ng-if do the trick! Thanks!
My example:
<ion-slide-box
does-continue = "true"
auto-play = "true"
ng-if = "sliders">
<ion-slide
ng-repeat = "slide in sliders"
style = "overflow:hidden;position:relative;height:300px">
<img
style = "position:absolute;margin:auto;left:-50%;right:-50%;top:0;bottom:0"
ng-src = "{{'http://www.dummy.ccc/images/' + slide.medio}}">
</ion-slide>
</ion-slide-box>