Does the mechanical valve make noise? I read somewhere that you can actually hear it.
It sounds like a watch ticking. I don't hear it all the time. In a quiet car, in the bathroom, in bed at night - is when I hear it the most. Sometimes my husband can hear it. But when I'm moving around, or there's an air conditioner running, or an aquarium pump, or a tv, or walking through the mall? Nope, can't hear it. My sister couldn't hear it even with a stethoscope.
Do you have a normal sounding heartbeat when the doctor just uses a stethoscope?
It totally depends on the doctor! I had the murmur (that I knew about) for 10 years. At a D.O.T. physical in year 8, the RN said to me, "That's a nice strong and solid heartbeat you've got, no problems there!" I about fell off the exam table!