A randomized comparison of a sirolimus-eluting stent with a standard stent for coronary revascularization

RhoA inhibitor-eluting stent attenuates restenosis by inhibiting YAP signaling

OBJECTIVE

Current drug-eluting stent (DES) treatment is promising, but it still has the drawback of in-stent restenosis, which remains a clinically relevant problem. Efforts should be made to discover new signaling molecules and novel potential targets for the prevention of arterial restenosis. In this study, we fabricated a novel DES targeting the RhoA pathway and further examined this promising strategy in vitro and in a rabbit carotid model.

METHODS

Active RhoA expression is correlated with the synthetic smooth muscle phenotype, and the RhoA inhibitor rhosin suppresses this phenotypic modulation at both transcriptional and translational levels. We further demonstrated that the RhoA inhibitor rhosin might act through the YAP pathway in smooth muscle cell phenotype modulation by a gain-of-function assay. Moreover, we fabricated a RhoA inhibitor-eluting stent and tested it in a rabbit carotid model.

RESULTS

Compared with a bare-metal stent, the RhoA inhibitor-eluting stent significantly attenuated neointimal formation at 6 months. However, overexpression of YAP by lentivirus blocked the antirestenosis effect of the RhoA inhibitor-eluting stent and repressed smooth muscle-specific genes.

CONCLUSIONS

RhoA inhibitor-eluting stents attenuate neointimal formation through inhibition of the YAP signaling pathway. This novel DES may represent a potential strategy for the treatment of in-stent restenosis.

Transcatheter ductus arteriosus stenting in paediatric cardiology: Indications, results and perspectives

Stenting the arterial duct emerged in the early 1990s as an alternative to a variety of surgical interventions in neonates with a duct-dependent pulmonary or systemic circulation complex defect. Furthermore, palliative ductal stenting has been applied in older children with severe suprasystemic pulmonary arterial hypertension, as an alternative to surgical shunts, such as Potts anastomosis. Early results of this technique were discouraging, but by learning from the failures of the past, ductal stenting has become a reliable palliative therapy. In this review, we aim to describe the historical evolution of ductal stenting, its different clinical applications and outcomes, and future perspectives for this strategy in congenital cardiac catheterization.

Ending Restenosis: Inhibition of Vascular Smooth Muscle Cell Proliferation by cAMP

Increased vascular smooth muscle cell (VSMC) proliferation contributes towards restenosis after angioplasty, vein graft intimal thickening and atherogenesis. The second messenger 3′ 5′ cyclic adenosine monophosphate (cAMP) plays an important role in maintaining VSMC quiescence in healthy vessels and repressing VSMC proliferation during resolution of vascular injury. Although the anti-mitogenic properties of cAMP in VSMC have been recognised for many years, it is only recently that we gained a detailed understanding of the underlying signalling mechanisms. Stimuli that elevate cAMP in VSMC inhibit G₁-S phase cell cycle progression by inhibiting expression of cyclins and preventing S-Phase Kinase Associated Protein-2 (Skp2-mediated degradation of cyclin-dependent kinase inhibitors. Early studies implicated inhibition of MAPK signalling, although this does not fully explain the anti-mitogenic effects of cAMP. The cAMP effectors, Protein Kinase A (PKA) and Exchange Protein Activated by cAMP (EPAC) act together to inhibit VSMC proliferation by inducing Cyclic-AMP Response Element Binding protein (CREB) activity and inhibiting members of the RhoGTPases, which results in remodelling of the actin cytoskeleton. Cyclic-AMP induced actin remodelling controls proliferation by modulating the activity of Serum Response Factor (SRF) and TEA Domain Transcription Factors (TEAD), which regulate expression of genes required for proliferation. Here we review recent research characterising these mechanisms, highlighting novel drug targets that may allow the anti-mitogenic properties of cAMP to be harnessed therapeutically to limit restenosis.

Drug-Eluting Stents Versus Bare-Metal Stents in Saphenous Vein Graft Intervention

Background Percutaneous coronary intervention with drug-eluting stents (DES) has been increasingly used for revascularization of saphenous vein graft stenosis without strong clinical evidence favoring their use. Randomized controlled trials comparing DES versus bare-metal stents (BMS) in saphenous vein graft-percutaneous coronary intervention have been inconclusive. Methods and Results We performed a comprehensive literature search through May 15, 2018, for all eligible studies comparing DES versus BMS in patients with saphenous vein graft stenosis in PubMed, EMBASE, SCOPUS, Google Scholar, and ClinicalTrials.gov. Clinical outcomes included all-cause mortality, cardiovascular mortality, major adverse cardiovascular events, myocardial infarction, stent thrombosis, and target vessel revascularization. Six randomized controlled trials were eligible and included 1582 patients, of whom 797 received DES and 785 received BMS. The follow-up period ranged from 18 months to 60 months. There was no statistically significant difference between DES and BMS for all-cause mortality (risk ratio [RR],1.11; 95% CI, 0.0.77-1.62; P=0.57), cardiovascular mortality (RR, 1.00; 95% CI, 0.64-1.57; P=0.99), major adverse cardiovascular events (RR, 0.83; 95% CI, 0.63-1.10; P=20), target vessel revascularization (RR, 0.73; 95% CI, 0.48-1.11; P=0.14), myocardial infarction (RR, 0.74; 95% CI, 0.48-1.16; P=0.19), or stent thrombosis (RR, 1.06; 95% CI, 0.42-2.65; P=0.90). Conclusions In patients undergoing percutaneous coronary intervention for saphenous vein graft lesions, our results showed that there was no significant difference between DES and BMS for mortality, major adverse cardiovascular events, target vessel revascularization, myocardial infarction, or stent thrombosis.

Experimentally validated simulation of coronary stents considering different dogboning ratios and asymmetric stent positioning

In-stent restenosis remains a major problem of arteriosclerosis treatment by stenting. Expansion-optimized stents could reduce this problem. With numerical simulations, stent designs/ expansion behaviours can be effectively analyzed. For reasons of efficiency, simplified models of balloon-expandable stents are often used, but their accuracy must be challenged due to insufficient experimental validation. In this work, a realistic stent life-cycle simulation has been performed including balloon folding, stent crimping and free expansion of the balloon-stent-system. The successful simulation and validation of two stent designs with homogenous and heterogeneous stent stiffness and an asymmetrically positioned stent on the balloon catheter confirm the universal applicability of the simulation approach. Dogboning ratio, as well as the final dimensions of the folded balloon, the crimped and expanded stent, correspond well to the experimental dimensions with only slight deviations. In contrast to the detailed stent life-cycle simulation, a displacement-controlled simulation can not predict the transient stent expansion, but is suitable to reproduce the final expanded stent shape and the associated stress states. The detailed stent life-cycle simulation is thus essential for stent expansion analysis/optimization, whereas for reasons of computational efficiency, the displacement-controlled approach can be considered in the context of pure stress analysis.

Real-World Use Of Ultrathin-Strut Biodegradable Polymer-Coated Sirolimus-Eluting Stents In Patients With Coronary Artery Disease: 6-Month Clinical Outcomes

BACKGROUND

Although a number of drug-eluting stents have been developed with different design, composition, and polymers, the search for an ideal drug-eluting stent is ongoing. The Tetriflex (Sahajanand Medical Technology, Surat, India) is a newer-generation, ultrathin (60 µm) biodegradable polymer-coated sirolimus-eluting stent (SES) designed with a unique long dual Z-link on a cobalt-chromium alloy. The present registry aimed to evaluate the safety and clinical outcomes of the Tetriflex SES at 6-month post-implantation.

