Outcome differences with the use of drug-eluting stents for the treatment of in-stent restenosis of bare-metal stents versus drug-eluting stents

Drug-Eluting Stent Restenosis: Modern Approach to a Classic Challenge

In-stent restenosis (ISR) is a recognized complication following percutaneous coronary intervention in which the luminal diameter is narrowed through neointimal hyperplasia and vessel remodeling. Although rates of ISR have decreased in most recent years owing to newer generation drug-eluting stents, thinner struts, and better intravascular imaging modalities, ISR remains a prevalent dilemma that proves to be challenging to manage. Several factors have been proposed to contribute to ISR formation, including mechanical stent characteristics, technical factors during the coronary intervention, and biological aspects of drug-eluting stents. Presentation of ISR can range from asymptomatic to late myocardial infarction and could be difficult to differentiate from acute thrombus formation. No definite guidelines are present on the management of ISR. In this review, we will discuss the mechanisms underlying ISR and provide insight into patient-related and procedural risk factors contributing to ISR, in addition to highlighting common treatment approaches utilized in the management of ISR.

Comparison of Drug-Coated Balloon Angioplasty vs. Drug-Eluting Stent Implantation for Drug-Eluting Stent Restenosis in the Routine Clinical Practice: A Meta-Analysis of Randomized Controlled Trials

Introduction: In-stent restenosis (ISR) remains a challenging issue despite the great advance of drug-eluting stents (DES). In addition, the consensus was lacking regarding the optimal strategy for DES-ISR. Therefore, we aimed to evaluate angiographic and clinical outcomes of the two most effective treatments DES vs. drug-eluting balloon (DCB) for patients with DES-ISR. Methods: This meta-analysis used the data from the randomized controlled trials (RCTs), which were identified by a systematic search in the databases of PubMed, Embase, and Cochrane Library. Target lesion revascularization (TLR) was regarded as the primary endpoint. In addition, the late angiographic outcomes and other clinical outcomes, namely, cardiac death, myocardial infarction (MI), target vessel revascularization, stent thrombosis, and major adverse cardiac events, were also included for analysis. Results: Five RCTs with about 1,193 patients were included in this meta-analysis for the analysis. For the primary endpoint, the overall pooled outcomes suggested repeat DES implantation was associated with a significant reduction in the term of TLR compared with DCB angioplasty (risk ratio = 1.53, 95% CI 1.15-2.04, p = 0.003). But no significant difference in angiographic outcomes and other clinical endpoints were observed between DES and DCB. In the subgroup analysis, DCB was inferior to new-generation DES (NG-DES)/everolimus-eluting stent (EES) in the term of TLR. In addition, this non-significant trend was also noted in the subgroup of the paclitaxel-eluting stent (PES) vs. DCB. For the angiographic endpoints, EES, not PES, was associated with larger minimum lumen diameter [mean difference (MD) = -0.25, 95% CI -0.38 to -0.11, p = 0.0003], lower percent diameter stenosis (MD = 7.29%, 95% CI 2.86-11.71%, p = 0.001), and less binary restenosis (OR = 2.20, 95% CI 1.18-4.11, p = 0.01). But NG-DES/EES was comparable to DCB in cardiac death, MI, and stent thrombosis. Conclusions: For the patients with DES-ISR, treatment with DES, especially NG-DES/EES could reduce the risk of TLR significantly compared to DCB at long-term follow-up.

Impact of intravascular ultrasound on Outcomes following PErcutaneous coronary interventioN for In-stent Restenosis (iOPEN-ISR study)

BACKGROUND

Percutaneous coronary intervention (PCI) for in-stent restenosis (ISR) remains common. Intravascular imaging allows for the determination of the mechanism of ISR, potentially guiding appropriate therapy. Intravascular ultrasound (IVUS)-guided stent implantation is associated with a reduction in adverse events after PCI, but its impact on treatment of ISR is not clear.

METHODS

All patients with 1-year follow-up after ISR treatment from 2003 through 2016 were included and stratified by IVUS use. The primary endpoint was the rate of major adverse cardiac events (MACE) at 1 year, defined as the composite of all-cause mortality, Q-wave myocardial infarction, and target vessel revascularization (TVR).

RESULTS

The final analysis included 1522 ISR patients, 65.9% of whom were treated with IVUS guidance. The primary endpoint occurred in 18.0% of patients treated with IVUS guidance vs. 24.5% of patients treated with angiography guidance (p = 0.0014). Post-dilatation was used more often with IVUS (18.6% vs. 14.1%, p < 0.001), with a larger diameter of new stents (3.04 ± 0.35 mm vs. 2.94 ± 0.47 mm, p = 0.001). At 1 year, TVR occurred in 14.5% with IVUS guidance and 19.2% with angiography guidance (p = 0.021).

CONCLUSIONS

The use of IVUS is associated with decreased MACE at 1 year following PCI for ISR. These results support routine IVUS for the treatment of ISR lesions.

Effects of Danlou tablet for the treatment of stable angina pectoris: A study protocol of a randomized, double-blind, and placebo-controlled clinical trial

INTRODUCTION

Stable angina pectoris has a high prevalence and causes serious harm. Revascularization therapy can relieve angina pectoris to some extent, but it is not widely accepted in China due to the cost and secondary events. The Chinese proprietary medicine Danlou tablet has been widely used to treat angina pectoris, but previous trials had inadequate methodologies. In this study, we aim to conduct a randomized controlled trial to evaluate its efficacy and safety on stable angina.

METHODS AND ANALYSIS

This study is a WeChat-based randomized, double-blind, and placebo-controlled clinical trial in China. Eligible participants are adults (aged 30-75 years) with CT-confirmed stable angina and traditional Chinese medicine-diagnosed intermingled phlegm and blood stasis syndrome. A total of 76 participants will be randomly allocated in a 1:1 ratio to the oral Danlou tablet group (1.5 mg a time, 3 times daily for 28 days) or the placebo group. Patients are permitted concomitant use of routine medications during these 28 days. The primary outcome is angina frequency per week. The secondary outcomes include angina severity, angina duration, traditional Chinese medicine efficacy, the withdrawal rate of emergency medications, blood lipids, and electrocardiograph efficacy. The WeChat app will be used to remind patients to take their medicines and fill out the forms. All data will be recorded in case report forms and analyzed by Statistical Analysis System software.

ETHICS AND DISSEMINATION

This study has been approved by the Ethics Committee of Guang'anmen Hospital, China Academy of Chinese Medical Sciences in Beijing, China (No. 2019-225-KY).

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, ID: ChiCTR1900028068.

