How to send many metrics from Topbeat to CloudWatch with logstash


I'm trying to send some inputs from Topbeat to Cloudwatch, but I do not know how to obtain more than one metric, as if I put them into an array, only the first one is obtained.

I attach my config file (In cloudwatch I obtain the metric "Load1" but does not appear "Load15"):

input {
beats {
port => 5044
codec => "json"

filter {
if ([type] =~ 'system') {
add_field => ["CW_metricname", ["Load1","Load15"]]
add_field => ["CW_namespace", "GetStarted"]

output {
cloudwatch {
access_key_id => "my_access"
secret_access_key => "my_secret"
region => "myregion"