Extrinsic 18548-1

{
  "heartbeat": {
    "blockNumber": 18546,
    "sessionIndex": 309,
    "validatorsLen": 1,
    "authorityIndex": 0
  },
  "signature": "0xd24e8d1a9b72d5c3ad9d2d0fef88a0597c818f5b29f8063c02779e65aff8205f4b76d38b61d181b4c82513992aefdb7745813489430d1b0d0d28833c1b89c282"
}