Differences in clinical outcomes between pre- and post-marketing clinical study following paclitaxel-coated balloon catheter treatment for coronary in-stent restenosis: from the Japanese regulatory viewpoint

In 2013, a drug-coated balloon catheter (DCB) (SeQuent Please) for the treatment of coronary in-stent restenosis (ISR) was approved in Japan. The pre-marketing Japan domestic NP001 study demonstrated better outcomes of the DCB (n = 138) compared to plain balloon angioplasty (n = 72). After the introduction to marketing, a post-marketing surveillance (PMS) (n = 396) was conducted to evaluate the safety and efficacy of the DCB in Japanese routine clinical practice. The aim of this paper was to assess differences between the pre-marketing NP001 study and the PMS. Compared to the NP001 study, more complex lesions were treated in the PMS (type B2/C: 69.0% vs 20.4%, total occlusion: 11.2% vs 0%, p < 0.001, respectively) and target lesion was more frequently ISR related to drug-eluting stent (DES) (79.5% vs 39.4%, p < 0.001). Regarding clinical outcomes, the rate of target lesion revascularization (TLR) was higher in the PMS than in the NP001 study (TLR: 12.9% at 7 months and 17.6% at 12 months vs 2.8% at 6 months, p = 0.001, p < 0.001, respectively). Multivariable logistic regression analysis revealed that DES-ISR was a risk factor of TLR after DCB treatment for ISR (odds ratio: 5.77, 95% CI 1.75-18.95, p = 0.004). Among representative published trials using DCB for ISR, clinical outcomes are often worse in DES-ISR trials than those in bare metal stent-ISR trials. The rates of TLR in previous DES-ISR trials are similar to that in the current PMS (TLR at 12 months: 22.1% for ISAR-DESIRE 3, 15.3% for PEPCAD-DES, and 13.0% for RIBS IV). The effectiveness and safety of DCB for coronary ISR have been confirmed in the Japanese real-world survey. PMS would be useful to evaluate the safety and effectiveness of medical products throughout their total life cycles.

Clinical Outcomes of Drug-Eluting versus Bare-Metal In-Stent Restenosis after the Treatment of Drug-Eluting Stent or Drug-Eluting Balloon: A Systematic Review and Meta-Analysis

Background

Although drug-eluting stents (DES) have reduced the rates of in-stent restenosis (ISR) compared with bare-metal stents (BMS), DES related ISR (DES-ISR) still occurs and outcomes of DES-ISR remain unclear. The objective of this meta-analysis was to investigate the long-term clinical outcomes of patients with DES-ISR compared with patients with BMS related ISR (BMS-ISR) after the treatment of DES or drug-eluting balloon (DEB). Methods and results. We searched the literature in the main electronic databases including PUBMED, EMBASE, Cochrane Library, and Web of Science. The primary endpoints were target lesion revascularization (TLR) and target vessel revascularization (TVR). The secondary endpoints included all cause death (ACD), cardiac death (CD), myocardial infarction (MI), stent thrombosis or re-in-stent restenosis (ST/RE-ISR), and major adverse cardiovascular events (MACEs). A total of 19 studies with 6256 participants were finally included in this meta-analysis. Results showed that the rates of TLR (P < 0.00001), TVR (P < 0.00001), CD (P=0.02), ST/RE-ISR (P < 0.00001), and MACEs (P < 0.00001) were significantly higher in the DES-ISR group than in the BMS-ISR group. No significant differences were found between the two groups in the rates of MI (P=0.05) and ACD (P=0.21).

Conclusions

Our study demonstrated that patients with DES-ISR had worse clinical outcomes at the long-term follow-up than patients with BMS-ISR after the treatment of DES or DEB, suggesting that DES and DEB may be more effective for BMS-ISR than that for DES-ISR. Positive prevention of DES-ISR is indispensable and further studies concentrating on detecting the predictors of outcomes of DES-ISR are required.

Combined Vascular Brachytherapy and Stenting for the Treatment of In-Stent Restenosis

In-stent restenosis (ISR) remains a therapeutic challenge in the current drug-eluting stent (DES) era. Vascular brachytherapy (VBT) is a therapeutic option for ISR, but data about the outcomes of combination therapy with VBT and stenting for ISR lesions are sparse. We retrospectively analyzed patients who presented with ISR at our institution from 2003 through 2017. Three treatment arms were compared: VBT alone, VBT plus bare-metal stent (BMS), and VBT plus DES. Clinical, procedural, and 1-year outcome data were collected. Follow-up was obtained by phone calls and clinic visits. The patient cohort included 461 patients (764 ISR lesions). Of these, 333 patients (533 lesions) were treated with VBT alone, 89 patients (158 lesions) with VBT plus BMS, and 39 patients (73 lesions) with VBT plus DES. There were no significant differences in baseline characteristics among the 3 groups except for more patients with a remote smoking history in the VBT plus BMS (43.8%) and VBT plus DES groups (56.4%), and more patients with history of peripheral vascular disease (39.5%) and congestive heart failure (27%) in the VBT plus DES group. The most common clinical presentation was unstable angina (64.6%). In the VBT plus DES group, 10.3% of patients presented with MI, versus 5.5% in the VBT alone group and 2.2% in the VBT plus BMS group. At 1-year follow-up, the VBT plus DES group had higher rates of target vessel revascularization-major adverse cardiovascular events (38.5%) than the VBT plus BMS (21.3%) and VBT alone (15.6%) groups (p = 0.002). In conclusion, in patients with ISR, combination therapy with VBT and stenting at the same setup is associated with worse outcomes at 12 months and, if possible, should be avoided.

Outcomes of intravascular brachytherapy for recurrent drug-eluting in-stent restenosis

OBJECTIVES

To examine the outcomes of vascular brachytherapy (VBT) for recurrent drug-eluting stents (DES) in-stent restenosis (ISR).

BACKGROUND

Recurrent DES-ISR can be challenging to treat. VBT has been used with encouraging results.

METHODS

We report the long-term outcomes of patients with recurrent DES-ISR treated with VBT between January 2014 and September 2018 at a tertiary care institution. The main outcome was target lesion failure (TLF), defined as the composite of clinically driven target lesion revascularization (TLR), target lesion myocardial infarction (MI), and target lesion-related cardiac death. Cox proportional hazards analysis was performed to identify variables associated with recurrent TLF.

RESULTS

During the study period, 116 patients (143 lesions) underwent VBT. Median follow-up was 24.7 (14.5-35.4) months. The incidence of TLR, target-lesion MI, and TLF was 18.9%, 5.6%,and 20.1% at 1 year, and 29.4%, 10.5%, and 32.9% at 2 years.Initial presentation with acute coronary syndrome (ACS) was independently associated with TLF (hazard ratio = 1.975, 95% CI [1.120, 3.485], p = .019). Lesions treated with intravascular ultrasound (IVUS) guidance had a lower incidence of TLR (14.3% vs. 39.6%, log-rank p = .038), and a trend toward lower incidence of TLF (19% vs. 42.6%, log-rank p = .086).

