Transplant coronary artery disease is the greatest impediment to long-term survival beyond the first year after cardiac transplantation. Transplant coronary artery disease shows a heterogeneous angiographic appearance, but focal stenoses can occur alone or at least predominate. Based on an angiographic indication 35 critical focal lesions causing narrowing by 75% or more were treated by PTCA during 23 procedures in seven patients 18-84 months after cardiac transplantation. Three patients each underwent only one procedure and four underwent repeated procedures [2, 3, 4 and 11, respectively). Primary success was achieved without any complication in 35 of 35 lesions (100%). The mean degree of stenosis was reduced from 86 +/- 9% to 28 +/- 17% (P < 0.001). The rate of restenosis was 18/29 (62%) at a mean of 4 months after angioplasty. Four patients are alive and free of adverse effects (symptoms, myocardial infarction, repeated percutaneous transluminal coronary angioplasty, retransplantation) 16 +/- 10 months after their last angioplasty. One patient underwent a successful second heart transplantation 26 months after the first angioplasty. Two patients died, 1 and 31 months after the last angioplasty. In conclusion, percutaneous transluminal coronary angioplasty can be performed safely with an excellent primary success rate in critical focal transplant coronary artery disease. The rate of restenosis is higher than in native coronary artery disease. Long-term follow-up depends on the individually variable accelerated nature of graft atherosclerosis.