A registry-based study of paclitaxel drug-coated balloon angioplasty for the treatment of in-stent restenosis of the femoral-popliteal artery

OBJECTIVE

The aim of this study was to report the results of a prospective, single-arm, registry-based study assessing the safety and performance of a paclitaxel drug-coated balloon (DCB) for the treatment of superficial femoral artery (SFA) or popliteal artery in-stent restenosis (ISR) in a United States population.

METHODS

We conducted a prospective, non-randomized, multi-center, single-arm, post-market registry of the IN.PACT Admiral DCB for the treatment of ISR lesions in the SFA or popliteal artery at 43 sites within the Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) Registry from December 2016 to January 2020. Clinical outcomes were assessed at 12, 24, and 36 months. The primary endpoint was target lesion revascularization at 12 months. Secondary endpoints included technical success, target vessel revascularization, major limb amputation, and all-cause mortality. Results are presented as survival probabilities based on Kaplan-Meier survival estimates.

RESULTS

Patients (N = 300) were 58% male, with a mean age of 68 ± 10 years. Diabetes was present in 56%, 80% presented with claudication, and 20% with rest pain. Lesions included ISR of the SFA in 68%, SFA-popliteal in 26%, and popliteal arteries in 7%. The mean lesion length was 17.8 ± 11.8 cm. Lesions were categorized as occlusions in 43% (mean occluded length, 16 ± 10 cm). TASC type was A (17%), B (29%), C (38%), and D (15%). Technical success was 99%. Re-stenting was performed in 5% and thrombolysis in 0.6% of patients. Kaplan-Meier estimates for freedom from target lesion revascularization were 90%, 72%, and 62% at 12, 24, and 36 months. Freedom from target vessel revascularization was 88%, 68%, and 59% and freedom from major target limb amputation was 99.6%, 98.9%, and 98.9%, respectively, at 12, 24, and 36 months. Survival was 95%, 89%, and 85% at 12, 24, and 36 months.

CONCLUSIONS

This post-market registry-based study shows promising results in treating femoral-popliteal ISR with paclitaxel DCB in comparison to the results of plain balloon angioplasty reported in the literature. These results demonstrate the ability of the SVS VQI to conduct post-market evaluation of peripheral devices in partnership with industry and federal regulators.

The role of exercise-based cardiac rehabilitation after percutaneous coronary intervention in patients with coronary artery disease: a meta-analysis of randomised controlled trials

BACKGROUND

this study was designed to analyse patient outcomes using a combination of PCI and exercise-based cardiac rehabilitation compared with PCI alone.

METHODS

PCI can improve the survival rate of patients with coronary artery disease, but it can also cause vascular endothelial cell injury, thrombosis, and even restenosis. Early cardiac rehabilitation exercise is crucial for patients with coronary heart disease after PCI. Five databases were examined for randomised controlled trials involving early cardiac rehabilitation exercise and standard treatment in patients with coronary heart disease after PCI. The search period lasted from the creation of the database (2006) until December 2022. The outcomes including angina, arrhythmia, coronary restenosis, left ventricular ejection fraction, left ventricular end diastolic diameter, 6-min walk distance, total cholesterol, heart rate, systolic blood pressure and diastolic blood pressure. RevMan 5.3 was used to analyse the data, and the Cochrane Collaboration was used to assess the quality of evidence.

RESULTS

A total of 1231 patients were enrolled in this study. Angina pectoris (RR = 0.24, 95% CI [0.10, 0.57], p = 0.001), Arrhythmia (RR = 0.17, 95% CI [0.05, 0.55], p = 0.003), Coronary artery restenosis (RR = 0.10, 95% CI [0.01, 0.76], p = 0.03).

CONCLUSION

Exercise after PCI improves LVEF, enhances 6MWD, lowers HR and minimises the risk of angina, arrhythmia and coronary artery restenosis in CHD patients. Exercise had no discernible effect on LVEDD, TC, SBP, or DBP.

A physics-informed deep learning framework for modeling of coronary in-stent restenosis

Machine learning (ML) techniques have shown great potential in cardiovascular surgery, including real-time stenosis recognition, detection of stented coronary anomalies, and prediction of in-stent restenosis (ISR). However, estimating neointima evolution poses challenges for ML models due to limitations in manual measurements, variations in image quality, low data availability, and the difficulty of acquiring biological quantities. An effective in silico model is necessary to accurately capture the mechanisms leading to neointimal hyperplasia. Physics-informed neural networks (PINNs), a novel deep learning (DL) method, have emerged as a promising approach that integrates physical laws and measurements into modeling. PINNs have demonstrated success in solving partial differential equations (PDEs) and have been applied in various biological systems. This paper aims to develop a robust multiphysics surrogate model for ISR estimation using the physics-informed DL approach, incorporating biological constraints and drug elution effects. The model seeks to enhance prediction accuracy, provide insights into disease progression factors, and promote ISR diagnosis and treatment planning. A set of coupled advection-reaction-diffusion type PDEs is constructed to track the evolution of the influential factors associated with ISR, such as platelet-derived growth factor (PDGF), the transforming growth factor- β (TGF- β ), the extracellular matrix (ECM), the density of smooth muscle cells (SMC), and the drug concentration. The nature of PINNs allows for the integration of patient-specific data (procedure-related, clinical and genetic, etc.) into the model, improving prediction accuracy and assisting in the optimization of stent implantation parameters to mitigate risks. This research addresses the existing gap in predictive models for ISR using DL and holds the potential to enhance patient outcomes through predictive risk assessment.

Natural history of superior mesenteric artery in-stent restenosis

OBJECTIVE

Superior mesenteric artery (SMA) stenting is the preferred approach for patients with symptomatic SMA-associated chronic mesenteric ischemia (CMI). The durability of this modality is impacted by in-stent restenosis (ISR). Duplex ultrasound (DUS) and computed tomographic angiography (CTA)-measured ISR may be weakly correlated and not uniformly associated with recurrence of presenting symptoms. This study aims to analyze the association between the degree of ISR for patients with CMI and to develop a predictive model for symptom recurrence.

METHODS

Single center, retrospective study included all patients with CMI with SMA stents from the period of 2003 to 2020. Follow-up period analysis included patients' symptoms recurrence, DUS, CTA, and angiography. A receiver operating characteristic (ROC) analysis was used to evaluate whether peak systolic velocity (PSV) was predictive of symptom recurrence. A subgroup analysis of patients (asymptomatic and symptomatic) with SMA ISR was identified; restenosis defined by DUS with peak systolic velocity (PSV) ≥350.

RESULTS

The study included 186 patients with the ROC analysis obtained from 503 postoperative visits. PSV was not a predictor of symptoms return with area under the curve (AUC) = 0.49 (95% confidence interval [CI], 0.40-0.57). Agreement analysis between imaging modalities showed higher agreement between CTA and angiogram (AUC, 0.769; 95% CI, 0.688-0.849) vs CTA and DUS (AUC, 0.650; 95% CI, 0.589-0.711). The subgroup analysis of patients with ISR included 99 patients (asymptomatic n = 67; symptomatic n = 32). There was no statistical difference between median time (months) to ISR between both groups: 4.5 (asymptomatic group) and 7.6 (symptomatic group). The use of preoperative antiplatelet (86% vs 65%; P = .015) and P2Y12 receptor blockers (36% vs 13%; P = .016) was more prevalent in the asymptomatic group. There was no difference between the type or number of stents placed, stent diameter, or concomitant celiac artery intervention between both groups.

