Järventie played professionally for Ilves in Finland before coming to North America in 2021.

[2] Järventie was assigned to Ottawa's American Hockey League (AHL) affiliate, the Belleville Senators for the 2022–23 season.

[6] However, a recurring knee injury required surgery in late February, ending his season.

[7] On 15 July 2024, Järventie and a fourth-round pick for the 2025 NHL entry draft were traded to the Edmonton Oilers, in exchange for Xavier Bourgault and Jake Chiasson.

He was activated off IR on 25 October and assigned to Edmonton's AHL affiliate, the Bakersfield Condors.