CONCLUSIONS

VBT can improve the treatment of recurrent DES-ISR, but TLF occurs in approximately one in three patients at 2 years. Initial presentation with ACS was associated with higher TLF and the use of IVUS with a trend for lower incidence of TLF.

3-Year Clinical Follow-Up of the RIBS IV Clinical Trial: A Prospective Randomized Study of Drug-Eluting Balloons Versus Everolimus-Eluting Stents in Patients With In-Stent Restenosis in Coronary Arteries Previously Treated With Drug-Eluting Stents

OBJECTIVES

This study sought to compare the long-term safety and efficacy of drug-eluting balloons (DEB) and everolimus-eluting stents (EES) in patients with in-stent restenosis (ISR) of drug-eluting stents (DES).

BACKGROUND

Treatment of patients with DES-ISR remains a challenge.

METHODS

The RIBS IV (Restenosis Intra-Stent of Drug-Eluting Stents: Drug-Eluting Balloons vs Everolimus-Eluting Stents) trial is a prospective multicenter randomized clinical trial comparing DEB and EES in patients with DES-ISR. The pre-specified comparison of the 3-year clinical outcomes obtained with these interventions is the main objective of the present study.

RESULTS

A total of 309 patients with DES-ISR were randomized to DEB (n = 154) or EES (n = 155). At angiographic follow-up, the in-segment minimal lumen diameter was larger in the EES arm (2.03 ± 0.7 mm vs. 1.80 ± 0.6 mm; p < 0.01). Three-year clinical follow-up was obtained in all enrolled patients (100%). The combined clinical outcome measure of cardiac death, myocardial infarction and target lesion revascularization was significantly reduced in the EES arm (19 [12.3%] vs. 31 [20.1%]; p = 0.04; hazard ratio: 0.57 [95% confidence interval: 0.34 to 0.96]), driven by a lower need for target lesion revascularization (11 [7.1%] vs. 24 [15.6%]; p = 0.015; hazard ratio: 0.43 [95% confidence interval: 0.21 to 0.87]). The need for "late" (>1 year) target lesion revascularization (2.6% vs. 4%) and target vessel revascularization (4% vs. 6.6%) was similar in the 2 arms. Rates of cardiac death (3.9% vs. 3.2%), myocardial infarction (2.6% vs. 4.5%), and stent thrombosis (1.3% vs. 2.6%) at 3 years were also similar in both arms.

CONCLUSIONS

The 3-year clinical follow-up of this randomized clinical trial demonstrates that in patients with DES-ISR, EES reduce the need for repeat interventions compared with DEB. (Restenosis Intra-Stent of Drug-Eluting Stents: Drug-Eluting Balloons vs Everolimus-Eluting Stents [RIBS IV]; NCT01239940).

Intravascular Brachytherapy for the Management of Repeated Multimetal-Layered Drug-Eluting Coronary Stent Restenosis

BACKGROUND

Because of the widespread acceptance of percutaneous coronary intervention with drug-eluting stents as an effective treatment strategy for in-stent restenosis, it is common to encounter multimetal layer stent restenosis in the recent years. This study aimed to evaluate the clinical outcomes of such patients treated with intravascular brachytherapy (IVBT) in comparison with other percutaneous options.

METHODS AND RESULTS

We enrolled patients who underwent percutaneous coronary intervention during the period between 2011 and 2015 for recurrent drug-eluting stents in-stent restenosis with at least 2 layers of stents at the lesion site. This analysis compared patients who underwent treatment with IVBT and those who did not (non-IVBT group). The primary end point measured was major adverse cardiac events defined as a composite of target lesion revascularization, myocardial infarction, and all-cause mortality at 12 months. Adjusted associations were measured using propensity score matching. A total of 328 percutaneous coronary intervention patients met the eligibility criteria, of which 197 patients received IVBT, and 131 patients underwent routine percutaneous intervention. The primary end point was significantly lower in patients undergoing IVBT (13.2% and 28.2%; P=0.01). A propensity score matching for risk factors of in-stent restenosis identified 182 patients. The advantages of IVBT with regard to 1-year major adverse cardiac events were confirmed in this matched cohort (13.2% and 30.8%; adjusted hazard ratio [95% CI]: 0.37 [0.18-0.73]; P<0.01).

CONCLUSIONS

In this analysis, IVBT led to significantly lower major adverse cardiac events in patients with multilayered drug-eluting stents restenosis when compared with other percutaneous options at 1-year follow-up.

The effect of the debulking by excimer laser coronary angioplasty on long-term outcome compared with drug-coating balloon: insights from optical frequency domain imaging analysis

This study evaluated the 1-year efficacy of excimer laser coronary angioplasty (ELCA) before drug-coated balloon (DCB) dilatation for the treatment of in-stent restenosis (ISR). Forty consecutive patients with ISR were treated by DCB with or without the use of ELCA (ELCA plus DCB, N = 20; DCB alone, N = 20). Debulking efficiency (DE) value was defined as the neointima area on optical frequency domain imaging (OFDI) debulked by ELCA. The patients in the ELCA plus DCB group were divided into two groups (greater DE (GDE), N = 10; smaller DE (SDE), N = 10) based on the median value of DE. Thereafter, the ISR segment was prepared with a scoring balloon, followed by DCB. At follow-up, binary restenosis and target lesion revascularization (TLR) were evaluated. There were no significant differences in baseline characteristics such as age, comorbidity, and ISR type. Overall, the incidence of neoatherosclerosis in the ISR segment was 17.5%. Post-PCI, acute gain of minimum lumen diameter on quantitative coronary angiography and of minimum lumen area on OFDI was numerically higher in the GDE than in the SDE and the DCB alone group. At follow-up, the occurrences of binary restenosis and TLR in the ELCA plus DCB group were 20.0% and 10.0%; these values in the DCB alone group were 20.0% and 20.0%, respectively. Two patients from the SDE and none from the GDE developed TLR. DCB alone treatment was inferior to ELCA plus DCB treatment. However, greater ELCA debulking might be required to obtain optimal outcomes.

Interventional cardiology: from balloons to stents … and back?

The treatment of coronary artery disease has seen rapid change following the invention of percutaneous coronary intervention (PCI). Since its introduction and widespread adoption for the treatment of coronary artery disease, efforts have been underway to minimise both the acute and long-term complications associated with the procedures, resulting in varying degrees of success over the years. These measures have taken many forms, from the adjunctive drug treatment regimen that patients receive before, during and after procedures to the actual mechanical intervention to the vessels themselves. The current gold standard in the interventional field is second-generation drug-eluting stents. However, with ongoing research into new technologies and trials underway in absorbable and non-stent treatments, it may soon be possible to achieve the goal of leaving no long-term physical implant behind in the artery. This could overcome issues with inflammation associated with permanent foreign body implants and prove less limiting for future treatment if needed.