CONCLUSIONS

The natural history of SMA and multimodality defined ISR in CMI has not previously been described. Elevated PSV was a poor predictor of symptoms recurrence. Both asymptomatic and symptomatic patients with ISR did not differ in type of stent placed, time to ISR, or involvement of celiac artery. Antiplatelet use pre- and postoperatively appears protective against symptoms recurrence. Our findings underscore the need for long-term surveillance integrating clinical evaluation and multimodality imaging when indicated.

[OCT analysis of in-stent neointima over 5 years post-DES implantation]

Objective: To investigate the characteristics of neointimal hyperplasia (NIH) in patients with in-stent restenosis (ISR) over 5 years post-drug-eluting stent (DES) implantation based on optical coherence tomography (OCT). Methods: In this cross-sectional study, patients with DES-ISR who underwent OCT examination at PLA General Hospital between March 2010 and March 2022 were retrospectively included. All patients were divided into≤5 years DES-ISR group and>5 years DES-ISR group according to the time interval after DES implantation. Quantitative and qualitative analyses were conducted on OCT images to compare the clinical data and lesion characteristics of two patient groups. Furthermore, the independent clinical predictive factors of in-stent neoatherosclerosis (ISNA) were analyzed by multivariable logistic regression. Results: A total of 230 DES-ISR patients with 249 lesions were included, with an age of (63.1±10.4) years and 188 males (81.7%). The median interval after DES implantation was 6 (2, 9) years. There were 117 patients (122 ISR lesions) in the≤5 years DES-ISR group, and 113 patients (127 ISR lesions) in the>5 years DES-ISR group. Compared with≤5 years DES-ISR,>5 years DES-ISR showed more heterogeneous patterns (65.4% (83/127) vs. 48.4% (59/122), P=0.007), diffuse patterns (46.5% (59/127) vs. 31.2% (38/122), P=0.013), macrophage accumulations (44.1% (56/127) vs. 31.2% (38/122), P=0.035) in NIH and higher prevalence of ISNA (83.5% (106/127) vs. 72.1% (88/122), P=0.031). According to multivariable logistic regression, the independent predictive factor for ISNA was female (OR=0.44, 95%CI 0.21-0.90, P=0.026). Female (OR=0.48, 95%CI 0.23-0.99, P=0.046) and low-density lipoprotein cholesterol level (OR=1.62, 95%CI 1.01-2.59, P=0.046) were independent predictive factors, respectively, for lipid ISNA. Calcified ISNA was independently associated with time interval of post-DES implantation (OR=1.18, 95%CI 1.07-1.29, P=0.001). Conclusion: DES-ISR patients with a time interval of>5 years after stent implantation have a higher prevalence of ISNA and more complex lesions. Gender, the level of low-density lipoprotein cholesterol, and the time interval post-DES implantation are independently correlated with ISNA, lipid ISNA, and calcified ISNA.

Ultrasound-mediated delivery of Pik3cb shRNA using magnetic nanoparticles for the treatment of in-stent restenosis in a rat balloon-injured model

The aim of the present work was to examine the effect of polyethylene glycol (PEG)-coated superparamagnetic iron oxide (SPIO) nanoparticles carrying Pik3cb short hairpin RNA (shRNA) in the prevention of restenosis with the aid of ultrasound and a magnetic field. SPIO is a type of contrast agent used in medical imaging to enhance the visibility of specific tissues or organs. It consists of tiny iron oxide nanoparticles that can be targeted to specific areas of interest in the body. PEG-coated SPIO nanoparticles carrying Pik3cb shRNA (SPIO-shPik3cb) were prepared, and the particle size and zeta potential of PEG-coated SPIO nanoparticles with and without Pik3cb shRNA were examined. After a right common artery balloon-injured rat model was established, the rats were randomly divided into four groups, and the injured arteries were transfected with SPIO-shPik3cb, saline, SPIO-shcontrol and naked shRNA Pik3cb. During the treatment, each group was placed under a magnetic field and was transfected with the aid of ultrasound. Rats were sacrificed, and the tissue was harvested for analysis after 14 days. The results suggested that the mean particle size and zeta potential of SPIO-shPik3cbs were 151.45 ± 11 nm and 10 mV, respectively. SPIO-shPik3cb showed higher transfection efficiency and significantly inhibited the intimal thickening compared with naked Pik3cb shRNA in vascular smooth muscle cells (VSMCs) (*P < 0.05). Moreover, SPIO-shPik3cb could also significantly downregulate the expression of pAkt protein compared with naked Pik3cb shRNA. According to the results, SPIO-shPik3cb can remarkably inhibit the intimal thickening under a combination of magnetic field exposure and ultrasound.

Comparison of Clinical Outcomes Among Various Percutaneous Coronary Intervention Strategies for Small Coronary Artery Disease

It remains unclear which percutaneous coronary intervention (PCI) strategy is the most preferable in patients with small-vessel coronary artery disease (CAD). We sought to evaluate the clinical efficacy of various PCI strategies for patients with small-vessel CAD through a network meta-analysis of randomized controlled trials (RCTs). We searched multiple databases for RCTs investigating the efficacy of the following PCI strategies for small-vessel CAD (<3 mm in diameter): drug-coated balloons (DCB), early-generation paclitaxel-eluting stents and sirolimus-eluting stents (SES), newer-generation drug-eluting stents (DES), bare-metal stents (BMS), cutting balloon angioplasty, and balloon angioplasty (BA). The primary outcome was the trial-defined major adverse cardiovascular events (MACE), mostly defined as a composite of death, myocardial infarction, and revascularization. The secondary outcomes included each component of MACE and angiographic binary restenosis. We performed a sensitivity analysis for RCTs without BMS or first-generation DES. Our search identified 29 eligible RCTs, including 8,074 patients among the 8 PCI strategies. SES significantly reduced MACE compared with BA (hazard ratio 0.23, 95% confidence interval 0.10 to 0.54) with significant heterogeneity (I2 = 55.9%), and the rankogram analysis showed that SES was the best. There were no significant differences between DCB and newer-generation DES in any clinical outcomes, which was consistent in the sensitivity analysis. BMS and BA were ranked as the worst 2 for most clinical outcomes. In conclusion, SES was ranked as the best for reducing MACE. There were no significant differences in clinical outcomes between DCB and newer-generation DES. BMS and BA were regarded as the worst strategies for small-vessel CAD.

Preliminary Investigation on Efficacy and Safety of Substance P-Coated Stent for Promoting Re-Endothelialization: A Porcine Coronary Artery Restenosis Model

BACKGROUND

Current polymer-based drug-eluting stents (DESs) have fundamental issues about inflammation and delayed re-endothelializaton of the vessel wall. Substance-P (SP), which plays an important role in inflammation and endothelial cells, has not yet been applied to coronary stents. Therefore, this study compares poly lactic-co-glycolic acid (PLGA)-based everolimus-eluting stents (PLGA-EESs) versus 2-methacryloyloxyethyl phosphorylcholine (MPC)-based SP-eluting stents (MPC-SPs) in in-vitro and in-vivo models.

METHODS

The morphology of the stent surface and peptide/drug release kinetics from stents were evaluated. The in-vitro proliferative effect of SP released from MPC-SP is evaluated using human umbilical vein endothelial cell. Finally, the safety and efficacy of the stent are evaluated after inserting it into a pig's coronary artery.