METHODS

This was an investigator-initiated, retrospective, multicenter, single-arm, observational registry conducted at five tertiary-care centers in India. A total of 1,269 consecutive patients with coronary artery disease who underwent implantation of at least one Tetriflex SES between March 2017 and March 2018 were included. The primary outcome was considered a composite of cardiac death, myocardial infarction and target-lesion revascularization (TLR) at 6-month follow-up. Stent thrombosis was evaluated as a safety outcome at 6-month follow-up.

RESULTS

The mean age of patients was 54.99±10.80 years. Among 1,515 lesions treated with 1,682 Tetriflex SES, 58.3% were type C lesions. Six-month follow-up was done for 1,245 of 1,269 (98.1%) patients. At 6 months, composite events had occurred in 31 (2.5%) patients, consisting of ten (0.8%) cardiac deaths, 16 (1.3%) myocardial infarctions, and five (0.4%) TLRs. Stent thrombosis was observed in seven (0.56%) cases at 6 months. A subgroup analysis between diabetic and nondiabetic patients did not reveal any statistically significant difference for clinical outcomes at 6-month follow-up.

CONCLUSION

The results of the current registry outline the safety and effectiveness of the Tetriflex SES in real-world patients, as it displayed favorable clinical outcomes at 6-month follow-up, with low incidence of TLR and stent thrombosis.

Long-term clinical outcomes after treatment of stent restenosis with two drug-coated balloons

BACKGROUND

Treatment of in-stent restenosis (ISR) is still a clinical challenge in interventional cardiology. Paclitaxel-coated balloons (PCBs) are an attractive therapeutic option for ISR. There are several different types of PCBs available for percutaneous coronary intervention, but to date, comparative data between different types of PCBs for the treatment of ISR are scarce.

PATIENTS AND METHODS

This single centre, nonrandomized, retrospective study under real-world condition included 194 patients with 194 ISR treated by repeat percutaneous coronary intervention with PCBs. The primary end point was major adverse cardiac events (MACEs), defined as cardiac death, myocardial infarction and need for target lesion revascularization (TLR) at 1 year. Secondary end points were MACE and TLR at long-term follow-up.

RESULTS

Baseline clinical and angiographic parameters were comparable between the two groups. Patients in the iopromide-based PCB and butyryl-tri-hexyl citrate (BTHC)-PCB groups were followed up for 32.2±20.5 and 24.2±13.3 months, respectively (P=0.001). MACEs at 1-year follow-up were 15.0 and 15.8% (P=0.879) for the BTHC-PCB and iopromide-based PCB groups, respectively. TLR, myocardial infarction and cardiac death for BTHC-PCB versus iopromide-based PCB at 1-year follow-up were 9.6 versus 11.8%, P=0.622; 5.3 versus 3.9%, P=0.640; and 5.3 versus 3.9%, P=0.640, respectively. If complete follow-up periods were included in the analysis, BTHC-PCB and iopromide-based PCB had comparable rates of MACE (P=0.835) and TLR (P=0.792).

CONCLUSION

BTHC-PCB and iopromide-based PCB had comparable rates of MACE and TLR for the treatment of ISR at 1-year and long-term follow-up.

Identification and Analysis of Differentially Expressed Genes in Human Saphenous Vein Endothelial Cells Overexpressing Domain-Containing mTOR-Interacting Protein (DEPTOR) by RNA-Seq

Background

Autologous saphenous vein is the most common choice for coronary artery bypass grafting. This study was conducted to identify and characterize differentially expressed genes (DEGs) induced by overexpressing DEPTOR in human saphenous vein endothelial cells (hsVECs) that might play roles in restenosis.

Material/Methods

hsVECs isolated from the saphenous veins were transfected with DEPTOR overexpression vector and analyzed for mTOR expression. RNA was prepared from the cells and sequenced using high-throughput sequencing technology (RNA-Seq). The DEGs were analyzed based on enrichment scores in GO terms and KEGG pathways.

Results

The cells had typical hsVEC morphology and characteristics based on the HE staining and immunohistochemical and immunofluorescence assays. The expression of mTOR increased, and 102 genes were upregulated, and 409 genes were downregulated after DEPTOR overexpression. KEGG analysis showed that the DEGs were mainly enriched in 20 signal pathways, such as Focal adhesion and ECM-receptor interaction pathways. The DEGs were enriched in GO terms such as integrin binding and glycosaminoglycan binding. For cellular components, GO analysis revealed that the DEGs were enriched in main axon, plasma membrane part, cell junction, and proteinaceous extracellular matrix. DEGs included many cytokines, such as bone morphogenetic protein-7, interleukin-8, interleukin-1β, and inhibin, which have important effects on vascular growth and inflammation.

Conclusions

The overexpression of DEPTOR in hsVECs results in DEGs that are involved in cell proliferation and differentiation, intercellular junction, and extracellular matrix receptor. These findings may provide valuable molecular information for improving venous permeability through manipulation of DEPTOR and related mTOR pathways.

The Smoker's Paradox Revisited: A Patient-Level Pooled Analysis of 18 Randomized Controlled Trials

OBJECTIVES

This study examined the smoker's paradox using patient-level data from 18 prospective, randomized trials of patients undergoing percutaneous coronary intervention (PCI) with stent implantation.

BACKGROUND

Studies on the effects of smoking and outcomes among patients undergoing PCI have reported conflicting results.

METHODS

Data from the RAVEL, E-SIRIUS, SIRIUS, C-SIRIUS, TAXUS IV and V, ENDEAVOR II to IV, SPIRIT II to IV, HORIZONS-AMI, COMPARE I and II, PLATINUM, and TWENTE I and II randomized trials were pooled. Patients were stratified by smoking status at time of enrollment. The 1- and 5-year ischemic outcomes were compared.

RESULTS

Among 24,354 patients with available data on smoking status, 6,722 (27.6%) were current smokers. Smokers were younger and less likely to have diabetes mellitus; hypertension; hyperlipidemia; or prior myocardial infarction (MI), PCI, or coronary artery bypass grafting. Angiographically, smokers had longer lesions, more complex lesions, and more occlusions, but were less likely to have moderate or severe calcification or tortuosity. At 5 years, smokers had significantly higher rates of MI (7.8% vs. 5.6%; p < 0.0001) and definite or probable stent thrombosis (3.5% vs. 1.8%; p < 0.0001); however, there were no differences in the rates of death, cardiac death, target lesion revascularization, or composite endpoints (cardiac death, target vessel MI, or ischemic target lesion revascularization). After multivariable adjustment for potential confounders, smoking was a strong independent predictor of death (hazard ratio [HR]: 1.86; 95% confidence interval [CI]: 1.63 to 2.12; p < 0.0001), cardiac death (HR: 1.68; 95% CI: 1.38 to 2.05; p < 0.0001), MI (HR: 1.38; 95% CI: 1.20 to 1.58; p < 0.0001), stent thrombosis (HR: 1.60; 95% CI: 1.28 to 1.99; p < 0.0001), and target lesion failure (HR: 1.17; 95% CI: 1.05 to 1.30; p = 0.005).

CONCLUSIONS

The present large, patient-level, pooled analysis with 5-year follow-up clearly demonstrates smoking to be an important predictor of adverse outcomes after PCI.

Angiographic and Clinical Outcomes After Stent-less Coronary Intervention Using Rotational Atherectomy and Drug-Coated Balloon in Patients with De Novo Lesions

OBJECTIVES

We investigated angiographic and clinical outcomes in patients with de novo lesions undergoing rotational atherectomy (RA) followed by drug-coated balloon (DCB) dilation (RA/DCB).

