The present study was designed to prospectively test the hypothesis that gene polymorphisms of the renin-angiotensin system are associated with recurrent restenosis after repeated percutaneous transluminal coronary angioplasty. Five hundred and eleven patients after first successful angioplasty were characterized with respect to the angiotensinogen M235T, angiotensin-converting enzyme insertion/deletion and angiotensin II type 1 receptor A1166C gene polymorphisms. In 164 of these patients repeated angioplasty on a restenotic lesion was performed. After repeated angioplasty, 46 patients had recurrent restenosis as defined by a greater than 50% progression of residual stenosis. In the recurrent restenosis group there was a statistically significant higher percentage of patients receiving cholesterol-lowering drugs compared with the group of patients without recurrent restenosis. The two groups of patients did not differ with respect to procedural and angiographic parameters. There were significantly more carriers of the angiotensinogen 235T allele in the recurrent restenosis group than in the control group without recurrent restenosis. No differences between the two groups were found with respect to the other gene polymorphisms investigated. According to the results of a multifactorial analysis of variance, only the 235T allele of the angiotensinogen gene and not cholesterol drug therapy independently affected the increase of stenosis at follow-up angiography. In conclusion, the angiotensinogen 235T allele may be an independent predictor for recurrent restenosis after repeated angioplasty.