Heartbeat API in Vanilla JS (addEventListener)

Hi guys!

Why following code written in jquery works great

<script>
    jQuery(document).ready( function($) {
        $(document).on('heartbeat-tick', function() {
            console.log('OK');
        });
    });
</script>

… but when I try to use it with vanilla js then it’s not working:

<script>
    jQuery(document).ready( function($) {
           document.addEventListener('heartbeat-tick', function() {
                 console.log('OK');
           });
    });
</script>