Why would a physician send a patient home and say see you in 3 weeks, when they just told you that you have 40% blockage in main artery, your heart is functioning at 25% and you would not survive surgery?  Is this because they do not expect you to live past 3 weeks?  Also on dialysis.
Sorry to hear about it. Blockage of 40% is not considered a significant. I would like to know about the status of other arteries too. There might be blockage in other arteries too for which surgery is advised. So without knowing full CAG report It's difficult to comment. I would like you to INFORM that doing Surgery with heart function 25% is always a high risk surgery including death on table also.