Extrinsic 18398-1

{
  "heartbeat": {
    "blockNumber": 18397,
    "sessionIndex": 306,
    "validatorsLen": 4,
    "authorityIndex": 3
  },
  "signature": "0x8469011ecb3c6540d58295fd422ed64b5eda9ec59645c8097b24f946bad179349f91dc4a4e4a7cb7426ec2942c28dd822ebc1cad08bb0633faf86d5f39ccba87"
}