Bare-metal Stent In-stent Restenosis Research Articles

Management of In-stent Restenosis

Despite recent improvements in percutaneous coronary intervention (PCI), in-stent restenosis (ISR) — which accounts for 5–10% of all PCI procedures in contemporary clinical practice remains a substantial problem and the most frequent reason for stent failure. While the absolute number of ISR-PCI operations performed in contemporary practice has increased as a result of rising procedural volume and complexity, the relative rate of ISR has decreased with newer-generation drug eluting stents (DESs) in comparison to the bare metal stent (BMS) period. While BMS ISR is usually early and characterized by neointimal hyperplasia, DES ISR tends to be late with neoatherosclerosis as a characteristic feature. According to recent research, drug-coated balloons or DESs are the most effective therapy options for the majority of ISR cases. Future ISR interventional paradigms may be influenced by intravascular imaging (IVI) ISR tissue patterns. IVI can provide useful information to guide treatment options in ISR-PCI.

The relationship between serum vitamin d and bare-metal in-stent restenosis in patients with stable coronary artery disease

Aim: It has been shown that low levels of vitamin D are associated with increased cardiovascular risk factors and adverse events. The relationship between serum vitamin D level and bare-metal stent in-stent restenosis was investigated in our study.Material and Methods: A total of 181 patients with stable coronary artery disease and previously implanted (>3 months) bare-metal stent were included in the study. Two groups were formed according to angiographic results as Group 1 (≥50% in-stent stenosis) and Group 2 (<50% in-stent stenosis). Serum vitamin D measurements were performed by reverse-phase HPLC. Results: The mean serum vitamin D levels were found to be significantly lower in Group 1 compared to Group 2 (17.7 ± 5.3 ng/ml and 20.9 ± 6.7 ng/ml, p<0.01, respectively) and length of stent was longer in Group 1 compared to Group 2 (18.7 ± 5.3 mm and 17.1 ± 11.2 mm, p<0.01, respectively). In multivariate logistic regression analysis, only low level of serum vitamin D and stent length were independent risk factors for bare-metal in-stent stenosis.Conclusion: Low level of vitamin D might be related to fibrosis and inflammation resulting in in-stent stenosis. Further studies are warranted to determine whether vitamin D supplementation could prevent progression of stent re-stenosis.

Trends and Outcomes of Restenosis After Coronary Stent Implantation in the United States

BackgroundThere is a paucity of data on the burden of in-stent restenosis (ISR) in the United States as well as on its presentation and appropriate treatment strategies. ObjectivesThis study aims to provide an analysis of the temporal trends, clinical presentation, treatment strategies, and in-hospital outcomes of patients undergoing percutaneous coronary intervention (PCI) for ISR in the United States. MethodsThis study is a retrospective analysis of data collected in the Diagnostic Catheterization and Percutaneous Coronary Intervention (CathPCI) registry of the National Cardiovascular Data Registry (NCDR) between 2009 and 2017. Of the total patients undergoing PCI, we identified those undergoing PCI for ISR lesions. For comparison of in-hospital outcomes, propensity-score matching was employed. ResultsAmong the 5,100,394 patients undergoing PCI, 10.6% of patients underwent PCI for ISR lesions. Patients with bare-metal stent ISR declined from 2.6% in 2009 Q3 to 0.9% in 2017 Q2 (p < 0.001), and drug-eluting stent ISR rose from 5.4% in 2009 Q3 to 6.3% in 2017 Q2 (p < 0.001). Patients with ISR PCI were less likely to present with non–ST-segment elevation myocardial infarction (MI) (18.7% vs. 22.5%; p < 0.001) or ST-segment elevation MI (8.5% vs. 15.7%; p < 0.001). In the propensity-matched population of patients, there were no significant differences between patients with ISR and non-ISR PCI for in-hospital complications and hospital length of stay. ConclusionsISR represents approximately 10% of all PCI and is treated most commonly with another stent. Approximately 25% of patients present with acute MI. In-hospital outcomes of patients with ISR PCI are comparable with those undergoing non-ISR PCI.

