Decreased risk of stent fracture‐related restenosis between paclitaxel‐eluting stents and sirolimus eluting stents: Results of long‐term follow‐up

Objective: To compare the outcomes between paclitaxel‐eluting stents (PES) and sirolimus‐eluting stents (SES) for the treatment of drug‐eluting stent (DES) fracture. Background: DES fracture is considered as an important predictor of in‐stent restenosis (ISR). However, little data are available evaluating the optimal treatment for this complication of coronary stenting. Methods: From January 1, 2004 to December 31, 2008, patients with DES ISR treated with a second DES were identified and evaluated for stent fracture. Stent fracture was defined by the presence of strut separation in multiple angiographic projections, assessed by two independent reviewers. Target lesion revascularization (TLR) at 6 and 12 months were the primary end points. Results: Of 131 lesions with DES ISR treated with a second DES, we found 24 patients (24 lesions, 18.2%) with angiographically confirmed stent fracture. Of these, 20 patients (20 lesions) treated with either PES (n = 11/55%) or SES (n = 9/45%) were included in the study. TLR at 6 months occurred in 9% of patients treated with PES and 22% of those treated with SES (P = 0.41). After 12 months, TLR was 9% and 55.5%, respectively (P = 0.024). Conclusions: This study demonstrates a high incidence of stent fracture in patients presenting with DES ISR in need of further treatment with another DES. The suggested association between treatment of stent fracture‐associated DES ISR with PES as compared with SES, and better long‐term outcomes, is in need of confirmation by larger prospective registries and randomized trials. © 2011 Wiley Periodicals, Inc.     

Sirolimus-eluting stents for the prevention of restenosis in a worst-case scenario of diffuse and recurrent in-stent restenosis.

For recurrent in-stent restenosis (ISR), surgical revascularization or brachytherapy is still the principal therapeutic options. The present investigation explores the efficacy of a sirolimus-eluting stent to prevent restenosis in these lesions with a high risk of recurrence. In 22 consecutive patients with a recurrent and diffuse ISR, a sirolimus-eluting stent was implanted to cover the restenotic lesion. All patients were followed clinically for at least 1 year and underwent a repeat angiography after 7 months. A quantitative coronary angiographic analysis was done. The target vessel failure was 14% in the sirolimus-eluting stent group, with an angiographic late loss of only 0.39 +/- 0.54. No subacute stent thrombosis was observed, and the 1-year event-free survival was 86%. The three cases with restenosis were all focal and could be successfully treated by additional drug-eluting stent implantation. This study showed the efficacy of a sirolimus-eluting stent for the prevention of restenosis in a worst-case scenario of recurrent and diffuse ISR. The observed restenosis rate is lower than that reported after brachytherapy and suggests that sirolimus-eluting stents are a promising treatment option for ISR.     

Influence of stent surface topography on the outcomes of patients undergoing coronary stenting: a randomized double-blind controlled trial.

The objective of this study was to examine the relationship between stent surface topography and outcome in patients undergoing implantation of stents with rough and smooth surfaces. Surface topography is considered an important determinant of the bare stent performance. Specifically designed rough surface may increase the drug-storing capacity of stents but its direct impact on the risk of thrombosis and restenosis is not known. A total of 200 patients with significant stenosis in native coronary vessels were randomly assigned in a double-blind way to receive either a rough or a smooth-surface stent. The primary endpoint of the study was late lumen loss. Secondary endpoints included angiographic restenosis and clinical outcomes. The study was designed to test the equivalence of rough-surface stents to smooth-surface stents with respect to late lumen loss based on a noninferiority margin of 0.20 mm. Follow-up angiography was performed in 77% of the patients. Late lumen loss was 1.0 +/- 0.7 mm in the rough-surface stent group and 1.2 +/- 0.7 mm in the smooth stent surface group with a mean difference of -0.20 mm (95% CI = -0.43 to 0.02) between the two stents (P < 0.001 from test for equivalence and P = 0.08 from test for superiority). Angiographic restenosis rates were 25% with rough-surface stents and 35% with smooth-surface stents (P = 0.19). These results show that a rough stent surface does not increase late lumen loss after stent implantation as compared with a conventional smooth stent surface.     

