The Missed Beats alarm becomes active when at least one heartbeat is missed on an HADR connection. Heartbeats are messages sent from one HADR database to another at a regular interval. They are a key indicator of the health of the connection between the databases. A high number of missed heartbeats indicate the condition of the connection is poor.
The default thresholds are defined as follows:
You can adjust thresholds to suit your environment using the Metric Editor.
Check your network connections for problems and resolve them as soon as possible.