Twelve Months Clinical Outcomes after Percutaneous Coronary Intervention with Bare Metal Stents in Unselected Real-Life Patients with Coronary Artery Disease: Results from FLEXUS Study

Background: Though drug-eluting stent is widely used during coronary angioplasty, still there are conditions in which bare metal stents possess a priority role. Objectives: The aim of FLEXUS study is to investigate the safety and efficacy of Flexinnium stent in unselected real-life patients. Methods: The FLEXUS is a single-centric, observational, non-randomized, retrospective study performed from January to August 2014 in 216 patients who received Flexinnium stent. The end-point of study included device-oriented and patient-oriented clinical outcomes as per Academic Research Consortium consensus. These end-points were observed at in-hospital stay and 12-month follow-up. Results: Of 216 patients, 174 (80.6%) patients were male;there were 76 (35.2%) and 84 (38.9%) patients of diabetes and hypertension, respectively. Type B2 and C lesions accounted for 27 (11.3%) and 122 (50.8%), respectively. A total of 241 Flexinnium stents were implanted with an average diameter and length of 2.7 ± 0.2 mm and 21.6 ± 8.0 mm, respectively. The cumulative device-oriented composite at 12-month follow-up included 2.31% cardiac death, 1.39% myocardial infarction (MI) attributed to the target vessel, and 3.70% target lesion revascularization (TLR). Conclusion: FLEXUS study gives an idea about favorable safety and efficacy of the Flexinnium in unselected real-life patients with both simple and complex coronary lesions.

Long-term effects of drug-eluting stents versus bare metal stents on patients with acute ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention： outcomes of 3-year clinical follow-up

Background The long-term safety and efficacy of drug-eluting stents （DES） versus bare metal stents （BMS） are unclear and controversial issues in patients with acute ST-elevation myocardial infarction （STEMI） undergoing primary percutaneous coronary intervention （PCI）. The purpose of this study was to compare the long-term outcome of STEMI patients undergoing primary PCI with DES versus BMS implantation. Methods A total of 191 patients with acute STEMI undergoing PCI from Jan. 2005 to Dec. 2007 were enrolled. Patients received DES （n=83） or BMS （n=108） implantation in the infarction related artery according to physician＇s discretion. The primary outcome was the occurrence of major adverse cardiac events （MACE）, which was defined as a composite of death, myocardial infarction （MI）, target vessel revascularization （TVR） and stent thrombosis. The difference of MACE was observed between DES and BMS groups. Results The clinical follow-up duration was 3 years （（41.7±16.1） months）. MACE occurred in 20 patients during three years follow-up. Logistic regression analysis showed that the left ventricular ejection fraction （LVEF） was an independent predictor for MACE in the follow-up period （P=0.0301）. There was no significant difference in all-cause mortality （3.61% vs. 7.41%, P=0.2647）, the incidence of myocardial infarction （0 vs. 0.93%, P=-0.379） and stent thrombosis （1.20% vs. 1.85%, P=0.727） between the DES group and BMS group. The incidence of MACE was significantly lower in the DES group compared to the BMS group （4.82% vs. 14.81%, P=0.0253）. The rate of TVR was also lower in the DES group （0 vs. 5.56%, P=0.029）. In the DES group, there was no significant difference in the incidence of MACE between sirolimus eluting stents （SES, n=73） and paclitaxel-eluting stents （PES, n=10） subgroups （2.74% vs. 20.00%, P 〉0.05）. Conclusions This finding suggested that drug-eluting stents significantly reduced the need for revascularization in patients with acute STEMI, without increasing the incidence of death or myocardial infarction. Use of DES significantly decreased the incidence of MACE compared with BMS during the 3-year follow-up.

