update pg_index set indisvalid = false where indexrelid = 'sometable_pkey'::regclass;
UPDATE 1

                                                             QUERY PLAN
-----------------------------------------------------------------------------------------------------------------------------------------
 Limit  (cost=325686.01..325686.26 rows=100 width=259)
   ->  Sort  (cost=325686.01..326215.02 rows=211604 width=259)
         Sort Key: id DESC
         ->  Bitmap Heap Scan on sometable  (cost=2509.00..317598.66 rows=211604 width=259)
               Recheck Cond: (((hstore_col -> 'email'::text) = 'randomemail'::text) AND ((col4)::text = 'sometext'::text))
               ->  Bitmap Index Scan on index_hstore  (cost=0.00..2456.09 rows=211604 width=0)
                     Index Cond: ((hstore_col -> 'email'::text) = 'randomemail'::text)
 Settings: effective_cache_size = '32GB', jit = 'off', max_parallel_workers_per_gather = '0', random_page_cost = '1.1', work_mem = '64MB'