Percutaneous coronary interventional strategies for treatment of in-stent restenosis: a network meta-analysis

Efficacy of drug-coated balloon angioplasty in early versus late occurring drug-eluting stent restenosis: A pooled analysis from the randomized ISAR DESIRE 3 and DESIRE 4 trials

BACKGROUND

Whether there exist differences concerning clinical outcomes between patients presenting with early versus late DES-ISR undergoing treatment with drug-coated balloons (DCB) remains a scientific knowledge gap.

METHODS

This is a pooled analysis including patients with DES-ISR assigned to treatment with DCB in the setting of the ISAR DESIRE 3 and 4 trials. Clinical outcomes were evaluated according to time of occurrence of ISR after DES implantation, in patients presenting with early (≤12 months) versus late DES-ISR (>12 months) undergoing treatment with DCB. The primary endpoint of this analysis was major adverse cardiac event (MACE), defined as the combined incidence of death, myocardial infarction and target lesion revascularization (TLR) at 12 months after DCB treatment. Secondary endpoints included the incidence of death, myocardial infarction, TLR and target lesion thrombosis at 12 months after DCB treatment.

RESULTS

This analysis included 352 patients, 199 patients presented with early-ISR, 153 patients with late-ISR. Concerning the primary endpoint, patients with early-DES-ISR as compared those with late-DES-ISR showed significant higher risk (25.9% vs. 17.0%; p = .04). In a multivariate analysis including diabetic status, clinical presentation, previous coronary bypass graft and diameter stenosis after DCB-treatment, the adjusted hazard ratio showed significant higher risk for MACE of early-DES-ISR as compared to late-DES-ISR (HR_adj = 1.8, [95% CI = 1.1-3.0], p = .02).

CONCLUSION

Clinical outcome at 12 months after treatment of DES-ISR with DCB, showed significant higher clinical event rates in patients presenting with early DES restenosis, as compared with patients presenting with late DES restenosis.

Impact of Optimized Procedure-Related Factors in Drug-Eluting Balloon Angioplasty for Treatment of In-Stent Restenosis

OBJECTIVES

The aim of this study was to investigate the impact of optimizing procedure-related factors during drug-eluting balloon (DEB) angioplasty on clinical outcomes of drug-eluting stent in-stent restenosis (ISR).

BACKGROUND

Although DEB angioplasty is recommended as a reasonable option for ISR, recurrent target lesion failure (TLF) still occurs in many patients after DEB angioplasty.

METHODS

Consecutive patients with drug-eluting stent ISR treated with DEB (SeQuent Please) were collected from 4 centers in Korea. The primary outcome was 2-year TLF. Procedure-related modifiable independent predictors for TLF and their best cutoff values were determined.

RESULTS

In a total of 256 patients (309 lesions), TLF occurred in 52 patients (20.3%). Modifiable independent predictors of TLF among procedure-related factors were residual diameter stenosis after lesion preparation (residual percentage diameter stenosis [%DS]), DEB-to-stent ratio (BSR), and DEB inflation time (T_inflation), whose best cutoff values were 20%, 0.91, and 60 s, respectively. TLF rates were significantly higher in groups with residual %DS ≥20% (34.7% vs. 12.5%; adjusted hazard ratio: 2.15; 95% confidence interval: 1.86 to 2.48; p < 0.001), BSR ≤0.91 (46.4% vs. 21.9%; adjusted hazard ratio: 2.02; 95% confidence interval: 1.75 to 2.34; p < 0.001), and T_inflation ≤60 s (26.2% vs. 14.0%; adjusted hazard ratio: 1.82; 95% confidence interval: 1.36 to 2.45; p < 0.001). When classifying ISR lesions by combination of procedure-related factors, TLF occurred in 8.3% in the fully optimized procedure group (residual %DS <20%, BSR >0.91, and T_inflation >60 s) and 66.7% in the nonoptimized group (residual %DS ≥20%, BSR ≤0.91, and T_inflation ≤60 s) (p < 0.001).

CONCLUSIONS

Residual %DS after lesion preparation, BSR, and T_inflation were the only modifiable procedure-related factors in DEB angioplasty. Fully optimized DEB angioplasty with optimal lesion preparation, prolonged inflation, and sufficient dilation may play an important role in reducing TLF after DEB angioplasty.

Drug-coated balloons for coronary artery disease: current concepts and controversies

Drug-coated balloons (DCBs) are a novel development for percutaneous coronary intervention. The first successful application was in-stent restenosis but in recent years, strong evidence has been released for its use in native small-vessels disease. Additional applications such as acute myocardial infarction, chronic total occlusion and bifurcation lesions are still under investigation. This article reviews the key studies evaluating the role of DCBs in several settings and reports on interesting cases where DCBs showed positive results for high-risk patients with neoplasm, as well as with high bleeding risk, planned surgery or renal injury. We also highlight a new biodegradable therapy for coronary bifurcation treatment, in which a bioresorbable vascular scaffold is implanted in the main branch, completed with a DCB angioplasty in the side branch when a treatment is deemed necessary.

