$22t AKo in the BB - Bubble question

[pkrPlayerBr]

I need to know what to do in a situation like this...
The player had pushed many times before during t400 and also t600. He understood the situation, and was putting pressure everytime it was folded to him and I was in the bb.


PartyPoker $22 Speed Tournament, Big Blind is t600 (4 handed) Converter on pregopoker.com

CO (t3445)
Button (t2460)
SB (t10045)
Hero (t4050)

Preflop: Hero is in BB with K[img]/images/graemlins/heart.gif[/img] A[img]/images/graemlins/spade.gif[/img]
<font color="gray">CO folds</font>, <font color="gray">Button folds</font>, SB calls t300, <font color="red">Hero ????</font>

<font color="red">What should I do?</font>