the "Pull to Refresh" functionality can be used out of the box, as described in the article above. In addition, you can take a look at the "Pull to Refresh" example, which is part of the Telerik Examples available on the Windows Phone Marketplace.
Give it a try and let me know how it works for you. I'd be glad to assist you further.
the Telerik team