1♥ = 11-15, 5+ hearts
XX = 9+, tends to deny heart fit
So you're sitting West, and it's your turn after this sequence (some might disagree with the initial redouble, but it's forced by the system). You doubled 1♠ to suggest a penalty (some might disagree again, but they're vulnerable) and partner bid 1NT (probably misunderstood your double) so you're basically sure he has Jxxx or so in spades. Something weird is going on. What do you do now?