Extrinsic 1608-1

{
  "heartbeat": {
    "blockNumber": 1604,
    "sessionIndex": 26,
    "validatorsLen": 4,
    "authorityIndex": 1
  },
  "signature": "0x7422c57765169f44776e46a289dbe5da3a6eaeab9d2a5de1991c408f375d1c45f31e5f611844655d4bdd9e0cd5e687a317d374af04c5a8328dbd391f7858d288"
}