One-year performance of thin-strut cobalt chromium sirolimus-eluting stent versus thicker strut stainless steel biolimus-eluting coronary stent: a propensity-matched analysis of two international all-comers registries.

OBJECTIVES: Recent improvements in coronary stent design have focussed on thinner struts, different alloys and architecture, more biocompatible polymers, and shorter drug absorption times. This study evaluates safety and efficacy of a newer generation thin-strut cobalt chromium sirolimus-eluting coronary stent (SES, Ultimaster) in comparison with a second-generation thicker strut stainless steel biolimus-eluting stent (BES, Nobori) in percutaneous coronary intervention (PCI) practice. METHODS: A propensity score analysis was performed to adjust for differences in baseline characteristics of 8137 SES patients and 2738 BES patients of two PCI registries (e-Ultimaster and NOBORI 2). An independent clinical event committee adjudicated all endpoint-related adverse events. RESULTS: The use of SES, as compared with BES was associated with a significantly lower rate of myocardial infarction (MI) (1.2% vs 2.2%; P = 0.0006) and target vessel-related MI (1.1% vs 1.8%; P = 0.002) at 1 year. One-year composite endpoints of all predefined endpoints were lower in patients undergoing SES implantation (target lesion failure: 3.2% vs 4.1%; P = 0.03, target vessel failure: 3.7% vs 5.0%; P = 0.003, patient-oriented composite endpoint 5.7% vs 6.8%; P = 0.03). No significant differences between SES and BES were observed in all-cause death (2.0% vs 1.6%; P = 0.19), cardiac death (1.2% vs 1.2%; P = 0.76) or stent thrombosis (0.6% vs 0.8%; P = 0.43). CONCLUSIONS: These findings suggest an improved clinical safety and efficacy of a newer generation thin-strut SES as compared with a second-generation thicker strut BES.

New-generation drug-eluting coronary stents in octogenarians: Patient-level pooled analysis from the TWENTE I-IV trials.

BACKGROUND: Patients aged ≥80 years are often treated with new-generation drug-eluting stents (DES), but data from randomized studies are scarce owing to underrepresentation in most trials. We assessed 1-year clinical outcome of octogenarians treated with new-generation DES versus younger patients. METHODS: We pooled patient-level data of 9,204 participants in the TWENTE, DUTCH PEERS, BIO-RESORT, and BIONYX (TWENTE I-IV) randomized trials. The main clinical end point was target vessel failure (TVF), a composite of cardiac death, target vessel-related myocardial infarction (MI), or clinically indicated target vessel revascularization. RESULTS: The 671 octogenarian trial participants had significantly more comorbidities. TVF was higher in octogenarians than in 8,533 patients <80 years (7.3% vs 5.3%, hazard ratio [HR]: 1.36, 95% CI: 1.0-1.83, P = .04). The cardiac death rate was higher in octogenarians (3.9% vs 0.8%, P < .001). There was no significant between-group difference in target vessel MI (2.3% vs 2.3%, P = .88) and repeat target vessel revascularization (1.9% vs 2.8%, P = .16). In multivariate analyses, age ≥ 80 years showed no independent association with TVF (adjusted HR: 1.04, 95% CI: 0.76-1.42), whereas the risk of cardiac death remained higher in octogenarians (adjusted HR: 3.38, 95% CI: 2.07-5.52, P < .001). In 6,002 trial participants, in whom data on major bleeding were recorded, octogenarians (n = 459) showed a higher major bleeding risk (5.9% vs 1.9%; HR: 3.08, 95% CI: 2.01-4.74, P < .001). CONCLUSIONS: Octogenarian participants in 4 large-scale randomized DES trials had more comorbidities and a higher incidence of the main end point TVF. Cardiac mortality was higher in octogenarians, whereas there was no increase in MI or target vessel revascularization rates. Treatment of octogenarian patients with new-generation DES appears to be safe and effective.

The Potential Effects of New Stent Platforms for Coronary Revascularization in Patients With Diabetes.

Coronary artery disease in patients with diabetes mellitus (DM) is characterized by extensive atherosclerosis, longer lesions, and diffuse distal disease. Consequently, these patients have worse outcomes after coronary revascularization, regardless of the modality used. Traditionally, coronary artery bypass grafting (CABG) has been regarded as more effective than percutaneous coronary intervention (PCI) in patients with DM, likely because of more complete revascularization and protection against disease progression in the bypass segment. Revascularization with balloon angioplasty, bare-metal stents, and first-generation drug-eluting stents have all been shown to be inferior to CABG in patients with DM. Current professional society guidelines reflect these findings, strongly recommending CABG over PCI in this setting. Newer stent platforms, however, have challenged this notion. The use of thinner struts, biocompatible polymer coating, and newer antiproliferative agents have improved the rates of cardiovascular events in patients with DM revascularized percutaneously. Since the publication of current guidelines, new studies suggested acceptable outcomes in patients with DM revascularized with second-generation drug-eluting stents, even though these conclusions are drawn from small subgroup analyses or nonrandomized studies. Robust registry data suggest similar mortality with lower rates of stroke after PCI compared with surgery, at the expense of increased rates of repeat revascularization. If complete revascularization can be achieved, similar rates of myocardial infarction are also observed. Therefore, contemporary revascularization in patients with DM with multivessel coronary artery disease should involve a multidisciplinary approach, in which interventional cardiologists and cardiac surgeons involve their patients to individualize treatment choices, and balance the risks and effectiveness of each modality.

Stent Coating Integrity of Durable and Biodegradable Coated Drug Eluting Stents.