Long‐term outcome of transcatheter polytetrafluoroethylene‐covered stent implantation in a giant coronary aneurysm of a child with Kawasaki disease

We report the long‐term outcome of a child with Kawasaki disease (KD), who had a giant aneurysm with stenotic lesions in the right coronary artery, resulting in the transcatheter implantation of a polytetrafluoroethylene (PTFE)‐covered stent at the age of 8. Quantitative coronary angiography analysis later showed the increase of the diameter stenosis at both stent edges for the first 10 months after implantation; however, the stenosis did not develop thereafter. Coronary perfusion was still well maintained at follow‐up coronary angiography 5.5 years after implantation (diameter stenosis was 36.5% at proximal and 37.4% at distal edge, respectively). Although further follow‐up is necessary, the long‐term outcome of a PTFE‐covered stent implantation for a KD patient is satisfactory in this instance. Implantation of a covered stent in a giant aneurysm is considered a promising treatment option. © 2012 Wiley Periodicals, Inc.     

Effect of stents in reducing restenosis in small coronary arteries: A meta‐analysis

The ability of stents to reduce restenosis was established in larger coronary arteries. Clinical trials of stenting in smaller vessels have yielded conflicting results due in part to their sample sizes. The aim of this meta‐analysis was to increase the statistical power by pooling data from these clinical trials. Trials were identified from Medline search, review of recent cardiology meetings' abstracts, and manual review of bibliographies. Studies were included if they were prospective randomized controlled trials. Endpoints examined included a dichotomized definition of angiographic restenosis, target lesion revascularization (TLR), target vessel revascularization (TVR), or any repeat revascularization. Pooling of data was performed by calculating a Mantel‐Haenszel odds ratio (OR). The analysis included 2,598 patients enrolled in eight clinical trials. Stenting significantly reduced restenosis (OR = 0.62; 95% CI = 0.61–0.63). Concordantly, stenting reduced TLR (OR = 0.49), TVR (OR = 0.90), and any revascularization (OR = 0.48). This meta‐analysis supports the hypothesis that stenting reduces restenosis in small coronary arteries as well as in larger coronary arteries. The apparent discordant result of individual clinical trials was due in part to underpowering related to small sample sizes. Catheter Cardiovasc Interv 2004;62:425–429. © 2004 Wiley‐Liss, Inc.     

Migration of covered stents from hemodialysis A‐V access to the pulmonary artery: Percutaneous stent retrieval and procedural trends

Details are presented of two patients with end‐stage renal disease (ESRD) who recently experienced migration of a Viabahn covered stent from a peripheral hemodialysis A‐V access to the right lower lobe pulmonary artery. Successful percutaneous retrieval was achieved in one patient using a dual snare approach, facilitated by ex vivo product testing. The second patient was managed conservatively. A review of the institution's A‐V access salvage procedures, indicated a concomitant trend toward greater use of stent‐assisted procedures, and a higher utilization of covered versus uncovered stents. © 2010 Wiley‐Liss, Inc.     

Membrane-covered stents: a new treatment strategy for saphenous vein graft lesions.

The restenosis rate after stenting of lesions in aortocoronary venous bypass grafts still has to be considered unsatisfactorily high. We investigated a new stent design characterized by an expandable polytetrafluorethylene (PTFE) membrane in between two layers of struts. Five consecutive male patients (age 70 +/- 6 years) were followed prospectively who presented with at least two de novo lesions in different grafts 13 +/- 3 years after bypass surgery. A total of 11 lesions were treated located in grafts anastomosed to the circumflex (n = 3), to the LAD (n = 7), and to the right coronary artery (n = 1). Within the same procedure, every patient received membrane-covered stents (n = 6) and conventional stents (n = 5) in either of their lesions. All patients underwent successful interventions. The minimal luminal diameter increased from 1.0 +/- 0.5 to 2.9 +/- 0.6 mm in lesions treated by the membrane-covered stents and from 0.8 +/- 0.4 to 2.4 +/- 0.7 mm in the lesions treated by conventional stents. During follow-up, four out of five patients required angioplasty for in-stent restenosis of lesions covered by a conventional stent, whereas no patient underwent revascularization for a lesion treated by a membrane-covered device. The mean minimal luminal diameter of lesions covered by a conventional stent decreased by 42% to 1.4 +/- 0.6 mm; the mean minimal luminal diameter of the lesions treated by a stent graft declined by 9% to 2.8 +/- 0.6 mm (P < 0.05). This series of intraindividual comparisons suggests that membrane-covered stents may have the power to reduce in-stent restenosis in obstructed aortocoronary venous bypass grafts.     