Neointimal Modification With Scoring Balloon and Efficacy of Drug-Coated Balloon Therapy in Patients With Restenosis in Drug-Eluting Coronary Stents: A Randomized Controlled Trial

OBJECTIVES

The aim of this study was to compare neointimal modification with scoring balloon pre-dilation before drug-coated balloon (DCB) versus DCB standard therapy in patients presenting with drug-eluting stent (DES) restenosis.

BACKGROUND

DCB angioplasty for the treatment of coronary drug-eluting stent restenosis has demonstrated encouraging results. The efficacy of DCB treatment relies on rapid initial drug transfer and tissue retention of the antiproliferative drug. Neointimal modification with scoring balloon pre-dilation may enhance the efficacy of DCB therapy.

METHODS

In this randomized, open-label, active-controlled trial, 252 patients with clinically significant DES restenosis were enrolled at 4 centers in Germany. Patients undergoing DCB angioplasty were randomly assigned to treatment with scoring balloon pre-dilation or standard therapy. The primary endpoint of the study was in-segment percentage diameter stenosis on 6- to 8-month follow-up angiography. The secondary endpoints included binary angiographic restenosis and late lumen loss on follow-up angiography, the combined incidence of death or myocardial infarction, target lesion revascularization, and target lesion thrombosis at 1 year.

RESULTS

Follow-up angiographic data at 6 to 8 months were available for 203 patients (80.6%). Scoring balloon pre-dilation compared with standard therapy showed significantly lower rates with respect to the primary endpoint (35.0 ± 16.8% vs. 40.4 ± 21.4%; p = 0.047) and binary angiographic restenosis (18.5% vs. 32.0%; p = 0.026). Late lumen loss was numerically lower after scoring balloon pre-dilation compared with standard therapy (0.31 ± 59 mm vs. 0.41 ± 0.74 mm; p = 0.27). There was no difference between the groups in the incidence of death or myocardial infarction (4.0% vs. 3.4%; p = 0.73). Scoring balloon versus standard therapy showed comparable rates of target lesion revascularization (16.2% vs. 21.8%; p = 0.26). No target lesion thrombosis occurred out to 1 year.

CONCLUSIONS

In patients presenting with drug-eluting stent restenosis, neointimal modification with scoring balloon improves the antirestenotic efficacy of DCB therapy. (Intracoronary Stenting and Angiographic Results: Optimizing Treatment of Drug Eluting Stent In-Stent Restenosis 4 [ISAR-DESIRE 4]; NCT01632371).

Percutaneous coronary intervention of lesions with in-stent restenosis: A report from the ADAPT-DES study

BACKGROUND

There is a paucity of data from large contemporary cohorts of patients with in-stent restenosis (ISR) treated with drug-eluting stents (DESs), and no studies have examined the impact of high platelet reactivity (HPR) on the occurrence of ischemic events after ISR percutaneous coronary intervention (PCI) with DESs. We sought to report outcomes after PCI of ISR lesions and its association with HPR.

METHODS

Patients in the prospective, multicenter ADAPT-DES study were stratified according to whether they had ISR versus non-ISR PCI. Two-year outcomes were compared between the groups using Cox proportional hazards models. HPR was defined as on-clopidogrel P2Y12 platelet reaction units >208 as measured by the VerifyNow assay; target vessel failure (TVF) was defined as the composite of all-cause death, myocardial infarction, or ischemia-driven target vessel revascularization.

RESULTS

Among the 8,582 patients included in the ADAPT-DES study, 840 (9.8%) patients underwent successful ISR PCI. ISR PCI was independently associated with a higher 2-year risk of TVF (adjusted hazard ratio [HR] 1.95; 95% CI 1.68-2.27; P<.001) and stent thrombosis (adjusted HR 1.95; 95% CI 1.08-3.51; P=.027) but not bleeding (adjusted HR 0.94; 95% CI 0.73-1.21; P=.64). There was no statistical interaction between HPR and ISR versus non-ISR PCI in regard to TVF (adjusted P_interaction=.81).

CONCLUSIONS

ISR PCI is associated with a considerably higher risk of 2-year adverse ischemic events, with HPR conferring similar risk in ISR and non-ISR PCI. More effective therapeutic strategies for managing ISR lesions are necessary.

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

BACKGROUND

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.

METHODS AND RESULTS

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.

CONCLUSIONS

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.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01239953 and NCT01239940.

Optimizing endothelial cell functionalization for cell therapy of vascular proliferative disease using a direct contact co-culture system

Increased susceptibility to thrombosis, neoatherosclerosis, and restenosis due to incomplete regrowth of the protective endothelial layer remains a critical limitation of the interventional strategies currently used clinically to relieve atherosclerotic obstruction. Rapid recovery of endothelium holds promise for both preventing the thrombotic events and reducing post-angioplasty restenosis, providing the rationale for developing cell delivery strategies for accelerating arterial reendothelialization. The successful translation of experimental cell therapies into clinically viable treatment modalities for restoring vascular endothelium critically depends on identifying strategies for enhancing the functionality of endothelial cells (EC) derived from high cardiovascular risk patients, the target group for the majority of angioplasty procedures. Enhancing EC-associated nitric oxide (NO) synthesis by inducing overexpression of NO synthase (NOS) has shown promise as a way of increasing paracrine activity and restoring function of EC. In the present study, we developed a direct contact co-culture approach compatible with highly labile effectors, such as NO, and applied it for determining the effect of EC functionalization via NOS gene transfer on the growth of co-cultured arterial smooth muscle cells (A10 cell line) exhibiting the defining characteristics of neointimal cells. Bovine aortic endothelial cells magnetically transduced with inducible NOS-encoding adenovirus (Ad) formulated in zinc oleate-based magnetic nanoparticles (MNP[_iNOSAd]) strongly suppressed growth of proliferating A10 and attenuated the stimulatory effect of a potent mitogen, platelet-derived growth factor (PDGF-BB), whereas EC functionalization with free _iNOSAd or MNP formulated with a different isoform of the enzyme, endothelial NOS, was associated with lower levels of NO synthesis and less pronounced antiproliferative activity toward co-cultured A10 cells. These results show feasibility of applying magnetically facilitated gene transfer to potentiate therapeutically relevant effects of EC for targeted cell therapy of restenosis. The direct contact co-culture methodology provides a sensitive and reliable tool with potential utility for a variety of biomedical applications.