Leave nothing behind: Promising results for coronary drug‐coated balloons in clinical practice

1,025 patients with de novo coronary artery disease (66.9%) or in-stent restenosis (ISR) (33.1%) underwent treatment with paclitaxel drug-coated balloons in a multinational single-arm registry. Bail-out stenting rate was only 4.8%. One-year target lesion revascularization was 2.3% for de novo lesions, 2.9% for bare metal stent ISR, and 5.8% for drug-eluting stent ISR. Short-term results with coronary drug-coated balloons are promising. Nonetheless, long-term data, preferably from randomized trials are necessary to confirm their safety and efficacy.

Angiographic and clinical performance of a paclitaxel-coated balloon compared to a second-generation sirolimus-eluting stent in patients with in-stent restenosis: the BIOLUX randomised controlled trial.

Although several studies have shown positive outcomes after the use of drug-coated balloons (DCB) for in-stent restenosis (ISR), data on randomised controlled trials versus latest-generation drug-eluting stents (DES) are limited. Therefore, in this randomised trial, we sought to evaluate whether a butyryl-tri-hexyl citrate (BTHC)-based paclitaxel DCB is non-inferior to a biodegradable polymer sirolimus-eluting stent (BP-SES) therapy in patients with ISR in either a bare metal stent (BMS) or DES. A total of 229 patients with ISR in BMS or DES from 13 German centres and one Latvian centre were 2:1 randomly allocated to DCB (n=157) or DES (n=72). The primary efficacy endpoint was defined as in-stent late lumen loss (LLL) at six months, and the primary safety endpoint was target lesion failure (TLF) at 12 months. LLL in the DCB arm was 0.03±0.40 mm compared to 0.20±0.70 mm in the DES arm (p=0.40). DCB proved to be non-inferior to DES (Δ = -0.17±0.52 mm, 97.5% CI -∞; -0.01]; p<0.0001). At 12 months, Kaplan-Meier TLF estimates were 16.7% in the DCB arm and 14.2% in the DES arm (p=0.65) and remained similar at 18 months (DCB versus DES: 17.4% versus 19.5%, p=0.88). In patients with DES or BMS ISR, treatment with a paclitaxel DCB showed similar LLL at six months and TLF rates up to 18 months compared to a second-generation sirolimus DES.

Risk Factors Associated with Acute Coronary Syndrome after Successful Percutaneous Coronary Intervention

Abstract Objective: Admission for acute coronary syndrome after successful percutaneous coronary intervention is a delicate situation for the patient and doctor. Predictors of these cases are poorly described. Methods: We retrospectively analysed the files of post-percutaneous coronary intervention patients admitted to the Department of Cardiology of the Institute for Cardiovascular Disease and Heart Transplant in Tirgu Mures between January 2012 and December 2015. Analyses using the t-test, chi-square test, and Fisher test were performed to compare demographics, clinical and angiographic characteristics of patients with acute coronary syndrome, patients with stable angina, and those without symptoms. Results: One hundred eighty post-percutaneous coronary intervention patients were readmitted; 46 patients (25.55%) were readmitted for acute coronary syndrome. Histories of arterial hypertension and renal dysfunction at hospital admission were associated with acute coronary syndrome. Bare metal stent in-stent restenosis and localisation of bare metal stent in-stent restenosis of the left descendent coronary artery were angiographic predictors of acute coronary syndrome. Conclusion: Several clinical and angiographic factors identify patients at high risk for acute coronary syndrome after successful percutaneous coronary intervention. Recognition and treatment of these factors may prevent readmission for such a dangerous condition and may improve outcomes.

