Extrinsic 8711-1

{
  "heartbeat": {
    "blockNumber": 8710,
    "sessionIndex": 145,
    "validatorsLen": 4,
    "authorityIndex": 2
  },
  "signature": "0xbc86506c3dbf1492bdf14ba4144de719f3f0172a08750e03f8843b9eedf91e0b37a912933c8c0fa2d70b16d053aacb4aa4a3b912eb39d231a25d3596803d6b8f"
}