use Data::Dumper;
my $href = {
             elem1 => { attr => 12, attr2 => 44 },
             elem2 => { attr => 12, attr2 => 44 }
};
delete $href->{elem1};
print Dumper($href);
__OUTPUT__
$VAR1 = {
          'elem2' => {
                       'attr2' => 44,
                       'attr' => 12
                     }
        };