Help with slow query - Pgsql 9.2

Hi guys,

I got this query:

> SELECT id,jobid,description,serialised_data
> FROM logtable
> WHERE log_type = 45
> AND clientid = 24011
> ORDER BY gtime desc

Explain analyze: https://explain.depesz.com/s/XKtU

So it seems the very slow part is into:

-> Bitmap Index Scan on "ix_client" (cost=0.00..5517.96
> rows=367593 width=0) (actual time=2668.246..2668.246 rows=356327 loops=1)
> Index Cond: ("clientid" = 24011)

Am I right? The query is already using an index on that table... how could
I improve the performance in a query that is already using an index?

Thanks
Patricl