YOU COULD HAVE A BIRTH DEFECT CALLED WOLF WHITE PARKISON SYNDROME ASK FOR A ECG AND THEY SHOULD FIND IT ON A ECG
Well. If it is a mitral valve issue and the click cn be herd without a stethoscope, it is in an advanced stage and other symptoms woud accompany the chest pain, such as; dizzyness, fatigue, shortness of breath...particularly when lying down. It could also be comming from the lungs. Inflammation would increase the problems assosiated with mitrl valve prolapse and a crp test should be given to check as well as a white count. But the best advise anyone could give you, would be a Doctor, AFTER they examine your husband. So get his butt in there!
There are different gradings of heart murmurs. A very mild one would be a #1. The very severe murmurs that can be heard without a stethoscope would be a #6. Some murmurs are turbulent flows, some are clicks related to the valves. The best thing for him to do now is see his doctor and probably get an echocardiogram done to see what's going on in there.
Sounds something like a mitral valve prolaps see:
http://www.dreddyclinic.com/findinformation/mm/mitralvalveprolapse.htm
You will have to copy and paste the above into you browser to get to the web site.
While MVP is know to make a clicking sound, I doubt that in most cases one could hear it without a stethoscope - but I do not know that to be the case.
You should probably at least have it checked out. Might me a murmur??