That's a great question and I think you should ask many people the same question and you will get lots of different answers. I truly believe that it doesn't matter what your engineering degree is "named". It matters what you "do". Even if you majored in biomedical engineering from the beginning, what graduate schools and employers will want to know is, what projects did you work on? what skills do you have? You need to build tangible skills no matter what your degree is called. Programming skills, electronics, cad, whatever your strengths are, build on them and market them to future employers and schools. So find really interesting people to work with and really fun projects to do. THAT is what is important.