Bicuspid Aortic Valve and LBBB

After taking a routine physical for the local fire department, my 19-year old son was told that his EKG showed that he has left branch bundle block.  He is 6'0" tall, 185 pounds, exercises regularly and has no symptoms of anything whatsoever.  He then went for an echocardiogram and the cardiologist just called to tell us that my son has a bicuspid aortic valve. He gave us very little information, and I really didn't know what to ask while I had him on the phone. Since my son is away at college, his follow up appointment is not until November! Naturally, we are worried and have lots of questions.  What causes this?  I had a brother who died at 2 years of age from Tetrology of Fallot, and I have a few second cousins who have had the same condition.  Is that related to what my son has?  (Otherwise, we have no heart problems in our families.)    I know people who have a bicuspid valve and their  EKG's are normal. Does the bicuspid valve cause the LBBB?  Should we be worried about this?  Can he continue to do cardio exercise? Should he get a second opinion? Any info would be appreciated because we are having a hard time finding info about both LBBB and bicuspid valve together.