Coronary Stent System Research Articles

In vivo and in vitro characterization of poly(styrene‐b‐isobutylene‐b‐styrene) copolymer stent coatings for biostability, vascular compatibility and mechanical integrity

The TAXUS Express 2 Paclitaxel Eluting Coronary Stent System employs a coating consisting of the thermoplastic elastomer, poly(styrene-b-isobutylene-b-styrene; SIBS), selected for its drug-eluting characteristics, vascular compatibility, mechanical properties, and biostability. This study was conducted to evaluate the impact of different SIBS (17-51 mole % styrene) compositions on mechanical properties, chemical stability, and vascular compatibility. Mechanical property (stress-strain measurements) and stability studies were conducted on polymer films with five different styrene contents (17, 24, 32, 39, and 51 mole %). The ultimate tensile strength did not change significantly with composition, but the elongation at break decreased with increased styrene content. A pulsatile fatigue test further confirmed the mechanical stability of SIBS up to 39 mole % styrene. The vascular compatibility of five different SIBS compositions was assessed using SIBS-only coated stents, in the coronary and carotid arteries in a porcine model study. The stability of the vessel wall, rate/degree of endothelialization, inflammation, and thrombus at timepoints from 30 to 180 days were evaluated. The results confirm vascular compatibility over the range of 17-51 mole % styrene.

The GENESIS (Randomized, Multicenter Study of the Pimecrolimus-Eluting and Pimecrolimus/Paclitaxel-Eluting Coronary Stent System in Patients with De Novo Lesions of the Native Coronary Arteries) Trial

The aim of this study was to compare, in a randomized multicenter trial, paclitaxel-eluting stents (CoStar, Conor Medsystems, Menlo Park, California) versus pimecrolimus-eluting stents (Corio, Conor Medsystems) versus stents with dual elution of both drugs (SymBio, Conor Medsystems) in native coronary arteries. The CoStar cobalt-chromium reservoir-based stent platform, eluting paclitaxel in a controlled way via a bioresorbable polymer, reduces restenosis versus its respective bare-metal stent. The reservoir system allows the use of other drugs targeted to different mechanisms involved in the process of vascular restenosis and simultaneous loading of multiple, synergistic drugs. Patients with single de novo lesions were asymmetrically randomized to 1 of the 3 types of stent (1:2:2). Six-month coronary angiography was planned in all. The primary analysis was a noninferiority test for the primary end point of 6-month angiographic in-stent late lumen loss of Corio versus CoStar and SymBio versus CoStar. Secondary end points included binary angiographic restenosis and major adverse clinical events (cardiac death, myocardial infarction, target vessel revascularization). The trial was prematurely suspended after 246 patients were enrolled (planned enrollment: 375 patients): 49 patients received CoStar, 97 received SymBio, and 100 received Corio. In-stent late loss was significantly reduced with CoStar versus either SymBio or Corio (0.58 +/- 0.58 mm vs. 0.96 +/- 0.73 mm and 0.58 +/- 0.58 mm vs. 1.40 +/- 0.67 mm, p < 0.001 for both comparisons). Binary in-stent restenosis rates were, 7.1%, 20%, and 40.9%, respectively (p < 0.001 for both comparisons); 6-month major adverse cardiac event rates were, 2.0%, 14.4%, and 39.0%, respectively (p < 0.001 for both comparisons). Stents eluting pimecrolimus or the dual combination of pimecrolimus and paclitaxel failed to show angiographic noninferiority when compared with paclitaxel-eluting stents. (A Randomized, Multi-Center Study of the Pimecrolimus-Eluting and Pimecrolimus/Paclitaxel-Eluting Coronary Stent Systems; NCT00322569).

