Open surgical sympathectomy has previously been shown effective in relieving severe angina pectoris. The method was hampered by high morbidity and mortality. The authors have developed a minimally invasive technique of dividing only the sympathetic chain endoscopically and obtained good results with no serious complications in patients operated on for severe palmar hyperhidrosis. This method was used in 43 patients with severe angina pectoris who were not eligible for coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. There was no mortality or any severe complications. Some 19 patients became symptom-free while 22 were improved and two unchanged after surgery. The frequency of anginal attacks was significantly reduced, as was the consumption of nitroglycerine tablets. The maximum exercise capacity was significantly increased and ST-segment depression reduced.