How to replace,remove txt inside custom field?

example my custom field shows <?php echo get_post_meta($post->ID, name, true); ?>

JuanCarlos

i dont want to be editing post idiviualy i just want a code that can do this by itself almost like

<?php echo str_replace

istead of JuanCarlos i just want to show Juan and remove Carlos

how can i do this

i try this
<?php echo str_replace(‘Carlos’, get_post_meta($post->ID, name, true); ?>
but is not working!

thanks