API: item.get filter by lastvalue?

[StealthJoe]

I'm trying to query the API via item.get. I'm specifically looking to filter only results that return a specific lastvalue but it always returns everything and seems to ignore the filter. Is this possible?

"jsonrpc": "2.0",
"method": "item.get",
   "params": {
      "application": "App1",
      "filter": {
         "lastvalue": "1"
       },
      "countOutput": true
   }

I have tried variations of this with no luck.