Interesting handle! I also have mitral valve prolapse, and take xyzal, and flonase (like nasonex) for allergies. I've taken 40mg of Protonix twice a day for 5 years without any side effects. I feel very comfortable with this drug, although I know how hard it is to take something new, when you read all the extreme side effects it might have. My doctor has me researching an osteoperosis drug that has some pretty scary possible side effects. I can see why you'd worry.
You are the one who ultimately decides, but I wouldn't hesitate to take the Protonix if it is helping you. I had the GERD surgery in February (mainly for the uncontrollable asthma it caused) and still take Protonix every other day, due to my very reactive stomach. Hopefully in a year or so, when the healing is complete, I'll be able to try getting off it, but my family doc (who really knows my stomach), isn't in a hurry to get me off, and thinks I'll need it at least intermittently, always. My surgeon told me I could stop immediately, but I have a terrible stomach, so I'm hanging on to it a bit longer.
I think you'll find lots of people here who've been taking Protonix for a long time. I don't think you need to worry. If it's relieving your symptoms, be thankful, and take it! Of course this is a decision best made between you and your physician.
I'm glad you've joined us. This is a great forum with lots of very supportive and knowledgeable members.
I'm sure others will be by to comment.