Clinical presentation and outcome of patients hospitalized for symptomatic in-stent restenosis treated by percutaneous coronary intervention: comparison between drug-eluting stents and bare-metal stents.

Background: In-stent restenosis remains the major limitation of percutaneous coronary intervention (PCI), particularly after bare-metal stent (BMS) implantation. Drug-eluting stents (DES) decrease in-stent restenosis, which is thought to have minimal clinical consequences, but may increase the risk of stent thrombosis and its attendant high mortality rate.

Aims: To assess the clinical consequences of in-stent restenosis, including severity of associated illness and acute and 1-year outcomes and to compare DES and BMS in-stent restenosis.

Methods: Using our prospective PCI registry, we compared data from 1958 consecutive patients hospitalized with BMS in-stent restenosis between January 2000 and April 2003 and all 190 patients with DES in-stent restenosis admitted between April 2003 and September 2006. Risk-adjusted outcomes were calculated using propensity-score matching.

Results: An unstable presentation was noted in 78.1% of 2148 patients. Patients with DES in-stent restenosis presented more often with acute myocardial infarction (4.3% versus 1.6%, p<0.001). At 1 year, mortality for all patients was 5.7% and target-vessel revascularization was 21.5%. After risk adjustment, target-vessel revascularization and target-vessel revascularization-major adverse cardiac events were greater in patients with DES in-stent restenosis (respectively, 27.8% versus 19.7%, p=0.05; 32.5% versus 24.3%, p=0.06).

Conclusion: In-stent restenosis is associated with unstable presentation and a higher 1-year adverse events rate than expected in patients undergoing elective PCI. For an identical level of cardiac risk, it seems that DES in-stent restenosis outcomes are slightly worse than BMS in-stent restenosis outcomes.