Reduced histologic neo in-stent restenosis after use of a paclitaxel-coated cutting balloon in porcine coronary arteries

The incidence of in-stent restenosis (ISR) has declined dramatically, but once it develops, no current treatment option, such as drug-eluting stents, drug-coated balloons, or cutting balloons (CBs), prevents re-narrowing of the stented atherosclerotic artery. In this preclinical study, we aimed to improve the efficacy of ISR treatment by coating CBs with paclitaxel (paclitaxel-eluting cutting balloon; PECB) and to characterize the histological features of neo-ISRs that arise after ISR treatment. ISR was induced by bare metal stent (BMS) implantation in coronary arteries in pigs. After one month of follow-up, the BMS-induced ISR was treated with either CB or PECB. After another month, we performed quantitative coronary angiography, explanted the treated arteries and assessed histopathological and histomorphometric parameters. In addition, we compared the histological features of neo-ISRs with pre-treatment ISRs. Injury, inflammation, fibrin deposition, and endothelialization scores were similar between the CB and PECB groups at one month after ISR treatment. Neointimal area (0.87±0.61 vs. 1.95±1.14 mm², p=0.02), mean neointimal thickness (0.40±0.39 vs. 0.99±0.56 mm, p=0.01), and percent area stenosis (27.3±20.4 vs. 48.3±22.9%, p=0.04) were decreased in PECB-treated coronary arteries compared to CB-treated arteries, respectively. Density of cells (predominantly smooth muscle cells; SMCs) was increased in neo-ISRs (3.51±3.05×10³ vs. 6.35±2.57×10³ cells/mm², p<0.01), but significantly more CD68⁺ and CD20⁺ cells were found in the pre-treatment ISRs. In conclusion, PECB treatment of ISRs led to better results in terms of smaller neointimal area and %area stenosis of the neo-ISR. SMC density was increased in neo-ISRs in contrast with higher percentage of CD68⁺ and CD20⁺ cells in pre-treatment ISRs.

What are the Pathological Concerns and Limitations of Current Drug-coated Balloon Technology?

The use of endovascular therapy for peripheral artery disease and coronary artery disease has increased and spread worldwide and is considered as the foremost, guideline-based invasive treatment. Drug-coated balloons (DCBs) utilise anti-proliferative drugs similar to drug-eluting stents; however, the do not leave any permanent metallic scaffold. Excipients and drug formulations play a crucial role in innovative DCB technologies and allow for treatment of lesions where stents are not suitable. Although the significance of downstream embolic effects after DCB use remains uncertain, several preclinical studies suggest such side effects might pose safety concerns. Recently, a meta-analysis of randomised controlled trials of paclitaxel devices suggested an association between increased mortality and paclitaxel device use. Subsequently, unfavourable criticism of paclitaxel devices attracted much attention and gave rise to a discussion about the safety of such devices. In this review, we will focus on the novel DCB technologies from the standpoint of preclinical studies and clinical trials, as well as discuss current controversies regarding the increase in death rates from paclitaxel-coated DCBs versus control devices seen in a recent meta-analysis of randomised controlled clinical trials.

A Review on the Comparison of Different Treatments for Carotid In-Stent Restenosis

Different treatment options for carotid in-stent restenosis (ISR) have been reported with good outcome, including carotid endarterectomy (CEA), repeated carotid angioplasty stenting (CAS) and percutaneous transluminal angioplasty (PTA) with drug-coated balloons (DCBs). However, the optimal treatment option for ISR has not yet been determined. A systematic literature search was performed in the databases of Medline, Embase, Cochrane library, and unpublished data from clinicaltrials.gov from 1990 to March 1, 2019. Studies were enrolled if they reported treatment strategies for carotid ISR treatment and met the inclusion criteria. After study inclusions, data were extracted and summarized. Totally 25 cross-sectional studies were included, containing 5 comparative studies, 16 studies using repeated PTA, and 4 studies adopting CEA treatment. Our study summarized the current available data, showing that all the studies could effectively relieve the carotid ISR by significantly improving the angiographic stenosis and decreasing the peak systolic velocity values. Meanwhile, CEA treatment had the best long-term effects in relieving restenosis, while re-PTA with stenting/balloon angioplasty had a certain rate of restenosis, ranging from 33% to 83%. Furthermore, re-PTA/stenting and balloon angioplasty treatment had less complications compared with CEA. Also, we analyzed the risk factors that might affect the long-term prognosis of carotid ISR patients. The therapeutic measures for carotid ISR had their own features, with CEA had the highest efficacy while re-PTA/stenting and balloon angioplasty were with less complications. More large-scale comparative clinical studies are needed to further ascertain the best strategies.

