Long-term angiographic follow up after successful repeat balloon angioplasty for in-stent restenosis

Background: Coronary stent implantation is associated with improved angiogr aphic short-term and mid-term clinical outcome. However, restenosis rate st ill remains between 20 and 30%. Hypothesis: The purpose of the study, performed as a prospective angiograph ic follow-up to detect restenosis, was to evaluate the immediate and the 6- month angiographic results of repeat balloon angioplasty for in-stent reste nosis. Methods: From April 1996 to September 1997, 335 stenting procedures perform ed in 327 patients underwent prospectively 6-month control angiography. Of the 96 lesions that showed in-stent restenosis (> 50% diameter stenosis) (2 9%), 72 underwent balloon angioplasty. Results: The primary success rate was 100%. Follow-up angiogram at a mean o f 6.9 +/- 2.4 months was obtained in 54 patients. Recurrent restenosis was observed in 24 of the 55 stents (44%). Repeat intervention for diffuse and body location instent restenosis before repeat intervention was associated with significantly higher rates of recurrent restenosis (p<0.001 and p<0.05 , respectively). Of the 19 patients who underwent further balloon angioplas ty (100% success rate), coronary angiography was performed in 18 (95%) at a mean of 83 +/- 2.0 months and showed recurrent restenosis in 12 patients ( 67%). Further repeat intervention for diffuse and severe in-stent restenosi s before the second repeat intervention was associated with significantly h igher rates of further recurrent restenosis (p<0.05 and p<0.005, respective ly). Conclusions: Although balloon angioplasty can be safely, successfully, and repeatedly performed after stent restenosis, it carries a progressively hig h recurrence of angiographic restenosis rate during repeat ti-month follow- ups. The subgroup of patients with diffuse, severe, and/or body location in -stent restenosis proved to be at higher risk of recurrent restenosis.