BACKGROUND

Implantation of drug-eluting stent (DES) has been a mainstay of the interventional treatment of coronary artery disease (CAD); however, there still remain several DES-unsuitable clinical/lesion conditions. Nowadays DCB for de novo lesions has attracted more attention, and RA, which tends not to cause major dissection but to debulk intima, might be one of suitable pre-treatments before DCB.

METHODS AND RESULTS

Thirty patients (34 lesions) undergoing RA/DCB for de novo lesions were enrolled. Clinical/lesion background included severe calcification, calcified nodule, inlet/outlet of aneurysm, ostial lesion, severe thrombocytopenia, bleeding tendency, and/or sequelae of Kawasaki disease. The largest burr size used was 1.83 ± 0.23 mm, and the mean DCB diameter was 2.71 ± 0.47 mm. Angiographic success was obtained in 94% of the lesions. No acute closure but 1 no reflow occurred. Repeat angiography (mean, 6.6 months after procedure) was performed for 19 lesions. Frequency of binary restenosis was 21.1%, and late lumen loss was 0.34 ± 0.30 mm. During a mean follow-up period of 13.1 months, 6 deaths (2 sudden deaths, 1 cardiac death, 3 non-cardiac deaths), 2 strokes, and 2 target lesion revascularizations were observed.

CONCLUSIONS

Stent-less PCI using RA/DCB might be an alternative revascularization therapy for CAD patients complicated with DES-unsuitable conditions.

Multi-objective optimisation of material properties and strut geometry for poly(L-lactic acid) coronary stents using response surface methodology

Coronary stents for treating atherosclerosis are traditionally manufactured from metallic alloys. However, metal stents permanently reside in the body and may trigger undesirable immunological responses. Bioresorbable polymer stents can provide a temporary scaffold that resorbs once the artery heals but are mechanically inferior, requiring thicker struts for equivalent radial support, which may increase thrombosis risk. This study addresses the challenge of designing mechanically effective but sufficiently thin poly(L-lactic acid) stents through a computational approach that optimises material properties and stent geometry. Forty parametric stent designs were generated: cross-sectional area (post-dilation), foreshortening, stent-to-artery ratio and radial collapse pressure were evaluated computationally using finite element analysis. Response surface methodology was used to identify performance trade-offs by formulating relationships between design parameters and response variables. Multi-objective optimisation was used to identify suitable stent designs from approximated Pareto fronts and an optimal design is proposed that offers comparable performance to designs in clinical practice. In summary, a computational framework has been developed that has potential application in the design of high stiffness, thin strut polymeric stents.

Microporous methacrylated glycol chitosan-montmorillonite nanocomposite hydrogel for bone tissue engineering

Injectable hydrogels can fill irregular defects and promote in situ tissue regrowth and regeneration. The ability of directing stem cell differentiation in a three-dimensional microenvironment for bone regeneration remains a challenge. In this study, we successfully nanoengineer an interconnected microporous networked photocrosslinkable chitosan in situ-forming hydrogel by introducing two-dimensional nanoclay particles with intercalation chemistry. The presence of the nanosilicates increases the Young’s modulus and stalls the degradation rate of the resulting hydrogels. We demonstrate that the reinforced hydrogels promote the proliferation as well as the attachment and induced the differentiation of encapsulated mesenchymal stem cells in vitro. Furthermore, we explore the effects of nanoengineered hydrogels in vivo with the critical-sized mouse calvarial defect model. Our results confirm that chitosan-montmorillonite hydrogels are able to recruit native cells and promote calvarial healing without delivery of additional therapeutic agents or stem cells, indicating their tissue engineering potential.

Injectable hydrogels could be used to repair bone defects. Here the authors incorporate nanoclay particles into chitosan creating an interconnected microporous hydrogel and show that this hydrogel can support MSC proliferation and differentiation in vitro, and support the recruitment of native cells and bone regeneration in a mouse calvarial defect model.

Impact of lesion angle on optical coherence tomography findings and clinical outcomes after drug-eluting stent implantation in curved vessels

Tortuous coronary lesions are associated with adverse outcomes after implantation of bare metal or first-generation drug-eluting stents (DESs). We investigated the impact of lesion angle on vessel wall injuries and stent apposition as assessed by optical coherence tomography (OCT) after second- and newer-generation DES implantation. We investigated 95 de novo lesions treated with a single DES (62 platinum-chromium everolimus-eluting stents and 33 bioresorbable-polymer sirolimus-eluting stents). Post-intervention OCT findings were compared between angled lesions (≥ 45°; n = 33) and non-angled lesions (< 45°; n = 62). The 12-month clinical outcomes were also compared between the groups. Cross-sectional OCT analysis revealed that compared to non-angled lesions, angled ones had a significantly higher incidence of intra-stent dissection around the centre of the angle (19.7% vs. 10.8%, p = 0.01) and incomplete stent apposition (ISA) in the distal and proximal sub-segments (10.0% vs. 4.1%, p = 0.002; 15.3% vs. 7.9%, p < 0.001, respectively). Strut-based analysis also showed that angled lesions demonstrated a higher rate of malapposed strut in the distal and proximal sub-segments (3.0% vs. 0.9%, p < 0.001; 4.3% vs. 1.8%, p < 0.001, respectively). The 12 month clinical outcomes were comparable between the groups. Compared to non-angled lesions, angled coronary lesions were associated with a higher incidence of intra-stent dissection and ISA on post-intervention OCT after implantation of second- and newer-generation DESs.

High-Density Lipoproteins and Apolipoprotein A-I Improve Stent Biocompatibility

Revascularization because of coronary artery disease is commonly achieved by percutaneous coronary intervention with stent deployment. Refinement in interventional techniques, major improvements in stent design (particularly drug-eluting stents), and adjunctive pharmacotherapy with dual antiplatelet regimens have led to marked reductions in the overall rates of stent failure. However, even with the advancements made in the latest generation of drug-eluting stents, unresolved biological problems persist including delayed re-endothelialization and neoatherosclerosis, which can promote late expansion of the neointima and late stent thrombosis. Novel strategies are still needed beyond what is currently available to specifically address the pathobiological processes that underpin the residual risk for adverse clinical events. This review focuses on the emerging evidence that HDL (high-density lipoproteins) and its main apo (apolipoprotein), apoA-I, exhibit multiple vascular biological functions that are associated with an improvement in stent biocompatibility. HDL/apoA-I have recently been shown to inhibit in-stent restenosis in animal models of stenting and suppress smooth muscle cell proliferation in in vitro studies. Reconstituted HDL also promotes endothelial cell migration, endothelial progenitor cell mobilization, and re-endothelialization. Furthermore, reconstituted HDL decreases platelet activation and HDL cholesterol is inversely associated with the risk of thrombosis. Finally, reconstituted HDL/apoA-I suppresses key inflammatory mechanisms that initiate in-stent neoatherosclerosis and can efflux cholesterol from plaque macrophages, an important function of HDLs that prevents plaque progression. These unique multifunctional effects of HDL/apoA-I suggest that, if translated appropriately, have the potential to improve stent biocompatibility. This may provide an alternate and more efficacious therapeutic pathway for the translation of HDL.

A prospective randomised trial comparing the novel ridaforolimus-eluting BioNIR stent to the zotarolimus-eluting Resolute stent: six-month angiographic and one-year clinical results of the NIREUS trial

AIMS

The aim of this study was to evaluate the efficacy and safety of the BioNIR stent compared with the Resolute Integrity stent for the treatment of coronary artery disease.

