<?php
$args = array(
    \'posts_per_page\' => -1,
    \'post_type\' => \'event\',
    \'meta_query\' => array(
        array(
            \'key\'     => \'event_date_end_timestamp\',
            \'value\'   => time(),
            \'type\'    => \'numeric\',
            \'compare\' => \'<\'
        )
    )
);

$programs = new WP_Query($args);
?>
<?php while($programs->have_posts()): $programs->the_post(); ?>
    <h1><?php the_title(); ?></h1>
<?php endwhile; ?>