RESULTS

Similar to PLGA-EES, MPC-SP had a uniform surface morphology with very thin coating layer thickness (2.074 μm). MPC-SP showed sustained drug release of SP for over 2 weeks. Endothelial cell proliferation was significantly increased in groups treated with SP (n = 3) compared with the control (n = 3) and those with everolimus (n = 3) (SP: 118.9 ± 7.61% vs. everolimus: 64.3 ± 12.37% vs. the control: 100 ± 6.64%, p < 0.05). In the animal study, the percent stenosis was higher in MPC-SP group (n = 7) compared to PLGA-EES group (n = 7) (MPC-SP: 28.6 ± 10.7% vs. PLGA-EES: 16.7 ± 6.3%, p < 0.05). MPC-SP group showed, however, lower inflammation (MPC-SP: 0.3 ± 0.26 vs. PLGA-EES: 1.2 ± 0.48, p < 0.05) and fibrin deposition (MPC-SP: 1.0 ± 0.73 vs. PLGA-EES: 1.5 ± 0.59, p < 0.05) around the stent strut. MPC-SP showed more increased expression of cluster of differentiation 31, suggesting enhanced re-endothelialization.

CONCLUSION

Compared to PLGA-EES, MPC-SP demonstrated more decreased inflammation of the vascular wall and enhanced re-endothelialization and stent coverage. Hence, MPC-SP has the potential therapeutic benefits for the treatment of coronary artery disease by solving limitations of currently available DESs.

Computational modeling of in-stent restenosis: Pharmacokinetic and pharmacodynamic evaluation

Persistence of the pathology of in-stent restenosis even with the advent of drug-eluting stents warrants the development of highly resolved in silico models. These computational models assist in gaining insights into the transient biochemical and cellular mechanisms involved and thereby optimize the stent implantation parameters. Within this work, an already established fully-coupled Lagrangian finite element framework for modeling the restenotic growth is enhanced with the incorporation of endothelium-mediated effects and pharmacological influences of rapamycin-based drugs embedded in the polymeric layers of the current generation drug-eluting stents. The continuum mechanical description of growth is further justified in the context of thermodynamic consistency. Qualitative inferences are drawn from the model developed herein regarding the efficacy of the level of drug embedment within the struts as well as the release profiles adopted. The framework is then intended to serve as a tool for clinicians to tune the interventional procedures patient-specifically.

[Correlation between C-reactive protein to albumin ratio and restenosis after femoral popliteal stenting in patients with lower extremity arteriosclerotic obliterans]

Objective: To investigate the study of the correlation between C-reactive protein to albumin ratio (CAR) and restenosis after stenting in patients with lower extremity atherosclerotic occlusive disease(LEASO). Methods: The clinical data of 95 patients with LEASO admitted to the Department of Vascular Surgery of Nanjing Drum Tower Hospital from June 2020 to December 2022 were retrospectively analyzed. There were 67 males and 28 females,aged (73.1±9.4) years (range:51 to 92 years). The patients were classified into the restenosis group (n=61) and the patency group (n=34) according to the CT angiography results. Independent sample t test,Mann-Whitney U test and χ2 test were used to compare the data between two groups. Risk factors for restenosis after femoropopliteal artery stenting in patients with LEASO were analyzed using multivariate Cox regression. The relationship between preoperative CAR level and restenosis after stent placement was analyzed. Subject operating characteristic(ROC) curves of CAR were plotted to assess the predictive value of CAR for restenosis after stenting,and the results were expressed as area under the curve (AUC). Results: The aortoiliac calcification grade,number of stents,length of stents,C-reactive protein and CAR levels in restenosis group were higher than those in the patency group,and the serum albumin level was lower than that in the patency group(all P<0.05). And the results of multifactorial Cox regression analysis showed that higher pre-procedure CAR level and lower ABI value was an independent risk factor for in-stent restenosis. The AUC of the ROC curve for restenosis was 0.737(95%CI:0.617 to 0.856),the AUC of the ROC curve for 12-month restenosis was 0.709(95%CI:0.602 to 0.815), and the AUC of the ROC curve for 24-month restenosis was 0.702(95%CI:0.594 to 0.811). Conclusion: Higher pre-procedural CAR levels in patients with LEASO is risk factor for in-stent restenosis,and CAR has a predictive value for restenosis after lower extremity arterial stent dilatation and angioplasty.

Changes of plasma Rap1A levels in patients with in-stent restenosis after percutaneous coronary intervention and the underlying mechanisms

OBJECTIVES

Percutaneous coronary intervention (PCI) is one of the most important treatments for coronary artery disease (CAD). However, in-stent restenosis (ISR) after PCI is a serious complication without effective measures for prevention and treatment. This study aims to investigate the Ras-related protein 1A (Rap1A) level in ISR patients and in the tumor necrosis factor-α (TNF-α)-induced inflammatory injury model of human umbilical vein endothelial cells (HUVECs), to explore the role of Rap1A in regulating TNF-α-induced inflammation in HUVECs and to provide a new potential target for ISR prevention and treatment.

METHODS

A total of 60 CAD patients, who underwent PCI between December 2020 and July 2022 from the Department of Cardiovascular Medicine of Xiangya Hospital, Central South University, and re-examined coronary angiography (CAG) 1 year after the operation, were included. After admission, 27 patients were diagnosed with ISR and 33 patients were diagnosed with non-in-stent restenosis (non-ISR) according to the CAG. Clinical data were collected, and the plasma Rap1A level was determined by enzyme linked immunosorbent assay (ELISA). In cell experiments, an inflammatory injury model was established with TNF-α treatment (10 ng/mL, 24 h) in HUVECs. The mRNA and protein expression levels of Rap1A, interlukin-6 (IL-6), and vascular cell adhesion molecule-1 (VCAM-1) were measured by real-time reverse transcription PCR and Western blotting. Small interfering RNA (siRNA) was used to explore the role of Rap1A in regulating TNF-α-induced inflammation in HUVECs.

RESULTS

Compared with the non-ISR patients, a higher proportion of ISR patients had a history of smoking (P=0.005) and diabetes (P=0.028), and higher levels of glycosylated hemoglobin (HbA1c) (P=0.012), low-density lipoprotein cholesterol (LDL-c) (P=0.014), and hypersensitive C-reactive protein (hs-CRP) (P=0.027). The remaining projects did not show significant differences (all P>0.05). The plasma level of Rap1A in the ISR group was significantly higher than that in the non-ISR group [942.14 (873.28 to 1 133.81) μg/mL vs 886.93 (812.61 to 930.98) μg/mL; P=0.004]. Diabetes, LDL-c, and Rap1A were risk factors for ISR by univariate logistic regression analysis (all P<0.05). The mRNA and protein expression levels of inflammatory factors IL-6 and VCAM-1 were increased in HUVECs after 10 ng/mL TNF-α treatment for 24 h compared with the control group (all P<0.05), while the mRNA and protein levels of Rap1A were increased (both P<0.05). After inhibition of Rap1A in HUVECs, the mRNA and protein expression levels of IL-6 and VCAM-1 were significantly decreased (all P<0.05).

CONCLUSIONS

The plasma Rap1A level was significantly elevated in patients with ISR, suggesting that Rap1A may be a potential biomarker for predicting ISR. In the TNF-α- induced HUVECs inflammatory injury model, the expression level of Rap1A was increased. The level of TNF-α-induced endothelial cell inflammation was decreased after inhibition of Rap1A expression, suggesting that Rap1A may be a potential target for the treatment of endothelial cell inflammation in ISR.