Mechanism of cutting balloon angioplasty for in-stent restenosis: an intravascular ultrasound study.

We investigated by intravascular ultrasound (IVUS) the mechanism of action of cutting balloon (CB) angioplasty in patients with in-stent restenosis. Seventy-one consecutive restenotic lesions of 66 patients were studied by quantitative coronary angiography (QCA) and IVUS before, immediately after, and, in 20 cases, at 24-hr time interval after CB. CB was selected according to 1:1 CB-to-stent ratio and inflated at 8 atm for 60-90 sec. Both IVUS planar and volumetric (Simpson's rule, 25 patients) analysis were carried out. IVUS measurements included external elastic membrane area (EEMA), stent area (SA), minimal lumen area (MLA), and restenosis area (RA). Following CB, QCA analysis showed increase of minimal lumen diameter (1.17 +/- 0.46 vs. 2.45 +/- 0.51 mm; P < 0.0001) and decrease of diameter stenosis (64% +/- 13% vs. 21% +/- 9%; P < 0.0001). IVUS measurements showed a significant increase of MLA (2.18 +/- 0.80 vs. 7.31 +/- 1.8 mm(2); P < 0.0001), SA (9.62 +/- 2.6 vs. 10.7 +/- 2.75 mm(2); P < 0.0001), and EEMA (17.27 +/- 5 vs. 18.1 +/- 5 mm(2); P < 0.0001) and a decrease of RA (7.43 +/- 2.63 vs. 3.45 +/- 1.39 mm(2); P < 0.0001). No significant change was observed in the original plaque + media area (7.65 +/- 3 vs. 7.38 +/- 2.9 mm(2); P = NS). Thus, of the total lumen enlargement (5.13 +/- 1.85 mm(2)), 23% was the result of increase in mean SA, whereas 77% was the result of a decrease in mean RA. These changes were associated with a 5% increase in EEMA. IVUS volumetric changes paralleled planar variations. Angiographic and IVUS changes were well maintained at 24 hr. CB enlarges coronary lumen mainly by in-stent tissue reduction associated with a moderate degree of additional stent expansion. Favorable QCA and IVUS acute results are maintained at 24 hr.     

In-stent restenosis in bare metal stents versus sirolimus-eluting stents after primary coronary intervention for acute myocardial infarction and subsequent transcoronary transplantation of autologous stem cells

BACKGROUND: Following stenting for acute myocardial infarction, transcoronary transplantation of granulocyte-colony stimulating factor (G-CSF) mobilized autologous stem cells (ASC) has been shown to result in an increased in-stent restenosis rate of bare metal stents (BMS). HYPOTHESIS: This study sought to compare the extent of neointimal growth in BMS and sirolimus-eluting stents (SES) after primary implantation, and subsequent transcoronary transplantation of G-CSF mobilized stem cells. METHODS: Patients with stenting of the left anterior descending coronary artery for acute anterior myocardial infarction were randomly assigned to receive a BMS or SES. Intracoronary stem cell injection was performed after G-CSF application for at least 4 d and cell apheresis. The angiograms obtained after cell transplantation and after 6 mo were analyzed by quantitative coronary angiography. RESULTS: We performed primary stenting and stem cell transplantion in 16 patients who received a BMS (n = 8) or an SES (n = 8). In 2 patients with a BMS, late stent thrombosis occurred after 58 d and 177 d, respectively. In the remaining patients, control angiography after 6 mo revealed in-stent restenosis of >50% in no patients with SES but in 4 patients with BMS (67%). Late lumen loss and in-stent plaque volume were significantly higher in patients with BMS compared with patients with SES. CONCLUSIONS: Compared with BMS, SES impair in-stent intima hyperplasia after stenting for acute myocardial infarction and transcoronary transplantation of G-CSF mobilized ASC. Copyright (c) 2008 Wiley Periodicals, Inc.     

