Cross-sectional Percentage Research Articles

Time-related changes in neointimal tissue coverage of a novel Sirolimus eluting stent: Serial observations with optical coherence tomography.

DES has reduced rates of restenosis compared with BMS but it has been associated with delayed healing and increase of stent thrombosis. The aim of our study was to evaluate the vascular time-related changes following implantation of a new SES coated with an amorphous silicon carbide that allows faster re-endothelisation (Orsiro-Biotronik). This prospective registry enrolled STEMI-patients with multi-vessel disease, thus candidates for a two-step procedure. PCI of the culprit lesion was performed with at least one Orsiro stent that was OCT-analysed during the second-step procedure (deferred to 30,90 and 180-days). 16 of the 95 patients with MVD underwent an OCT evaluation of the study device implanted in the culprit lesion during the second-step staged procedure and were enrolled in the present Registry. A total of 3060-struts were analysed. The percentage of uncovered struts was 19.6% at30-days, 1.3% at90-days and 1.8% at180-days (p<0.001). The percentage of cross section with ≥1 uncovered struts were 51.3% at30-days, 6.5% at90-days and 5.7% at180-days (p<0.001). The percentage of cross sections containing thrombus was 6.2% at30-days while no thrombus was detected both at90 and 180-days. Our data shows that the new Orsiro stent promotes early and persistent strut coverage with low peri-strut thrombus. This pilot OCT evaluation might suggest a low incidence of late adverse events and anticipate safe outcome after early withdrawal of dual antiplatelet therapy.

Efficacy of postdeployment balloon dilatation for current generation stents as assessed by intravascular ultrasound

Adjunctive balloon dilatation strategy has been shown to improve optimal stent deployment. As improvements in current stent designs evolve, less adjunctive balloon dilatation may be needed. However, few data currently exist to support this practice. We evaluated 88 native coronary lesions treated with single stent implantation (Nir, Tristar or S670). Serial intravascular ultrasound was performed after successful stent deployment and again after adjunctive balloon dilatation. To investigate further the precise expansion characteristics of the stents, serial volumetric intravascular ultrasound analyses were performed in 40 patients with automated pullback. After adjunctive balloon dilatation, minimal stent area increased significantly, from 6.4 ± 2.1 to 7.4 ± 2.2 mm 2 (p <0.001). Volumetric analysis showed a corresponding increase in stent volume index (6.6 ± 1.8 to 7.5 ± 2.0 mm 3/mm, p <0.001). In the analysis of cross sections at 0.5-mm axial intervals, the percentage of cross sections, where stent area was ≥80% of the average reference lumen area, increased from 51% to 78% (p <0.001). Similarly, the percentage of cross sections, where stent area was ≥90% of the average reference lumen area, increased from 29% to 56% (p <0.001) with postdilatation. Postdeployment high- pressure balloon dilatation improved minimal stent area and volumetric expansion throughout the stented segment.