Background: The optimal modality for stent restenosis remains unestablished. Cutting balloon angioplasty (CBA) is a strategy to reduce tissue injury and vessel stretch.Method: To clarify the efficacy and long-term outcomes of CBA for stent restenosis, we analyzed 167 lesions treated by CBA from 9 centers. Until August 1997, clinical and angiographic follow-up has completed in 80% and 72%, respectively.Results: Mean number of stent/lesion was 1.5 +/- 0.9 (slotted tube stent 62%) and lesion length 17.2 +/- 10.5 mm. CBA was 100% successful with mean balloon size of 3.25 +/- 0.41 mm (CB/artery ratio of 1.20 +/- 0.22), mean inflation of 3.3 +/- 2.6 times, and mean inflation pressure of 8.2 +/- 2.0 atm. QCA data was as follows.Angiographic restenosis was 29% with a mean follow-up of 142 +/- 77 days and TLR rate was 22%.Conclusion: These results suggest that CBA might be superior to our experience with balloon angioplasty for stent restenosis. Randomized study is necessary to confirm its superiority.