I've defined a macro on host level base.
This macro is used on a template.
The Item name also includes a the macro

item name:
DB Connection Pool Size for {$DB1}

item value:
jmx[jboss.jca:service=ManagedConnectionPool,name={$DB1}][InUseConnectionCount] )

on latest Data is also only the macro to see.

and in my mind for triggers it is the same, but It must be verified