I responded to your post from 13 hours ago. If you scroll down a bit you'll see your older post and my response. I'll go copy and paste it to here for you.
"Hi, my grandson who has gone for his regular check up has been diagnosed with a heart murmur.
This a worry to us.
Can anyone tell us what this is and what will have to be done.
Thank you very much. "
It depends. Heart murmurs occur when a valve does not close all the way and some blood can rush backward during a heart beat. It's called regurgitation (just like the regular regurgitation). However, a HUGE portion of the human population have heart murmurs and they are considered benign and generally unimportant. The instruments out there today are so sensitive that they can pick up mild murmurs better than older instruments.
If your doctor reacted to this diagnosis by listening with a stethescope and saying, "Hmm, sounds like there is a bit of a heart murmur," and then moved on as though it was no big deal, then it isn't a big deal and is not a real concern. It's "normal" for your grandson and will not affect his life.
If the doctor reacted by listening a bit harder, ordering some follow-up tests, and suggesting alterations in lifestyle, then the murmur is more pronounced and will need to be monitored closely. In young children, it is not uncommon to have a pronounced murmur correct itself over time. Again, if the doctor is concerned, then there are very practical and successful procedures for heart valve replacement that would be available if the valve defect does not correct itself (again, this is ONLY if the regurgitation is pronounced and causes life altering symptoms/issues).
One more time, if the doctor fairly dismissed the murmur, nothing will need to be done. If he ordered follow-ups, then you'll need to follow-up and perhaps take preventative steps (prophylactic antibiotics) to avoid infections before procedures such as dental fillings etc. More serious issues will be followed up by your doctor or pediatric cardiologist.
Hope this helps.