6♥ was explained as a cue bid. Since I'd already guaranteed that we have all the aces, I didn't need to know about that, so I assumed it was showing the king (even though the explanation correctly said 8+ 8421 points).
It turned out all right, as it was able to discard the heart losers on my clubs.

Help

1♦ 1♥
1♠ 4N
5♥ 5N
6♣ 6♦
6♥ 7♠
AP