For 4 weeks I had a stentimplantation. My bypass was 90 % blocked. ( bypass of circumflex arterie). A freezing woke me several times at night and I had to take sometimes a nitro by going uphill. But not much has changed after the stent. I am still waking up every night of freezing. Several times up the early morning hours. For me it is beginning angina pectoris. I am not sure, if the bypass ist still open. The family doctor will test electrolytes tomorrow. Before the stentimplantation the doctor could not see any abnormal tracings in my EKG. So the only possiblity to really know were a new catheter examination. I am afraid to have done it, because the bypass is so old (26 years.) The symptom is only freezing. No pain. HAS ANybody the same symptom?