Will my fiancee's vp shunt malfunction after almost 30 years?

[Bjc2278304]

My fiance has Spina Bifida myelomeningocele. She is now 29 and has been stable since she was young. She had a shunt put in when she was days old which either malfunctioned or got infected and a new one was relocated a few days later which has never caused any problems in almost 30 years. She had a revision done when she was in kindergarten to lengthen the tube for growing but that's all that she has ever had done. My questions is that in my research online has shown that shunts usually malfunction long before 30 years. Is this something that's going to go wrong anytime or should it be stable for the rest of her life. Is it possible she has outgrown the use of it and it's just sitting there not being used? She is reluctant to see a doctor as she has never experienced any problems. Should I force her to see a neurologist? We're getting married soon I want to make sure she's not in any danger.