how to give back 1100

Last night I played a short IMP tourney on BBO. On the first board, we were lucky enough to receive a +1100 gift from our opponents. A board or two later, my partner opened 1 heart in third position and I have
♠ 4 3
♥ 8 7 6 5 4
♦ A 2
♣ 10 8 7 4
We're vulnerable, red versus white and both opponents passed. Still, I have decided to bid 3 hearts (weak in our system). That is a little bit over-aggressive but I blame the -1100 which followed on partner opening, which was:
♠ Q J 5
♥ K 9 3 2
♦ Q J 6 3
♣ Q 9
Full bidding: p - (p) - 1♥ - (p); 3♥ - (DBL) - all pass.

I think this board is an useful exercise in blaming partner ;-) Seriously now, look at his hand, I would really consider passing it. Slow values, a hand which scream 'defend, defend!'.

Also, even if we accept opening with only 4 card in majors in this position, there should be a reason:
- lead directing (good suit). is this case, 1♥ is not better than 1♦
- preempting. in this case, 1♥ preempts nothing more than 1♦
Do not open a 4 card major (in a 5 card majors system) just because you can.

Now, I wait for my partner comments on how bad was my 3♥ call, with a semi-balanced hand, 9 losers etc ;-)