Displaying a heading with nested repeats

My ideal markup looks something like:

```html
<tbody ng-repeat="item in itemgroups" vs-repeat>
  <tr>
    <td>{{ item.heading }}</td>
  </tr>
  <tr ng-repeat="thing in item.subitems">
    <td> {{ thing.content }} </td>
  </tr>
</tbody>
```

However, `vs-repeat` requires the `ng-repeat` to be the direct child of the first `ng-repeat`. How can I work around this limitation?