Restenosis rate after successful intracoronary implantation of Palmaz-Schatz stents in 100 patients (92 men, 8 women; mean age 57 +/- 11 years) was quantitatively assessed by angiography performed on average 5.3 +/- 0.3 months after the procedure. Restenosis was defined as a more than 50% decrease in lumen. Data from patients with acute or subacute thrombotic complications were excluded from the analysis. The restenosis rate of the total group was 22%. After placement of only one stent (n = 87) it was 17%, of multiple stents per lesion (n = 13) 54%. Restenosis rate after emergency implantation of a single stent (n = 23) was 17.4%, after elective single stent implantation (n = 64) 17.2%. There was no significant difference regarding treatment of new stenoses (n = 16), and recurrent stenosis (n = 48), namely 12.5% vs 18.8%. The following were risk factors for chronic restenosis after stent implantation: multiple stents (odds ratio [OR] 5.6; 95% confidence interval [CI]: 1.6-19.1); implantation in a small vessel, reference diameter < or = 3.0 mm (OR 6.7, CI 2.4-18.7); and residual stenosis after stent implantation of > 8% (OR 3.1, CI 1.2-8.1).