Extrinsic 8373-1

{
  "heartbeat": {
    "blockNumber": 8372,
    "sessionIndex": 139,
    "validatorsLen": 4,
    "authorityIndex": 0
  },
  "signature": "0xb64447da132fe9f1c1753c77bba89bb6096584fe0cb5d50b8f8df415bbc38f08d6f2005bcc9107776ef6b34dddff1592f0d00d5d2603d2744ddadff5e48fad83"
}