Early in-stent restenosis after revascularization in patients with ST-elevation myocardial infarction

Background and aim: Obstructive coronary disease is one of the most important causes of death worldwide. Percutaneous coronary intervention is one of the most important treatments of this pathology. Using of coronary artery stents represented a major advance in interventional cardiology. While bare metal stents (BMS) set the reference point for improved safety over balloon-angioplasty, first-generation drug-eluting stents demonstrated significant improvements in efficacy, but not necessarily safety, and further technologic developments have focused on optimizing both. Methods: We studied 228 patients with STEMI in the last 6 months, divided in 2 groups – in the first group are 122 patients (53.5%) who developed in stent restenosis and the second group has 106 patients had no signs of restenosis (46.5%). The mean time of performing the angiographic reevaluation was 111 days for the first group and 154 days for the second group. The clinical signs that indicate the need of coronary reevaluation was stable angina (116, 50.87%), acute coronary syndrome (58, 25.4%) and asymptomatic patients (64, 28.9%). The cardiovascular risk factors correlate with high risk of restenosis was diabetes (24.3% in first group and 12.2% in the second one, p=0.004), active smoking (p=0.010) and metabolic syndrome (p=0.003). The stent’s length &gt;28mm, stent’s diameter ≤ 2.5 mm and chronic occlusion correlate with high risk of in-stent restenosis in BMS. Conclusion: Understanding the importance of risk factors control, will reduce the risk of restenosis, of other cardiovascular event, even sudden death.

Coronary stents and vascular response to implantation: literature review.

Drug-eluting stents (DESs) have minimized the limitations of bare-metal stents (BMSs) after percutaneous coronary interventions. Nevertheless, serious concerns remain about possible late complications of stenting, such as stent thrombosis (ST) and in-stent restenosis (ISR), although the introduction of second-generation DESs seems to have softened the phenomenon, compared to the first-generation ones. ST is a potentially catastrophic event, which has been markedly reduced by optimization of stent implantation, novel stent designs, and dual antiplatelet therapy. The exact mechanism to explain its occurrence is under investigation, and, realistically, multiple factors are responsible. ISR of BMSs has been previously considered as a stable condition with an early peak (at 6 months) of intimal hyperplasia, followed by a regression period beyond 1 year. On the contrary, both clinical and histologic studies of DESs have demonstrated evidence of continuous neointimal growth during long-term follow-up, named “late catch-up” phenomenon. The acknowledgment that ISR is a relatively benign clinical condition has been recently challenged by evidences which reported that patients with ISR can experience acute coronary syndromes. Intracoronary imaging is an invasive technology that allows identifying features of atherosclerotic plaque of stent implanted and of vascular healing after stenting; it is often used to complete diagnostic coronary angiography and to drive interventional procedures. Intracoronary optical coherence tomography is currently considered a state-of-the-art imaging technique; it provides, compared to intravascular ultrasound, better resolution (at least >10 times), allowing the detailed characterization of the superficial structure of the vessel wall. Imaging studies “in vivo,” in agreement with histological findings, suggest that chronic inflammation and/or endothelial dysfunction may induce late de novo “neoatherosclerosis” inside both BMSs and DESs. So, neoatherosclerosis has become the prime suspect in the pathogenesis of late stent failure.

Intravascular ultrasound assessment of minimum lumen area and intimal hyperplasia in in-stent restenosis after drug-eluting or bare-metal stent implantation. The Nordic Intravascular Ultrasound Study (NIVUS).