Increased prescription dose for large vessel intravascular brachytherapy

BACKGROUND

Most randomized studies testing the effectiveness of IVBT were limited to vessels less than 4 mm diameter. In fact, it is now common to treat vessels larger than 4 mm. Accordingly, the authors instituted a prescription dose increase to 34 Gy at 2 mm from source center for vessels greater than 4.0 mm. The increase in prescription dose to 34 Gy at 2 mm from center is substantial, being 50% higher than the conventional maximum of 23 Gy.

AIM

To take a close look at group of patients treated to 34 Gy, and for whom follow-up angiograms are available.

METHODS

Ten patients treated for ISR with a prescription dose of 34 Gy and for whom follow-up angiograms were available were studied. Beta-radiation brachytherapy was performed with a Novoste Beta-Cath System using a strontium-90 (beta) source (Best Vascular, Springfield, VA). Source lengths of 40 or 60 mm were used. A dose of 34 Gy was prescribed at 2 mm from the source center.

RESULTS

Patients were re-catheterized from 2 to 21 months (median: 16 months) following IVBT, all for symptoms suggested of restenosis. All patients had some degree of ISR of the target vessel, but no IVBT-treated vascular segment showed angiographic signs of degeneration, dissection or aneurysm.

CONCLUSION

The authors' clinical impression, along with detailed review of the 10 cases, suggest that using a 34 Gy prescription dose at 2 mm from source center does not result in increased toxicity.

Investigating the effect of drug release on in-stent restenosis: A hybrid continuum - agent-based modelling approach

BACKGROUND AND OBJECTIVE

In-stent restenosis (ISR) following percutaneous coronary intervention with drug-eluting stent (DES) implantation remains an unresolved issue, with ISR rates up to 10%. The use of antiproliferative drugs on DESs has significantly reduced ISR. However, a complete knowledge of the mechanobiological processes underlying ISR is still lacking. Multiscale agent-based modelling frameworks, integrating continuum- and agent-based approaches, have recently emerged as promising tools to decipher the mechanobiological events driving ISR at different spatiotemporal scales. However, the integration of sophisticated drug models with an agent-based model (ABM) of ISR has been under-investigated. The aim of the present study was to develop a novel multiscale agent-based modelling framework of ISR following DES implantation.

METHODS

The framework consisted of two bi-directionally coupled modules, namely (i) a drug transport module, simulating drug transport through a continuum-based approach, and (ii) a tissue remodelling module, simulating cellular dynamics through an ABM. Receptor saturation (RS), defined as the fraction of target receptors saturated with drug, is used to mediate cellular activities in the ABM, since RS is widely regarded as a measure of drug efficacy. Three studies were performed to investigate different scenarios in terms of drug mass (DM), drug release profiles (RP), coupling schemes and idealized vs. patient-specific artery geometries.

RESULTS

The studies demonstrated the versatility of the framework and enabled exploration of the sensitivity to different settings, coupling modalities and geometries. As expected, changes in the DM, RP and coupling schemes illustrated a variation in RS over time, in turn affecting the ABM response. For example, combined small DM - fast RP led to similar ISR degrees as high DM - moderate RP (lumen area reduction of ∼13/17% vs. ∼30% without drug). The use of a patient-specific geometry with non-equally distributed struts resulted in a heterogeneous RS map, but did not remarkably impact the ABM response.

CONCLUSION

The application to a patient-specific geometry highlights the potential of the framework to address complex realistic scenarios and lays the foundations for future research, including calibration and validation on patient datasets and the investigation of the effects of different plaque composition on the arterial response to DES.

Far-Infrared Irradiation Decreases Proliferation in Basal and PDGF-Stimulated VSMCs Through AMPK-Mediated Inhibition of mTOR/p70S6K Signaling Axis

BACKGROUND

Far-infrared (FIR) irradiation has been reported to improve diverse cardiovascular diseases, including heart failure, hypertension, and atherosclerosis. The dysregulated proliferation of vascular smooth muscle cells (VSMCs) is well established to contribute to developing occlusive vascular diseases such as atherosclerosis and in-stent restenosis. However, the effects of FIR irradiation on VSMC proliferation and the underlying mechanism are unclear. This study investigated the molecular mechanism through which FIR irradiation inhibited VSMC proliferation.

METHODS

We performed cell proliferation and cell death assay, adenosine 5'-triphosphate (ATP) assay, inhibitor studies, transfection of dominant negative (dn)-AMP-activated protein kinase (AMPK) α1 gene, and western blot analyses. We also conducted confocal microscopic image analyses and ex vivo studies using isolated rat aortas.

RESULTS

FIR irradiation for 30 minutes decreased VSMC proliferation without altering the cell death. Furthermore, FIR irradiation accompanied decreases in phosphorylation of the mammalian target of rapamycin (mTOR) at Ser2448 (p-mTOR-Ser2448) and p70 S6 kinase (p70S6K) at Thr389 (p-p70S6K-Thr389). The phosphorylation of AMPK at Thr172 (p-AMPK-Thr172) was increased in FIR-irradiated VSMCs, which was accompanied by a decreased cellular ATP level. Similar to in vitro results, FIR irradiation increased p-AMPK-Thr172 and decreased p-mTOR-Ser2448 and p-p70S6K-Thr389 in isolated rat aortas. Pre-treatment with compound C, a specific AMPK inhibitor, or ectopic expression of dn-AMPKα1 gene, significantly reversed FIR irradiation-decreased VSMC proliferation, p-mTOR-Ser2448, and p-p70S6K-Thr389. On the other hand, hyperthermal stimulus (39°C) did not alter VSMC proliferation, cellular ATP level, and AMPK/mTOR/p70S6K phosphorylation. Finally, FIR irradiation attenuated platelet-derived growth factor (PDGF)-stimulated VSMC proliferation by increasing p-AMPK-Thr172, and decreasing p-mTOR-Ser2448 and p-p70S6K-Thr389 in PDGF-induced in vitro atherosclerosis model.

CONCLUSION

These results show that FIR irradiation decreases the basal and PDGF-stimulated VSMC proliferation, at least in part, by the AMPK-mediated inhibition of mTOR/p70S6K signaling axis irrespective of its hyperthermal effect. These observations suggest that FIR therapy can be used to treat arterial narrowing diseases, including atherosclerosis and in-stent restenosis.

Hif-1α/Slit2 Mediates Vascular Smooth Muscle Cell Phenotypic Changes in Restenosis of Bypass Grafts

Vascular smooth muscle cells (VSMCs) are involved in restenosis of bypass grafts and cause artery graft occlusion. This study aimed to explore the role of Slit2 in phenotypic switching of VSMCs and its effect on restenosis of vascular conduits. An animal model of vascular graft restenosis (VGR) was produced in SD rats and assessed by echocardiography. The expression of Slit2 and Hif-1α was measured in vivo and in vitro. After Slit2 overexpression, the migration and proliferation of VSMCs were detected in vitro, and the restenosis rates and phenotype of VSMCs were tested in vivo. The arteries of the VGR model presented significant stenosis, and Slit2 was decreased in VSMCs of the VGR model. In vitro, Slit2 overexpression inhibited the migration and proliferation of VSMCs, but Slit2 knockdown promoted migration and proliferation. Hypoxia induced Hif-1α but reduced Slit2, and Hif-1α negatively regulated Slit2 expression. Moreover, Slit2 overexpression weakened the rate of VGR and maintained the patency of artery bypass grafts, which suppressed the phenotypic switching of VSMCs. Slit2 inhibited the synthetic phenotype transformation to inhibit the migration and proliferation of VSMCs and delayed the VGR via Hif-1α.

