Nic Dowd tied it 1-1 at 4:50. He skated behind the net, took a pass from Ivan Miroshnichenko at the right side and slid a backhand past Varlamov.
Wilson gave the Capitals a 2-1 lead at 12:10, completing a tic-tac-toe passing sequence with McMichael and Strome by scoring from the slot.
Lee tied it 2-2 at 1:15 of the second period when he redirected Dobson’s shot past Thompson.
John Carlson appeared to give the Capitals a 3-2 lead at 14:05 during a delayed penalty, but the goal was overturned after the Islanders challenged for goaltender interference.
Kyle MacLean put New York ahead 3-2 at 16:28, converting a pass across the slot from Horvat.
Holmstrom then extended it to 4-2 at 18:09 when he scored in the slot with a deflection of Dennis Cholowski’s shot from the left point.
“Second period [we] dug ourselves a hole,” Capitals coach Spencer Carbery said. “We could have let that determine the game and we didn’t. So that’s what you appreciate about the group.”
NOTES: Roy said Pageau is day to day. … Lee got an assist on New York’s first goal for his 200th in the NHL. … Chychrun and Strome each has six points (two goals, four assists) in a three-game point streak.