A bioabsorbable everolimus-eluting coronary stent system (ABSORB): 2-year outcomes and results from multiple imaging methods

Drug-eluting metallic coronary stents predispose to late stent thrombosis, prevent late lumen vessel enlargement, hinder surgical revascularisation, and impair imaging with multislice CT. We assessed the safety of the bioabsorbable everolimus-eluting stent (BVS). 30 patients with a single de-novo coronary artery lesion were followed up for 2 years clinically and with multiple imaging methods: multislice CT, angiography, intravascular ultrasound, derived morphology parameters (virtual histology, palpography, and echogenicity), and optical coherence tomography (OCT). Clinical data were obtained from 29 of 30 patients. At 2 years, the device was safe with no cardiac deaths, ischaemia-driven target lesion revascularisations, or stent thromboses recorded, and only one myocardial infarction (non-Q wave). 18-month multislice CT (assessed in 25 patients) showed a mean diameter stenosis of 19% (SD 9). At 2-year angiography, the in-stent late loss of 0.48 mm (SD 0.28) and the diameter stenosis of 27% (11) did not differ from the findings at 6 months. The luminal area enlargement on OCT and intravascular ultrasound between 6 months and 2 years was due to a decrease in plaque size without change in vessel size. At 2 years, 34.5% of strut locations presented no discernible features by OCT, confirming decreases in echogenicity and in radiofrequency backscattering; the remaining apparent struts were fully apposed. Additionally, vasomotion occurred at the stented site and adjacent coronary artery in response to vasoactive agents. At 2 years after implantation the stent was bioabsorbed, had vasomotion restored and restenosis prevented, and was clinically safe, suggesting freedom from late thrombosis. Late luminal enlargement due to plaque reduction without vessel remodelling needs confirmation.

First-in-Man 1-Year Clinical Outcomes of the Catania Coronary Stent System With Nanothin Polyzene-F in De Novo Native Coronary Artery Lesions: The ATLANTA (Assessment of The LAtest Non-Thrombogenic Angioplasty stent) Trial

This study sought to assess safety and efficacy of implantation of the Catania Coronary Stent System with Nanothin Polyzene-F (CeloNova BioSciences, Newnan, Georgia) in human coronary arteries with clinical data and comprehensive intracoronary imaging. Novel approaches to modify stents (e.g., bioactive agents, coatings) have been developed to address the limitations of bare-metal and drug-eluting stents (e.g., restenosis, target lesion revascularization [TLR], late thrombosis). This first-in-man study using the Catania stent is a prospective, single center, nonrandomized, single-arm study of 55 patients with symptomatic ischemic heart disease with de novo, obstructive lesions of native coronary arteries. Acute angiographic success was 100%. A core laboratory analyzed quantitative coronary angiography and intravascular ultrasound data immediately after stenting and at 6-month follow-up. Late lumen loss was 0.60 +/- 0.48 mm and the percent neointimal hyperplasia volume was 27.9 +/- 16.1%. In 15 of 55 randomly selected patients, 1,904 cross-sections (19,028 struts) were analyzed at 6 months by optical coherence tomography. Overall, 99.5% of struts were covered. Only 29 of 19,028 struts (0.15%) were malapposed. Binary angiographic restenosis was 6.8%. No death, myocardial infarction, or Academic Research Consortium-defined stent thrombosis was observed at 12 months. The incidence of TLR at 12 months was clinically driven TLR 3.6% (2 of 55) and nonclinically driven TLR 7.3% (4 of 55). This first-in-man showed an excellent early and mid-term safety profile and high-level efficacy of the new Catania stent in the treatment of de novo coronary lesions in a fairly complex population. Polyzene-F coated stents may be an alternative to both bare-metal and drug-eluting stents with reduced late loss, restenosis, and the TLR without long-term dual antiplatelet therapy.

