Extrinsic 18375-1

{
  "heartbeat": {
    "blockNumber": 18373,
    "sessionIndex": 306,
    "validatorsLen": 1,
    "authorityIndex": 0
  },
  "signature": "0xdc37b59985c9720e02bfbe224658020c4e2c9d4393f00c1987f4fa8f4920f94b7d8297399068ef072d606b5e78e74d3e58dad16adc905a58edbab58de9ff808f"
}