Comparison of carotid endarterectomy and repeated carotid angioplasty and stenting for in-stent restenosis (CERCAS trial): a randomised study

BACKGROUND AND AIM

In-stent restenosis (ISR) belongs to an infrequent but potentially serious complication after carotid angioplasty and stenting in patients with severe carotid stenosis. Some of these patients might be contraindicated to repeat percutaneous transluminal angioplasty with or without stenting (rePTA/S). The purpose of the study is to compare the safety and effectiveness of carotid endarterectomy with stent removal (CEASR) and rePTA/S in patients with carotid ISR.

METHODS

Consecutive patients with carotid ISR (≥80%) were randomly allocated to the CEASR or rePTA/S group. The incidence of restenosis after intervention, stroke, transient ischaemic attack myocardial infarction and death 30 days and 1 year after intervention and restenosis 1 year after intervention between patients in CEASR and rePTA/S groups were statistically evaluated.

RESULTS

A total of 31 patients were included in the study; 14 patients (9 males; mean age 66.3±6.6 years) were allocated to CEASR and 17 patients (10 males; mean age 68.8±5.6 years) to the rePTA/S group. The implanted stent in carotid restenosis was successfully removed in all patients in the CEASR group. No clinical vascular event was recorded periproceduraly, 30 days and 1 year after intervention in both groups. Only one patient in the CEASR group had asymptomatic occlusion of the intervened carotid artery within 30 days and one patient died in the rePTA/S group within 1 year after intervention. Restenosis after intervention was significantly greater in the rePTA/S group (mean 20.9%) than in the CEASR group (mean 0%, p=0.04), but all stenoses were <50%. Incidence of 1-year restenosis that was ≥70% did not differ between the rePTA/S and CEASR groups (4 vs 1 patient; p=0.233).

CONCLUSION

CEASR seems to be effective and save procedures for patients with carotid ISR and might be considered as a treatment option.

TRIAL REGISTRATION NUMBER

NCT05390983.

Investigating the relationship between the VNTR variant of the interleukin-1 receptor antagonist gene and coronary in-stent restenosis

OBJECTIVE

This study aimed to examine the association between the interleukin-1 receptor antagonist gene (IL-1RN) and coronary in-stent restenosis (ISR) through the analysis of the VNTR variant based on the previously reported results.

MATERIALS AND METHODS

The samples were classified into two clearly defined groups: the case group, which comprised 45 patients diagnosed with in-stent restenosis (ISR+), and the control group, which included 60 patients without ISR (ISR-). Polymerase chain reaction (PCR) was performed to examine the 86-bp VNTR variant of the IL-1RN gene.

RESULTS

In the analysis of six identified groups consisting of variant alleles of 86 base pairs of VNTR of the IL-1RN gene statistically significant difference was observed for the presence of IL1RN*2 allele between cases and controls (p = 0.04, OR; 0.045).

CONCLUSION

Individuals with allele 2 of the IL-1Ra gene may be more predisposed to ISR. This could be due to an imbalance between IL-1Ra and IL-1β which is crucial in preventing the initiation or advancement of inflammatory diseases in specific organs. The observed phenomenon can be characterized by increased production of IL-1β and potential reduction of IL-1Ra as a result of functional VNTR variation in IL-RN gene.

Superficial Femoral Artery in-Stent Restenosis Treated with Paclitaxel-Coated Balloon Angioplasty - Results of Three-Year Follow-Up

BACKGROUND

In-stent restenosis remains a common and important complication after endovascular treatment of superficial femoral artery peripheral artery disease. It occurs in 14 to 35% of cases in 1 year and there is still no efficient treatment for this condition. Paclitaxel-coated balloons have shown promising results.

OBJECTIVE

Investigate the 3 year results of superficial femoral artery in-stent restenosis treated with paclitaxel-coated balloon angioplasty, using the Lutonix™ 035 device.

METHODS

We conducted a retrospective observational study with patients with symptomatic (Rutherford 2 to 5) superficial femoral artery in-stent restenosis, that were treated with paclitaxel-coated balloon angioplasty using the Lutonix™ 035 device, in a single center from January 2016 to December 2020. Duplex scan was used to follow the patients. Primary patency was obtained through Kaplan-Meier analysis. Mortality, and amputation rates were also evaluated.

RESULTS

105 patients were included. Two patients had technical failure and required an additional stent, and were thus excluded. 103 patients were analyzed. Primary patency was 91.26, 80.47, and 67.71%, respectively, in the first, second, and third year after the procedure. There were no deaths 30 days after the procedure. There were no major amputations during the 3 year follow-up.

CONCLUSION

Paclitaxel-coated balloon angioplasty with the Lutonix™ 035 device was a safe and effective treatment to superficial femoral artery in-stent restenoses. The results were maintained along the 3 year follow-up.

Complications and long-term in-stent restenosis of endovascular treatment of severe symptomatic intracranial atherosclerotic stenosis and relevant risk factors

To investigate the complications and in-stent restenosis of endovascular treatment of severe symptomatic intracranial atherosclerotic stenosis and relevant risk factors. Three hundred and fifty-four consecutive patients with intracranial atherosclerotic stenosis (70%-99%) were retrospectively enrolled. The clinical data, treatment outcomes, complications and in-stent restenosis at follow-up were analyzed. The endovascular treatment was composed of balloon dilatation only in 21 (5.93%) patients, and deployment of self-expandable stents in 232 (65.54%), balloon-expandable stents in 75 (21.19%), and both balloon- and self-expandable stents in 26 (7.34%), with a total of 359 stents being successfully deployed at the stenotic location. After treatment, the residual stenosis ranged 9.2%±1.5% (range 7%-19%), which was significantly (P < .05) smaller than that before treatment. Periprocedural complications occurred in 43 patients with a complication rate of 12.15% including arterial dissection in 4 (1.13%) patients, new cerebral infarction in 21 (5.93%), cerebral hemorrhage in 12 (3.3%), and subarachnoid hemorrhage in 6 (1.69%). Hyperlipidemia [odds ratio (OR) 10.35, 95% confidence interval (CI) 4.42-24.28, and P < .0001] and location at the middle cerebral artery (MCA) (OR 4.15, 95% CI 1.92-8.97, and P < .001) were significant (P < .05) risk factors for periprocedural complications, whereas hyperlipidemia (OR 11.28, 95% CI 4.65-30.60, and P < .0001), location at the MCA (or 5.26, 95% CI 2.03-15.08, and P < .001), and angulation (OR 1.02, 95% CI 1.00-1.04, and P = .02) were significant (P < .05) independent risk factors for periprocedural complications. Follow-up was performed in 287 (81.07%) patients at 6 to 36 (28 ± 6.7) months. In-stent restenosis was present in 36 (12.54%), and female sex (OR 2.53, and 95% CI 1.27-5.06) and periprocedural complications (OR 9.18, and 95% CI 3.52-23.96) were significant (P < .05) risk factors for in-stent restenosis, with periprocedural complication (OR 9.61, and 95% CI 3.48-27.23) as the only significant (P < .0001) independent risk factor for in-stent restenosis. A certain rate of periprocedural complications and in-stent stenosis may occur in endovascular treatment of severe intracranial stenosis, and the relevant risk factors may include hyperlipidemia, MCA location, angulation at the stenosis and female sex.

Paclitaxel drug-coated balloon-only angioplasty for de novo coronary artery disease in elective clinical practice

OBJECTIVE

We aimed to investigate the safety of drug-coated balloon (DCB)-only angioplasty compared to drug-eluting stent (DES), as part of routine clinical practice.

