What is respective branch? (suggested by ReSharper)

I am using ReSharper to refactor my code, and one of the suggestions of ReSharper is to use a respective branch instead a if statement that is always true.

If I have

if (myVar != null){
   //code
}

And I apply the respective branch the code is like the following

{
   //code
}

Is this a short cut of an if statement? What is this used for? What is the difference between the cutely brackets and nothing?

Thanks in advance.