Angiography and Optical Coherence Tomography Assessment of the Drug-Coated Balloon ESSENTIAL for the Treatment of In-Stent Restenosis

OBJECTIVES

This study sought to assess the efficacy of the drug-coated balloon (DCB) ESSENTIAL for the treatment of in-stent restenosis (ISR).

BACKGROUND

DCBs have proven a valid therapeutic option for the management of ISR in several clinical trials, yet no class effect can be claimed. Accordingly, every new DCB model has to be individually evaluated through clinical studies.

METHODS

This is a prospective, multicenter study including consecutive patients undergoing percutaneous coronary intervention for ISR with the ESSENTIAL DCB. A 6-month quantitative coronary angiography (QCA)/optical coherence tomography (OCT) follow-up was scheduled. The primary endpoint was OCT-derived in-segment maximal area stenosis. Secondary endpoints included QCA-derived in-segment late lumen loss (LLL) and target lesion failure (TLF) rates at 6, 12, and 24 months. TLF was defined as the composite of cardiac death, target vessel myocardial infarction, and target lesion revascularization.

RESULTS

A total of 31 patients were successfully treated with DCB, with 67% of ISR corresponding to drug-eluting stents (DES). At 6 months, 26 patients underwent the scheduled angiographic follow-up. The mean value for in-segment maximal area stenosis was 51.4 ± 13% and the median value was 53% (IQR 46.4-59.5). In the DES-ISR subgroup, these parameters were 52.6 ± 10% and 55.2% (IQR 49.3-58.5), respectively. In-segment LLL was 0.25 ± 0.43 mm with only 2 (7.7%) patients showing binary restenosis (>50%). The incidence of TLF was 10% at 6 months, 13.3% at 12 months, and 13.3% at 24 months.

CONCLUSIONS

In this study, the ESSENTIAL DCB showed sustained efficacy in the prevention of recurrent restenosis after treatment of ISR.

SUMMARY

We sought to assess the efficacy of the drug-coated balloon ESSENTIAL for the treatment of in-stent restenosis through a prospective, multicenter study including QCA and OCT assessment at 6-month follow-up. The primary endpoint was in-segment maximal area stenosis. Among the 31 patients successfully treated with the ESSENTIAL DCB, an angiographic follow-up was conducted in 26. Mean in-segment maximal area stenosis was 51.4 ± 13% and the median value was 53% (IQR 46.4-59.5). In the DES-ISR subgroup, corresponding values were 52.6 ± 10% and 55.2% (IQR 49.3-58.5), respectively. The observed in-segment LLL was 0.25 ± 0.43 mm and binary restenosis rate was 7.7%. TLF was 10% at 6 months and 13.3% at 12 and 24 months.

Clinical outcomes of rotational atherectomy in severely calcified in-stent restenosis: a single-center, retrospective study

Neointimal calcification after stent implantation has been reported as one of the forms of neoatherosclerosis. There are a few patients with in-stent restenosis (ISR) and an undilatable calcified neointima who require rotational atherectomy to achieve sufficient acute gain in lumen diameter. However, the clinical outcomes of rotational atherectomy for undilatable calcified ISR have not been fully elucidated. Therefore, we investigated the safety and efficacy of rotational atherectomy for treating calcified ISR. This retrospective study included 17 patients (20 lesions) who had undergone percutaneous coronary intervention including rotational atherectomy to treat ISR with severely calcified neointima. Kaplan-Meier analysis was used to analyze the data. The mean age of the enrolled patients was 67±18 years, and 71% were men. The patients had highly atherogenic characteristics: 65% had diabetes mellitus and 53% were receiving hemodialysis. Procedural success was obtained in 19 (95%) patients, and the acute gain in lumen diameter was acceptable (1.7±0.6 mm). However, during a median follow-up of 571 days, the incidences of major adverse cardiac and cerebrovascular events per patient and clinical-driven target lesion revascularizations per lesion were relatively high. There were no differences in clinical outcomes according to the baseline characteristics, type of restenotic stents, and therapeutic strategy. In conclusion, clinical outcomes of rotational atherectomy for severely calcified ISR were unfavorable despite a high success rate and acceptable acute gain in lumen diameter.

Effect of combination of non-slip element balloon and drug-coating balloon for in-stent restenosis lesions (ELEGANT study)

BACKGROUND

In-stent restenosis (ISR) remains a problematic issue of coronary intervention. The non-slip element balloon (NSE) is a balloon catheter with 3 longitudinal nylon elements which are attached proximally and distally to the balloon component. The expectation is that this design of balloon is able to achieve a larger lumen area due to the elements, as well as reducing balloon slippage. We investigated whether NSE pre-dilatation improves angiographic outcomes compared to a high pressure non-compliant balloon pre-dilatation, followed by a drug-coating balloon (DCB) for treatment of ISR lesions with optical coherence tomographic imaging (OCT).