Usefulness of Drug-Eluting Balloons for Bare-Metal and Drug-Eluting In-Stent Restenosis (from the RIBS IV and V Randomized Trials)

Treatment of patients with drug-eluting stent (DES) in-stent restenosis (ISR) is particularly challenging. We sought to compare results of drug-eluting balloons in patients with DES-ISR with those in patients with bare-metal stent (BMS) ISR. A pooled analysis of the Restenosis Intra-Stent: Drug-Eluting Balloon versus Everolimus-Eluting Stent IV and V randomized trials was performed. Both trials had identical inclusion and exclusion criteria. Results of drug-eluting balloons in 95 patients with BMS-ISR and 154 patients with DES-ISR were compared. Patients with DES-ISR were more frequently diabetics, presented more often as an acute coronary syndrome and had more severe lesions and more frequently a focal pattern, including edge-ISR. Late angiographic findings (92% of eligible patients), including minimal lumen diameter (1.80 ± 0.6 vs 2.01 ± 0.6 mm, p = 0.001; absolute mean difference 0.21 mm; 95% confidence interval 0.04 to 0.38; p = 0.014) and restenosis rate (19% vs 9.5%, p <0.05) were poorer in DES-ISR. Results were consistent across 10 prespecified subgroups. Moreover, on multiple linear regression analysis, minimal lumen diameter at follow-up remained significantly smaller in patients with DES-ISR after adjusting for potential confounders (adjusted absolute mean difference 0.17 mm; 95% confidence interval 0.04 to 0.41; p = 0.019). Finally, at 1-year clinical follow-up (100% of patients), rates of target vessel revascularization (16% vs 6%, p = 0.02) and of the main combined clinical end point (18% vs 8%, p = 0.03) were significantly higher in patients treated for DES-ISR. In conclusion, this study confirms the efficacy of DEB for patients with ISR. However, the long-term clinical and angiographic results of DEB are poorer in patients with DES-ISR than in those with BMS-ISR. (ClinicalTrials.govIdentifier:NCT01239953&NCT01239940).

Randomised, double-blind, placebo-controlled study investigating the effects of inorganic nitrate on vascular function, platelet reactivity and restenosis in stable angina: protocol of the NITRATE-OCT study

INTRODUCTION

The mainstay treatment for reducing the symptoms of angina and long-term risk of heart attacks in patients with heart disease is stent implantation in the diseased coronary artery. While this procedure has revolutionised treatment, the incidence of secondary events remains a concern. These repeat events are thought to be due, in part, to continued enhanced platelet reactivity, endothelial dysfunction and ultimately restenosis of the stented artery. In this study, we will investigate whether a once a day inorganic nitrate administration might favourably modulate platelet reactivity and endothelial function leading to a decrease in restenosis.

METHODS AND DESIGN

NITRATE-OCT is a double-blind, randomised, single-centre, placebo-controlled phase II trial that will enrol 246 patients with stable angina due to have elective percutaneous coronary intervention procedure with stent implantation. Patients will be randomised to receive 6 months of a once a day dose of either nitrate-rich beetroot juice or nitrate-deplete beetroot juice (placebo) starting up to 1 week before their procedure. The primary outcome is reduction of in-stent late loss assessed by quantitative coronary angiography and optical coherence tomography at 6 months. The study is powered to detect a 0.22±0.55 mm reduction in late loss in the treatment group compared with the placebo group. Secondary end points include change from baseline assessment of endothelial function measured using flow-mediated dilation at 6 months, target vessel revascularisation (TVR), restenosis rate (diameter>50%) and in-segment late loss at 6 months, markers of inflammation and platelet reactivity and major adverse cardiac events (ie, myocardial infarction, death, cerebrovascular accident, TVR) at 12 and 24 months.

ETHICS AND DISSEMINATION

The study was approved by the Local Ethics Committee (15/LO/0555). Trial results will be published according to the CONSORT statement and will be presented at conferences and reported in peer-reviewed journals.

TRIAL REGISTRATION NUMBERS

NCT02529189 and ISRCTN17373946, Pre-results.

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

BACKGROUND

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.

METHODS AND RESULTS

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).

CONCLUSIONS

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.

Late Restenosis After Both First-Generation and Second-Generation Drug-Eluting Stent Implantations Occurs in Patients With Drug-Eluting Stent Restenosis

Background—

There are currently inadequate data about whether late restenosis occurs after drug-eluting stent (DES) implantation in patients with DES restenosis.

Methods and Results—

We collected data for 608 patients who received revascularization for DES restenosis between 2004 and 2012 and analyzed 688 lesions: 359 lesions treated with a first-generation DES (first DES) and 329 lesions treated with a second-generation DES (second DES). Two serial angiographic follow-ups were routinely planned for the patients (at 8 and 20 months after the procedure). Early follow-up angiography was performed for 620 lesions (90.1%), and recurrent restenosis occurred in 84 lesions (25.8%) in the first DES group and in 72 lesions (24.5%) in the second DES group ( P =0.78). Target lesion revascularization was performed for 69 lesions (21.2%) in the first DES group and for 48 lesions (16.3%) in the second DES group ( P =0.15). Late follow-up angiography was performed for 438 (87.1%) of the remaining 503 lesions (excluding target lesion revascularization lesions), and late restenosis was found in 35 lesions (15.8%) in the first DES group and in 28 lesions (14.7%) in the second DES group ( P =0.79). Nonfocal-type restenosis, percentage diameter stenosis after the procedure, previous stent size ≤2.5 mm, and right coronary artery ostial lesion were independent predictors of early restenosis. Nonfocal-type restenosis, percentage diameter stenosis at early follow-up, and stent fracture were independent predictors of late restenosis.

Conclusions—

Late restenosis occurs after both first DES implantation and second DES implantation for DES restenosis.

Drug-eluting stents or balloon angioplasty for drug-eluting stent-associated restenosis: An observational follow-up study of first-time versus repeated restenosis

BACKGROUND

The treatment of patients with repeated drug-eluting stent-in stent restenosis (DES-ISR) remains a challenge and a burdensome clinical problem.

METHODS

Over a 3-year period, 130 lesions in 123 patients who underwent target lesion revascularization (TLR) for DES restenosis were included in the study. They were classified into two main groups: the first group having first-time DES-ISR (n = 84), and the second group having rerestenosis of DES-treated DES-ISR (n = 39). Further classification according to the treatment strategy yielded four subgroups: balloon angioplasty (BA) in first-time DES-ISR (n = 66), re-DES in the same group (n = 22), BA in rerestenosis of DES-treated DES-ISR (n = 30), and re-DES in the same group (n = 10). Angiographic follow-up was planned at 1 year, and clinical follow-up for re-TLR up to 2 years later.

