I was South and may have doubled 2♠, although I don't think it would affect the result. Partner led the ♥9 (top of doubleton, we lead smallest from 3 small), and like the 3 other tables with the same lead against 4♠ we failed to beat it.
I won with the Q and switched to a small diamond. Partner won and continued hearts and it was smouth sailing for declarer (he won the Ace, drew trumps and established a heartdiscard for his losing club).
In the evening partner and me discussed this board. From my side the position is relatively clear at trick one, including the danger of a clubloser disappearing on a heart, so maybe I should win the first trick with the K? Partner also knows that I didn't bid 1♥, so maybe at clubswitch is indicated anyway? What do you think?