METHODS

Patients were eligible for the study if one or more in-stent restenosis lesions were treated with a paclitaxel-coating balloon. Patients were randomized to NSE pre-dilatation (NSE group) or high pressure non-compliant balloon pre-dilatation (POBA group) in a 1:1 fashion in 17 hospitals. The primary endpoint was in-segment late loss [post minimal lumen diameter (MLD)-follow-up MLD] at 8 months.

RESULTS

One hundred and five patients were allocated to each group. Balloon slippage (7.9% versus 22.9%, p=0.002) and geographical miss (6.9% versus 21.9%, p=0.002) were observed less in the NSE group compared to the POBA group. Acute gain was significantly larger in the NSE group (1.17±0.42mm versus 1.06±0.35mm, p=0.04), but post minimum stent lumen area analyzed by OCT was similar between the two groups (3.85±1.67mm² versus 3.81±1.93mm², p=0.64). At 8 months, average lesion length was significantly shorter than the POBA group (5.78±3.26mm versus 6.97±4.59mm, p=0.04), but average in-segment late loss was similar between the two groups (0.28±0.45mm versus 0.27±0.38mm, p=0.75).

CONCLUSION

Eight-month angiographic outcomes were similar between NSE and non-compliant balloon pre-dilatation with DCB for treatment of ISR lesions. However, NSE pre-dilatation has advantages such as reduction of balloon slippage and geographical miss during the procedure.

Treatment of In-Stent Restenosis by Excimer Laser Coronary Atherectomy and Drug-Coated Balloon: Serial Assessment with Optical Coherence Tomography

Objectives

We aimed to compare the results of neointimal modification before drug-coated balloon (DCB) treatment with excimer laser coronary atherectomy (ELCA) plus scoring balloon predilation versus scoring balloon alone in patients presenting with in-stent restenosis (ISR).

Background

Treatment of ISR with ELCA typically results in superior acute gain by neointima debulking. However, the efficacy of combination therapy of ELCA and DCB remains unknown.

Methods

A total of 42 patients (44 ISR lesions) undergoing DCB treatment with ELCA plus scoring balloon (ELCA group, n = 18) or scoring balloon alone (non-ELCA group, n = 24) were evaluated via serial assessment by optical coherence tomography (OCT) performed before, after intervention, and at 6 months.

Results

Although there was significantly greater frequency of diffuse restenosis and percent diameter stenosis (%DS) after intervention in the ELCA group, comparable result was shown in %DS, late lumen loss, and binary angiographic restenosis at follow-up. On OCT analysis, a decreased tendency in the minimum lumen area and a significant decrease in the minimum stent area were observed in the ELCA group between 6-month follow-up and after intervention (-0.89 ± 1.36 mm² vs. -0.09 ± 1.25 mm², p = 0.05, -0.49 ± 1.48 mm² vs. 0.28 ± 0.78 mm², p = 0.03, respectively). The changes in the neointimal area were similar between the groups, and target lesion revascularization showed comparable rates at 1 year (11.1% vs. 11.4%, p = 0.85).

Conclusions

Despite greater %DS after intervention, ELCA before DCB had possible benefit for late angiographic and clinical outcome.

Do outcomes following intervention for drug-eluting stent restenosis depend on whether the restenosed stent was polymer-free or polymer-coated?

INTRODUCTION AND OBJECTIVES

Outcomes of patients undergoing percutaneous intervention for drug-eluting stent (DES) restenosis are poorer than those in patients with bare-metal stent restenosis. It is unknown if this is related to the presence of polymer coating. We sought to compare outcomes after interventions for in-stent restenosis (ISR) of polymer-free DES vs durable polymer DES.

METHODS

Patients enrolled in the ISAR-TEST 5 randomized trial who underwent repeat percutaneous intervention for ISR during follow-up were included. Angiographic outcomes at 6 to 8 months and clinical outcomes at 2 years were analyzed and compared between 2 groups according to whether the restenosed stent was a polymer-free or a durable polymer DES. Multivariate analysis was used to adjust for differences between groups.

RESULTS

A total of 326 patients with ISR were included: 220 with ISR in polymer-free DES and 106 with ISR in durable polymer DES. Angiographic follow-up was available for 83.4% of patients. No difference was observed in recurrent binary restenosis between the 2 groups (31.7% vs 27.0%; P=.38; P_adjusted=.29). At 2 years, the composite of death, myocardial infarction, or repeat target lesion revascularization were similar between the 2 groups (35.7% vs 34.0%; HR=1.04, 95%CI, 0.70-1.55; P=.83; P_adjusted=.79). The rate of repeat target lesion revascularization was also similar in the 2 groups (29.8% vs 31.5%; HR=0.91, 95%CI, 0.60-1.39; P=.68; P_adjusted=.62).