Drug-eluting stents (DES) reduce the risk of restenosis after percutaneous coronary intervention. The aim of the study was to evaluate, by intravascular ultrasound (IVUS), the minimum lumen area site in the stented segment and the distribution of intimal hyperplasia in patients presenting with a DES or bare-metal stent (BMS) in-stent restenosis. The "Nordic Intravascular Ultrasound Study (NIVUS)" study was conducted in Nordic and Baltic countries as a prospective multicenter registry. Two hundred nine patients (DES n=121 and BMS n=88) with in-stent restenosis were enrolled. At the minimum lumen area site in the stented segment, the stent area (5.8±2.2mm2 vs. 7.6±2.4mm2, p<0.001) and intimal hyperplasia area (2.6±2.0mm2 vs. 5.0±2.2mm2, p<0.001) were significantly lower in patients treated with DES compared to BMS. The percentage of stents that did not have a minimum stent area of at least 5.0mm2 (under expansion) was higher in DES (58.7% vs. 37.7%, p=0.008) compared to BMS. Intimal hyperplasia covered 55.4±33.3% of the stent length in the DES compared to 90.7±17.4% in the BMS group, p<0.001. Focal in-stent restenosis was more often seen in DES treated patients compared to BMS treated patients (DES n=84 (59.9%) vs. BMS n=15 (17.0%), p<0.001). Stent underexpansion was more often seen in DES than BMS in-stent restenosis. DES more often had focal in-stent restenosis with less intimal hyperplasia.

Abstract 340: Drug-Eluting Balloon Versus Everolimus-Eluting Stent for Restenosis in a Bare-Metal Stent: A Meta-Analysis of Randomized Trials

Background: In-stent restenosis accounts for major morbidity and mortality among patients treated with Bare-Metal Stents (BMS). Early efforts to treat BMS in-stent restenosis with plain balloon angioplasty and first generation drug eluting stents (DES) have been ineffective, leaving drug-eluting balloon (DEB) and second generation DES, such as everolimus eluting stents (EES), as the only remaining options. For BMS in-stent restenosis, studies performed so far have yielded conflicting results, while prior meta-analyses have been influenced by inclusion of observational studies. This is the first meta-analysis to compare EES versus DEB using results from only randomized controlled trials (RCTs). Methods: A systematic search of PUBMED and EMBASE databases was conducted from first available date to August, 2016 for RCTs comparing DEB with EES. Two reviewers evaluated studies for eligibility and extracted data with binary restenosis rate as the main endpoint. We identified 901 unique citations. Odds ratios were pooled using random-effects modeling. Funnel plots were used to assess publication bias. Heterogeneity was assessed using I 2 statistic. All analysis were performed using Review Manager (RevMan) version 5.3 (Cochrane Collaboration, 2014). Results: Three RCTs met study eligibility criteria, with 684 patients and a mean follow-up of 9.5 months. There were 184 and 185 patients in the EES and DEB arms respectively. In pooled analyses, EES was not superior to DEB in binary restenosis rates (pooled odds ratio: 0.76; 95% confidence interval: 0.25-2.32; P=0.14). Heterogeneity was minimal (I 2 = 49%), and the funnel plot did not suggest publication bias. Conclusion: In patients with BMS in-stent restenosis, there were no significant differences in binary restenosis rates between EES and DEB. Our results can enhance physician decision-making regarding choice of revascularization tool in this patient population.

The Relationship Between Lymphocyte-to-Monocyte Ratio and Bare-Metal Stent In-Stent Restenosis in Patients With Stable Coronary Artery Disease.

In-stent restenosis (ISR) is a common clinical problem in patients with coronary artery disease treated with percutaneous coronary intervention. Inflammatory process plays a pivotal role in the development of ISR. Both lymphocytes and monocytes are associated with inflammatory status. Recently, it has been shown that the lymphocyte-to-monocyte ratio (LMR) is a novel inflammatory marker. We aimed to investigate the association of serum LMR levels and ISR in patients undergoing bare-metal stent (BMS) implantation. The study included 273 patients (aged 61 ± 11 years, 66.5% men) with a history of BMS implantation and a further control coronary angiography due to stable angina pectoris. Patients were divided into 2 groups: patients with and without ISR. The LMR levels were significantly lower in patients with ISR than in those without ISR (2.50 ± 0.95 vs 3.87 ± 1.51, respectively, P < .001). On multivariate logistic regression analysis, the LMR was independently associated with ISR (odds ratio [OR]: 0.310, 95% confidence interval: 0.166-0.579, P < .001) together with high-sensitivity C-reactive protein (OR: 1.244, P = .008), reason for stent implantation (OR: 6.566, P = .003), stent diameter (OR: 0.015, P < .001), and stent length (OR: 1.137, P = .007). In conclusion, LMR levels are inversely related to ISR in patients treated with BMS implantation.