METHODS AND RESULTS

This first-in-human, multicentre, single-blind randomised non-inferiority trial was performed in Europe and Israel. Patients with stable coronary artery disease or acute coronary syndromes were randomly assigned to treatment with BioNIR or Resolute Integrity stents in a 2:1 fashion. The primary endpoint was angiographic in-stent late lumen loss (LLL) at six months. Three hundred and two patients were randomised, of whom 261 (86.0%) underwent six-month angiographic follow-up. The BioNIR stent was non-inferior to the Resolute Integrity stent for the primary endpoint of in-stent LLL at six months (0.04±0.30 mm vs. 0.03±0.31 mm, respectively, pnoninferiority<0.0001). At 12-month follow-up, target lesion failure occurred in 3.4% in the BioNIR group and 5.9% in the Resolute Integrity group (p=0.22). Rates of MACE were similar between the BioNIR and Resolute Integrity groups (4.3% vs. 5.9%, respectively, p=0.45).

CONCLUSIONS

The BioNIR stent was non-inferior to the Resolute Integrity stent for the primary endpoint of angiographic in-stent LLL at six months. Clinical outcomes at one year were comparable between the two groups.

Prognostic implications of post-percutaneous coronary intervention neutrophil-to-lymphocyte ratio on infarct size and clinical outcomes in patients with acute myocardial infarction

This study evaluated the prognostic implications of post-percutaneous coronary intervention (PCI) neutrophil-to-lymphocyte ratio (NLR) in patients with acute myocardial infarction (AMI). A total of 309 patients with AMI who underwent cardiac magnetic resonance imaging (CMR) and a complete blood cell count within 24 hours before and after PCI were enrolled. Primary outcome was infarct size. Patients were assigned to high (n = 118) or low (n = 191) NLR groups according to the best cut-off value of 3.88. Infarct size (% of total left ventricular mass) was significantly higher in the high NLR group than in the low NLR group (24.1 ± 11.0 vs. 16.7 ± 9.1, p < 0.001). Post-PCI NLR ≥ 3.88 was associated with risk of a large-sized infarction (≥20%) (OR 2.91, 95% CI 1.73-4.88, p < 0.001). The risk of MACE was also significantly higher in the high NLR group than in the low NLR group (15.8% vs. 7.4%, HR 2.60, 95% CI 1.21-5.60, p = 0.015). Among patients with AMI who underwent PCI, high post-PCI NLR value was associated with higher risk of large-sized infarction as measured by CMR, as well as adverse clinical outcomes. Our findings suggest that post-PCI NLR is a useful tool for risk assessment in patients with AMI who undergo PCI.

One-year clinical outcomes of patients treated with polymer-free amphilimus-eluting stents or zotarolimus-eluting stents: A propensity-score adjusted analysis

Background

Polymer‐free amphilimus‐eluting stents (PF‐AES) represent a novel elution‐technology in coronary stenting. We aimed to assess 1‐year clinical outcomes of PF‐AES as compared to latest‐generation permanent polymer zotarolimus‐eluting stents (PP‐ZES) in a real‐world all‐comers setting.

Methods

A prospective registry of patients treated with either PF‐AES or PP‐ZES between 2014 and 2016 was conducted. The primary outcome was defined as major adverse cardiac and cerebrovascular events (MACCE), and the secondary outcome was defined as target‐lesion failure (TLF) at 1 year. To account for measured confounders, a propensity‐score adjusted Cox proportional‐hazard model was built to evaluate clinical outcomes.

Results

A total of 734 consecutive patients with 1,269 DES implantations were enrolled. The population was characterized by 28% diabetes, 24% ST‐segment elevation myocardial infarction, and a high number of complex lesions (69%). The rate of MACCE was 11.5% for PF‐AES and 13.6% for PP‐ZES, p_log‐rank = 0.11. TLF was numerically lower in PF‐AES as compared to PP‐ZES (5.4 vs. 6.1%, p_log‐rank = 0.68). After propensity‐score adjustment, PF‐AES showed a trend toward a lower rate of MACCE and a favorable rate of TLF as compared to PP‐ZES (HR 0.70; 95%CI 0.45 to 1.10, P = 0.12; and HR 0.88; 95%CI 0.47 to 1.65, P = 0.68, respectively). Rates of definite ST were low (0.8 vs. 0.3%, p_log‐rank = 0.62).

Conclusions

Our study suggests that implantation of PF‐AES was safe and effective in real‐world patients, with low‐rates of MACCE and TLF at 1 year. Our data needs to be confirmed by a large trial to evaluate the clinical outcomes of this novel polymer‐free, eluting‐technology used in PF‐AES.

Comparison of the polymer-free biolimus-coated BioFreedom stent with the thin-strut biodegradable polymer sirolimus-eluting Orsiro stent in an all-comers population treated with percutaneous coronary intervention: Rationale and design of the randomized SORT OUT IX trial

BACKGROUND

In patients with increased bleeding risk during dual antiplatelet therapy, the biolimus A9-coated BioFreedom, a stainless steel drug-coated stent devoid of polymer, has shown superiority compared to a bare-metal stent. The aim of this study was to investigate whether the polymer-free biolimus A9-coated BioFreedom is noninferior to a modern thin-strut biodegradable polymer cobalt-chromium sirolimus-eluting Orsiro stent in an all-comers patient population treated with percutaneous coronary intervention.

METHODS

The multicenter SORT OUT IX trial (NCT02623140) randomly assigned all-comers patients to treatment with the BioFreedom drug-coated stent or the biodegradable polymer Orsiro stent in 4 Danish University Hospitals. The primary end point target lesion failure is a composite of cardiac death, myocardial infarction (not related to other than index lesion), or target lesion revascularization within 12 months. Clinically driven event detection based on Danish registries will be used and continue through 5 years. Assuming an event rate of 4.2% in each stent group, 1,563 patients in each treatment arm will provide 90% power to detect noninferiority of the drug-coated BioFreedom stent with a noninferiority margin of 2.1%.

RESULTS

A total of 3,150 patients have been randomized and enrolled in the study.

CONCLUSIONS

The SORT OUT IX trial will determine whether the drug-coated BioFreedom stent is noninferior to a modern biodegradable polymer Orsiro stent.

The Search for Disease-Modifying Therapies in Pulmonary Hypertension

Pulmonary hypertension (PH) and its severe subtype pulmonary arterial hypertension (PAH) encompass a set of multifactorial diseases defined by sustained elevation of pulmonary arterial pressure and pulmonary vascular resistance leading to right ventricular failure and subsequent death. Pulmonary hypertension is characterized by vascular remodeling in association with smooth muscle cell proliferation of the arterioles, medial thickening, and plexiform lesion formation. Despite our recent advances in understanding its pathogenesis and related therapeutic discoveries, PH still remains a progressive disease without a cure. Nevertheless, development of drugs that specifically target molecular pathways involved in disease pathogenesis has led to improvement in life quality and clinical outcomes in patients with PAH. There are presently more than 12 Food and Drug Administration-approved vasodilator drugs in the United States for the treatment of PAH; however, mortality with contemporary therapies remains high. More recently, there have been exuberant efforts to develop new pharmacologic therapies that target the fundamental origins of PH and thus could represent disease-modifying opportunities. This review aims to summarize recent developments on key signaling pathways and molecular targets that drive PH disease progression, with emphasis on new therapeutic options under development.

Intravascular imaging analysis of a drug-eluting balloon followed by a bare metal stent compared to a drug-eluting stent for treatment of de novo lesions

BACKGROUND/AIMS

After a study comparing drug-eluting stents (DESs) to sequential treatment with drug-eluting balloons (DEBs) and bare metal stents (BMSs), we retrospectively analysed strut malapposition and neointimal hyperplasia in de novo coronary lesions using optical coherence tomography (OCT) or intravascular ultrasonography (IVUS).

