AbdulAlhazred
Legend
Logically, if a race has a preference for heavy blades and wishes to use a heavy blade as a thrown weapon they would develop such a weapon.
There are two "real world" thrown weapons that I can think of that fit within the heavy blade group, but are not yet described in any 4E book I have seen; The mambele (African throwing iron) and the chakram (razor edged iron or bronze discus).
As military weapons: Prof: +2, Dam: 1d6, Rng: 6/12, Price: 10gp, W: 3lbs, Group: Heavy Blade, Prop: Heavy Thrown. (similar to the Xen'drik boomerang but no automatic return with proficiency)
As superior weapons: Ditto except Prof: +3.
In all fairness, if a membele isn't an axe, what is? It may be a single piece of metal but you're going to use it like an axe and it really should be in the axe group (and in fact really might as well be statted up as a hand axe).
I'd be somewhat skeptical of calling a chakram a HEAVY blade either. Doesn't really seem at all close functionally to other blades and is more of a specialist unique weapon.
I think the whole point with heavy blades is their design is rather mutually exclusive with being effective throwing weapons since their advantages are speed and reach more than anything. Long thin relatively straight blades of a heft beyond comfortable throwing weight just don't ever make good ranged weapons.