A three-dimensional intravascular ultrasound comparison between the new zotarolimus-eluting stent (ZoMaxx) and the non-drug-eluting TriMaxx stent.

BACKGROUND: Despite the effectiveness of sirolimus- and paclitaxel-eluting stents in reducing intimal hyperplasia (IH) and the need for repeat revascularization, concerns about their long-term safety have motivated the search for new drug-eluting stents (DES). Recently developed, the ZoMaxx stent combines a sirolimus-analogous agent (zotarolimus), featuring a phosphorycoline polymer and stainless steel and tantalum platform. We sought to assess the efficacy of this new DES in reducing IH. METHODS: A total of 40 patients were treated with the ZoMaxx stent and compared to 50 patients treated with its non-drug-eluting equivalent, the TriMaxx stent. Only single de novo lesions in native coronary vessels greater than or equal to 3.0 mm were enrolled. Serial quantitative coronary angiography and intravascular ultrasound (IVUS) images were obtained at baseline and 6- month follow up. All patients were clinically followed for 1 year. This analysis aimed to compare the percent of IH between the 2 stents. Secondarily, we assessed in-segment late loss, binary restenosis and major adverse cardiac events. RESULTS: Baseline patient and lesion characteristics were comparable between the 2 groups. At follow up, zotarolimus efficiently suppressed neointimal hyperplasia formation with a marked reduction in the percentage of stent obstruction by IVUS (4.6 +/- 3.6% vs. 31.2 +/- 16%; p < 0.0001). Almost 90% of the segments stented with ZoMaxx did not exhibit more than 10% of obstruction. After 1 year, 12 patients treated with the TriMaxx and 2 patients treated with the ZoMaxx presented in-segment binary restenosis (p = 0.03). CONCLUSIONS: In this initial experience, ZoMaxx proved to be clinically safe and superior to its non-drug-coated equivalent in reducing in-stent IH formation and restenosis.

Late incomplete apposition after drug-eluting stent implantation: incidence and potential for adverse clinical outcomes

Aim Late acquired incomplete stent apposition (ISA) has been documented after drug-eluting stent (DES) implantation; However, its clinical consequences of late ISA after implantation sirolimus - (SES) or paclitaxel-eluting stent (PES) in a non-elected population. Methods and Results From our database, we analysed 195 consecutive patients who underwent DES placetement(175 with SES and 20 with PES) into native artery lesions and had serial intravascular ultrasound studies (IVUS) performed at index procedure and after 6-8 months. They were clinically followed for 29 +- 15 mounths (median of 24.3 months, interquartile range 18.1 - 31.6 months. They were clinically followed for a separation of at least one stent strut from the vessel wall in a segment without a side-branch and where the immediate post-implantation IVUS revealed complete apposition of stent struts...

Late incomplete apposition after drug-eluting stent implantation: incidence and potential for adverse clinical outcomes.

AIM: Late-acquired incomplete stent apposition (ISA) has been documented after drug-eluting stent (DES) implantation; however, its clinical role remains controversial. We sought to investigate the incidence and long-term clinical consequences of late ISA after implantation of sirolimus- (SES) or paclitaxel-eluting stent (PES) in a non-selected population. METHODS AND RESULTS: From our database, we analysed 195 consecutive patients who underwent DES placement (175 with SES and 20 with PES) into native artery lesions and had serial intravascular ultrasound studies (IVUS) performed at index procedure and after 6-8 months. They were clinically followed for 29 +/- 15 months (median of 24.3 months, interquartile range 18.1-31.6 months). Late ISA was defined as separation of at least one stent strut from the vessel wall in a segment without a side-branch and where the immediate post-implantation IVUS revealed complete apposition of stent struts. We identified 10 patients (5.1%) with late ISA, three patients after PES, and seven patients after SES implantation. ISA was localized almost exclusively at body of the stents (nine out of 10 cases). Mean ISA volume and length were 44.5 +/- 41.9 mm(3) and 7.4 +/- 11 mm, respectively. There was a marked increase in vessel volume from 416.0 +/- 163.9 mm(3) at baseline to 514.4 +/- 247.9 mm(3) at follow-up (P = 0.001) with no significant change in plaque volume (232.4 +/- 52.7 at baseline and 226.4 +/- 22.3 mm(3) at follow-up, P = 0.3) in patients who presented with late-acquired ISA. During the follow-up period, one patient with SES and one patient with PES who presented late-acquired ISA had late stent thrombosis and acute myocardial infarction. CONCLUSION: Late-acquired ISA was observed in 5.1% of patients after DES implantation and is related to regional vessel positive remodelling. The relationship between late-acquired ISA and long-term adverse outcomes (e.g. stent thrombosis) requires further analysis.