Effect of self-expanding bare metal stents of different diameters on the trachea of dogs

Objective To study the effect of self-expanding bare metal stents on the trachea of dogs,and therefore to provide useful information for choice of airway stents by interventional physicians.Methods In this experiment,8beagles were randomly divided into 4 groups.Four selfexpanding metal stents of different diameters(16,18。

Comparison of drug eluting stents with bare metal stents in daily practice for bifurcation lesions in Chinese patients

Background Recently, numerous randomized and controlled trials have demonstrated great advantages of drug eluting stents （DES） with respect to significant reduction of restenosis and recurrence of symptoms and improvement of clinical outcomes after percutaneous coronary intervention （PCI）. Little is known about the comparative effects between DES and bare metal stents （BMS） for bifurcation angioplasty in the Chinese population. We compared the inpatient and 7-month follow-up outcomes between DES and BMS for the treatment of bifurcation lesions. Methods From April 2004 to October 2005, 291 Chinese patients [85.9% male, mean age （57.8± 10.4） years] underwent DES （387 lesions） and/or BMS （297 lesions） implantation for bifurcation lesions. Clinical and angiographic follow-up was performed at 7 months. Results Compared with BMS group, patients in DES group had significantly lower rates of restenosis at main branch （9.5% vs 28.7%, P 〈 0.001） or side branch （14.5% vs 37.0%, P 〈 0.001） and major adverse cardiac events （MACE） （14.0% vs 26.3%, P = 0.000）. The occurrence rate of late in-stent thrombosis did not differ between the two groups in both main （0.8% vs 0, P = 0.224） and side branches （1.4% vs 0, P =0.198）. Target lesion revascularization （TLR） was less frequent in DES group for main branch （8.3% vs 21.3%, P 〈 0.001） and for side branch （7.6% vs 23.5%, P 〈 0.001）. Multivariate regression analysis revealed that total stent length （OR = 1.029, P = 0.01）, postprocedural in-stent minimum lumen diameter （OR = 0.476, P = 0.03） and stent type （OR = 3.988, P = 0.0001） were independent predictors of TLR for main branch. Prior history of coronary intervention （OR = 2.424, P =0.041）, angulated lesion （OR = 2.337, P = 0.033）, postdilation （OR = 0.267, P = 0.035） and stent type （DES vs BMS, OR = 5.459, P = 0.000） were independent predictors of TLR for side branch. Conclusion The implantation of DES may be associated with greater reduction of restenosis and TLR than BMS in bifurcations angioplasty.

Two-year clinical outcome after successful implantation of drug-eluting and bare metal stents in diabetic patients： results from a real-world single center registry

Background Drug-eluting stents （DES） have revolutionized the field of interventional cardiology by dramatically improving clinical and angiographic outcomes. Patients with diabetes mellitus （DM） are associated with an increased risk of adverse clinical outcomes after a percutaneous coronary intervention （PCI）. Available information on the efficacy and safety of DES and bare metal stent （BMS） in diabetic patients remains scarce. Methods From April 2004 to October 2006, 1565 patients with diabetes, who successfully underwent elective stenting at Fu Wai Hospital in Beijing, China, were enrolled in this study. All enrolled patients were assigned to a drug eluting stent group and a bare metal stent group. We obtained follow-up data： death, myocardial infarction （MI）, thrombus, target lesion revascularization （TLR）, and target vessel revascularization （TVR） at 30 days and 12 and 24 months, as defined by the Academic Research Consortium （ARC）. We calculated and compared all the unadjusted cumulative frequencies of the various adverse events in the two groups. Cox＇s proportional-hazards models adjusted with the propensity score were used to assess the relative risks of all the outcome measures at 24 months. Results At 24 months, all ARC defined stent thrombosis in the two groups were similar; at 30 days, a more definite thrombosis was found in the BES group （0.08% vs 0.81%, P=0.016）. Patients treated with DES showed a significant lower risk of TLR （3.88% vs 10.89%; hazard ratio （HR） 0.159 （95% CI： 0.151-0.444）, P 〈0.001）, TVR （5.48%vs 11.69%; HR 0.383 （95% CI： 0.232-0.633）, P 〈0.001）, and any revascularization （12.47% vs 18.55%; HR 0.555 （95% CI： 0.370-0.831）, P=0.0004） at 24 months. No significant difference was apparent in terms of all-cause mortality, MI, and all-cause mortality/MI. Conclusions In contemporary society＇s large, diabetic population, the use of DES is associated with long-term significant reductions in the risks of TLR, TVR, and any revascularization. There is no significant difference in all-cause mortality, MI, and thrombosis between DES and BMS in the patients with diabetes at 24-month follow-up.