CONCLUSIONS

In patients undergoing reintervention for DES-ISR, we found no evidence of differences in outcomes according to whether the restenosed stent was a polymer-free or durable polymer DES.

Percutaneous coronary intervention: balloons, stents and scaffolds

In this review, major achievements in the field of percutaneous coronary interventions are delineated with particular focus on Germany's contribution. The review deals with important developments, including the first heart catheterization and coronary angiography, first coronary balloon angioplasty and refinement of the technique, coronary stenting and optimization of adjunctive antithrombotic treatment, drug-eluting stents and balloons, as well as bioresorbable polymeric and metallic drug-eluting scaffolds.

Exosomes of Endothelial Progenitor Cells Inhibit Neointima Formation After Carotid Artery Injury

BACKGROUND

Exosomes released from endothelial progenitor cells (EPCs) play a protective role in various disease models. Both endothelial cell (EC) damage and smooth muscle cell (SMC) proliferation are involved in the pathological process of restenosis after angioplasty and stenting. Few studies have focused on the therapeutic role of exosomes in EC damage and SMC proliferation. In this study, we sought to investigate the effect of exosomes released by human fetal aorta-derived EPCs on the rat carotid artery balloon injury model in vivo. We also sought to determine the effect of exosomes on both ECs and SMCs in vitro.

METHODS

Exosomes (Exo group) or saline (Con group) were injected in rat carotid balloon injury model animals. The rats were sacrificed after 2, 4, 14, and 28 d, and injured carotid specimens were collected for Evans blue staining, hematoxylin-eosin staining, and immunohistochemistry.

RESULTS

When the Con group and the Exo group were compared, the reendothelialized areas were not significantly different after 2 or 4 d, as shown by Evans blue staining. The hematoxylin-eosin results showed that the intimal to medial area ratio was slightly but not significantly higher in the Exo group after 2 and 4 d. The immunohistochemistry results showed that the proliferation of SMCs was slightly higher in the Exo group after 2 and 4 d, but the difference was not significant. The reendothelialization area of the Con group was significantly smaller than that of the Exo group at day 14. Both the intimal to medial area ratio and SMC proliferation in the Exo group were significantly smaller than those of the Con group at 14 or 28 d. In the in vitro study, exosome treatment significantly enhanced the proliferation and migration of both ECs and SMCs.

CONCLUSIONS

Exosomes derived from EPCs could inhibit neointimal hyperplasia after carotid artery injury in rats. The protective effect of exosomes may manifest through the promotion of EC repair rather than direct suppression of proliferation and migration of smooth muscles cells.

Planning a future randomized clinical trial based on a network of relevant past trials

Background

The important role of network meta-analysis of randomized clinical trials in health technology assessment and guideline development is increasingly recognized. This approach has the potential to obtain conclusive results earlier than with new standalone trials or conventional, pairwise meta-analyses.

Methods

Network meta-analyses can also be used to plan future trials. We introduce a four-step framework that aims to identify the optimal design for a new trial that will update the existing evidence while minimizing the required sample size. The new trial designed within this framework does not need to include all competing interventions and comparisons of interest and can contribute direct and indirect evidence to the updated network meta-analysis. We present the method by virtually planning a new trial to compare biologics in rheumatoid arthritis and a new trial to compare two drugs for relapsing-remitting multiple sclerosis.

Results

A trial design based on updating the evidence from a network meta-analysis of relevant previous trials may require a considerably smaller sample size to reach the same conclusion compared with a trial designed and analyzed in isolation. Challenges of the approach include the complexity of the methodology and the need for a coherent network meta-analysis of previous trials with little heterogeneity.

Conclusions

When used judiciously, conditional trial design could significantly reduce the required resources for a new study and prevent experimentation with an unnecessarily large number of participants.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2740-2) contains supplementary material, which is available to authorized users.

Major adverse cardiac events and drug-coated balloon size in coronary interventions

Objective

In-stent restenosis (ISR) is a feared complication after coronary stent implantation. Drug-coated balloon (DCB) is being promoted as a treatment option for ISR. However, the benefit-risk ratio of DCB length has not been investigated. Longer DCBs release more anti-proliferative drug to the vessel wall; however, they are associated with a higher lesion length and vessel injury. Hypothesis: DCB length is associated with clinical outcome.

Methods

We analyzed 286 consecutive Pantera Lux (Biotronik, active component Paclitaxel) DCB-treated patients between April 2009 and June 2012. Of them, 176 patients were treated using a 15-mm DCB and 109 were treated using a 20-mm DCB. Baseline characteristics and major adverse cardiac events (MACE; death, myocardial infarction, and target lesion revascularization) during initial hospital stay and a 2-year follow-up period were obtained.

