摘要
Background The clinical impact of late incomplete stent apposition(ISA) for drug- eluting stents is unknown. We sought to prospectively investigate the incidence and extent of ISA after the procedure and at 6- month follow- up of paclitaxel- eluting stents in comparison with bare metal stents(BMS) and survey the clinical significance of ISA over a period of 12 months. Methods and Results TAXUS II was a randomized, double- blind study with 536 patients in 2 consecutive cohorts comparing slow- release(SR; 131 patients) and moderate- release(MR; 135 patients) paclitaxel- eluting stents with BMS(270 patients). This intravascular ultrasound(IVUS) substudy included patients who underwent serial IVUS examination after the procedure and at 6 months(BMS, 240 patients; SR, 113; MR, 116). The qualitative and quantitative analyses of ISA were performed by an independent, blinded core laboratory. More than half of the instances of ISA observed after the procedure resolved at 6 months in all groups. No difference in the incidence of late- acquired ISA was observed among the 3 groups(BMS, 5.4% ; SR, 8.0% ; MR, 9.5% ; P=0.306), with a similar ISA volume(BMS, 11.4 mm3; SR, 21.7 mm3; MR, 8.5 mm3; P=0.18). Late- acquired ISA was the result of an increase of vessel area without change in plaque behind the stent. Predictive factors of late- acquired ISA were lesion length, unstable angina, and absence of diabetes. No stent thrombosis occurred in the patients diagnosed with ISA over a period of 12 months. Conclusions The incidence and extent of late- acquired ISA are comparable in paclitaxel- eluting stents and BMS. ISA is a pure IVUS finding without clinical repercussions.
Background The clinical impact of late incomplete stent apposition(ISA) for drug- eluting stents is unknown. We sought to prospectively investigate the incidence and extent of ISA after the procedure and at 6- month follow- up of paclitaxel- eluting stents in comparison with bare metal stents(BMS) and survey the clinical significance of ISA over a period of 12 months. Methods and Results TAXUS II was a randomized, double- blind study with 536 patients in 2 consecutive cohorts comparing slow- release(SR; 131 patients) and moderate- release(MR; 135 patients) paclitaxel- eluting stents with BMS(270 patients). This intravascular ultrasound(IVUS) substudy included patients who underwent serial IVUS examination after the procedure and at 6 months(BMS, 240 patients; SR, 113; MR, 116). The qualitative and quantitative analyses of ISA were performed by an independent, blinded core laboratory. More than half of the instances of ISA observed after the procedure resolved at 6 months in all groups. No difference in the incidence of late- acquired ISA was observed among the 3 groups(BMS, 5.4% ; SR, 8.0% ; MR, 9.5% ; P=0.306), with a similar ISA volume(BMS, 11.4 mm3; SR, 21.7 mm3; MR, 8.5 mm3; P=0.18). Late- acquired ISA was the result of an increase of vessel area without change in plaque behind the stent. Predictive factors of late- acquired ISA were lesion length, unstable angina, and absence of diabetes. No stent thrombosis occurred in the patients diagnosed with ISA over a period of 12 months. Conclusions The incidence and extent of late- acquired ISA are comparable in paclitaxel- eluting stents and BMS. ISA is a pure IVUS finding without clinical repercussions.
