I am using the embeded content datatype to hold a list of links.  Each link has a tick box that when checked will format that link slightly differently.

To solve a layout issue I need to know how many of the links have this value set.  How can I could them when the EmbeddedContent property is returned as DynamicXml.

This is an example of the xml produced by the datatype

<navigationItems>
   <data>
      <item id="1">
         <anchorText propertyid="1">Royal Caribbean</anchorText>
         <anchorLink propertyid="2">1287</anchorLink>
         <isHeading propertyid="3">1</isHeading>
      </item>
   </data>
</navigationItems>

What I want to do is get a count of all the items that have isHeading set to 1.  But I'm not sure how to do so as it's dynamicxml.