Percutaneous transluminal angioplasty (PTCA) has been performed worldwide since 10 years and in Graz since 1980. 1977 6 procedures were performed, 1987 about 100,000 will be done worldwide. PTCA today represents a standard treatment of coronary heart disease in addition to pharmacological and surgical therapy. At the present time about one third of patients with coronary heart disease are treated by PTCA. Primary success rate ranges between 80 and 90%, complication rate has dropped under 4%. Besides patients with one-vessel-disease also those with multi-vessel-disease, reduced left ventricular function and patients with unstable angina and acute myocardial infarction are dilated. The "achilles" heel of PTCA is restenosis, which develops in 25 to 35% of cases within 6 months. At present, research is devoted to avoid or prevent this complication.