Horvat is Vancouver's captain and top scorer this season with 31 goals - ten more than Elias Pettersson.
In points, the relationship is the opposite, where Pettersson has 58 points against Horvat's 54.
After nine years at the club, 29-year-old Horvat has had difficulty agreeing on a contract extension.
His annual salary is SEK 60 million.
This weekend is the All Star game and Horvat and Elias Pettersson are selected to represent Vancouver.
On several NHL-linked pages, all information about Horvat and the Vancouver Canucks has been removed.
“Really looking forward to it”
It's part of the game to be traded overnight and Horvat is determined to help his new club the Islanders, who are now two points away from making the playoffs.
- It has been like a big whirlwind for me and my family right now.
I have heard tons of incredible things about the organization, the city and all the players in it and nothing but respect for this organization.
So I'm really looking forward to it and the family is looking forward to it, says Horvat about becoming a New Yorker to the NHL.
Instead of Horvat, Vancouver gets Anthony Beauvillier, the Finn Aatu Räty and a first pick in the draft by the Islanders.
Only one NHL game was played that night.
Winnipeg beat St. Louis 4-2.