Circulation: Clinical Summaries

<i>Circulation:</i> Clinical Summaries

Randomized Comparison of Everolimus-Eluting and Paclitaxel-Eluting Stents

In the prospective randomized Clinical Evaluation of the Xience V Everolimus Eluting Coronary Stent System in the Treatment of Patients with de novo Native Coronary Artery Lesions (SPIRIT) III trial, an everolimus-eluting stent (EES) compared with a widely used paclitaxel-eluting stent (PES) resulted in a statistically significant reduction in angiographic in-segment late loss at 8 months and noninferior rates of target vessel failure (cardiac death, myocardial infarction, or target vessel revascularization) at 1 year. The safety and efficacy of EES after 1 year have not been reported. A total of 1002 patients with up to 2 de novo native coronary artery lesions (reference vessel diameter, 2.5 to 3.75 mm; lesion length < or =28 mm) were randomized 2:1 to EES versus PES. Antiplatelet therapy consisted of aspirin indefinitely and a thienopyridine for > or =6 months. Between 1 and 2 years, patients treated with EES compared with PES tended to have fewer episodes of protocol-defined stent thrombosis (0.2% versus 1.0%; P=0.10) and myocardial infarctions (0.5% versus 1.7%; P=0.12), with similar rates of cardiac death (0.3% versus 0.3%; P=1.0) and target vessel revascularization (2.9% versus 3.0%; P=1.0). As a result, at the completion of the 2-year follow-up, treatment with EES compared with PES resulted in a significant 32% reduction in target vessel failure (10.7% versus 15.4%; hazard ratio, 0.68; 95% confidence interval, 0.48 to 0.98; P=0.04) and a 45% reduction in major adverse cardiac events (cardiac death, myocardial infarction, or target lesion revascularization; 7.3% versus 12.8%; hazard ratio, 0.55; 95% confidence interval, 0.36 to 0.83; P=0.004). Among the 360 patients who discontinued clopidogrel or ticlopidine after 6 months, stent thrombosis subsequently developed in 0.4% of EES patients versus 2.6% of PES patients (P=0.10). Patients treated with EES rather than PES experienced significantly improved event-free survival at a 2-year follow-up in the SPIRIT III trial, with continued divergence of the hazard curves for target vessel failure and major adverse cardiac events between 1 and 2 years evident. The encouraging trends toward fewer stent thrombosis episodes after 6 months in EES-treated patients who discontinued a thienopyridine and after 1 year in all patients treated with EES rather than PES deserve further study.

The effect of a layer-by-layer chitosan–heparin coating on the endothelialization and coagulation properties of a coronary stent system

A biomacromolecular layer-by-layer coating process of chitosan/heparin onto a coronary stent is designed for the acceleration of the re-endothelialization and healing process after coronary stent deployment. The results of in vitro culturing of porcine iliac artery endothelial cells as well as the measurements of the APTT, PT and TT supported the rationale that the combination of chitosan and heparin could bring both endothelial cell compatibility and haemocompatibility to the stent surface. A porcine coronary injury model and arteriovenous shunt model were used for the further evaluation of the application of this kind of surface-modified stainless steel stent in vivo. The final results proved that this facile coating approach could significantly promote re-endothelialization and was safer compared with bare metal stents for its much improved anticoagulation property.

Late Stent Recoil of the Bioabsorbable Everolimus-Eluting Coronary Stent and its Relationship With Plaque Morphology

This study sought to evaluate late recoil of a novel bioabsorbable everolimus-eluting coronary stent (BVS), which is composed of a poly-L-lactic acid backbone, coated with a bioabsorbable polymer containing everolimus. Little is known about the mechanical behavior of bioabsorbable polymer stents after deployment in diseased human coronary arteries. The study population consisted of 16 patients, who were treated with elective BVS implantation for single de novo native coronary artery lesions and were followed at 6 months. All patients underwent an intravascular ultrasound examination at post-procedure and follow-up. A total of 484 paired cross-sectional areas (CSAs) were acquired and analyzed. Late absolute stent recoil was defined as stent area at post-procedure (X) - stent area at follow-up (Y). Late percent stent recoil was defined as (X - Y)/X x 100. In each CSA, plaque morphology was assessed qualitatively and classified as calcific, fibronecrotic, or fibrocellular plaque. Late absolute and percent recoil of the BVS was 0.65 +/- 1.71 mm(2) (95% confidence interval [CI]: 0.49 to 0.80 mm(2)) and 7.60 +/- 23.3% (95% CI: 5.52% to 9.68%). Calcified plaques resulted in significantly less late recoil (0.20 +/- 1.54 mm(2) and 1.97 +/- 22.2%) than fibronecrotic plaques (1.03 +/- 2.12 mm(2) and 12.4 +/- 28.0%, p = 0.001 and p = 0.001, respectively) or fibrocellular plaque (0.74 +/- 1.48 mm(2) and 8.90 +/- 19.8%, p = 0.001 and p = 0.001, respectively). The BVS shrank in size during the follow-up period. The lesion morphology of stented segments might affect the degree of late recoil of the BVS. (ABSORB Everolimus Eluting Coronary Stent System First in Man Clinical Investigation; NCT00300131).