Everolimus-Eluting Stents in Patients With Bare-Metal and Drug-Eluting In-Stent Restenosis: Results From a Patient-Level Pooled Analysis of the RIBS IV and V Trials.

Treatment of patients with drug-eluting stent (DES) in-stent restenosis (ISR) is more challenging than that of patients with bare-metal stent ISR. However, the results of everolimus-eluting stents (EES) in these distinct scenarios remain unsettled. A pooled analysis of the RIBS IV (Restenosis Intra-Stent of Drug-Eluting Stents: Paclitaxel-Eluting Balloon vs Everolimus-Eluting Stent) and RIBS V (Restenosis Intra-Stent of Bare Metal Stents: Paclitaxel-Eluting Balloon vs Everolimus-Eluting Stent) randomized trials was performed using patient-level data to compare the efficacy of EES in bare-metal stent ISR and DES-ISR. Inclusion and exclusion criteria were identical in both trials. Results of 94 patients treated with EES for bare-metal stent ISR were compared with those of 155 patients treated with EES for DES-ISR. Baseline characteristics were more adverse in patients with DES-ISR, although they presented later and more frequently with a focal pattern. After intervention, minimal lumen diameter (2.22±0.5 versus 2.38±0.5 mm, P=0.01) was smaller in the DES-ISR group. Late angiographic findings (89.3% of eligible patients), including minimal lumen diameter (2.03±0.7 versus 2.36±0.6 mm, P<0.001) and diameter stenosis (23±22 versus 13±17%, P<0.001) were poorer in patients with DES-ISR. Results were consistent in the in-segment and in-lesion analyses. On multiple linear regression analysis, minimal lumen diameter at follow-up remained significantly smaller in patients with DES-ISR. Finally, at 1-year clinical follow-up (100% of patients), mortality (2.6 versus 0%, P<0.01) and need for target vessel revascularization (8 versus 2%, P=0.03) were higher in the DES-ISR group. This patient-level pooled analysis of the RIBS IV and RIBS V randomized clinical trials suggests that EES provide favorable outcomes in patients with ISR. However, the results of EES are less satisfactory in patients with DES-ISR than in those with bare-metal stent ISR. URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01239953 and NCT01239940.

Long-Term Clinical Outcomes After Bioresorbable Vascular Scaffold Implantation for the Treatment of Coronary In-Stent Restenosis: A Multicenter Italian Experience.

Treatment of in-stent restenosis (ISR) is still challenging. In this setting, the use of bioresorbable vascular scaffold (BVS) seems attractive because it allows drug delivery combined with transient vessel scaffolding. We aimed to investigate the long-term results after BVS use in ISR lesions. A prospective analysis was performed on all patients who underwent percutaneous coronary intervention with BVS implantation for ISR at 7 Italian Centers. Primary end point was the device-oriented composite end point (cardiac death, target vessel myocardial infarction, and ischemia-driven target lesion revascularization) at the longest follow-up available. From April 2012 to June 2014, 116 patients (127 lesions) underwent percutaneous coronary intervention for ISR with BVS implantation. Among the ISR lesions, the majority were drug-eluting stent ISR (78, 61.6%), de novo ISR (92, 72.4%), and diffuse ISR (81, 63.8%). Procedural success was achieved for all (100%) patients. No in-hospital death, myocardial infarction, or revascularization occurred. At 15 months of follow-up, the incidence of the device-oriented composite end point estimated with the Kaplan-Meier method was 9.1%. No significant differences were reported between drug-eluting stent and bare-metal stent ISR groups in terms of device-oriented composite end point (10.9% versus 6.4%; hazard ratio, 1.7; 95% confidence interval, 0.5-6.5; P=0.425) and its singular components (cardiac death: 2.8% versus 2.0%, hazard ratio, 1.3; 95% confidence interval, 0.1-14.1, P=0.843; target vessel myocardial infarction: 1.5% versus 0%, P=0.421; ischemia-driven target lesion revascularization: 9.6% versus 4.4%, hazard ratio, 2.3; 95% confidence interval, 0.5-10.8, P=0.309). Our registry suggests that the use of BVS implantation for the treatment of complex drug-eluting stent and bare-metal stent ISR lesions might be associated with acceptable long-term clinical outcomes.

