Vartmann started skating at the age of five in her home town of Neuss. Four years later she changed to Düsseldorfer, the club she currently represents. In January 2004, she turned to pair skating and was partnered with Florian Just.
They trained in Dortmund and Berlin.
The pair split up in 2009, just after the North Rhine-Westphalia Trophy. In 2010, Vartmann teamed up with Canadian-American Aaron Van Cleave to compete for Germany.
Their coach is Knut Schubert. Their first major international event was the 2012 European Championships.
On 26 January, during the morning practice before the long programs, Vartmann collided with Daniel Wende while they were attempting to avoid a French couple.
Vartmann and Van Cleave finished 5th at the event. Vartmann and Van Cleave withdrew from the 2012 Nebelhorn Trophy following the short program – Vartmann picked into her right foot when she fell on a throw triple loop during the short and was unable to put on her skate the next day due to swelling. They withdrew from the 2012 Coupe de Nice and their first assigned Grand Prix event, the 2012 Cup of Russia, after Van Cleave sustained a broken cheekbone while catching Vartmann on a triple twist.
They later withdrew from their second General Practice, the 2012 Nippon Hōsō Kyōkai Trophy.
In the 2015-2016 season, Vartmann started skating with Ruben Blommaert. Vartmann is of Japanese and German descent.
With Van Cleave