Call for medic!
While answering the questions of the fans, Dustin Brawder confirmed that the next hero, who will pass via the portal, will be the medic from StarCraft. The date of the introduction of a new hero is yet to be announced. It is rumored that she will appear in late September. Now that many professional support players finished the season with 4 heroes, the introduction of new support will be much welcomed.
There's little information about the medic. We don't know her name, but some of the details of the hero's abilities are known. According to the information provided by the developers during various conferences, the medic will have a powerful healing ability, which will work on one aim, and will differ from the available abilities of Uther, Rehgar, Malfurion and other support heroes. One of the hero abilities will be the summon of Medivac - special transportation capable of transporting ally hero from one point to another. The team of the developers is going to make the hero rather complicated and "demanding" to the skills of the players.
Apart from medic, one more hero of StarCraft Universe will be added to the game. Protoss Artanis will be the first fighter from this Universe in HotS. There's no information on new maps. However, we know for sure, the introduction of StarCraft content won't be supported by the events like Eternal Conflict. It is also unknown if the medic will be added along with a new patch, ore separately.