bypass complications

I had stents in November of 2007, placed by an intern being trained - they failed and I had a heart attack in January of 2008, two months after the stents.  I was taken to the hospital where I was sedated and woke up having gone through a five graft bypass.  It's been one year - about four months ago I began having angina again when walking fast.  My cardiologist is suggesting I go in for another catheterization, but while I'm trying to decide on that, he has me on Ranexa.  I've heard of EDTA and chelation therapy as well.  I'm extremely frightened, confused about what's best, and now I'm slipping into depression.  I'm at the point of hopelessness.  I've never heard of anyone having issues after going through bypass.  Is it common or am I the exception?

[kenkeith]

The installation of stents requires skill, and it is possible there was restenosis and required a bypass.  

The harvested vessel for a bypass can devleop the same problems of the natural vessel, but there should not be any related heart problems for many subsequent years.  There could be blockage of the bypass or another vessel and that would be the underlying cause for the angina.  If the medication does not provide relief from angina, then a stent implant is the best option.