Efficacy and safety of pimecrolimus-eluting stents in porcine coronary arteries

OBJECTIVE: We aimed to evaluate an effective dosage and safety profile of pimecrolimus as an anti-inflammatory drug for drug-eluting stents. METHODS: In the dose finding study, coronary arteries of 20 domestic swine were randomly implanted with bare metal stents (ProKinetic and Guidant Vision), the ProKinetic stent with polylactic acid (PLLA), and pimecrolimus-eluting stents (32, 75, and 120 microg) over a period of 4 weeks. In addition, pimecrolimus (75 microg) and ProKinetic stents were randomly implanted into six swine over 3 months. In the safety study, the ProKinetic stent, the ProKinetic stent with PLLA, mid- (45 microg) and high-dose pimecrolimus (120 microg), and overlapping mid-dose stents were implanted over a period of 4 weeks. Mid-dose, ProKinetic stent, and ProKinetic stent with PLLA were implanted over a period of 3 months. RESULTS: The dose finding study revealed excellent luminal patency with low percent occlusion (approximately 29% vs. approximately 41%), injury (0.53-0.59 vs. 1.25), and inflammation (0.78-0.97 vs. 1.08) for the pimecrolimus group compared with the vision group. The safety study arm showed similar angiographic results for all tested groups, with a significantly larger minimal lumen diameter for pimecrolimus stents compared to PLLA stents. Except for the high-dose group and overlapping area of the overlapping group, promising morphometric results were found for pimecrolimus compared to bare metal stents. CONCLUSIONS: Present data suggest that pimecrolimus-eluting stents are safe and have a similar healing profile to bare metal stents. They may suppress inflammation, leading to a reduced intimal response and a milder inflammatory reaction in a porcine model.     

The porcine coronary model of in-stent restenosis: current status in the era of drug-eluting stents.

Drug-eluting stents are revolutionizing interventional cardiology. Sirolimus-eluting stents are in widespread clinical use, associated with well-documented remarkably low restenosis rates, and a number of other agents appear promising in clinical trials. These human studies have been preceded by numerous animal studies, foremost among them the pig coronary model of in-stent restenosis (ISR). The histologic response to porcine coronary stenting was described over a decade ago. Porcine stenting studies now provide examinations not only of histology, but also mechanisms of action, toxicity, and biocompatibility. This review therefore examines the current status of this porcine coronary model of ISR. Contemporary methods of pig coronary stenting are discussed. The morphometric, cellular, and molecular analyses of the responses to stent injury are then described. Finally, recent pig coronary drug-eluting stent studies are examined, with a discussion of their advantages, limitations, and possible future modifications.     

冠状动脉支架术后支架内亚急性血栓形成(附5例报告)

目的评价和探讨支架内亚急性血栓（SAT）的发生机制和预防。方法随访和分析2004-2007年5例冠心病患者支架置入术后发生SAT患者的临床和冠脉造影特点。结果（1）在529例冠心病支架置入患者中有5例（0.94%）发生SAT,多于术后2～5d出现。其中3例冠脉造影证实SAT,积极治疗后6个月冠脉造影随访支架内无再狭窄;2例可能为SAT;死亡2例,1例在院外死亡,均为未及时介入治疗。（2）上述5例患者中3例表现为ST抬高型心肌梗死,1例表现为急性左心衰,心源性休克,1例表现为不稳定性心绞痛。4例患者为药物洗脱支架后SAT,1例为裸支架后SAT。结论支架内SAT可能与C型病变,术中支架贴壁不良,急性心肌梗死有关,及时介入治疗可以减少不良后果的发生。     

In‐stent neoatherosclerosis and tissue characteristics of restenotic lesions following implantation of second generation drug‐eluting stents in unrestricted coronary lesions: Optical frequency domain imaging study

BACKGROUND

Differences in stent platform, polymer coatings, and antirestenotic drugs among the current in use second‐generation drug‐eluting stents (G2‐DESs) may induce significant variations in neointimal response and vascular healing, which may impact the prevalence of neoatherosclerosis (NA) and morphological appearance of the restenotic tissue.