METHODS

We obtained OCT data from 16 patients (eight per group) and IVUS data from 40 patients (20 per group). OCT or IVUS was performed after the index procedure and after 9 months. Parameters including obstruction volume due to neointimal hyperplasia (neointimal hyperplasia volume/stent volume, %), strut malapposition (% of malapposed struts), and intra-individual inhomogeneity of in-stent restenosis were compared.

RESULTS

Although obstruction volume due to neointimal hyperplasia was significantly higher in the DEB-BMS group (14.90 ± 15.36 vs. DES 7.03 ± 11.39, p = 0.025), there was no difference in strut malapposition between the two groups (DEB-BMS 1.99 ± 5.37 vs. DES 0.88 ± 2.22, p = 0.856). The DEB-BMS group showed greater intra-individual inhomogeneity of in-stent restenosis pattern than the DES group.

CONCLUSION

Treatment with DEB followed by BMS failed to improve strut malapposition despite higher in-stent neointimal growth, probably because of the inhomogeneous inhibition of in-stent neointimal hyperplasia by DEB. DEB technology should be improved to obtain even drug delivery to the vessel wall and homogeneous prevention of neointimal growth comparable to contemporary DES.

Magmaris™ resorbable magnesium scaffold: state-of-art review

Bioresorbable scaffolds (BRS) have been advocated as the ‘fourth revolution’ in interventional cardiology because they could provide temporary scaffolding and then ‘disappear’ (resorb) potentially significantly improving coronary artery disease treatment. BRS technology has gradually matured, and there are many devices available worldwide, which are currently undergoing preclinical or clinical testing. Due to the concerns related to polylactide scaffolds, magnesium alloy is now one of the most promising resorbable technologies despite available evidences on its performances in vivo are limited to small observational studies. In this state-of-art review we present Magmaris™ (Biotronik AG, Buelach, Switzerland) magnesium-based BRS from bench to bedside, reviewing to date available clinical trial data and current recommendations for its optimal use in clinical practice.

XLIMus drug eluting stent: A randomIzed controlled Trial to assess endothelialization. The XLIMIT trial

BACKGROUND

Thin strut 3rd generation drug eluting stents offer the potential advantage over the previous generation of better technical performance and reduced neointimal proliferation parameters, which are linked to mid and late term device failure.

AIM

To evaluate the performance of the Xlimus sirolimus-eluting stent (SES) against the Synergy everolimus-eluting stent (EES) in terms of device reendothelialization in patients undergoing PCI for coronary artery disease (CAD).

METHODS

XLIMIT is a multicenter randomized controlled trial targeting 180 patients requiring percutaneous coronary interventions (PCI). Patients will be treated with Xlimus SES or Synergy EES implantation and randomization will be performed in a 2:1 ratio. The primary endpoint will be the reendothelialization grade of the Xlimus stent in terms of strut coverage and neointimal hyperplasia volume as compared to Synergy. Secondary endpoints will be represented by clinical and procedural outcomes. The first patient was enrolled on February 2019.

CONCLUSIONS

A clearer understanding of the endothelialization process of new generation DES could significantly impact the treatment with dual antiplatelet therapy in the future. Moreover, although not powered for clinical end-points, the XLIMIT trial will provide randomized data in a population with minimal exclusion criteria.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03745053. Registered on November 19, 2018.

Long-Term Clinical and Angiographic Outcomes After Implantation of New-Generation Drug-Eluting Stents for Patients on Maintenance Hemodialysis

Prior research has revealed poorer clinical outcomes after drug-eluting stent (DES) implantation for hemodialysis patients. This study aims to investigate the long-term clinical and angiographic outcomes after new-generation DES implantation for hemodialysis patients.We retrospectively enrolled 91 consecutive patients (118 lesions) who underwent successful new-generation DES (everolimus-, zotarolimus-, and biolimus-eluting stents) implantation for the first time. We measured the serum calcium and phosphorus levels in the blood samples obtained just before hemodialysis. The follow-up period of clinical events was, at least, 1.5 years. In this study, major adverse cardiac and cerebrovascular events (MACCE) and clinically driven target lesion revascularization were reported in 36 (39.6%) and 11 (12.1%) patients, respectively. The prevalence of peripheral artery disease was significantly higher in the MACCE group (41.7% versus 14.5%, P = 0.006). The serum calcium level was significantly higher in the MACCE group (9.34 ± 0.92 mg/dL versus 8.77 ± 0.88 mg/dL; P = 0.004). The multivariate Cox proportional hazards model revealed that the serum calcium level (hazard ratio, 1.86; 95% confidence interval [CI]: 1.26-2.77; P = 0.002), suboptimal (over 55 mg²/dL²) calcium-phosphorus product (hazard ratio, 3.27; 95% CI: 1.41-7.61; P = 0.006) and the coexistence of peripheral artery disease (hazard ratio, 3.15; 95% CI: 1.49-6.65; P = 0.003) were independent predictors of MACCE.For hemodialysis patients, MACCE remains a frequent occurrence after new-generation DES implantation and is associated with calcium-phosphate metabolism and peripheral artery disease.

Long-term safety of bioresorbable scaffolds: insights from a network meta-analysis including 91 trials

AIMS

The aim of this study was to investigate the long-term safety and efficacy of biodegradable scaffolds and metallic stents.

METHODS AND RESULTS

We analysed a total of 91 randomised controlled trials with a mean follow-up of 3.7 years in 105,842 patients which compared two or more coronary metallic stents or biodegradable scaffolds and reported the long-term clinical outcomes (≥2 years). Network meta-analysis showed that patients treated with the Absorb bioresorbable vascular scaffold (BVS) had a significantly higher risk of definite or probable scaffold thrombosis (ScT) compared to those treated with metallic DES. The risk of very late ScT was highest with the Absorb BVS among comparators. Pairwise conventional meta-analysis demonstrated that the elevated risk of ScT with Absorb BVS compared to cobalt-chromium everolimus-eluting stents was consistent across the time points of ≤30 days (early), 31 days - 1 year (late) and >1 year (very late) ScT. In addition, target lesion failure rates were significantly higher in the Absorb BVS cohort, driven by both increased risk of target vessel myocardial infarction and ischaemia-driven target lesion revascularisation.

CONCLUSIONS

Absorb BVS implantation was associated with increased risk of long-term and very late ScT compared to current-generation metallic DES. The risk of ScT occurred with a rising trend beyond one year.

Interleukin-35 promotes early endothelialization after stent implantation by regulating macrophage activation

Background: Early strut coverage after sirolimus-eluting stent (SES) implantation is associated with the activation of inflammation, but the underlying mechanisms are not completely understood. The present study aimed to identify the relationship between the anti-inflammatory cytokine interleukin (IL) 35 (IL-35) and early strut coverage in vivo and in vitro.

Methods: We utilized a retrospective study design to measure IL-35 levels in 68 stents from 68 patients with coronary artery disease and recorded serial optical coherence tomography (OCT) images (0 and 3 months) to assess stent endothelialization. The mechanism underlying the regulatory effects of IL-35 on macrophages and human umbilical vein endothelial cells (HUVECs) was also investigated. SESs were surgically implanted into the right common carotid arteries of 200 male New Zealand White rabbits receiving intravenous injections of IL-35 or a placebo.