Results

Patients characteristics such as cardiovascular risk factors, prior diseases, co-medication, clinical presentation, target vessel, and left ventricular function did not differ between the groups. MACE during hospital course was similar [1.7% vs. 2.8%, relative risk (RR) 1.6, 95% confidence interval (CI) 0.3-7.9, p=0.554]. Likewise, at 2-year follow-up, MACE did not differ between the groups (23.2% vs. 27.5%, RR 1.2, 95% CI 0.6-1.5, p=0.408).

Conclusion

DCB length was not associated with clinical outcome during a 2-year follow-up period.

Patient-specific 3D printing simulation to guide complex coronary intervention

The field of three-dimensional printing applied to patient-specific simulation is evolving as a tool to enhance intervention results. We report the first case of a fully simulated percutaneous coronary intervention in a three-dimensional patient-specific model to guide treatment. An 85-year-old female presented with symptomatic in-stent restenosis in the ostial circumflex and was scheduled for percutaneous coronary intervention. Considering the complexity of the anatomy, patient setting and intervention technique, we elected to replicate the coronary anatomy using a three-dimensional model. In this way, we simulated the intervention procedure beforehand in the catheterization laboratory using standard materials. The procedure was guided by optical coherence tomography, with pre-dilatation of the lesion, implantation of a single drug-eluting stent in the ostial circumflex and kissing balloon inflation to the left anterior descending artery and circumflex. Procedural steps were replicated in the real patient's treatment, with remarkable parallelism in angiographic outcome and luminal gain at intracoronary imaging. In this proof-of-concept report, we show that patient-specific simulation is feasible to guide the treatment strategy of complex coronary artery disease. It enables the surgical team to plan and practice the procedure beforehand, and possibly predict complications and gain confidence.

Endovascular stent-induced alterations in host artery mechanical environments and their roles in stent restenosis and late thrombosis

Cardiovascular stent restenosis remains a major challenge in interventional treatment of cardiovascular occlusive disease. Although the changes in arterial mechanical environment due to stent implantation are the main causes of the initiation of restenosis and thrombosis, the mechanisms that cause this initiation are still not fully understood. In this article, we reviewed the studies on the issue of stent-induced alterations in arterial mechanical environment and discussed their roles in stent restenosis and late thrombosis from three aspects: (i) the interaction of the stent with host blood vessel, involve the response of vascular wall, the mechanism of mechanical signal transmission, the process of re-endothelialization and late thrombosis; (ii) the changes of hemodynamics in the lumen of the vascular segment and (iii) the changes of mechanical microenvironment within the vascular segment wall due to stent implantation. This review has summarized and analyzed current work in order to better solve the two main problems after stent implantation, namely in stent restenosis and late thrombosis, meanwhile propose the deficiencies of current work for future reference.

Paclitaxel-coated balloon treatment for functionally nonsignificant residual coronary lesions after balloon angioplasty

There is limited data on the efficacy of paclitaxel-coated balloon (PCB) compared to stents for de novo coronary lesions. The purpose of this study was to compare the efficacy of PCB treatment with stent implantation for de novo coronary lesions after successful plain old balloon angioplasty (POBA) guided by fractional flow reserve (FFR). In 200 patients scheduled for elective percutaneous coronary intervention (PCI) for de novo lesions, FFR was measured after POBA (POBA-FFR). If POBA-FFR was ≥ 0.75, patients were treated with PCB (PCB group, n = 78) or stent (Stent group, n = 73). If POBA-FFR was < 0.75, stent was implanted as planned (Reference group, n = 42). The primary endpoint was late lumen loss at 9 months and the secondary endpoint was adverse cardiac events (cardiac death, myocardial infarction, target lesion thrombosis, or repeat revascularization) at 12 months follow-up. There was no between-group differences in the POBA-FFR (0.87 ± 0.05 in PCB, 0.89 ± 0.06 in stent, p = 0.101). At 9 months, late lumen loss was significantly lower in the PCB group compared to the Stent group (0.05 ± 0.33 vs. 0.59 ± 0.76 mm, p < 0.001). Adverse cardiac events were not different between the PCB, Stent and Reference groups (2.6, 5.5, and 9.5% respectively; p = 0.430 for PCB vs. Stent group; p = 0.229 for the reference vs. both other groups). PCB treatment guided by POBA-FFR showed excellent 9 months angiographic and functional results, as well as comparable 12 months clinical outcomes, compared with stent implantation for de novo coronary lesions.

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).

Emerging roles for RNA-binding proteins as effectors and regulators of cardiovascular disease

The cardiovascular system comprises multiple cell types that possess the capacity to modulate their phenotype in response to acute or chronic injury. Transcriptional and post-transcriptional mechanisms play a key role in the regulation of remodelling and regenerative responses to damaged cardiovascular tissues. Simultaneously, insufficient regulation of cellular phenotype is tightly coupled with the persistence and exacerbation of cardiovascular disease. Recently, RNA-binding proteins such as Quaking, HuR, Muscleblind, and SRSF1 have emerged as pivotal regulators of these functional adaptations in the cardiovascular system by guiding a wide-ranging number of post-transcriptional events that dramatically impact RNA fate, including alternative splicing, stability, localization and translation. Moreover, homozygous disruption of RNA-binding protein genes is commonly associated with cardiac- and/or vascular complications. Here, we summarize the current knowledge on the versatile role of RNA-binding proteins in regulating the transcriptome during phenotype switching in cardiovascular health and disease. We also detail existing and potential DNA- and RNA-based therapeutic approaches that could impact the treatment of cardiovascular disease in the future.