BACKGROUND

The recent BASKETSMALL2 trial demonstrated the safety and efficacy of DCB angioplasty for de novo small vessel disease. Registry data have also demonstrated that DCB angioplasty is safe; however, most of these studies are limited due to long recruitment time and a small number of patients with DCB compared to DES. Therefore, it is unclear if DCB-only strategy is safe to incorporate in routine elective clinical practice.

METHODS

We compared all-cause mortality and major cardiovascular endpoints (MACE), including unplanned target lesion revascularisation (TLR) of all patients treated with DCB or DES for first presentation of stable angina due to de novo coronary artery disease between 1st January 2015 and 15th November 2019. Data were analysed with Cox regression models and cumulative hazard plots.

RESULTS

We present 1237 patients; 544 treated with DCB and 693 treated with DES for de novo, mainly large-vessel coronary artery disease. On multivariable Cox regression analysis, only age and frailty remained significant adverse predictors of all-cause mortality. Univariable, cumulative hazard plots showed no difference between DCB and DES for either all-cause mortality or any of the major cardiovascular endpoints, including unplanned TLR. The results remained unchanged following propensity score-matched analysis.

CONCLUSION

DCB-only angioplasty, for stable angina and predominantly large vessels, is safe compared to DES as part of routine clinical practice, in terms of all-cause mortality and MACE, including unplanned TLR.

Smooth muscle differentiation of coronary intima in autopsy tissues after sirolimus-eluting stent implantation

BACKGROUND

In coronary atherosclerotic disease, the proliferation of intimal smooth muscle cells (SMCs) is regarded as beneficial with respect to stable and unstable plaques, but is thought detrimental in discussions on coronary stent restenosis. To resolve this discrepancy, we focused on the quality, not quantity, of intimal SMCs in coronary atherosclerotic disease.

METHODS

Autopsied coronary artery specimens from seven patients implanted with bare metal stents (BMS), three with paclitaxel-eluting stents (PES), and 10 with sirolimus (rapamycin)-eluting stents (SES) were immunostained for SMC markers. Cultured human coronary artery SMCs were also treated with sirolimus and paclitaxel.

RESULTS

Intimal SMC differentiation, estimated by the ratio of h-caldesmon+ cells to α-smooth muscle actin+ (α-SMA+) cells, was significantly increased whereas dedifferentiation, estimated from the ratio of fibroblast activation protein alpha (FAPα)+ cells to α-SMA+ cells, was significantly decreased, in tissues of SES compared with BMS cases. No difference in the degree of differentiation was found between PES and BMS cases or between the three groups in nonstented arteries used as controls. Correlation analyses for each field of view revealed a significant positive correlation between h-caldesmon and calponin staining but significant negative correlations with FAPα staining in α-SMA+ cells. Cultured SMCs were shorter (dedifferentiated) and showed an increased FAPα/α-SMA protein when treated with paclitaxel, whereas they became elongated (differentiated) and showed increased calponin/α-SMA proteins with sirolimus.

CONCLUSIONS

The SMCs of the coronary intima may differentiate after SES implantation. SMC differentiation may explain both the plaque stabilization and reduced risk of reintervention associated with SES.

Safety and efficacy of enterprise stenting for symptomatic atherosclerotic severe posterior circulation stenosis

PURPOSE

To investigate the safety and efficacy of Enterprise stent angioplasty and risk factors for the prognoses in treating symptomatic severe posterior circulation atherosclerotic stenosis (SSPCAS).

MATERIALS AND METHODS

Patients with SSPCAS who were treated with the Enterprise stent angioplasty were retrospectively enrolled. The clinical data, peri-procedural complications, postoperative residual stenosis, in-stent restenosis and recurrent stroke at follow-up were analyzed.

RESULTS

262 patients with 275 stenotic lesions treated with the Enterprise stent angioplasty were enrolled. The stenosis degree was reduced from 86.3 ± 6.2% before to 19.3 ± 5.4% after stenting. Complications occurred in 14 (5.3%) patients. Clinical follow-up was performed in 245 (93.51%) patients for 16.5 ± 7.3 months. During 1 year follow-up, 7 patients (2.9%) had recurrent symptoms, including 4 patients with stenting in the intracranial vertebral artery and 3 in the basilar artery. Imaging follow-up was conducted in 223 (85.11%) patients. In-stent restenosis was present in 35 patients (15.7%), with the restenosis rate of 26.4% (n = 23) in the intracranial vertebral artery, which was significantly (P < 0.001) greater than in the basilar artery (8.8%). Six patients (17.1%) with in-stent restenosis were symptomatic. The stenotic length was the only significant (P = 0.026 and 0.024, respectively) independent risk factor for 1 year stroke or death events and in-stent restenosis.

CONCLUSION

The Enterprise stent can be safely and efficaciously applied in the treatment of symptomatic severe posterior circulation atherosclerotic stenosis, with a relatively low rate of in-stent restenosis and recurrent stroke within 1 year. The stenotic length was the only significant independent risk factor for 1 year stroke or death events and in-stent restenosis.

Angioscopic and histopathological findings of in-stent restenosis in external iliac artery

Little has been reported on the angioscopic and histopathological findings of in-stent restenosis (ISR) in the iliac artery. Here, we report a case of a male patient in his 70s who showed recurrent ISR in the right external iliac artery. We observed the ISR lesions with not only an intravascular ultrasound (IVUS) but also an angioscopy and a biopsy to clarify the mechanism of ISR. These imaging and histopathological findings showed neointimal hyperplasia, and we performed endovascular therapy with covered stent placement to prevent neointimal formation. Not only the IVUS but also the angioscopic and histopathological findings were helpful to clarify the mechanism of ISR and to determine the treatment plan.

Image-guided intravascular brachytherapy dose escalation

PURPOSE

Coronary stents reduce IVBT radiation dose with a single layer by 10-30%. However, the impact of multiple stent layers and stent expansion remains unexplored. Individualized dose adjustments considering variations in stent layers and expansion could improve radiation delivery effectiveness.

METHODS

EGSnrc was used to compute the delivered vessel wall dose in various IVBT scenarios. Stent effects were modeled for the stent density of 25%, 50%, and 75% with 1, 2, and 3 layers respectively. Doses were calculated at 1.75 to 5.00 mm away from the source center, normalized to 100% at 2 mm.

RESULTS

Dose fall-off increased with increasing stent density. With a single layer, the dose at 2 mm from source fell from 100% of prescription to 92%, 83% and 73% at 25%, 50% and 75% density, respectively. The computed dose to points with increasing radial distance from the source decreased progressively with increasing stent layers. With three layers, at 75% stent density, the dose at 2 mm from source center fell to 38%.

CONCLUSIONS

A schema for image-guided IVBT dose adjustment is described. While it would be an improvement over current standard of care, myriad factors remain to be addressed in a comprehensive effort to optimize IVBT.

Predicting 1-year in-stent restenosis in superficial femoral arteries through multiscale computational modelling

In-stent restenosis in superficial femoral arteries (SFAs) is a complex, multi-factorial and multiscale vascular adaptation process whose thorough understanding is still lacking. Multiscale computational agent-based modelling has recently emerged as a promising approach to decipher mechanobiological mechanisms driving the arterial response to the endovascular intervention. However, the long-term arterial response has never been investigated with this approach, although being of fundamental relevance. In this context, this study investigates the 1-year post-operative arterial wall remodelling in three patient-specific stented SFA lesions through a fully coupled multiscale agent-based modelling framework. The framework integrates the effects of local haemodynamics and monocyte gene expression data on cellular dynamics through a bi-directional coupling of computational fluid dynamics simulations with an agent-based model of cellular activities. The framework was calibrated on the follow-up data at 1 month and 6 months of one stented SFA lesion and then applied to the other two lesions. The calibrated framework successfully captured (i) the high lumen area reduction occurring within the first post-operative month and (ii) the stabilization of the median lumen area from 1-month to 1-year follow-ups in all the stented lesions, demonstrating the potentialities of the proposed approach for investigating patient-specific short- and long-term responses to endovascular interventions.

