Irslinger, a music teacher from Arendal on the southern tip of Norway, was met with cheers and applause as she let loose the final triumphal chords of her organ marathon.
She was then carried out into the packed stalls of Arendal church in a victory procession, where champagne was served.
Irslinger has been itching to take her record back ever since her Canadian nemesis Jacqueline Sadler snatched her record for the longest organ marathon, as approved by the Guinness Book of Records, in 2011.
Sadler, a member of the United Church of Canada, played hymns from the church's official hymnal for a full 40 hours and 36 minutes, beating the 36-hour record Irslinger had set with an earlier marathon in 2009.
Between Saturday and Monday Irslinger played almost continuously, in a stunt timed to celebrate her 60th birthday.
She allowed herself only one five minute break each hour.
Her feat has yet to be officially recognised by the Guinness Book of Records.