A comparison of drug-eluting stent versus balloon angioplasty in patients with bare-metal stent instent restenosis: 5 year outcomes

ObjectivesThe objective of the present study was to compare the long term outcomes of balloon angioplasty (BA) versus drug-eluting stents (DES) in bare-metal stent in-stent restenosis (BMS-ISR). BackgroundCoronary in-stent restenosis (ISR) remains a significant clinical problem. Long term results after management of ISR may help improve treatment strategies. MethodsWe assessed 5-year clinical outcomes in cohort of 269 patients with BMS-ISR treated with DES (n=154) and BA (n=115) between June 2007 and January 2010 at our institution. ResultsClinical and demographic characteristics were similar for both groups. Mehran classification was used to classify ISR lesions. BA were used predominantly in classes I and II, whereas classes III and IV were treated with DES (p<0.0001). Percentages of major adverse cardiovascular events (MACE) including death, myocardial infarction (MI) and target vessel revascularization (TVR) for 4.37±1.1years were 50.4% and 31.8% for the BA and DES groups, respectively (p=0.002). Although patients in the BA group had significantly higher rates of recurrent angina (42.6% vs. 27.3%, p=0.009) and TVR (37.4% vs. 20.8%, p=0.003), MI (6.1% vs. 5.2%, p=0.752) and cardiac death (21.7% vs. 16.2%, p=0.251) were similar in both groups. MACE-free 1-year survival and 5-year survival rates were significantly higher in DES group compared to BA group (1year survival: 91.6% vs. 71.3 p<0.001, and 5year survival: 68.2% vs. 49.6%, p<0.0001, respectively). ConclusionsAlthough DES were more frequently used in to treat complicated lesions in patients with ISR, follow-up MACE rates were significantly lower and MACE-free survival was significantly better in the DES treated patients.

The Leipzig Prospective Drug-Eluting Balloon-Registry – Outcome of 484 Consecutive Patients Treated for Coronary In-Stent Restenosis and De Novo Lesions Using Paclitaxel-Coated Balloons –

Drug-eluting balloons (DEB) are an alternative treatment of in-stent restenosis (ISR), but data regarding outcomes of DEB in de novo lesions are lacking. We investigated the effect of DEB on target lesion revascularization (TLR), procedural complications (coronary dissection/rupture, pericardial effusion, stent thrombosis, peri-interventional NSTEMI, stroke), major adverse cardiac and cerebrovascular events (all-cause mortality, myocardial infarction, TLR, stroke) in patients with ISR and de novo lesions in an all-comers setting. Between April 2009 and October 2013, 484 consecutive patients (mean age 68.4 years; 77.9% male) were enrolled in a prospective registry. TLR rate was 4.9% at 12 months and 8.7% at long-term follow-up of 2.3 years. Subgroup analysis confirmed a TLR rate of 8.9% after DEB treatment of ISR in bare-metal stents (21/235 lesions), 13.0% in drug-eluting stents (21/161 lesions) and 0% for de novo lesions (0/76 lesions). At long-term follow-up, all-cause mortality/cardiac mortality was 8.7% (42/484)/3.3% (16/484) and MACCE rate was 18.4% (89/484 patients), with no differences between DEB for ISR compared with de novo lesions. DEB for ISR resulted in a low rate of TLR. Our data support DEB in ISR as an effective treatment option. DEB in small coronary vessels in our limited cohort appeared to be safe. Larger, randomized trials in small coronary vessels should be undertaken to verify the long-term results of the current trial.