Stent fracture after transjugular intrahepatic portosystemic shunt placement using the bare metal stent/stent-graft combination technique

BACKGROUND A transjugular intrahepatic portosystemic shunt(TIPS)is widely placed to treat portal hypertension.Because the Viatorr®stent(W.L.Gore and Associates,Flagstaff,AZ,United States)is not available in all hospitals in China,the bare metal stent(BMS)/stent-graft combination technique is still popular for TIPS construction.Stent fracture is a complication after TIPS placement using this technique,with limited available literature focusing on it.AIM To assess the incidence of stent fracture after TIPS placement using the BMS/stent-graft combination technique and to identify the risk factors for stent fracture.We proposed technique modifications to improve the clinical results of TIPS placement with the BMS/stent-graft combination technique.METHODS We retrospectively analyzed the computed tomography(CT)data of all patients with portal hypertension who underwent the TIPS procedure between June 2011 and December 2021 in a single center.Patients implanted with the BMS/stent graft and had follow-up imaging data available were included.We identified patients with stent fracture and analyzed their characteristics.Multivariable logistic regression was applied to identify the potential predictors of stent fracture.RESULTS Of the 68 included patients,stent fracture occurred in seven(10.3%)patients.Based on CT images,the stent fractures were categorized into three types.Our study consisted of four(57.1%)type I fractures,one(14.3%)type II fracture,one(14.3%)type IIIa fracture,and one(14.3%)type IIIb fracture.After adjusting for covariates,multivariable logistic regression revealed that the risk factors for stent fracture were the implantation of a greater number of stents[adjusted odds ratio(aOR)=22.2,95%confidence interval(CI):1.2-415.4,P=0.038]and a larger proximal sagittal stent bending angle(aOR=1.1,95%CI:1.0-1.3,P=0.020).CONCLUSION Stent fracture occurred in approximately 10%of patients with portal hypertension who underwent TIPS with the BMS/stent-graft combination technique.The number of implanted stents and stent bending angle at the inferior vena cava end were predictors of stent fracture,which suggests that the incidence of stent fracture could potentially be reduced by procedural modifications.

Comparison of drug-eluting stents with bare metal stents implantation for the treatment of acute ST-elevation myocardial infarction： 2-year clinical outcomes from single-center registry

Background Some larger scale, randomized studies have demonstrated the superiority of drug-eluting stents （DES） over bare metal stents （BMS） for the treatment of acute myocardial infarction （AMI）. This study aimed to investigate the impact of DES, in comparison with BMS, on the 2-year clinical outcomes in patients with ST-elevation myocardial infarction （STEMI）.Methods From January 2002 to December 2008, a total of 1301 consecutive STEMI patients treated with coronary stenting in Shenyang Northern Hospital were prospectively registered. Patients received BMS （n=868） or DES （n=435） implantation in the infarction related artery according to physician＇s discretion. A propensity score analysis was performed and two well matched subgroups were selected （BMS, n=288; DES, n=288） to evaluate the 2-year clinical outcomes. The primary outcome was the occurrence of major adverse cardiac events （MACE）, which was defined as a composite of all-cause death, myocardial infarction （MI）, or target vessel revascularization （TVR）.Results Survival salvage analysis showed that 2-year cumulative hazards were not significantly different between the two groups with respect to TVR （2.8% vs. 3.1%, log-rank P=0.780）, stent thrombosis （1.7% vs. 4.2%, log-rank P=0.079） and MACE （8% vs. 10.8%, log-rank P=0.236）. Multivariate analysis showed that DES was an independent protective factor of MI （HR： 0.211, 95% CI： 0.049 to 0.908） and stent thrombosis （HR： 0.327, 95% CI： 0.107 to 0.994）.Conclusion DES was associated with similar 2-year clinical outcomes to those of BMS for the treatment of STEMI in daily practice.

