I don't know what her heart rate is & they didn't tell me how severe they just told she needs to see a cardiologist.
You probably mean "Right axis deviation". (RAD)
RAD means that electrical forces in the heart goes towards right, rather than left, which is most common, because the left chambers of the heart contains more muscle mass than the right (after all, the left chambers are responsible for pumping blood around the body, while the right chambers are only responsible for pumping blood into the lungs for oxygenation).
There are lots of reasons for RAD. In young people it can be a completely normal finding (as young people often have more rightwards electrical axis than older, because with increased blood pressure (with age) the left heart chamber tends to grow). It can be caused by a rapid heart rate (the electrical axis goes towards right when heart rate increases above 100 and towards 130 - then it for some reason turn left again if the heart rate is even higher). But it can also be caused by increased work load on the right heart chamber, like high pressure in the pulmonary arteries, pulmonal disease, or a blood clot.
How rapid was her heart rate? And more important, how severe was the RAD? Slight RAD can, as mentioned, be completely normal.