Perturbed post-translational modification (PTM) network atlas of collagen I during stent-induced neointima formation

Myocardial infarction (MI) leading to heart failure contributes to almost 85% of deaths associated with CVDs. MI results from plaque formation in the coronary artery which leads to a lack of oxygen and nutrients in the myocardium. To date, stenting is a widely used gold-standard technique to maintain the proper blood flow through coronary circulation in the myocardium. Bare metal stents (BMS) and drug-eluting stents (DES) are majorly used in implantation. However, BMS and DES both can induce neointima formation by depositing excessive collagens in the coronary arteries leading to restenosis. Identification and quantitative analysis of site-specific post-translational modifications (PTMs) of deposited COL1A1 from neointima ECM are not known. Applying our in-house workflow, we re-analyzed a previously published mass-spectrometry data set to comprehensively map site-specific prolyl-hydroxylation, lysyl hydroxylation, and O-glycosylation sites in COL1A1 from neointima ECM. Furthermore, we quantitated the occupancy level of 9 3-hydroxyproline (3-HyP) sites, 2 hydroxylysine sites, and glycosylation microheterogeneity on 6 lysine sites of COL1A1. Although the total level of COL1A1 was decreased in DES-induced neointima, the occupancy levels of 2 3-HyP sites (P⁸⁷², and P⁸⁸¹) and 2 HyK (K⁴³⁵ and K⁷⁶⁸) sites of COL1A1 were significantly (p < 0.05) elevated in DES-induced neointima compared to BMS-induced neointima. We also found O-glycosylation to be significantly elevated on 3 lysine sites (K⁵⁷³, K³³⁹, and K and K⁸⁴⁹) of COL1A1 in DES-induced neointima compared to BMS-induced neointima. Taken together, our first comprehensive PTM analysis of COL1A1 reflected significant site-specific alterations that may play a very important role in the ECM remodeling during stent-induced neointima formation in MI patients. SIGNIFICANCE: The knowledge about site-specific post-translational modifications (PTMs) of collagen 1 deposited in the neointima ECM during the post-stenting restenosis process is absent. Here for the first time, we report the altered levels of COL1A1 PTMs during metal stent and drug-eluting stent-induced neointima formation. Our study showcases a novel ECM remodeling through site-specific collagen PTMs during stent-induced restenosis.

The Effects of Sirolimus and Magnesium on Primary Human Coronary Endothelial Cells: An In Vitro Study

Drug eluting magnesium (Mg) bioresorbable scaffolds represent a novel paradigm in percutaneous coronary intervention because Mg-based alloys are biocompatible, have adequate mechanical properties and can be resorbed without adverse events. Importantly, Mg is fundamental in many biological processes, mitigates the inflammatory response and is beneficial for the endothelium. Sirolimus is widely used as an antiproliferative agent in drug eluting stents to inhibit the proliferation of smooth muscle cells, thus reducing the occurrence of stent restenosis. Little is known about the potential interplay between sirolimus and Mg in cultured human coronary artery endothelial cells (hCAEC). Therefore, the cells were treated with sirolimus in the presence of different concentrations of extracellular Mg. Cell viability, migration, barrier function, adhesivity and nitric oxide synthesis were assessed. Sirolimus impairs the viability of subconfluent, but not of confluent cells independently from the concentration of Mg in the culture medium. In confluent cells, sirolimus inhibits migration, while it cooperates with Mg in exerting an anti-inflammatory action that might have a role in preventing restenosis and thrombosis.

Design of the FP-RESTORE study: a protocol for prospective, observational study of real-world treatments with endovascular therapy in patients with femoropopliteal artery Tosaka III in-stent restenosis

INTRODUCTION

Femoropopliteal artery in-stent restenosis (FP-ISR) represents one of the main obstacles for stent implantation in peripheral artery disease patients, especially Tosaka III FP-ISR, which is also referred to as in-stent occlusion. Diverse endovascular treatments of Tosaka III FP-ISR are available, and the results are unequivocal. However, real-world data are limited. This study aims to evaluate the efficacy, safety and health economics evaluation of various endovascular procedures in the treatment of Tosaka III FP-ISR.

METHOD AND ANALYSIS

This study is a prospective, multicentre, real-world, observational clinical study. Patients diagnosed with Tosaka III FP-ISR and treated with endovascular procedures in nine centres from 1 April 2021 to 31 December 2022 will be recruited. The relevant clinical information, Ankle-Brachial Index and CT angiography will be collected. All the participants will undergo follow-up at 1, 6, 12, 18 and 24 months after the operation. The primary outcome is freedom from clinically driven target lesion revascularisation at 24 months. Safety and health economics issues will also be reported.

ETHICS AND DISSEMINATION

The FP-RESTORE clinical trial has been registered at ClinicalTrials.gov (http://clinicaltrials.gov/). This study was also approved by the Institutional Review Board and Human Research Ethics Committee of Zhongshan Hospital, Fudan University (approval number: B2021-427). Moreover, written informed consent will be obtained at the time of recruitment. The study outcomes will be disseminated by publication in a peer-reviewed journal to provide information for further clinical practice.

TRIAL REGISTRATION NUMBER

NCT04801004.

Increased cholesterol absorption is associated with In-stent-restenosis after stent implantation for stable coronary artery disease

BACKGROUND AND AIMS

Blood cholesterol levels are regulated by competing mechanisms of cholesterol synthesis, absorption and excretion. Plant sterols are natural constituents of plants, are not synthesized in humans, and serve as markers for cholesterol absorption. Ezetimibe lowers the intestinal absorption of cholesterol and plant sterols. We analyzed the associations of differences in cholesterol metabolism, in particular increased cholesterol absorption, and the occurrence of in-stent restenosis (ISR) in patients with stable coronary artery disease.

METHODS

Elective stent implantation of de novo stenosis was conducted in 59 patients (74.6 % males, 67.2 ± 9.6 years). Cholesterol and non-cholesterol sterols were quantified in serum samples by gas chromatography or mass spectrometry. ISR was assessed by optical coherence tomography (OCT) and quantitative angiography (QCA) after six months.

RESULTS

Markers for cholesterol absorption (e.g. campesterol-to-cholesterol) were positively associated with ISR measured by QCA (%diameter stenosis, late lumen loss) and OCT (proliferation volume, %area stenosis), whereas markers for cholesterol synthesis (e.g. lathosterol-to-cholesterol) were negatively associated with ISR (%area stenosis: r = -0.271, p = 0.043). There was no association between ISR and total cholesterol, LDL, HDL, triglycerides. Markers for cholesterol absorption (e.g. campesterol-to-cholesterol) were significantly lower in ezetimibe-treated patients compared to patients on a statin only (1.29 ± 0.69 vs. 2.22 ± 1.23; p = 0.007). Combined lipid-lowering with ezetimibe plus statin reduced ISR compared to statin only (13.7 ± 10.4 vs. 22.5 ± 12.1 %diameter stenosis, p = 0.015).

CONCLUSIONS

Differences in cholesterol metabolism, more specifically increased cholesterol absorption, are associated with ISR.