Results: At the 3-month OCT evaluation, complete endothelium coverage was correlated with IL-35 levels. IL-35 induced the activation of an anti-inflammatory M2-like macrophage phenotype by targeting the signal transducer and activators of transcription (STAT)1/4 signalling pathway, and IL-35-treated macrophages induced endothelial proliferation and alleviated endothelial dysfunction. IL-35-treated New Zealand White rabbits with implanted SESs showed lower percentages of cross-sections with an uncovered strut, elevated mean neointimal hyperplasia (NIH) thickness, and inhibited inflammatory responses.

Conclusions: We investigated the effect of IL-35 expression on early stent endothelialization in vivo and in vitro and identified a crucial role for IL-35 in inducing the activation of an anti-inflammatory M2-like macrophage phenotype. The present study highlights a new therapeutic strategy for early stent endothelialization.

12-Month clinical results of drug-coated balloons for de novo coronary lesion in vessels exceeding 3.0 mm

The purpose of this observational study was to investigate the feasibility, initial safety, and efficacy of the SeQuent® Please DCB (B. Braun Melsungen, Germany) for patients with de novo coronary lesions in vessels exceeding 3.0 mm in a consecutive series of all comer percutaneous coronary intervention. A total of 120 patients (135 lesions) with de novo coronary lesions in vessels ≥ 3.0 mm treated with DCB were enrolled in this single-centre prospective observational study. The primary endpoint was target lesion failure (TLF), a composite endpoint of cardiac death, target vessel-myocardial infarction (TV-MI), and clinically driven target vessel revascularization (TLR) at 12 months. Safety endpoints included cardiac death, TV-MI, and definite target vessel thrombosis. 45.9% of the lesions were classified as complex (type B2/C). The reference vessel diameter was 3.09 ± 0.31 mm measured via quantitative coronary angiography analysis. Coronary dissections occurred in 42 patients (35.0%; Type A-B 14.1%; Type C 19.1%; Type D: 1.6%), two of which [1.6%; (type D dissection)] underwent bail-out stent implantation. 12-month follow-up was completed in 100% patients. The 12-month incidence of TLF was 3.4%. The clinically driven TLR occurred in four patients (3.4%). The incidence of TLR was low in patients without any detectable dissections, similar to those with dissections (3.8% vs. 2.5%; p = 0.146). No patient suffered cardiac death, TV-MI, or target vessel thrombosis. The study shows the feasibility, initial safety, and efficacy of coronary intervention using SeQuent® Please DCB for the treatment of patients with de novo lesion in vessels exceeding 3 mm. The study highlights that the coronary dissection (Type A-C) post DCB treatment occurs frequently but is safe at follow up.

Delivery of Cell-Specific Aptamers to the Arterial Wall with an Occlusion Perfusion Catheter

Current strategies to prevent restenosis following endovascular treatment include the local delivery of anti-proliferative agents to inhibit vascular smooth muscle cell (VSMC) proliferation and migration. These agents, not specific to VSMCs, are deposited on the luminal surface and therefore target endothelial cells and delay vascular healing. Cell-targeted therapies, (e.g., RNA aptamers), can potentially overcome these safety concerns by specifically binding to VSMC and inhibiting proliferation and migration. The purpose of this study was to therefore demonstrate the ability of a perfusion catheter to deliver cell-specific RNA aptamer inhibitors directly to the vessel wall. RNA aptamers specific to VSMCs were developed using an in vitro cell-based systematic evolution of ligand by exponential enrichment selection process. Two aptamers (Apt01 and Apt14) were evaluated ex vivo using harvested pig arteries in a pulsatile flow bioreactor. Local drug delivery of the aptamers into the medial wall was accomplished using a novel perfusion catheter. We demonstrated the feasibility to deliver aptamer-based drugs directly to the medial layer of an artery using a perfusion catheter. Such cell-specific targeted therapeutic drugs provide a potentially safer and more effective treatment option for patients with vascular disease.

Combinatorial tissue engineering partially restores function after spinal cord injury

Hydrogel scaffolds provide a beneficial microenvironment in transected rat spinal cord. A combinatorial biomaterials-based strategy provided a microenvironment that facilitated regeneration while reducing foreign body reaction to the three-dimensional spinal cord construct. We used poly lactic-co-glycolic acid microspheres to provide sustained release of rapamycin from Schwann cell (SC)-loaded, positively charged oligo-polyethylene glycol fumarate scaffolds. The biological activity and dose-release characteristics of rapamycin from microspheres alone and from microspheres embedded in the scaffold were determined in vitro. Three dose formulations of rapamycin were compared with controls in 53 rats. We observed a dose-dependent reduction in the fibrotic reaction to the scaffold and improved functional recovery over 6 weeks. Recovery was replicated in a second cohort of 28 animals that included retransection injury. Immunohistochemical and stereological analysis demonstrated that blood vessel number, surface area, vessel diameter, basement membrane collagen, and microvessel phenotype within the regenerated tissue was dependent on the presence of SCs and rapamycin. TRITC-dextran injection demonstrated enhanced perfusion into scaffold channels. Rapamycin also increased the number of descending regenerated axons, as assessed by Fast Blue retrograde axonal tracing. These results demonstrate that normalization of the neovasculature was associated with enhanced axonal regeneration and improved function after spinal cord transection.

Effects of Cilostazol-Based Triple Antiplatelet Therapy Versus Dual Antiplatelet Therapy After Coronary Drug-Eluting Stent Implantation: An Updated Meta-Analysis of the Randomized Controlled Trials

BACKGROUND AND OBJECTIVE

The results of studies on cilostazol-based triple antiplatelet therapy (TAT) after drug-eluting stent (DES) implantation were inconsistent. To assess the effects of TAT compared with dual antiplatelet therapy (DAT) after DES/second-generation DES implantation, we performed a meta-analysis of randomized controlled trials (RCTs).

METHODS

All relevant studies evaluated were identified by searching the PubMed, EMBASE, Cochrane Library, and ISI Web of Science databases without time and language limitation. Subgroup analyses were performed to evaluate the efficacy and safety of TAT after second-generation DES implantation.

RESULTS

Eleven RCTs involving a total of 4684 patients were included. The meta-analysis showed TAT was associated with significant beneficial effects on angiographic findings of in-stent restenosis [risk ratio (RR) 0.645, 95% confidence interval (CI) 0.470-0.885; P = 0.007], in-segment restenosis (RR 0.606, 95% CI 0.450-0.817; P = 0.001), in-stent late loss (RR - 0.095, 95% CI - 0.136 to - 0.054; P < 0.0001), in-segment late loss (RR - 0.100, 95% CI - 0.139 to - 0.061; P < 0.0001), target lesion revascularization (TLR) (RR 0.570, 95% CI 0.430-0.755; P < 0.0001), and target vessel revascularization (TVR) (RR 0.523, 95% CI 0.380-0.719; P < 0.0001). No significant difference was found in outcomes of all-cause death, cardiac death, definite/probable stent thrombosis (ST), non-fatal myocardial infarction (MI), overall bleeding, and major bleeding between the two groups, as well as some minor adverse effects including palpitations, thrombocytopenia, neutropenia, and hepatic dysfunction. However, the incidence rate of rash, gastrointestinal disorders, and headache was significantly higher in TAT. The second-generation DES subgroup showed similar results, except for the indicators of all-cause death (RR 2.161, 95% CI 1.007-4.635; P = 0.048) and hepatic dysfunction (RR 0.176, 95% CI 0.031-0.995; P = 0.049).

CONCLUSIONS

Compared with DAT, cilostazol-based TAT can significantly improve the angiographic findings of in-stent and in-segment late loss, in-stent and in-segment restenosis, TLR, and TVR after DES/second-generation DES implantation. However, no benefits were observed in outcomes of all-cause death, cardiac death, ST, and MI.