RESULTS

The mean duration of clinical follow-up was 24.8 ± 9.7 months. The angiographic follow-up data were obtained for 108 patients (87.8%) at 1 year. Among patients treated for first-time DES-ISR, late lumen loss (0.65 ± 0.83 mm and 1.02 ± 0.52 mm, p = 0.02) and binary restenosis rates (25% and 49.1%, p = 0.05) were significantly less in those undergoing re-DES compared with BA. This benefit was not evident in patients having rerestenosis of DES-treated DES-ISR. Re-TLR at 2 years was significantly less in the re-DES group compared with BA (log rank p = 0.038) in first-time DES-ISR patients, while no significant difference (log rank p = 0.58) was observed in those having rerestenosis of DES-treated DES-ISR.

CONCLUSION

While a strategy of re-DES would be better than BA in first-time DES-ISR, this could not be extrapolated to rerestenosis cases.

Drug Coated Balloon Is Less Effective for Treatment of DES In-Stent Restenosis Both in Native Coronary Arteries and Saphenous Vein Grafts: Results From a Bicenter Registry

BACKGROUND

The paclitaxel drug coated balloon (DCB) is an established treatment for bare metal stent (BMS) in-stent restenosis (ISR) in native coronary arteries. The evidence of DCB-application for drug eluting stent (DES) ISR both in native coronaries and saphenous vein grafts (SVG) is limited. Aim of our study was to compare the differential efficacy of DCB for treatment of BMS- and DES-ISR in native coronary vessels and SVGs.

METHODS AND RESULTS

N = 135 DCB-treated patients with available follow up (FU) angiography were included in this retrospective study. Patients received treatment between April 2009 and March 2013 at 2 tertiary care hospitals in Germany. DCB was applied in BMS-ISR (n = 65; 48%) and DES-ISR (n = 70; 52%). DCB-treated lesions were located in native coronary arteries (n = 110; 81%; BMS-ISR: n = 58; 53%; DES-ISR: n = 52; 47%) and SVGs (n = 25; 19%; BMS-ISR: n = 7, 28%; DES-ISR: n = 18, 72%). Median FU was 12 months. Endpoints were binary restenosis and target lesion revascularization (TLR). Binary restenosis (29% vs. 57%; P < 0.01) and TLR (18% vs. 46%; P < 0.01) were significantly more frequent in DES-ISR versus BMS-ISR. In SVGs, TLR was required in 72% (DES-ISR) versus 14% (BMS-ISR); P = 0.02. In the Kaplan-Meier-analysis freedom from both endpoints was significantly decreased in the DES-lesions both in the total population (binary restenosis P < 0.01; TLR P < 0.01) and native coronaries (binary restenosis P = 0.02; TLR P = 0.04).

CONCLUSIONS

DCB treatment is less effective in DES-ISR than in BMS-ISR. The diminished efficacy of DCB treatment is even more pronounced in DES-ISR located within degenerated SVGs.

Impaired Peripheral Endothelial Function Assessed by Digital Reactive Hyperemia Peripheral Arterial Tonometry and Risk of In-Stent Restenosis

Background

Drug‐eluting stents are replacing bare‐metal stents, but in‐stent restenosis (ISR) remains a problem. Reactive hyperemia index (RHI) assessed by peripheral arterial tonometry evaluates endothelial function noninvasively. We prospectively assessed the prognostic value of RHI in predicting ISR after percutaneous coronary intervention.

Methods and Results

RHI was measured before percutaneous coronary intervention and at follow‐up (F/U) angiography (F/U RHI; 6 and 9 months post bare‐metal stents– and drug‐eluting stents– percutaneous coronary intervention, respectively) in 249 consecutive patients. At F/U, ISR (stenosis >50% of diameter) was seen in 68 patients (27.3%). F/U natural logarithm (RHI) was significantly lower in patients with ISR than in those without (0.52±0.23 versus 0.65±0.27, P<0.01); no between‐group difference in initial natural logarithm (RHI) (0.60±0.26 versus 0.62±0.25, P=0.56) was seen. By multivariate logistic regression analysis, even after adjusting for other significant parameters in univariate analysis, F/U natural logarithm (RHI) independently predicted ISR (odds ratio: 0.13; 95% CI: 0.04–0.48; P=0.002). In receiver operating‐characteristic analysis, F/U RHI was the strongest predictor of ISR (area under the curve: 0.67; 95% CI: 0.60–0.75; P<0.01; RHI <1.73 had 67.6% sensitivity, 64.1% specificity); area under the curve significantly improved from 0.62 to 0.70 when RHI was added to traditional ISR risk factors (P=0.02). Net reclassification index was significant after addition of RHI (26.5%, P=0.002).

Conclusions

Impaired RHI at F/U angiography independently correlated with ISR, adding incremental prognostic value to the ISR‐risk stratification following percutaneous coronary intervention.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov/. Unique identifier: NCT02131935.

Same or Different Drug-Eluting Stent Re-Implantation for Drug-Eluting Stent Restenosis: An Assessment Including Second-Generation Drug-Eluting Stents

OBJECTIVES

We examined the long-term outcomes of implanting a different type of drug-eluting stent (DES), including second-generation DES, for treatment of DES-in stent restenosis (ISR).

BACKGROUND

Treatment for DES-ISR has not been standardized.

METHODS

The subjects were 80 patients with 89 lesions underwent DES implantation for DES-ISR. The patients were divided into the group of patients receiving the same DES for DES-ISR (Homo-stent: 24 patients, 25 lesions) and a different DES for DES-ISR (Hetero-stent: 56 patients, 64 lesions). The primary endpoint was survival free of major adverse cardiovascular events (MACE), including cardiac death, myocardial infarction, and target vessel revascularization (TVR). The secondary endpoint was late loss at 8-12 months follow-up. In the subgroup of patients who were treated with second-generation DES for DES-ISR, we also assessed the survival free of MACE.

RESULTS

During a mean follow-up of 45.1 ± 21.2 months, 26 patients experienced MACE. There was no significant difference in the survival free of MACE (Log rank P = 0.17). In the sub-analysis of second generation DES, MACE was significantly higher in the Homo-stent group compared to the Hetero-stent group (Log rank P = 0.04). Late loss was significantly higher in the Homo-stent group than in the Hetero-stent group (0.86 ± 1.03 vs. 0.38 ± 0.74 mm, P = 0.03). This trend was prominent in the first-generation DES group.

CONCLUSIONS

Although there was no significant difference in MACE between the Hetero-stent and the Homo-stent groups including both first and second-generation DES, the sub-analysis demonstrated different DES implantation for DES-ISR significantly improved the MACE rate among patients treated with second-generation DES. (J Interven Cardiol 2016;29:311-318).