A Novel High Nitrogen Nickel-free Coronary Stents System: Evaluation in a Porcine Model

Objective To study the safety of the novel high nitrogen nickel-free austenitic stainless steel bare metal stents （BMS） in a recognized porcine coronary model and to select a better grid structure of it. Methods Three types of stents were randomly implanted in different coronary arteries of the same pig： 316L stainless steel BMS （316L-BMS） （n=12）, novel high nitrogen nickel-free stents Grid A （NF-A-BMS） （n=12） and novel high nitrogen nickel-free stents Grid B （NF-B-BMS） （n=12）. In total, eighteen animals underwent successful random placement of 36 oversized stents in the coronary arteries. Coronary angiography was performed after 36 d of stents implantation. Nine animals were respectively sacrificed after 14 d and 36 d for histomorphologic analysis. 〈br〉 Results Quantitative coronary angiography （QCA） showed similar luminal loss （LL） in the three groups：（0.21±0.17） mm for 316L-BMS, （0.16±0.12） mm for NF-A-BMS, （0.24±0.15） mm for NF-B-BMS （P=0.05）. Histomorphomeric analysis after 15 d and 36 d revealed that there was also no significant difference among the three groups in neointimal area （NA） with similar injury scores respectively. High magnification histomorphologic examination showed similar inflammation scores in the three groups, but NF-A-BMS group had poorer endothelialization scores compared with NF-B-BMS group, 2.00±0.63 vs. 2.83±0.41 （P=0.015） at 15 d, which also could be proved by the scanning electron microscope. However, the difference could not been observed at 36 d. Conclusion The novel NF-BMS showed similar safety as 316L-BMS during the short-term study. NF-B-BMS had better endothelialization than NF-A-BMS and this may owe to the specific strut units.

Clinical outcomes and cost-utility after sirolimus-eluting versus bare metal stent implantation

Background Randomized studies have shown beneficial effects of drug-eluting stent （DES） in reducing the risk of repeated revascularization. Other studies have shown higher proportion of death, myocardial infarction （MI） and increased cost concerning DES. However the long term safety and effectiveness of DES have been questioned recently.Methods To compare long term clinical outcomes, health-related quality of life （HRQOL） and cost-utility after sirolimus-eluting stent （SES） and bare metal stent （BMS） implantation in angina patients in China, 1241 patients undergoing percutaneous coronary revascularization （PCl） with either SES （n=632） or BMS （n=609） were enrolled continuously in this prospective, nonrandomized, multi-center registry study.Results Totally 1570 stents were implanted for 1334 lesions. Follow-up was completed in 1205 （97.1%） patients at 12 months. Rates of MI, all causes of death were similar between the two groups. Significant differences were found at rate of cardiovascular re-hospitalization （136 （22.4%） in BMS group vs. 68 （10.8%） in SES group, P=0.001） and recurrent angina （149 （24.5%） vs. 71 （11.3%）, P=0.001）. Dramatic difference was observed when compared the baseline and 9-month HRQOL scores intra-group （P 〈0.001）. However no significant difference was found inter-group either in baseline or follow-up HRQOL. Compared with SES, the total cost in BMS was significantly lower on discharge （62 546.0 vs. 78 245.0 Yuan, P=0.001）. And follow-up expenditure was remarkably higher in the BMS group than that in the SES group （13 412.0 vs. 8 812.0 Yuan, P=0.0001）.Conclusions There were no significant differences on death, in-stent thrombosis, MI irrespective of stent type. SES was superior to BMS on improvement of life quality. SES was with higher cost-utility compared to BMS.

The role of porosity and 3D cross-stent configuration of multiple overlapping uncovered stents in the management of complex aortic aneurysms-Insights from haemodynamics

