[Intracoronary Stenting and Angiographic Results Strut Thickness Effect on Restenosis Outcome (ISAR-STEREO) Trial]

Increased thrombogenicity and smooth muscle cell proliferative response induced by the metal struts compromise the advantages of coronary stenting. The objective of this randomized, multicenter study was to ascertain whether a reduced strut thickness of a stent is associated with improved follow-up angiographic and clinical results.

The study covered 651 patients with stenosis in the native coronary arteries > 2.8 mm in diameter. They were randomly assigned to receive 1 of 2 commercially available stents of comparable design but different thickness: 326 patients to the thin-strut stent (strut thickness of 50 microm) and 325 patients to the thicker-strut stent (strut thickness of 140 microm). The primary end point was the angiographic restenosis (> or = 50% diameter luminal stenosis at follow-up angiography). The secondary end points were the incidence of reinterventions due to restenosis-induced ischemia and the total rate of death and myocardial infarctions at 1 year (a combined end point). The incidence of angiographic restenosis was 15.0% in the thin-strut group and 25.8% in the thick-strut group (relative risk, 0.58; 95% CI, 0.39 to 0.87; p = 0.003). Clinical restenosis was also significantly reduced. Reinterventions were made in 8.6% of the thin-strut patients and in 13.8% of the thick-strut patients (relative risk, 0.62; 95% CI, 0.39 to 0.99; p = 0.03). No difference was observed in the combined 1-year rate of death and myocardial infarction.

The use of a thin-strut device is associated with a significant reduction of angiographic and clinical restenosis after coronary artery stenting. These findings may have relevant implications for the currently most widely used percutaneous coronary intervention.