Jinksy, on 2014-March-04, 06:51, said:
As others have said - just bid normally and involve your partner. Partner has shown a decent hand and you have 8 points. There's no reason to curl up and die. Your side has 19 hcp, theirs 21. So it's not at all clear that they "own" the hand, especially when you have the spades.
If partner gets to raise your spades, as he likely will, you will know that you have an eight-card spade fit and, in all probability, an eight-card club fit. Having a double fit like that should make you want to bid (or pass), not double. It's true that you have a surprise in hearts and a trump lead might be a successful defense but double is speculative.
It will be a tough decision over 5♦ but, having described your hand well, partner will be in a much better position to make a decision over 5♦ than you. With Qx in diamonds he's unlikely to want to bid 5♠ (which could be down too many) but will also know that they might easily make 5♦, given that you couldn't overcall the 1♥ bid.
If your side does end up in 5♠X, you might easily win a few imps if you are able to hold the damage to down two.