A Randomized, Controlled, Multicenter Trial to Evaluate the Safety and Efficacy of Zotarolimus- Versus Paclitaxel-Eluting Stents in De Novo Occlusive Lesions in Coronary Arteries: The ZoMaxx I Trial

A novel zotarolimus-eluting coronary stent system (ZoMaxx, Abbott Laboratories, Abbott Park, Illinois) was compared with a paclitaxel-eluting coronary stent (Taxus Express2) in a randomized trial of percutaneous intervention for de novo coronary artery stenosis. The primary end point was defined as noninferiority of in-segment late lumen loss after 9 months. The ZoMaxx stent system elutes 10 microg/mm zotarolimus using a phosphorylcholine polymer loaded onto a novel stainless steel stent platform containing a 0.0007-inch inner layer of tantalum. Twenty-nine investigative sites in Europe, Australia, and New Zealand enrolled 401 patients, 396 of whom received a study stent. After 9 months, late lumen loss was significantly greater in the ZoMaxx group (in-stent 0.67 +/- 0.57 mm vs. 0.45 +/- 0.48 mm; p < 0.001; in-segment 0.43 +/- 0.60 mm vs. 0.25 +/- 0. 45 mm; p = 0.003), resulting in significantly higher rates of >50% angiographic restenosis (in-stent 12.9% vs. 5.7%; p = 0.03; in-segment 16.5% vs. 6.9%; p = 0.007). The upper bound of the 95% confidence interval on the difference in in-segment late lumen loss between the 2 treatment groups (0.27 mm) exceeded the 0.25 mm value pre-specified for noninferiority. There were no significant differences between ZoMaxx and Taxus-treated groups with respect to target lesion revascularization (8.0% vs. 4.1%; p = 0.14), major adverse cardiac events (12.6% vs. 9.6%; p = 0.43), or stent thrombosis (0.5% in both groups). After 9 months, the ZoMaxx stent showed less neointimal inhibition than the Taxus stent, as shown by higher in-stent late loss and restenosis by qualitative coronary angiography.

Systemic exposure of everolimus after stent implantation: A pharmacokinetic study

We evaluated the pharmacokinetics of the eluted everolimus by assessing systemic drug release and distribution of everolimus-eluting stents. Drugs eluted by a coronary stent might cause adverse events such as tumors, infections, or noncardiac death. The systemic exposure of the drugs is unknown because there are only limited data about pharmacokinetics of drug-eluting stents in humans. Venous blood samples in a subset of 39 patients were drawn just before implantation of the first stent (baseline, 0-minute time point) and at 10 and 30 minutes and 1, 2, 4, 6, 12, 24, 36, 48, 72, 168, and 720 hours (30 days) after completion of implantation of the last stent. Whole blood concentrations of everolimus were determined using a sensitive validated high-performance liquid chromatography mass spectrometry/mass spectrometry method. The total dose of everolimus received by the patients ranged from 53 to 588 microg. The last time point up to which whole blood concentrations could be quantified ranged per patient from 4 to 720 hours after implantation of the last stent. Across all dose levels, individual T(max) values ranged from 0.13 and 2.17 hours; individual C(max) ranged from 0.14 to 2.79 ng/mL. This study confirms the limited exposure to the systemic circulation of the eluted drug with the use of the XIENCE V Everolimus-Eluting Coronary Stent System (Abbott Vascular, Santa Clara, CA). Therefore, a systemic cause of adverse events is unlikely.

Xience V Spirit Women Clinical Trial: Characterization of the Female Population Undergoing Stent Implantation

The XIENCE V SPIRIT WOMEN study will focus on specific aspects of women's health in relation to coronary artery disease, such as menopausal status, use of hormonal contraceptives or their surrogates, and the referral path and symptoms at presentation. The study is a prospective, open-label, single-arm, multicenter study designed to evaluate the performance of the XIENCE V Everolimus-Eluting Coronary Stent System in the treatment of female patients with coronary artery lesions. It also includes a prospective, single-blind, double-arm, randomized, multicenter substudy, in which patients will be randomized in a 2:1 ratio between the XIENCE V stent and the CYPHER Plus. In total, approximately 2000 female patients, derived from the general interventional cardiology population, will be enrolled from up to 130 sites outside of the USA.