Drug repositioning in pulmonary arterial hypertension: challenges and opportunities

Despite many advances in medical therapy for pulmonary arterial hypertension (PAH) over the past 20 years, long-term survival is still poor. Novel therapies which target the underlying pathology of PAH and which could be added to current vasodilatory therapies to halt disease progression and potentially reverse pulmonary vascular remodeling are highly sought after. Given the high attrition rates, substantial costs, and slow pace of new drug development, repositioning of “old” drugs is increasingly becoming an attractive path to identify novel treatment options, especially for a rare disease such as PAH.

We here summarize the limitations of current PAH therapy, the general concept of repurposing and repositioning, success stories of approved repositioned drugs in PAH as well as novel repositioned drugs that show promise in preclinical models of pulmonary hypertension (PH) and are currently tested in clinical trials. We furthermore discuss various data-driven as well as experimental approaches currently used to identify repurposed drug candidates and review challenges for the “repositioning community” with regards to funding and patent and regulatory considerations, and to illustrate opportunities for collaborative solutions for drug repositioning relevant to PAH.

First Report of Edge Vascular Response at 12 Months of Magmaris, A Second-Generation Drug-Eluting Resorbable Magnesium Scaffold, Assessed by Grayscale Intravascular Ultrasound, Virtual Histology, and Optical Coherence Tomography. A Biosolve-II Trial Sub-Study

INTRODUCTION AND OBJECTIVE

The edge vascular response (EVR) remains unknown in second generation drug-eluting Resorbable Magnesium Scaffold (RMS), such as Magmaris. The aim of the study was to evaluate tissue modifications in the RMS edges over time, assessed by different invasive imaging modalities.

METHODS

The patients treated with the device were assessed by optical coherence tomography (OCT), grayscale intravascular ultrasound (IVUS), and virtual histology IVUS at baseline and 12 months. The EVR study performed a segment- and frame-level analysis of the 5 mm segments proximal and distal of the actual RMS.

RESULTS

The segment-level grayscale IVUS (n = 10), virtual histology IVUS (n = 10), and OCT (n = 18) analysis did not show any significant changes after 12 months, except for a fibrous plaque area (FPA) reduction of 0.5mm² (p = 0.017) in the proximal segment compared to baseline. In the frame-level analysis, IVUS evaluation revealed a vessel area decreased 2.80 ± 1.43 mm² (p = 0.012) and 2.49 ± 1.53 mm² (p = 0.022) in 2 proximal frames. This was accompanied by plaque area reduction of 0.88 ± 0.70 mm² (p = 0.048) and a FPA decreased by 0.63 ± 0.48 mm² (p = 0.004) in one proximal frame. In 1 distal frame, there was a dense calcium area reduction of 0.10 ± 0.12 mm² (p = 0.045), FPA and fibrous fatty plaque increased 0.54 ± 0.53 mm² (p = 0.023) and 0.17 ± 0.16 mm² (p = 0.016), respectively. By OCT, there was a lumen area decrease of 0.76 ± 1.51 mm² (p = 0.045) in a distal frame.

CONCLUSION

At 12 months, Magmaris EVR assessment does not show overall significant changes, except for a fibrous plaque area reduction in the proximal segment. This could be translated as a benign healing process at the edges of the RMS.

SUMMARY

The edge vascular response (EVR) remains unknown in second generation drug-eluting absorbable metal scaffolds (RMS), such as Magmaris. Patients treated with the device were assessed by multi invasive imaging modalities [i.e. optical coherence tomography (OCT), grayscale intravascular ultrasound (IVUS), and virtual histology IVUS] evaluating the tissue changes over time in the segment- and frame-level analysis of the 5 mm segments proximal and distal of the actual RMS. As a result, after 12 months, Magmaris EVR assessment does not show overall significant changes, except for a fibrous plaque area reduction in the proximal segment, translating a benign healing process at the edges of the RMS.

Leveraging Cumulative Network Meta-analysis and Value of Information Analysis to Understand the Evolving Value of Medical Research

BACKGROUND

Leveraging cumulative network meta-analysis (NMA) and value of information (VOI) analysis, this article aims to understand the evolving value of medical research and to identify gaps in the evidence for future research.

METHODS

As an illustration, we identified 31 randomized controlled trials (RCT) from 1980 to 2013 that examined a network of 3 interventions for coronary artery disease: medical therapy (MED), percutaneous coronary intervention (PCI), and coronary artery bypass graft (CABG) surgery. We conducted Bayesian NMA to combine evidence from a new RCT with existing knowledge. Then, using the Duke Databank for Cardiovascular Diseases database, we developed an accelerated failure time model to estimate the joint effects of patient characteristics and treatment choices on survival outcomes. With the estimated coefficients and covariance matrices, we projected survival benefits and its surrounding uncertainty among 50,000 simulated patients treated with MED, PCI, or CABG. The value of resolving residual uncertainty from future trials was quantified through the VOI analysis. We repeated these steps for each published RCT to estimate dynamic changes in VOI estimates.

RESULTS

Our cumulative NMA found that CABG conferred a lower, but not statistically significant, mortality than PCI (hazard ratio [HR], 0.90; 95% uncertainty interval, 0.80-1.05). MED had a nonsignificantly higher long-term mortality than PCI (HR, 1.11; 0.98-1.31) but significantly higher than CABG (HR, 1.07; 1.23-1.41). The greatest potential gains from future research would come from additional head-to-head trials between CABG v. PCI with the value of future research equaling 0.27 life years per patient.

CONCLUSIONS

The combination of cumulative NMA and VOI approaches can improve the efficiency of comparative effectiveness research by using all of the available evidence to determine future research priorities.

Rapamycin: A Bacteria-Derived Immunosuppressant That Has Anti-atherosclerotic Effects and Its Clinical Application

Atherosclerosis (AS) is the leading cause of stroke and death worldwide. Although many lipid-lowering or antiplatelet medicines have been used to prevent the devastating outcomes caused by AS, the serious side effects of these medicines cannot be ignored. Moreover, these medicines are aimed at preventing end-point events rather than addressing the formation and progression of the lesion. Rapamycin (sirolimus), a fermentation product derived from soil samples, has immunosuppressive and anti-proliferation effects. It is an inhibitor of mammalian targets of rapamycin, thereby stimulating autophagy pathways. Several lines of evidence have demonstrated that rapamycin possess multiple protective effects against AS through various molecular mechanisms. Moreover, it has been used successfully as an anti-proliferation agent to prevent in-stent restenosis or vascular graft stenosis in patients with coronary artery disease. A thorough understanding of the biomedical regulatory mechanism of rapamycin in AS might reveal pathways for retarding AS. This review summarizes the current knowledge of biomedical mechanisms by which rapamycin retards AS through action on various cells (endothelial cells, macrophages, vascular smooth muscle cells, and T-cells) in early and advanced AS and describes clinical and potential clinical applications of the agent.

Influence of Dissolution Vessel Geometry and Dissolution Medium on In Vitro Dissolution Behaviour of Triamterene-Coated Model Stents in Different Test Setups

The aim of this study was to investigate if the geometry of the dissolution vessel, the dissolution medium volume and composition might contribute to the variation in drug release from drug-eluting stents (DES) in different test setups, which has been observed in previous in vitro studies. Therefore, DES containing triamterene as model substance were produced via fluidised-bed technology. Dissolution testing was carried out using different incubation setups, the reciprocating holder (USP Apparatus 7) and two flow-through methods, a method similar to the USP Apparatus 4 (FTC) and the vessel-simulating flow-through cell (vFTC) equipped with a hydrogel as a second compartment simulating the blood vessel wall. The results indicate that dissolution vessel geometry and medium volume had no influence on the release behaviour and only the flow-through cell methods yielded a lower dissolution rate than the incubation setups (80.6 ± 2.0% released in the FTC after 14 days compared to > 90% for all incubation setups). The composition of the hydrogel used in the vFTC also affected the dissolution rate (53.9 ± 4.5% within 14 days with a hydrogel based on phosphate-buffered saline compared to 78.2 ± 1.2% obtained with a hydrogel based on water) possibly due to different solubility of triamterene in the release media as well as interactions between the coating polymer and the release medium. Hence, the introduction of a hydrogel as a second compartment might lead to a more biorelevant test setup.