Ten-year clinical outcomes after sirolimus-eluting stent implantation: Impact of an in-stent restenosis target lesion

Little is known about the long-term outcomes after first-generation sirolimus-eluting stent (SES) implantation. We aimed to investigate the clinical outcomes up to 10 years after SES implantation.

METHODS

The study population comprised 342 patients (504 lesions) who underwent SES implantation between January 2002 and December 2004. The median duration of follow-up was 3816 days (interquartile range [Q1-Q3], 3,705-3,883 days).

RESULTS

The cumulative event rate of definite stent thrombosis was 3.9%. The cumulative rate of target lesion revascularization (TLR) at 1, 5, and 10 years was 8.7%, 18.8%, and 31.1%, respectively, and the annual rate of TLR was 3.1%. Clinically driven TLR occurred at relatively constant rate during 10 years (2.0% per year). In a multivariate analysis, higher body mass index, hemodialysis, in-stent restenosis (ISR) target lesion, and total stent length >30 mm were independent risk factors of TLR within 5 years. An independent risk factor of TLR beyond 5 years was ISR target lesion.

CONCLUSIONS

Late TLR after SES implantation is a long-term hazard, lasting up to 10 years. The ISR target lesion is a risk factor of TLR during 10 years.

Comparison of the Efficacy of Everolimus-Eluting Stents Versus Drug-Eluting Balloons in Patients With In-Stent Restenosis (from the RIBS IV and V Randomized Clinical Trials)

Treatment of patients with in-stent restenosis (ISR) remains a challenge. This study sought to compare the efficacy of everolimus-eluting stents (EESs) and drug-eluting balloons (DEBs) with paclitaxel in patients with ISR. A pooled analysis of the Restenosis Intra-Stent of Drug-Eluting Stents: Drug-Eluting Balloon vs Everolimus-Eluting Stent (RIBS IV) and Restenosis Intra-Stent of Bare-Metal Stents: Drug-Eluting Balloon vs Everolimus-Eluting Stent (RIBS V) randomized trials was performed using patient-level data. In both trials, EESs were compared with DEBs in patients with ISR (RIBS V included 189 patients with bare-metal ISR; RIBS IV included 309 patients with drug-eluting ISR). Inclusion and exclusion criteria were identical in both trials. A total of 249 patients were allocated to EES and 249 to DEB. Clinical follow-up at 1 year was obtained in all (100%) patients and late angiography (median 249 days) in 91% of eligible patients. Compared with patients treated with DEBs, patients treated with EESs obtained better short-term results (postprocedural minimal lumen diameter 2.28 ± 0.5 vs 2.12 ± 0.4 mm, p <0.0001). At follow-up, patients treated with EESs had larger in-segment minimal lumen diameter (primary end point 2.16 ± 0.7 vs 1.88 ± 0.6 mm, p <0.0001; absolute mean difference 0.28 mm; 95% confidence interval [CI] 0.16 to 0.40) and net lumen gain (1.33 ± 0.6 vs 1.00 ± 0.7 mm, p <0.0001) and had lower %diameter stenosis (19 ± 21% vs 28 ± 22%, p <0.0001) and binary restenosis rate (8.7% vs 15.7%, p = 0.02). Consistent results were observed in the in-lesion analysis. No interactions were found between the underlying stent type and treatment effects. At 1-year clinical follow-up, the composite of cardiac death, myocardial infarction, and target vessel revascularization was significantly reduced in the EES arm (8.8% vs 14.5%, p = 0.03; hazard ratio 0.59, 95% CI 0.31 to 0.94) mainly driven by a lower need for target vessel revascularization (6% vs 12.4%, p = 0.01, hazard ratio 0.46, 95% CI 0.25 to 0.86). This pooled analysis of the RIBS IV and RIBS V randomized trials demonstrates the superiority of EES over DEB in the treatment of patients with ISR.

Management of drug eluting stent in-stent restenosis: A systematic review and meta-analysis

BACKGROUND

The optimal management for coronary drug eluting stent in-stent restenosis (DES ISR) is unclear. We performed a meta-analysis of observational and randomized studies to compare the outcomes of management of DES ISR using DES, drug eluting balloon (DEB), or balloon angioplasty (BA).

METHODS

Eligible studies (25 single arm and 13 comparative, including 4 randomized studies with a total of 7,474 patients with DES ISR) were identified using MEDLINE search and proceedings of international meetings. Outcomes studied include major adverse cardiac events (MACE), target lesion revascularization (TLR), target vessel revascularization (TVR), myocardial infarction (MI), stent thrombosis (ST), and mortality. Follow-up ranged from 0.5 to 3.5 years (mean 1.4 years).

RESULTS

The rate of TLR was significantly lower in the DES (odds ratio [OR] 0.50, 95% confidence interval [CI] 0.36-0.69) and DEB (OR 0.31, 95% CI 0.18-0.55) groups compared to BA. Similarly, TVR rate was significantly lower in the DES (OR 0.55, 95% CI 0.39-0.77) and DEB (OR 0.32, 95% CI 0.18-0.58) groups compared to BA. All other outcomes were similar between the DES/BA and DEB/BA comparisons. TLR was significantly lower in the DES group compared to BA for vessels < or > 2.75 mm.

CONCLUSION

Treatment of coronary DES ISR with DES or DEB is associated with a reduction in the risk of TLR and TVR compared to BA alone. The relative risk reduction for TLR with DES is similar to DEB. DEBs have a potential role in the treatment of DES ISR by avoiding placement of another layer of stent. © 2015 Wiley Periodicals, Inc.

Cost-effectiveness modelling of percutaneous coronary interventions in stable coronary artery disease

The objective of this study is to develop a cost-effectiveness model comparing drug eluting stents (DES) vs bare metal stent (BMS) in patients suffering of stable coronary artery disease. Using a 2-years time horizon, two simulation models have been developed: BMS first line strategy and DES first line strategy. Direct medical costs were estimated considering ambulatory and hospital costs. The effectiveness endpoint was defined as treatment success, which is the absence of major adverse cardiac events. Probabilistic sensitivity analyses were carried out using 10000 Monte-Carlo simulations. DES appeared slightly more efficacious over 2 years (60% of success) when compared to BMS (58% of success). Total costs over 2 years were estimated at 9303 € for the DES and at 8926 € for bare metal stent. Hence, corresponding mean cost-effectiveness ratios showed slightly lower costs (P < 0.05) per success for the BMS strategy (15520 €/success), as compared to the DES strategy (15588 €/success). Incremental cost-effectiveness ratio is 18850 € for one additional percent of success. The sequential strategy including BMS as the first option appears to be slightly less efficacious but more cost-effective compared to the strategy including DES as first option. Future modelling approaches should confirm these results as further comparative data in stable coronary artery disease and long-term evidence become available.