Overview of the 2007 Food and Drug Administration Circulatory System Devices Panel Meeting on the Endeavor Zotarolimus-Eluting Coronary Stent

Initial trials comparing stenting with balloon angioplasty demonstrated improved angiographic and clinical outcomes with the former.1–3 The main clinical problem with bare metal stents (BMS) became the development of in-stent restenosis.4–6 Early data suggested that drug-eluting stents (DES) could mitigate, if not abolish, this problem.7–9 Since the approval of DES, these devices have become the predominant stents used in percutaneous coronary interventions, regardless of indication. As of September 2007, the Cypher sirolimus-eluting stent (SES) (Cordis Johnson & Johnson, Miami Lakes, Fla) had been deployed in >3 million patients worldwide,10 and the millionth Taxus paclitaxel-eluting stent (PES) (Boston Scientific, Natick, Mass) was implanted as of January 2005.11 Over the past 2 years, numerous reports of very late stent thrombosis (ST) with first-generation DES have surfaced. This highly morbid complication and data suggesting that death and myocardial infarction (MI) may be more common with DES12,13 have altered the focus of trials and registries working to determine optimal DES use. There is a hope that second-generation DES will be less prone to ST as a result of differences in drug, stent design, and polymer. Medtronic, Inc (Minneapolis, Minn) presented safety and efficacy data to a public meeting of the US Food and Drug Administration (FDA) Circulatory System Devices Panel (CSDP) in October 2007 on its Endeavor zotarolimus-eluting stent (ZES), seeking approval for the indication of treating de novo native coronary lesions ≤27 mm with reference vessel diameters of 2.5 to 3.5 mm. The FDA asked the CSDP to determine whether the data presented demonstrated a reasonable level of safety and effectiveness, with clinical benefits clearly outweighing short- and long-term risks of ZES use. Important efficacy end points included ischemia-driven target lesion revascularization (TLR) or target vessel revascularization (TVR); safety end points included death, MI, and ST. The …

A bioabsorbable everolimus-eluting coronary stent system for patients with single de-novo coronary artery lesions (ABSORB): a prospective open-label trial

A fully bioabsorbable drug-eluting coronary stent that scaffolds the vessel wall when needed and then disappears once the acute recoil and constrictive remodelling processes have subsided has theoretical advantages. The bioasorbable everolimus-eluting stent (BVS) has a backbone of poly-L-lactic acid that provides the support and a coating of poly-D,L-lactic acid that contains and controls the release of the antiproliferative agent everolimus. We assessed the feasibility and safety of this BVS stent. In this prospective, open-label study we enrolled 30 patients who had either stable, unstable, or silent ischaemia and a single de-novo lesion that was suitable for treatment with a single 3.0 x 12 mm or 3.0 x 18 mm stent. Patients were enrolled from four academic hospitals in Auckland, Rotterdam, Krakow, and Skejby. The composite endpoint was cardiac death, myocardial infarction, and ischaemia-driven target lesion revascularisation. Angiographic endpoints were available for 26 patients and intravascular-ultrasound endpoints for 24 patients. Clinical endpoints were assessed in all 30 patients at 6 and 12 months. In a subset of 13 patients, optical coherence tomography was undertaken at baseline and follow-up. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00300131. Procedural success was 100% (30/30 patients), and device success 94% (29/31 attempts at implantation of the stent). At 1 year, the rate of major adverse cardiac events was 3.3%, with only one patient having a non-Q wave myocardial infarction and no target lesion revascularisations. No late stent thromboses were recorded. At 6-month follow-up, the angiographic in-stent late loss was 0.44 (0.35) mm and was mainly due to a mild reduction of the stent area (-11.8%) as measured by intravascular ultrasound. The neointimal area was small (0.30 [SD 0.44] mm2), with a minimal area obstruction of 5.5%. This study shows the feasibility of implantation of the bioabsorbable everolimus-eluting stent, with an acceptable in-stent late loss, minimal intrastent neointimal hyperplasia, and a low stent area obstruction. Abbott Vascular.