The presence of late potentials after percutaneous coronary intervention for the treatment of acute coronary syndrome as a predictor for future significant cardiac events resulting in re-hospitalization

INTRODUCTION

We previously reported that LP positive patients after percutaneous coronary intervention (PCI) had higher rate of re-hospitalization in the small-scale study (135 patients). In this study, we evaluated correlation between LP and later cardiac events leading to re-hospitalization more extensively in greater population.

METHODS AND RESULTS

A 24-h high-resolution (HR) ambulatory electrocardiogram (ECG) was performed in 421 patients that received PCI for the treatment of acute coronary syndrome (ACS) within 30 days. Various baseline characteristics and post-PCI ECG parameters including LP were examined for correlation with later re-hospitalization. LP was evaluated based on 3 different conditions, i.e., the worst, mean and best values, from 24-h signal-averaged QRS wave data. During the post-PCI follow-up period (611 ± 489.0 days), 90 patients were re-hospitalized due to cardiac events. Multivariate analysis identified only positive LP based on the worst value as an independent predictor for re-hospitalization with OR 2.26. Most of re-hospitalization cases (>75%) were predominantly attributed to ischemic events. LP positive population had significantly higher incidences of ischemic events as well as overall re-hospitalization compared to LP negative population. The predictive power of LP was decreased when it was combined with other variables. The receiver operating characteristic analysis determined the LP cut-off values consistent with the LP positive criteria previously reported and standardized.

CONCLUSION

The presence of LP in the 24-h HR ambulatory ECG post-PCI was an independent predictor for a risk of re-hospitalization due to ischemic cardiac events in ACS patients.

Optical Coherence Tomography in In-Stent Restenosis: A Challenge Made Easier

In-stent restenosis (ISR) has been an area of concern for the interventional cardiologists since the era of bare-metal stents (BMS). Although the incidence of ISR is more with BMS as compared to drug-eluting stents, due to the underlying pathophysiological differences, between the two; the latter has a more accelerated course and is difficult to treat. In this case report, we try to address this issue of difficult treatment of ISR and the benefit of using optical coherence tomography in these situations.

Angioplasty versus stenting for infrapopliteal arterial lesions in chronic limb-threatening ischaemia

BACKGROUND

Chronic limb-threatening ischaemia (CLTI) is a manifestation of peripheral arterial disease (PAD) that includes chronic ischaemic rest pain or ischaemic skin lesions, ulcers, or gangrene for longer than two weeks. The severity of the disease depends on the extent of arterial stenosis and the availability of collateral circulation. Treatment for CLTI aims to relieve ischaemic pain, heal ischaemic ulcers, prevent limb loss, improve quality of life, and prolong survival. CLTI due to occlusive disease in the infrapopliteal arterial circulation (below-knee circulation) can be treated via an endovascular technique by a balloon opening the narrowed vessel, so called angioplasty, with or without the additional deployment of a scaffold made of metal alloy or other material, so called stenting. Endovascular interventions in the infrapopliteal vasculature may improve symptoms in patients with CLTI by re-establishing in-line blood flow to the foot. Controversy remains as to whether a balloon should be used alone to open the vessel, or whether a stent should also be deployed.

OBJECTIVES

To determine the efficacy and safety of percutaneous transluminal angioplasty (PTA) alone versus PTA with stenting of infrapopliteal arterial lesions (anterior tibial artery, posterior tibial artery, fibular artery (formerly known as peroneal artery), and common tibioperoneal trunk) for patients with chronic limb-threatening ischaemia (CLTI).

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, and AMED databases, as well as World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 25 June 2018. We applied no language restrictions.

SELECTION CRITERIA

We planned to include randomised or quasi-randomised controlled trials comparing PTA versus PTA with a stent and including patients aged 18 years or over with CLTI. We defined CLTI as Fontaine stage III (ischaemic rest pain) and IV (ischaemic ulcers or gangrene) or consistent with Rutherford category 4 (ischaemic rest pain), 5 (minor tissue loss), and 6 (major tissue loss), with stenotic (> 50% luminal loss) or occluded infrapopliteal artery, including tibiofibular trunk, anterior tibial artery, posterior tibial artery, and fibular artery. We included all types of stents irrespective of design (e.g. bare-metal, drug-eluting, bio-absorbable).

DATA COLLECTION AND ANALYSIS

Two review authors (CC-TH and GNCK) independently selected suitable trials, assessed trial quality, and extracted data. An additional third review author (MLvD) assessed trial quality and, when necessary, acted as arbiter for study selection and data extraction. Outcomes included technical success of the procedure, procedural complications, patency, major amputation, and mortality. We assessed the quality of evidence using the GRADE approach.

MAIN RESULTS

We included in the review seven trials with 542 participants. One trial randomised limbs to undergo PTA alone or PTA with stent placement, and the remaining studies randomised participants. Five trials with 476 participants show that the technical success rate was greater in the stent group than in the angioplasty group (odds ratio (OR) 3.00, 95% confidence interval (CI) 1.14 to 7.93; 476 lesions; 5 studies; I² = 23%). Meta-analysis of three eligible trials with 456 participants did not show a clear difference in short-term (within six months) patency between infrapopliteal arterial lesions treated with PTA and those treated with PTA and stenting (OR 0.88, 95% CI 0.37 to 2.11; 456 lesions; 3 studies; I² = 77%). Results also did not show clear differences between treatment groups in procedure complication rate (OR 0.87, 95% CI 0.01 to 53.60; 360 participants; 5 studies; I² = 85%), rate of major amputations at 12 months (OR 1.34, 95% CI 0.56 to 3.22; 306 participants; 4 studies; I² = 0%), and rate of mortality at 12 months (OR 0.71, 95% CI 0.43 to 1.17; 497 participants; 6 studies; I² = 0%). Heterogeneity between studies was high for the outcomes procedure complications and primary patency. The overall methodological quality of the trials included in this review was moderate due to selection and performance bias. Studies used different regimens for pretreatment and post-treatment antiplatelet/anticoagulant medication. We downgraded the certainty of the overall evidence for all outcomes by one level to moderate due to inconsistency of results across studies and large confidence intervals (small numbers of trials and participants).

AUTHORS' CONCLUSIONS

Trials show that the immediate technical success rate of restoring luminal patency is higher in the stent group but reveal no clear differences in short-term patency at six months between infrapopliteal arterial lesions treated with PTA with stenting versus those treated with PTA without stenting. We ascertained no clear differences between groups in periprocedural complications, major amputation, and mortality. However, use of different regimens for pretreatment and post-treatment antiplatelet/anticoagulant medication and the duration of its use within and between trials may have influenced the outcomes. Limited currently available data suggest that high-quality evidence is insufficient to show that PTA with stent insertion is superior to use of standard PTA alone without stenting for treatment of infrapopliteal arterial lesions. Further studies should standardise the use of antiplatelets/anticoagulants before and after the intervention to improve the comparability of the two treatments.