Extrinsic 1664-1

{
  "heartbeat": {
    "blockNumber": 1662,
    "sessionIndex": 27,
    "validatorsLen": 4,
    "authorityIndex": 2
  },
  "signature": "0x3ad774c2a6a6d81b83978122264097fe6dc0d3a2b27cc1c26cf95feab243be30b06bdafd8ccd2d0b9c70c3a5a6b90b67092cb32d08f651e9383adab97ed7908c"
}