Differentiated analysis of an everolimus-eluting stent and a paclitaxel-eluting stent among higher risk subgroups for restenosis: results from the SPIRIT II trial

Restenosis is higher among certain subpopulations when subjected to percutaneous coronary interventions even when using drug-eluting stents. The randomised SPIRIT II trial demonstrated the superiority of the XIENCE V Everolimus Eluting Coronary Stent System over the TAXUS Paclitaxel-Eluting Stent System in terms of in-stent late loss at six months among 300 patients treated for de novo native coronary artery lesions. In this post-hoc analysis of SPIRIT II we focused on six-month angiographic outcomes of diabetic patients (n=69), left anterior descending arteries (n=149), long lesions >20 mm (n=43), small vessels <3.0 mm (n=209) and type B2 and C lesions (n=233). In-stent late loss was consistently less among all subgroups when treated by everolimus-eluting stents compared to paclitaxel-eluting stents: diabetics 0.15+/-0.26 mm versus 0.39+/-0.34 mm, p=0.006; LAD 0.12+/-0.23 mm versus 0.44+/-0.37 mm, p<0.001; long lesions 0.13+/-0.26 mm versus 0.43+/-0.46 mm, p=0.070; small vessels 0.17+/-0.28 mm versus 0.37+/-0.39 mm, p<0.001; B2/C lesions 0.12+/-0.31 mm versus 0.36+/-0.36 mm, p<0.001. The everolimus-eluting stent remained superior in terms of in-stent late loss in a variety of higher risk populations for restenosis compared to the paclitaxel-eluting stent. These analyses were consistent with the in-stent late loss results of the overall SPIRIT II trial population.

Abbott has received reimbursement approval in France for its everolimus-eluting coronary stent system

Abbott has received reimbursement approval in France for its everolimus-eluting coronary stent system

Clinical and angiographic results of percutaneous coronary revascularization using a trilayer stainless steel‐tantalum‐stainless steel phosphorylcholine‐coated stent: The TriMaxx trial

The TriMaxx coronary stent system includes a novel trilayer metal stent having two outer layers of 316L stainless steel and with an inner 0.0007 inches layer of tantalum. This enables creation of a maximally flexible and thin device (0.0029 inches) while still maintaining the requisite strength and radiopacity for effective implantation. The objective of this multi-center, single-arm prospective clinical trial was to assess the safety and performance of the TriMaxx stent for the treatment of single de novo coronary artery lesions. One hundred patients with ischemic coronary occlusive disease because of single de novo obstructive lesions of native coronary arteries were treated with 3 x 15 or 3 x 18 mm TriMaxx stents in four hospitals in Brazil and Germany between May of 2004 and September of 2005. An independent core laboratory analyzed the quantitative coronary angiography (QCA) results immediately after stent implantation, and after six months. The lesion, procedure, and device-deployment success rates were 100, 99, and 100%, respectively. Eighty-eight patients underwent follow-up angiography at 6 +/- 1 months. After six months, 13 (13%) of patients had sustained major adverse cardiac events, including 9.0% that required target lesion revascularization (TLR). The follow-up angiographic studies revealed a binary in-stent restenosis rate of 25% with in-stent late lumen loss of 0.94 +/- 0.57 mm. These results demonstrate that the TriMaxx stent can be safely deployed for the treatment of single de novo coronary occlusive lesions with six-month clinical and angiographic results rates comparable to historical results using other bare metal stents.