Associations Between Target Lesion Restenosis and Drug-Eluting Balloon Use: An Observational Study.

Percutaneous coronary interventions (PCIs) with drug-eluting balloons (DEBs) have emerged as an adjunctive treatment for in-stent restenosis (ISR) lesions. However, recurrent restenosis still occurs following DEB use. Our study aimed to identify the associations of target lesion restenosis following DEB use over a 1-year clinical follow-up.Between November 2011 and May 2014, 246 patients were diagnosed with coronary artery ISR in our hospital. A total of 335 coronary ISR lesions were treated with DEBs. The 1-year patent coronary artery group was defined as those with negative noninvasive examinations and no clinical symptoms, or those with no angiographic restenosis. The 1-year current restenosis group was defined as those with angiographic restenosis. Clinical results were compared between 2 groups. Univariate and multivariate cox regression analyses were performed to identify the associations of target lesion restenosis following DEB use.Patients’ average age was 64.96 ± 10.68 years, and 77.2% were men. Non-ST segment elevation myocardial infarction was more frequent as the clinical presentation in the 1-year current restenosis group, whereas stable angina was more frequent in the 1-year patent coronary artery group. The 1-year current restenosis group exhibited higher percentages of comorbidities, including hypertension, diabetes, prior myocardial infarction, heart failure, prior coronary artery bypass grafting, and end-stage renal disease (ESRD). Regardless of ostial ISR or nonostial ISR, the results of drug-eluting stent ISR were worse than those for bare-metal stent ISR. Multivariate analysis revealed that ESRD, and coronary ostial lesion, and the severity of pre-PCI stenosis were independently associated with target lesion restenosis following DEB use (P = 0.020, P = 0.009, P = 0.026, respectively).ESRD, and coronary ostial lesion, and the severity of pre-PCI stenosis were independently associated with recurrent target lesion restenosis following DEB use.

Optimal interventional strategy for the treatment of coronary in-stent restenosis.

In-stent restenosis (ISR) has been an important issue in the era of percutaneous coronary intervention (PCI) since the first bare metal stent (BMS) was applied to clinical settings. BMS substantially reduces acute vessel closure and restenosis after PCI by attenuating early arterial recoil and contraction, two major limitations of plain old balloon angioplasty (POBA). Thereby, it has been considered as a major advancement over POBA. However, ISR caused by neointimal hyperplasia after stent implantation hampers the benefit of BMS by increasing the rate of target lesion revascularization (TLR) or target vessel revascularization (TVR). With the innovation of stent technology, drug-eluting stents (DES) designed to inhibit excessive neointimal growth was produced and anticipated to reduce the incidence of ISR. Indeed, the RAVEL trial (1), a double-blind randomized study comparing sirolimus-eluting stent with its non-coated counterpart, reported no restenosis in the sirolimus stent group, and 23.4% of the patient in the BMS group developed binary restenosis (P<0.001) at 6-month follow-up. Despite of these promising results, there’s still a certain proportion of ISR occurring after DES implantation due to the expansion of indications for PCI to complex coronary lesions in high-risk patients. Meanwhile, the advent of DES brought new challenges for the interventional cardiologists, such as the higher rate of late stent thrombosis and more bleeding events due to prolonged duration of dual anti-platelet therapy (DAPT). According to the type of stents previously implanted, ISR is classified as BMS ISR and DES ISR. As the literature (2,3) mentioned, 20% to 53% BMS ISR present as unstable angina and 3.5% to 20% as myocardial infarction (MI); The proportion of DES ISR manifesting as unstable angina and MI is 16% to 66% and 1% to 20% respectively. Given the clinical and prognostic importance of ISR, the debate on the optimal strategy to prevent and treat ISR is far from over.

