OBJECTIVES: We sought to evaluate the safety and efficacy of percutaneous transmyocardial revascularization (PTMR) in patients with refractory angina caused by one or more chronic total occlusions (CTOs) of a native coronary artery. BACKGROUND: Previous unblinded, randomized trials of PTMR in patients with end-stage coronary artery disease and refractory angina have demonstrated significant relief of angina and increased exercise duration. Whether such benefits would be realized in blinded patients with less extensive coronary artery disease is unknown. METHODS: A total of 141 consecutive patients with class III or IV angina caused by one or more chronically occluded native coronary arteries in which a percutaneous coronary intervention (PCI) had failed were prospectively randomized, at 17 medical centers, in the same procedure, to PTMR plus maximal medical therapy (MMT) (n = 71) or MMT only (n = 70). Blinding was achieved through heavy sedation, dark goggles and the concurrent performance of PCI in all patients. RESULTS: Baseline characteristics were similar between the two groups. A median number of 20 laser channels were created in patients randomized to PTMR. At six months, the anginal class improved by two or more classes in 49% of patients assigned to PTMR and in 37% of those assigned to MMT (p = 0.33). The median increase in exercise duration from baseline to six months was 64 s with PTMR versus 52 s with MMT (p = 0.73). There were no differences in the six-month rates of death (8.6% vs. 8.8%), myocardial infarction (4.3% vs. 2.9%) or any revascularization (4.3% vs. 5.9%) in the PTMR and MMT groups, respectively (p = NS for all). CONCLUSIONS: In patients with class III or IV angina caused by nonrecanalizable CTOs, the performance of PTMR does not result in a greater reduction in angina, improvement in exercise duration or survival free of adverse cardiac events, as compared with MMT only.