Background:Multiple overlapping uncovered stents(MOUS)have been introduced to manage complex aortic aneurysms with vital branches involvement.It has been shown that the porosity is a key determinant of the treatment outcome.However,the role of 3D cross-stent configuration remains unclear.Methods:One patient with a complex aortic aneurysm judged not suitable for open surgery nor endovascular repair was invited to participate this study.In total,four bare metal stents were deployed.3D lesion geometry was reconstructed based on pre-and post-operative CTA,and the zero-pressure configuration was recovered using an inverse procedure.Local haemodynamic parameters,including wall shear stress(WSS),oscillatory shear index(OSI),and particle relative resident time(RRT),as well as the vessel structural stress(VSS),were quantified using one-way fluid-structure interaction(FSI)analysis.In comparison to MOUS,a corresponding compact model was reconstructed by projecting inner layer stents to the most outer layer to form a single layer to eliminate the 3D cross-stent configuration and one-way FSI analysis was performed.Results:Results obtained showed that the porosity decreased linearly with the number of stents.When the 1st stent was deployed,the mean velocity decreased 36.4%and further reduction of 49.3%,59.8%,and 62.8%were observed when the 2nd,3rd and 4th stents were deployed.WSS also decreased with the number of stents deployed,and both OSI and RRT increased,but the increase was very minor with the 4th stent.MOUS deployment induced high VSS concentration in the landing zone while the VSS and pressure in the sac remained nearly unchanged.The compact model yielded a small difference in the value of flow-related parameters and 10%–20%reduction in VSS.Conclusion:Compared with porosity,the 3D cross-stent of MOUS configuration plays a minor role in the modulation of local haemodynamics.A compact model does not reduce high VSS concentration in the diseased region significantly.

Multi-link Vision and MiniVision stent registry in Asian patients with coronary artery disease:a prospective,multi-center study

Background Recent studies have showed that the fine mesh stents are associated with a significant reduction in both clinical and angiographic re-stenosis of the coronary arteries. To maintain a very satisfactory radio-opacity using the stents, Guidant of the USA has designed a new type of bare metal stents （BMS）-Multi-link （ML） Vision / ML MiniVision stents. The clinical outcomes of Asian patients with coronary artery disease （CAD） after implanting the Multi-link Vision or MiniVision stent were investigated in this study. Methods An observational, prospective, multi-center, non-randomized post marketing registry was conducted to demonstrate the efficacy of the BMS- ML Vision / ML MiniVision stents. The primary end point of the registry was clinical target lesion revascularization （TLR） at a 6-month follow-up. The major secondary end points included the rate of major adverse cardiac events （MACE） and serious adverse events （SAE） in hospital and at 6 months; and the rate of clinical TLR as a function of the type of angina. A total of 429 Asian people with 449 lesions from 14 centers were selected for this study, The average reference diameter of the lesions was （3.0±0.5） mm, and the mean length was （15.7±5.0） mm. Results The successful rate of the procedure was 99.3%. Twenty-five percent of the lesions were treated by direct stenting without pre-dilation. Eighty-six percent of the lesions were implanted with ML Vision stent. After the 6-month follow-up, the rate of clinical TLR was 1.4%. The MACE, SAE and target vessel revascularization （TVR） were 6.8%, 3.5% and 1.4% respectively. Conclusion The current registry showed the excellent 6-month clinical outcomes of ML Vision/ML MiniVision stents in Asian patients with CAD.

Meta-analysis of stent thrombosis after drug-eluting stent implantation： 4-year follow-up

Background Drug-eluting stents （DES） are the most common device used in percutaneous treatment of coronary artery disease. Recently, there has been an increased concern regarding their safety profile, in particular the late and very late stent thrombosis rate compared to bare metal stents （BMS）. The aim of the study was to compare the reported incidence of late and very late stent thrombosis of DES and BMS in patients from published clinical studies with an extended follow-up period to four years.Methods A search strategy was developed to identify publications reporting on late or very late thrombosis of BMS and DES available through MEDLINE and Cochrane Library databases. Two independent reviewers appraised eligible studies and extracted data. Odds ratios （OR） were calculated for each outcome and presented with 95% confidence intervals （CI）.Results Fourteen randomized controlled trials, which were at least single blinded, were identified. There was no difference in the incidence of late and very late stent thrombosis in patients treated with DES compared with patients treated with BMS （late OR 0.55, 95%Cl 0.23-1.31 and late/very late OR=1.08, 95%CI 0.61-1.91）.Conclusions The safety profile of DES was similar to BMS in terms of stent thrombosis. We found no evidence of increased risk of late and very late thrombosis for DES.