BACKGROUND: Coatings consisting of a polymer and drug are widely used in drug-eluting stents (DES) and are essential in providing programmable drug release kinetics. Among other factors, stent coating technologies can influence blood compatibility, affect acute and sub-acute healing, and potentially trigger a chronic inflammatory response. OBJECTIVE: The aim of this study was to investigate the short-term (7 and 28 days) and long-term (90 and 180 days) coating integrity of the Xience Prime Everolimus-Eluting Stent (EES), Resolute Zotarolimus-Eluting Stent (ZES), Taxus Paclitaxel-Eluting Stent (PES), and Nobori Biolimus A9-Eluting Stent (BES) in a rabbit ilio-femoral stent model. METHODS AND RESULTS: Stented arteries (n = 48) were harvested and the tissue surrounding the implanted stents digested away with an enzymatic solution. Results demonstrated that the majority of struts of EES were without any coating defects with a few struts showing minor defects. Similarly, for the ZES, most of the struts were without coating defects at all time points except at 180 days. The majority of PES demonstrated mostly webbing and uneven coating. In the BES group, the majority of strut coating showed polymer cracking. CONCLUSION: Overall, the EES and ZES had fewer coating defects than the PES and BES. Coating defects, however increase over time for the ZES, whereas the percent of coating irregularities remained constant for the EES. These results provide, for the first time, a comparison of the long-term durability of these drug-eluting stent coatings in vivo.

Early Phase Arterial Reaction Following Drug-Eluting and Bare-Metal Stent Implantation in Patients With ST-Segment Elevation Myocardial Infarction.

The early phase arterial reaction after implantation of second-generation drug-eluting stents (2nd DES) and baremetal stents (BMS) in patients with ST-segment elevation myocardial infarction (STEMI) remains unclear.The MECHANISM pilot study is a multi-center prospective registry that enrolled 24 STEMI patients (from 11 centers) who had undergone implantation of everolimus-eluting (n = 6), biolimus A9-eluting (n = 6) or zotarolimus-eluting stents (n = 6), or BMS (n = 6). Scheduled optical coherence tomography (OCT) was performed 2 weeks after implantation, and images were independently analyzed at a core laboratory in a blinded fashion. Intra-stent thrombus was quantitatively analyzed in terms of the maximal area and the percentage of cross-sections with thrombus (the numbers of cross-section with thrombus × 100 divided by total number of cross-sections within the stented segment). More than 90% of struts were already covered 2 weeks after the index procedure, regardless of the stent type. There were no differences in stent diameter, minimal lumen diameter, minimal lumen area, neointimal thickness, or the frequencies of malapposed and uncovered struts among the 4 groups. The quantity of intra-stent thrombus also did not differ among the 4 groups.The results of this pilot study suggest that the 2-week vascular responses seem to be similar among 2nd DES and BMS in STEMI patients. Considering the possible advantage of 2nd DES in the prevention of restenosis, 2nd DES are a feasible option for the treatment of patients with STEMI.

Characterization of patients with angioscopically-detected in-stent mural thrombi ­ genetics of clopidogrel responsiveness and generations of drug-eluting stents.

BACKGROUND: The loss-of-function genotype of cytochrome P450 2C19 (CYP2C19) has been proposed as a risk factor for stent thrombosis in patients with drug-eluting stent implantation. The aim of this study was to clarify the clinical features of patients with angioscopically-detected in-stent mural thrombi (ISMT). METHODS AND RESULTS: Enrolled were 100 stented segments in 55 patients with stable angina (20 bare-metal stents; 39 Cypher sirolimus-eluting stents [SES]; 26 Endeavor zotarolimus-eluting stents [ZES]; 13 Xience V everolimus-eluting stents; and 2 Nobori biolimus-eluting stents). Dual antiplatelet therapy (100 mg aspirin+75 mg clopidogrel once daily) had been continued since stenting. A poor metabolizer (PM) of clopidogrel was defined as a homozygote of CYP2C19 loss-of-function alleles. Coronary angioscopy revealed ISMT in 6 patients (5 SES, 1 ZES). Between the ISMT group and control group (n=49), there were no significant differences with regards to the VerifyNow P2Y12platelet function assay or in-stent endothelial coverage grade. Exact logistic regression analyses with stepwise forward selection at a significance level of 0.10 were performed to reveal predictive variables for ISMT (respectively: odds ratio, 95% confidence interval, P value: CYP2C19 PM genotype (3.28, 0.88-24.80, 0.09), SES implantation (3.37, 0.90-28.09, 0.08), and presence of yellow plaque (3.69, 1.14-25.70, 0.02). CONCLUSIONS: Patients with ISMT were characterized by SES implantation, poor clopidogrel metabolism, and in-stent yellow plaque.

Colonic stents: the modern treatment of colonic obstruction.

Colonic stents traditionally have been used for the management of colorectal cancer, either as a palliative treatment or as a bridge to surgery. More recently, colonic stents have also been advocated as part of the therapy of benign strictures. A number of colonic stents are available worldwide, four of which are made in the USA. These stents are classified as covered or uncovered, with similar clinical applications. Technical and clinical success rates are similar among these different stents, as well as the rate of complications, which mainly consist of obstruction and migration. The deployment systems utilize fluoroscopy, endoscopy, or both. More recently, stents became available that are deployed "through the scope" (TTS) making the procedure faster. However, this advance does not exclude the use of fluoroscopy, particularly in those cases where the direct visualization of the proximal end of the stricture is absent. The increasing experience in the management of colorectal cancer with colonic stents decreases the morbidity and mortality, as well as cost, in comparison with surgical intervention for acute colonic obstruction. Management with colonic stents can also rule out proximal synchronous lesions after initial decompression prior to definitive surgery. Benign conditions may also be treated with stents. A multidisciplinary approach for the use of colonic stents during assessment and management of acute colonic obstruction is necessary in order to achieve a satisfactory outcome, whether that be better quality of life or improved survival.