METHODS AND RESULTS

Utilizing Optical frequency domain imaging, two independent reviewers, retrospectively compared the prevalence of neoatherosclerosis (NA), and the morphological differences, and tissue characteristics of 50 G2‐DESs in‐stent restenosis (ISR) lesions (35 everolimus‐eluting stent [22 cobalt‐chromium (CoCr), 13 platinum‐chromium (PtCr)], and 15 biolimus‐eluting stent [BES]) implanted liberally in unrestricted coronary lesions. More than half of the stents were implanted in type C lesions, while 40% of the stents were implanted primarily in lesions with recanalized chronic total occlusion. NA, defined as a neointima formation with the presence of lipids or calcification, was observed in fewer than half (24/50) of all ISR lesions with no significant in‐between group differences (41%, 69%, and 40% in CoCr, PtCr, and BES respectively, P = 0.22), nor were there any significant differences in the morphological appearance or tissue characteristics between all G2‐DESs subtypes.

CONCLUSIONS

Acknowledging some limitations, our results may suggest that the prevalence of NA and the morphological appearance of restenotic lesions might not differ when G2‐DESs are implanted in unrestricted, rather complex, coronary lesions.

     

Balloon-based radiation therapy for treatment of in-stent restenosis in human coronary arteries: results from the BRITE I study.

Catheter-based intracoronary radiation therapy demonstrated reduction of the recurrence rate of in-stent restenosis by 35%-50% when compared to conventional therapy. The objectives of this study were to determine the safety and feasibility of a new balloon-shaped source design and a higher applied dose to reduce the restenosis rates. Thirty-two patients with in-stent restenosis who met study eligibility criteria were successfully treated with standard PCI techniques. Following a successful intervention, a P-32 beta-balloon source was positioned to cover the angioplasty site and a dose of a 20 Gy at 1 mm from the surface of the source was administered. The primary endpoint was a composite of major adverse cardiac events (any death, MI, emergent CABG, or repeat target vessel revascularization) during 6 months of follow-up. At 6 months, only one patient underwent repeat PTCA to the target vessel (3%). There were no instances of death, emergency surgery, late thrombosis, total occlusions, or MI. Binary restenosis measured by QCA at the stented segment was 0% and for the whole analysis vessel was 7.5%. Beta-radiation delivered with a balloon P-32 source design for patients with in-stent restenosis results in lower than expected rate of angiographic and clinical restenosis and the absence of late complications.     

国产无聚合物紫杉醇涂层支架和可降解聚合物雷帕霉素涂层支架治疗冠心病疗效评价

目的:探讨国产无聚合物紫杉醇涂层支架(YINYI)和可降解聚合物雷帕霉素涂层支架(EXCEL)治疗冠心病,预防心血管事件的有效性和安全性.方法:167例符合冠状动脉介入手术指征的冠状动脉病变患者被随机分为YINYI组和EXCEL组,分别接受YINYI和EXCEL治疗.12个月临床随访,观察2组支架内血栓形成事件、MAC...     

Clinical and angiographic outcomes following elective implantation of the Carbostent in patients at high risk of restenosis and target vessel failure.

The Carbostent is a new balloon-expandable, stainless steel, tubular stent with innovative multicellular design and unique turbostratic carbon coating. The aim of this study was to assess clinical and angiographic outcomes after Carbostent implantation in 112 patients poorly suitable for an effective treatment with stenting because of the high risk of thrombosis, late restenosis, and clinical target vessel failure. The inclusion criteria were age > 75 years, diabetes mellitus, a lesion length > 10 mm, a reference vessel diameter < 3.0 mm, an ostial location of the target lesion, and chronic total occlusion. Overall, a total of 175 stents ranging from 9 to 25 mm in length were placed in 147 lesions. There were no stenting attempt failures. The acute gain after stent implantation was 2.46 +/- 0.51 mm, and the residual stenosis 0 +/- 4%. No stent thrombosis occurred, nor myocardial infarction. The 6-month event-free survival rate was 74% +/- 5%. The 6-month angiographic follow-up showed a late loss of 0.81 +/- 0.88 mm and a binary (> or = 50%) restenosis rate of 25%. The results of this study suggest that the Carbostent may be highly effective in patients at high risk of restenosis and target vessel failure.     

Comparison of the effectiveness of sirolimus- and paclitaxel-eluting stents for small coronary artery lesions.

BACKGROUND: The sirolimus-eluting stent (SES) and the paclitaxel-eluting stent (PES) reduce restenosis in small coronary artery lesions. However, it is not clear which of these stents is superior in terms of clinical outcomes. METHODS: The authors retrospectively examined 197 patients with 245 de novo small coronary artery lesions (相似文献