McQuarrie and her Lethbridge Curling Club rink of Rita Tarnava, Barbara Davis and Jane Rempel won the 1977 Macdonald Lassies Championship, Canada's national women's curling championship.

The team represented Alberta at the Canadian national championship, finishing with a 9-1 record to claim the title.

[1] McQuarrie, Davis and new teammates Gayle Pilling and Diane Smummach won another provincial title in 1979.

[2] Representing Alberta at the 1979 Macdonald Lassies Championship, McQaurrie led her rink to a 6-4 record, missing the newly added playoffs.

[3] Myrna was married to Jim McQuarrie, a fellow curler,[4] who won the 1979 Alberta Mixed Championship.