To say you are in big trouble is an understatement. You are in desperate trouble. Your only chance is to play West for the stiff ♥K and ruff with the queen, play the ♥A and if the king falls (it does) arrange a trump coup against East’s four hearts to the 10.
The next step is a heart to the 9, overtake the ♠Q, cash the ♣K, discarding a diamond, and ruff a club reducing to East’s length. If the ♣Q has appeared, cross to a high spade and play the ♣J. In this three-card ending East has no winning option. If East ruffs, you overruff, draw East’s last trump, and your remaining diamond is high. If East discards, you discard the remaining diamond and take the last two tricks with the ♥J 8.
If the ♣Q does not appear, lead a spade to the 10 as you need an extra winner to stay in the dummy to complete your trump coup. Assuming the 10 wins, play a high spade, discarding your remaining diamond, and take the last two tricks with the ♥J 8. Your play caters to these two possible East–West hands:
Case #1
Case #2