Paclitaxel-coated balloons for the treatment of patients with in-stent restenosis: A meta-analysis of angiographic and clinical data

Paclitaxel-coated balloons (PCBs) have become attractive alternative treatment options for patients with in-stent restenosis (ISR); however, the safety and efficacy of PCBs in comparison with those of conventional therapies are less well defined. The aim of this meta-analysis was to systematically review the efficacy and safety of PCBs for patients with ISR using comparisons with control groups. Electronic databases, such as MEDLINE, Embase and the Cochrane Central Register of Controlled Trials, were searched, and eligible studies that compared PCBs with uncoated balloons (UCBs) or drug-eluting stents (DESs) in patients with ISR were considered. Subgroup analyses were performed with different control groups. Nine studies (1,488 patients, 1,608 lesions) were included in the meta-analysis. Compared with patients who underwent UCB angioplasty, those who underwent PCB angioplasty exhibited a clear superiority in late lumen loss (LLL) [weighted mean difference (WMD), -0.46; 95% confidence interval (CI), (-0.59)-(-0.34); P<0.00001] and major adverse cardiac events (MACEs) [odds ratio (OR), 0.21; 95% CI, 0.13-0.33; P<0.00001]. The OR for myocardial infarction (MI) (OR, 0.46; 95% CI, 0.15-1.47; P=0.19) did not reach statistical significance. PCBs were associated with similar outcomes when compared with DESs with regard to LLL (WMD, -0.04; 95% CI, -0.18-0.10; P=0.57), MACEs (OR, 0.74; 95% CI, 0.36-1.53; P=0.42) and the ORs for all endpoints, including total mortality, target lesion revascularization, MI, stent thrombosis and binary restenosis, and no statistically significant differences were found. This meta-analysis showed that PCBs are associated with superior outcomes when compared with UCBs in the management of ISR, and are at least as efficacious and as well tolerated as DESs.

Clinical Coronary In-Stent Restenosis Follow-Up after Treatment and Analyses of Clinical Outcomes

BACKGROUND

Clinical in-stent restenosis (CISR) is the main limitation of coronary angioplasty with stent implantation.

OBJECTIVE

Describe the clinical and angiographic characteristics of CISR and the outcomes over a minimum follow-up of 12 months after its diagnosis and treatment.

METHODS

We analyzed in 110 consecutive patients with CISR the clinical presentation, angiographic characteristics, treatment and combined primary outcomes (cardiovascular death, nonfatal acute myocardial infarction [AMI]) and combined secondary (unstable angina with hospitalization, target vessel revascularization and target lesion revascularization) during a minimal follow-up of one year.

RESULTS

Mean age was 61 ± 11 years (68.2% males). Clinical presentations included acute coronary syndrome (ACS) in 62.7% and proliferative ISR in 34.5%. CISR was treated with implantation of drug-eluting stents (DES) in 36.4%, Bare Metal Stent (BMS) in 23.6%, myocardial revascularization surgery in 18.2%, balloon angioplasty in 15.5% and clinical treatment in 6.4%. During a median follow-up of 19.7 months, the primary outcome occurred in 18 patients, including 6 (5.5%) deaths and 13 (11.8%) AMI events. Twenty-four patients presented a secondary outcome. Predictors of the primary outcome were CISR with DES (HR = 4.36 [1.44-12.85]; p = 0.009) and clinical treatment for CISR (HR = 10.66 [2.53-44.87]; p = 0.001). Treatment of CISR with BMS (HR = 4.08 [1.75-9.48]; p = 0.001) and clinical therapy (HR = 6.29 [1.35-29.38]; p = 0.019) emerged as predictors of a secondary outcome.

CONCLUSION

Patients with CISR present in most cases with ACS and with a high frequency of adverse events during a medium-term follow-up.

Histopathological heterogeneity of in-stent restenosis in four coronary endarterectomy specimens

Here, we histopathologically compare four patients undergoing coronary artery bypass with coronary endarterectomy and onlay patch grafting for in-stent restenosis (ISR) after the implantation of a bare-metal stent (BMS), sirolimus-eluting stent (SES), or paclitaxel-eluting stent (PES) in an everolimus-eluting stent (EES). Heterogeneity of ISR was noted histopathologically. In ISR for BMS, restenosis is likely caused by so-called neoatherosclerosis that occurred which altered the healing process of BMS implantation. Two ISR cases for SES showed a histopathological heterogeneity: one showed nodular calcified thrombus around stent strut protruding into the lumen, and the other showed concentric neointima composed of CD68-positive foam cell proliferation. In the ISR lesion for PES in EES, infiltrations with foam cells macrophages, particularly numerous eosinophilic cell infiltrations, suggest a peristent strut hypersensitivity reaction. We found a remarkable histopathological heterogeneity of ISR. The study using coronary endarterectomy specimens can give us pivotal information about the histopathological heterogeneity of ISR.

Mechanisms of balloon angioplasty and repeat stenting in patients with drug-eluting in-stent restenosis

BACKGROUND

Mechanisms of lumen gain during reinterventions in patients with drug-eluting stent (DES) in-stent restenosis (ISR) remain unsettled.

METHODS

We sought to assess the mechanisms of acute lumen gain after balloon angioplasty (BA) and repeat drug-eluting stent (DES) implantation in patients with DES-ISR. Following a prospective protocol 29 consecutive patients with DES-ISR were sequentially treated with BA and new DES implantation under a multimodality intracoronary imaging assessment including intravascular ultrasound (IVUS) and optical coherence tomography (OCT). Imaging studies were systematically obtained, at baseline, after BA, and after DES. Results of interventions were compared using volumetric and morphometric (ISR pattern and injury score) analyses.

RESULTS

IVUS and OCT demonstrated that acute lumen gain after BA and DES equally results from a reduction in intra-stent neointimal volume and further DES expansion. As compared with BA, repeat DES implantation not only increased final lumen (baseline 39.6±18.5mm(3), post-BA 58.6±26.6mm(3), post-DES 84.2±30.8mm(3), all p<0.001) but also provided a smoother lumen (injury score 1.57±0.86 vs 0.22±0.26, p<0.001). At the 9th month of angiographic follow-up (86% patients) in-stent late loss was 0.44±0.5mm and 4 patients (16%) developed ISR. The ISR pattern on OCT was not associated with the injury score after interventions or late angiographic findings. Likewise, the injury score did not predict late angiographic outcome.

CONCLUSIONS

In patients with DES ISR, lumen gain equally results from a reduction in intra-stent neointimal volume and further DES expansion. As compared with BA, repeat DES implantation provides a larger and smoother coronary lumen.