RESTENOSIS AFTER PLACEMENT OF PALMAZ-SCHATZ STENTS IN NATIVE CORONARY-ARTERIES - INITIAL RESULTS OF A MULTICENTER EXPERIENCE

Background. Several metallic intracoronary stents axe currently undergoing preliminary evaluation to ascertain potential benefit as means to reduce the 30-40% incidence of restenosis after balloon angioplasty. Methods and Results. To determine the incidence and correlates of restenosis after placement of Palmaz-Schatz stents in native coronary arteries in the first group of patients selected for this clinical and quantitative angiographic data from 206 consecutive patients (221 stenoses) with successful stent placement (diameter stenosis <50%) were analyzed. Six patients (2.9%) had thrombosis-mediated stent closure within 1 month after stent placement and were excluded from long-term angiographic follow-up. One hundred eighty-one (91%) of the remaining 200 patients had angiography at 5.8 +/- 2.1 months. Patients with and without follow-up did not differ in any baseline characteristic; in particular history of restenosis at the site stented (73% versus 65%), placement of multiple overlapping stents (17% versus 20%), and mean poststent diameter stenosis (16 +/- 12% versus 14 +/- 12%). The overall incidence of restenosis (diameter stenosis greater-than-or-equal-to 50% at follow-up) in this group at high risk for restenosis was 36% (95% confidence interval, 29-43%) on a per-stenosis basis. The incidence of restenosis when a single stent was placed was 30% (95% confidence interval, 23-37%). Risk was dependent upon a history of restenosis (present versus absent 36% versus 16%, p=0.02) and upon whether or not a poststent stenosis less-than-or-equal-to 0% was achieved (6% versus 33%, p=0.02). When multiple overlapping stents were placed, restenosis occurred at 64% of sites, and placement of multiple stents was discouraged during the later phases of this study as these results became apparent. Conclusions. Although multiple stents appear to yield a poor long-term result, placement of single stents may offer a benefit compared with standard coronary angioplasty, particularly if an excellent angiographic result can be obtained in patients without prior restenosis. Further randomized trials in such patients are needed.