Extrinsic 19722-1

{
  "heartbeat": {
    "blockNumber": 19721,
    "sessionIndex": 328,
    "validatorsLen": 4,
    "authorityIndex": 2
  },
  "signature": "0xc208f91d142f5bcc8604215d0b1a2e831668b182e077afb87b4c26e4934d9c4f55f43933bb51ff6eef44488adcaad01efa1f8ab0524ec57cc48ec4f61b781f84"
}