Association of serum procalcitonin level with in-stent restenosis in patients undergoing bare-metal stent implantation

AIM

Procalcitonin (PCT) is an inflammatory marker and elevated PCT levels are associated with cardiovascular events. We assessed whether PCT level is an independent predictor of bare-metal stent (BMS) in-stent restenosis (ISR).

PATIENTS & METHODS

We evaluated 240 patients undergoing BMS implantation. Serum PCT levels were measured before procedure. Patients were classified as ISR(-) group (n = 120) and ISR(+) group (n = 120).

RESULTS

Serum PCT levels were higher in the ISR (+) group (p < 0.001). At multivariate analysis, PCT (odds ratio [OR] 1.561; p = 0.012), stent length (OR: 1.089), stent diameter (OR: 0.141) and uric acid (OR: 1.465) were independent predictors of ISR.

CONCLUSION

Serum PCT is independently associated with ISR and increased PCT levels may provide useful information for the risk of BMS-ISR.

Comparison of drug-eluting stents and drug-coated balloon for the treatment of drug-eluting coronary stent restenosis: A randomized RESTORE trial

BACKGROUND

This study sought to evaluate the optimal treatment for in-stent restenosis (ISR) of drug-eluting stents (DESs).

METHODS

This is a prospective, multicenter, open-label, randomized study comparing the use of drug-eluting balloon (DEB) versus second-generation everolimus-eluting stent for the treatment of DES ISR. The primary end point was in-segment late loss at 9-month routine angiographic follow-up.

RESULTS

A total of 172 patients were enrolled, and 74 (43.0%) patients underwent the angiographic follow-up. The primary end point was not different between the 2 treatment groups (DEB group 0.15±0.49 mm vs DES group 0.19±0.41 mm, P=.54). The secondary end points of in-segment minimal luminal diameter (MLD) (1.80±0.69 mm vs 2.09±0.46 mm, P=.03), in-stent MLD (1.90±0.71 mm vs 2.29±0.48 mm, P=.005), in-segment percent diameter stenosis (34%±21% vs 26%±15%, P=.05), and in-stent percent diameter stenosis (33%±21% vs 21%±15%, P=.002) were more favorable in the DES group. The composite of death, myocardial infarction, or target lesion revascularization at 1 year was comparable between the 2 groups (DEB group 7.0% vs DES group 4.7%, P=.51).

CONCLUSIONS

Treatment of DES ISR using DEB or second-generation DES did not differ in terms of late loss at 9-month angiographic follow-up, whereas DES showed better angiographic results regarding minimal MLD and percent diameter stenosis. Both treatment strategies were safe and effective up to 1year after the procedure.

Angiographic and clinical outcomes of patients treated with drug-coated balloon angioplasty for in-stent restenosis after coronary bifurcation stenting with a two-stent technique

AIMS

We conducted this study to evaluate the efficacy of drug-coated balloon therapy for in-stent restenosis after coronary bifurcation stenting.

METHODS AND RESULTS

Patients who underwent angioplasty with at least one paclitaxel-coated balloon for in-stent restenosis after bifurcation intervention using a two-stent approach were included. Two types of paclitaxel-coated balloon were used, with either an iopromide (iopromide-PCB) or a butyryl tri-n-hexyl citrate (BTHC-PCB) excipient. Angiographic surveillance was planned at six to eight months. Quantitative coronary angiography analysis was carried out with dedicated bifurcation analysis software. Clinical follow-up was performed to one year. In total, 177 patients were included in this study. Information on the type of stent technique used at the time of the index intervention was available for 145 (81.9%) patients: the culotte technique was used in 123 (69.5%) and T-stenting in 22 (12.4%) patients. Iopromide-PCB and BTHC-PCB were used in 124 (70%) and 53 (30%) patients, respectively. Of 125 patients who underwent angiographic follow-up, 30 cases (24%) of binary restenosis were observed. At one year, the composite endpoint of death, myocardial infarction or target lesion revascularisation was observed in 35 patients (24%). There was no significant difference in the incidence of angiographic and clinical outcomes between iopromide-PCB versus BTHC-PCB.

CONCLUSIONS

In the setting of in-stent restenosis after coronary bifurcation stenting, drug-coated balloons demonstrated good clinical efficacy without the requirement for further stent implantation. There were similar outcomes between iopromide-PCB and BTHC-PCB.

