Cassandra/Astyanax - filter by column/key value range

Cassandra/Astyanax - filter by column/key value range

I have a column family with records that look like this:
RowKey: wedding+playlists 2013-08-06 EN
=> (column=Date, value=2013-08-05, timestamp=1375772630931000)
The key is made up of 3 fields in my application and I have an index on
the Date column:
{column_name : 'Date',
validation_class : UTF8Type,
index_name : 'date_idx',
index_type : 0}.
I'm not sure if the 3 fields key is correct. Perhaps I need to remove the
date from it?
Is there a way of filtering the returned results by the date value by
Cassandra, or do I need to do it in code? the problem is I don't have an
exact value for the date against which to check: it should be inside an
interval (last week to now).