AMI Queue Events


I am working with the AMI to get the current state of the Queues and update the state as new events come in. I am currently using the QueueStatusAction to get the initial state of the queue via the QueueParamsEvent. The issue I am having is that the only post initalization event that I can use to update the state of the queue is the QueueSummaryEvent however this is an event generated by an action. Is there any other event that will be fired when the queue statistics change that does not need to be instantiated by an action? I really do not understand why the QueueSummaryEvent is action generated and not simply a fired event.