One year clinical follow-up of the XIENCE V Everolimus-eluting stent system in the treatment of patients with de novo native coronary artery lesions: the SPIRIT II study

The SPIRIT II study randomised 300 patients in a ratio of 3:1 to receive either a XIENCE V or a TAXUS stent. The six month clinical and angiographic results have previously been reported. This paper presents the clinical follow-up of these patients to one year. As a continuation in the assessment of the safety and performance of the XIENCE V Everolimus-Eluting Coronary Stent System (EECSS) enrolled patients were requested to return for clinical follow-up one year following the procedure to assess the occurrence of ischaemia driven major adverse cardiac events (MACE).Of the 300 patients recruited at 28 sites in Europe, New Zealand and India, 223 were randomised to receive an EECSS stent and 77 a TAXUS paclitaxel eluting coronary stent system (PECSS). One-year clinical follow-up was obtained in 220 of the 223 patients in the EECSS group (98.7%) with one withdrawal prior to 180 days and two non-cardiac deaths (pulmonary malignancy and pneumonia) between six and 12 months, and in 76 of 77 (98.7%) PECSS group of patients (one patient had a missed 270-day and 1-year visit). Between six and 12 months there were no new occurrences of late stent thrombotic events in either group. There were no additional MACE events in the EECSS compared to, two, both ischaemia driven target lesion revascularisations (TLR) in the PECSS group. The clinical safety of the XIENCE V EECSS stent observed at six months was sustained at one year. There were no additional thrombotic or MACE events in the EECSS group. Although not a primary endpoint, there was a significant difference in MACE favouring the EECSS compared to PECSS (2.7% versus 9.2%, P=0.04).

Coronary Stent System Recalled

Biomedical Safety & Standards 37(19):p 150-151, November 1, 2007. | DOI: 10.1097/01.BMSAS.0000297175.82621.b3

Comparison of vascular response to zotarolimus-eluting stent versus sirolimus-eluting stent: Intravascular ultrasound results from ENDEAVOR III

The purpose of this study was to investigate the vascular response of zotarolimus-eluting stent (ZES) and sirolimus-eluting stent (SES) using serial intravascular ultrasound (IVUS). Data were obtained from the Endeavor Drug-Eluting Coronary Stent System Versus the Center Siromlimus-Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions (ENDEAVOR) III trial, a randomized study comparing ZES and SES for the treatment of de novo native coronary artery lesions. Serial (baseline and 8-month follow-up) IVUS was available in 258 patients (190 ZES, 68 SES). At 8 months, ZES had greater percentage of neointimal volume index (ZES 1.1 +/- 0.8 mm3/mm vs SES 0.2 +/- 0.1 mm3/mm, P < .01), resulting in smaller lumen volume index (6.0 +/- 2.0 mm3/mm vs 7.0 +/- 2.1 mm3/mm, P < .05). Zotarolimus-eluting stents showed larger IVUS-detectable neointimal coverage over stent surface (50.2% vs 10.5%, P < .01) and greater mean neointimal thickness (0.19 +/- 0.07 mm vs 0.10 +/- 0.06 mm, P < .01). Zotarolimus-eluting stents had a significantly lower incidence of late-acquired incomplete stent apposition. Zotarolimus-eluting stent is associated with a significantly greater amount of neointimal hyperplasia compared with SES. This amount of hyperplasia in ZES is distributed throughout the stent at 8-month follow-up.

Two-year results of a durable polymer everolimus-eluting stent in de novo coronary artery stenosis (The SPIRIT FIRST Trial)

The successful use of everolimus on a durable polymer was earlier reported with 6 and 12 months data from this first-in-man study. This reports the long-term follow-up of the XIENCE V everolimus-eluting stent. This prospective, single-blinded, randomised, multicentre clinical trial evaluated the safety and efficacy of the XIENCE V everolimus-eluting coronary stent system versus an identical bare metal stent in the treatment of patients with a single de novo coronary artery stenosis of >/=50% and <100% and a vessel diameter of 3.0 mm as assessed by on-line quantitative coronary angiography that could be covered by a single 18 mm stent.Sixty patients were randomised and at two-year follow-up, clinical data was available in 96% and 97% of patients in the everolimus and control arm, respectively. Four patients were excluded due to protocol violations and two patients withdrew consent.In the everolimus arm no additional death, myocardial infarction, clinically driven TLR, or TVR events were observed between one and two-year follow-up. The 2-year hierarchical MACE rate for the everolimus arm remained 15.4% (4/26). In the control group, two patients had a clinically driven target lesion revascularisation. MACE rate increased from 21.4% (6/28) to 25.0% (7/28) in the control group. This report confirms and extends the safety and efficacy results of the durable polymer XIENCE V everolimus-eluting stent up to two years as compared to identical bare metal stents.