One year ago March 16th I had a quadruple bypass. Two weeks after the surgery I saw my surgeon (who bore a striking resemblence to Dougie Houser) and specifically asked about getting back on the bike. He joked as to whether I planned to ride home 30 miles away....but seriously he suggested some very common sense things. First of all not to initially push myself too hard..you body has been through quite a jolt...if you get to see an xray of your chest wired together like the safety wires on a airplane engine you begin to realize the extend of what you have been through. Most importantly initially he focused on not getting into any situation that might lead to a fall. Not wanting to go through a repair on his work I chose to cool it. The following week I did get back on and ride up and down the street.I found it very uncomfortable on my road bike, and thus used my sons mountain bike for a while. for me a more than adequate restart to my cycling. As I went through a hospital directed cardiac rehab program I began to utilize their stationary bikes more and more...inspired I might add by a very large poster of Lance A. hanging at the front of the rehab facility.
By the time I finished the 36 rehab sessions a month and a half later, I was back on my bike regularly, and without pushing myself too hard could easily do 25-30 miles. I would suggest working with your cardiologist, and a rehab program if available. The bypass creates new passageways for the blood supply but we can still have some serious problems if we jump back into play too quick. One of the sad parts of the rehab was meeting folks who had been back two or three times for additional surgery because the took it upon themselves to "test the system".
All my best to you for a very speedy recovery...and welcome to the secret society of the zipper club.