OBJECTIVE To evaluate the feasibility of cutting balloon percutaneous transluminal angioplasty (PTA) for treatment of neointimal hyperplasia in peripheral arterial bypass grafts. METHODS Fifteen consecutive patients (six women, nine men; age range, 57-89 years; mean age, 71 years) were treated with cutting balloon PTA for 16 anastomotic stenoses after infrainguinal bypass (prosthetic grafts, seven patients; prosthetic-vein composite grafts, two; venous grafts, five; and ileofemoral stent-graft, one). Cutting balloon PTA was followed by conventional PTA to improve anastomotic diameter. Patients with stenotic vein grafts underwent cutting balloon PTA after failed conventional PTA; the other patients were treated primarily with cutting balloon PTA. Criteria for success were a lumen diameter improvement of greater than 50% or residual stenosis of 20% or less. Follow-up was performed with color duplex ultrasonographic surveillance. Patency rates and durations were calculated with Kaplan-Meier survival curves and log-rank statistics. RESULTS Attempted conventional PTA (n = 6) prior to cutting balloon PTA was unsuccessful. Cutting balloon PTA was technically successful in 15 (94%) of 16 lesions, without clinical complications. Two local restenoses and one graft occlusion occurred between 5 and 7 months. The cumulative 6-month primary and secondary graft patency rates were 84% and 92%, respectively. At 12 and 18 months, they were 67% (95% CI: 0.34, 0.86) and 83% (95% CI: 0.48, 0.96), respectively; mean follow-up was 10.0 months. CONCLUSIONS Cutting balloon PTA proved feasible for treatment of resistant peripheral arterial bypass graft stenosis, commonly caused by neointimal hyperplasia, with excellent technical success. Short-term patency with this technique appears to be superior to that with conventional PTA, and it compares well with patency of atherectomy for salvage of infrainguinal bypass grafts.