"Tied" to El-nino - no, i don't think so. Rather, both huge input of heat in the Arctic and El-nino could be tied to a same underlying cause, or few. But, "affected" by El-nino - yep, sure, definitely for some extent. To some small extent this year - i believe most affection from an El-nino itself takes several months to a year to arrive into Arctic, plus current El-nino is not yet "is", - but only developing (and i can't say it's developing rapidly or definitevely, 'cause it's not). Still, some affection there most likely already is - yet it's nothing like "the astonishing sea ice retreat of 2007 [which] occurred during an especially strong el Nino", of course.