The PHP's Boolean operators always return a Boolean value... as opposed to other languages that return the value of the last evaluated expression.
But you may do something tricky like:
$echo=$myVar or $echo="something else";
It will work with a notable exception: when $myVar=0. In this case the assignment $echo=$myVar is evaluated as Boolean false.
Or you may simplify the ternary operator like this:
echo ($myVar?$myVar:"something else");
But, again, $myVar can have any value except 0, because 0 is evaluated as Boolean false.