30 % of heart attacks are silent and/or unrecognized by the victim. Thus it is not at all usual to be in your spouse's situation. Your husband has a chronic 90 % occlusion in one artery that has developed what we call collateral circulation around the blockage; we see this all the time. This is the self-bypass that your spouse's cardiologist is referring to. Major lifestyle changes are also in order here---if your husband smokes, he needs to quit. He should follow a low fat, low cholesterol diet. Make sure he isn't diabetic. Control the blood pressure very well. Exercise daily if it is approved by the cardiologist. Visit americanheart.org for more helpful information. Good luck.