Impact of positive peri-stent vascular remodeling after sirolimus-eluting and paclitaxel-eluting stent implantation on 5-year clinical outcomes: Intravascular ultrasound analysis from the poststent optimal stent Expansion Trial multicenter randomized Trial

Background: Positive peri-stent vascular remodeling (PPVR) after drug-eluting stent (DES) implantation is an important mechanism of late-acquired stent malapposition (LASM). Methods and Results: A total of 226 patients (sirolimus-eluting stent [SES], n=105; paclitaxel-eluting stent [PES], n=121) from the Poststent Optimal Stent Expansion Trial who underwent a post-intervention and 9-month follow-up intravascular ultrasound were followed clinically for 5 years. PPVR was arbitrarily defined as a >10% increase in the external elastic membrane volume index at follow-up. PPVR and LASM occurred more frequently with SESs than with PESs. The 5-year rate of major adverse cardiac events was lower with SES than with PES (10.7% vs. 23.2%, P=0.002). The late and very late stent thrombosis (ST) rate was similar between the 2 DES types, but it was higher in patients with PPVR than in those without PPVR (8.8% vs. 1.3%, P=0.009) regardless of the DES type. Early discontinuation (<1 year) of dual antiplatelet therapy (DAPT; hazard ratio [HR], 24.14; 95% confidence interval [CI]: 4.90-118.87; P<0.001), PPVR (HR, 14.94; 95%CI: 1.85-120.46; P=0.011), LASM (HR, 8.01; 95%CI: 1.93-33.16; P=0.004), and stent length (HR, 1.14; 95%CI: 0.98-1.32 per mm; P=0.078) were associated with increased risk of late and very late ST. Conclusions: PPVR and LASM development after DES implantation, along with early discontinuation of DAPT and longer stent length, are important risk factors of late and very late ST.