Extrinsic 3500-1

{
  "heartbeat": {
    "blockNumber": 3499,
    "sessionIndex": 58,
    "validatorsLen": 1,
    "authorityIndex": 0
  },
  "signature": "0x8ad35da693f81ef440fe5e3064358b8aa4aac81f276e839ca92e984edf072a188cfb22ec70e936cc4f62945b4ef1c63255a119f3aab4e29bf407818ea4f3ba86"
}