CRT-146 In-Drug Eluting Stent Restenosis Treated By Paclitaxel Coated Balloon Angioplasty: Results From The French Prospective Garo Registry

The clinical benefits of paxlitaxel-coated balloon angioplasty (PCB) have been extensively studied in bare metal stent in-stent restenosis (BMS-ISR) and in drug eluting stent in-stent restenosis (DES-ISR). The GARO Registry is a dedicated ‘all comers’ study in an unselected patient population

Everolimus-eluting stent for the treatment of bare metal in-stent restenosis: clinical and angiographic outcomes at nine-month follow-up of XERES (Xience Evaluation in bare metal stent REStenosis) trial

Restenosis is a frequent complication of coronary stent implantation, especially bare metal stent (BMS) implantation. The everolimus-eluting stent (EES) has previously been shown to be efficacious in the treatment of de novo lesions. We performed this study to evaluate clinical, angiographic and IVUS results after EES implantation for the treatment of BMS ISR. XERES was a prospective, multicentre, nationwide study, enrolling 97 consecutive patients with in-stent restenosis (ISR) after BMS implantation across 20 centres in France. Suitable lesions had a reference vessel diameter between 2.5 mm and 4 mm, a length ≤22 mm and a diameter stenosis between 50 and 100%. The primary endpoint was angiographic in-stent late loss (LL) as determined by quantitative coronary angiography (QCA) at nine-month follow-up. QCA was required to be performed in each included patient and IVUS was performed in a subgroup of 27 patients. At nine-month follow-up, the in-stent late loss was 0.35±0.63 mm. The rate of in-stent binary restenosis was 12.22%, including two complete occlusions. The average volume of neointimal hyperplasia was 15.6±9.9 mm3. The in-stent percent volume obstruction was 8.5±5.2%. The in-segment percent area and diameter obstruction were 32±17% and 27±11%, respectively. Two initial malappositions were persistent and two other patients had late acquired stent malapposition. The cumulative incidence of major adverse cardiac events (MACE) was 10.1%. EES for the treatment of bare metal in-stent restenosis seemed safe and efficacious.

Optical coherence tomography study of healing characteristics of paclitaxel-eluting balloons vs. everolimus-eluting stents for in-stent restenosis: the SEDUCE (Safety and Efficacy of a Drug elUting balloon in Coronary artery rEstenosis) randomised clinical trial.

Little is known about the respective healing responses and clinical efficacy and safety of drug-eluting balloons (DEB) and the second generation of drug-eluting stents (DES) when used to treat in-stent restenosis (ISR). In this study, we set out to compare prospectively the healing characteristics, as assessed by optical coherence tomography (OCT), of DEB versus DES after treatment of ISR in bare metal stents (BMS). Fifty patients with BMS ISR were randomised to treatment with a paclitaxel-eluting balloon vs. an everolimus-eluting stent (EES). The primary endpoint was the percentage of uncovered struts, assessed with OCT at nine months, as a marker of vessel wall healing. A mean of 366±135 and 636±184 struts were analysed per patient in the DEB and EES groups, respectively. The percentage of uncovered struts per patient was significantly lower with DEB vs. EES (1.4% vs. 3.1%, p=0.025). Mean neointimal hyperplasia area was 2.4±1.08 mm in DEB vs. 1.92±0.67 mm in EES (p=0.1806), while the percentage of malapposed struts per patient was very low in both groups (0.2% vs. 0.3%, p=0.699). At nine months, angiographic in-stent MLD (minimum lumen diameter) was lower (2.13 vs. 2.54 mm, p=0.006), while diameter stenosis (26.4 vs. 11.4%, p=0.002), and LLL (0.28 vs. 0.07 mm, p=0.1) were higher after DEB compared to EES. During one-year follow-up, we did not observe differences in the rates of death, TLR (target lesion revascularisation) or stent thrombosis. DEB appears to be associated with better healing characteristics, as assessed by stent strut coverage with OCT, but tended to be slightly less effective compared to EES. These findings give support to the use of either DEB or EES as valuable treatment options for ISR. http://www.clinicaltrials.gov. Unique identifier: NCT 01065532.