Comparison of new-generation drug-eluting stents versus drug-coated balloon for in-stent restenosis: a meta-analysis of randomised controlled trials

OBJECTIVE

The study sought to compare angiographic and clinical outcomes of new-generation drug-eluting stents (DES) versus drug-coated balloon (DCB) in patients with coronary in-stent restenosis (ISR).

DESIGN

Meta-analysis using data from randomised trial found by searches on PubMed, the Cochrane Library, ClinicalTrials.gov and websites of major cardiovascular congresses.

SETTING

Only randomised trials comparing DES with DCB were included.

PARTICIPANTS

Patients with ISR in the included trials.

INTERVENTIONS

New-generation DES versus DCB.

OUTCOMES

The angiographic and clinical outcomes including cardiac death, all-cause death, myocardial infarction, target lesion revascularisation (TLR), target vessel revascularisation (TVR), major adverse cardiac events (MACE) and stent thrombosis were investigated.

RESULTS

Five trials including 913 patients were eligible and included. Pooled analysis in angiographic results identified that new-generation DES were associated with higher acute luminal gain (-0.31 mm, 95% CI -0.42 to -0.20, P<0.001) and lower per cent diameter stenosis (risk ratio (RR): 0.28, 95% CI 0.02 to 0.55, P=0.04). DES significantly reduced the risk of TLR (RR: 1.96, 95% CI 1.17 to 3.28, P=0.01) compared with DCB; however, there was no statistical differences for MACE (RR: 1.21, 95% CI 0.67 to 2.17, P=0.53), myocardial infarction (RR: 1.16, 95% CI 0.55 to 2.48, P=0.69) and cardiac death (RR: 1.80, 95% CI 0.60 to 5.39, P=0.29).

CONCLUSIONS

Interventions with new-generation DES appear to be associated with significant reduction in per cent diameter stenosis and TLR at short-term follow-up, but had similar MACE, myocardial infarction and cardiac death for patients with coronary ISR compared with DCB. Appropriately powered studies with longer term follow-up are warranted to confirm these findings.

Outcomes of non-invasive diagnostic modalities for the detection of coronary artery disease: network meta-analysis of diagnostic randomised controlled trials

OBJECTIVE

To evaluate differences in downstream testing, coronary revascularisation, and clinical outcomes following non-invasive diagnostic modalities used to detect coronary artery disease.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

Medline, Medline in process, Embase, Cochrane Library for clinical trials, PubMed, Web of Science, SCOPUS, WHO International Clinical Trials Registry Platform, and Clinicaltrials.gov.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Diagnostic randomised controlled trials comparing non-invasive diagnostic modalities in patients presenting with symptoms suggestive of low risk acute coronary syndrome or stable coronary artery disease.

DATA SYNTHESIS

A random effects network meta-analysis synthesised available evidence from trials evaluating the effect of non-invasive diagnostic modalities on downstream testing and patient oriented outcomes in patients with suspected coronary artery disease. Modalities included exercise electrocardiograms, stress echocardiography, single photon emission computed tomography-myocardial perfusion imaging, real time myocardial contrast echocardiography, coronary computed tomographic angiography, and cardiovascular magnetic resonance. Unpublished outcome data were obtained from 11 trials.

RESULTS

18 trials of patients with low risk acute coronary syndrome (n=11 329) and 12 trials of those with suspected stable coronary artery disease (n=22 062) were included. Among patients with low risk acute coronary syndrome, stress echocardiography, cardiovascular magnetic resonance, and exercise electrocardiograms resulted in fewer invasive referrals for coronary angiography than coronary computed tomographic angiography (odds ratio 0.28 (95% confidence interval 0.14 to 0.57), 0.32 (0.15 to 0.71), and 0.53 (0.28 to 1.00), respectively). There was no effect on the subsequent risk of myocardial infarction, but estimates were imprecise. Heterogeneity and inconsistency were low. In patients with suspected stable coronary artery disease, an initial diagnostic strategy of stress echocardiography or single photon emission computed tomography-myocardial perfusion imaging resulted in fewer downstream tests than coronary computed tomographic angiography (0.24 (0.08 to 0.74) and 0.57 (0.37 to 0.87), respectively). However, exercise electrocardiograms yielded the highest downstream testing rate. Estimates for death and myocardial infarction were imprecise without clear discrimination between strategies.

CONCLUSIONS

For patients with low risk acute coronary syndrome, an initial diagnostic strategy of stress echocardiography or cardiovascular magnetic resonance is associated with fewer referrals for invasive coronary angiography and revascularisation procedures than non-invasive anatomical testing, without apparent impact on the future risk of myocardial infarction. For suspected stable coronary artery disease, there was no clear discrimination between diagnostic strategies regarding the subsequent need for invasive coronary angiography, and differences in the risk of myocardial infarction cannot be ruled out.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registry no CRD42016049442.