Hemodynamic and Geometric Risk Factors for In-Stent Restenosis in Patients with Intracranial Atherosclerotic Stenosis

Methods

Severe ICAS patients managed with percutaneous transluminal angioplasty and stenting (PTAS) were included in the retrospective cohort study and were divided into two groups according to whether ISR occurred at follow-up (ISR group and no-ISR group). Computational fluid dynamics models were built based on digital subtraction angiography before and after PTAS to simulate blood flow and quantify hemodynamic parameters. The associations between vessel geometry, hemodynamics, and ISR in ICAS patients were investigated.

Results

Among 39 patients, ISR occurred in seven patients (17.95%) after a mean follow-up period of 6.69 ± 3.24 months. Stenting decreased vessel angulation (51.11° [40.07°-67.27°] vs. 15.97° [0.00°-36.16°], P = 0.000) and vessel tortuosity (0.09 [0.06-0.13] vs. 0.01 [0.00-0.03], P = 0.000). Meanwhile, the translational pressure ratio (PR) dramatically increased (0.07 [0.00-0.31] vs. 0.62 [0.41-0.82], P = 0.000) with the wall shear stress ratio decreased (13.93 [8.37-40.30] vs. 2.90 [1.69-4.48], P = 0.000). In the multivariate analysis, smaller Δ tortuosity (P = 0.038) was independently associated with the occurrence of ISR, and smaller post-PTAS translesional PR was also a predictive factor of marginal significance (P = 0.059).

Conclusion

PTAS decreased vessel angulation, vessel tortuosity, and translesional wall shear stress ratio while it increased translesional pressure ratio (PR) dramatically in ICAS patients. Smaller Δ tortuosity was found to be a risk factor for ISR, and smaller post-PTAS translesional PR was also a predictive factor of marginal significance, indicating that both geometric and hemodynamic parameters played important roles in the occurrence of ISR after PTAS.

Association between Oxidative Burden and Restenosis: A Case-Control Study

Background

In-stent restenosis (ISR) is an important clinical complication that occurs following stent implantation. The application of drug-eluting stents (DES) and even consumption of drugs such as antiplatelet agents and statins are not completely effective in reducing ISR risk. Since the number of these patients continues to rise, it is pivotal to detect patients who are at a higher risk of ISR. In addition, identification of biochemical markers of ISR could give the right perspective on choosing the proper strategy to treat these patients. Several pathophysiological pathways including oxidative stress (OS) are implicated in the progression of ISR. Hence, this study aimed to evaluate the association between oxidative/anti-oxidative markers and ISR.

Methods

This was a case-control study which comprised 21 ISR, 26 NISR (non-ISR), and 20 healthy subjects. The serum levels of OS markers including malondialdehyde (MDA), thiol groups (GSH), total antioxidant capacity (TAC), and the activity of serum antioxidant enzymes such as glutathione peroxidase (GPx) and superoxide dismutase (SOD) were assessed by colorimetric methods. The overall oxidative burden was assessed using a pro-oxidant-antioxidant balance (PAB) assay.

Results

MDA levels were considerably higher in the ISR group when compared to healthy subjects (P = 0.004). PAB also indicated significantly higher values in both ISR (P < 0.001) and NISR (P < 0.001) groups related to healthy subjects. No significant differences were observed between the studied groups regarding thiol levels, antioxidant enzyme activities, and TAC. Multinomial logistic regression analysis showed that elevated serum levels of MDA (OR: 1.028, 95% CI: 1.008-1.048; P = 0.006) and PAB (OR: 1.076, 95% CI: 1.017-1.139; P = 0.011) were significantly associated with higher ISR risk; however, increased values of TAC (OR: 0.990, 95% CI: 0.982-0.999; P = 0.030) were significantly associated with decreased ISR risk, while after adjustment for confounders, only SOD activity (OR: 0.0, 95% CI: 0.0-0.0; P < 0.001) and PAB value (OR: 1.866, 95% CI: 1.856-1.900; P < 0.001) showed association with ISR risk.

Conclusion

According to the present findings, some oxidative and antioxidative markers like PAB and SOD activity showed the potential in the prediction of ISR risk.

Coronary stent infection: a systematic review

Coronary stent infection (CSI) is the rarest complication associated with the percutaneous coronary intervention, occurring in less than 0.1% of cases. So far, all reported instances are limited to case reports. CSI presents itself in various, often confusing, ways in clinical settings. Therefore, the current systematic review summarizes reports of CSI's clinical presentations, causative pathogens, diagnoses and treatments. This systematic review considered three online databases, using reference lists as an additional source. All case reports or case series with stent infection in the coronary artery were included - however, reviews or commentaries, articles not published in English, and articles mentioning a history of hemodialysis or any surgery were excluded. Thirty-two studies on 34 CSI patients were included in the final qualitative analysis. CSI predominantly affected males of a wide range of ages. The most common symptoms were chest pain and fever with various onsets. Interestingly, CSI usually occurred during the first stent implantation. Cultures and coronary angiography were the most common methods used to diagnose CSI. Furthermore, drug-eluting stents had a higher risk of infection than bare-metal stents. Aneurysms were the most frequent abnormalities observed in infected stents. The bacteria that most often caused CSI were Staphylococcus aureus and Pseudomonas aeroginosa. More than 90% of the reports mentioned using various antibiotics, and 74% mentioned carrying out surgery. Finally, a mortality rate of 26.47% among CSI patients was calculated.

Balloon-Assisted Angioplasty for the Treatment of In-Stent Restenosis After Vertebral Artery Ostium Stenting: Experiences From One Single Center

BACKGROUND

Stenting appears to be a safe means of treatment for vertebral artery ostium stenosis with low complication rates and positive long-term effects, but the incidence of in-stent restenosis (ISR) after stenting is high. Different treatment strategies are applied for the revascularization of ISR; however, currently the optional approach is not recommended. The study was designed to investigate the feasibility, safety, and effectiveness of balloon-assisted angioplasty for the treatment of ISR after vertebral artery ostium stenosis.

METHODS

In this study, we included patients from the Department of Neurology, Lishui Hospital of Zhejiang University, who were treated with balloon-assisted angioplasty as a result of suffering from ISR after previously undergoing vertebral artery ostium stenting. We retrospectively analyzed the clinical and functional outcomes of the patients.

RESULTS

From January 2015 to December 2019, 11 patients were included in the study. The technical success rate reached 100% and the average operation time was 73 minutes. The Thrombolysis in Cerebral Infarction Score 2b-3 was acquired in all patients except 1 patient, who was presented with symptoms of hypoperfusion syndrome. The remaining 10 patients did not experience any intraoperative or postoperative complications. No restenosis, new cerebral infarction or transient ischemic attack were reported within 6 months of follow-up.

CONCLUSION

Balloon-assisted angioplasty could be feasible for the treatment of ISR after vertebral artery ostium stenting, however, more research is needed to confirm this.

Value of contrast-enhanced ultrasound for diagnosis and follow-up of renal artery stenosis in patients with chronic kidney disease

OBJECTIVE

To evaluate whether contrast-enhanced ultrasound (CEUS) is an accurate, non-nephrotoxic diagnostic method and follow-up tool for use in patients with chronic kidney disease (CKD) and renal artery stenosis (RAS).

METHODS

In this prospective and monocentric study, we compared the sensitivity and specificity of CEUS for the diagnosis of RAS in CKD patients, using digital subtraction angiography (DSA) or computed tomographic angiography (CTA) as the gold standard methods. Further, the value of CEUS for distinguishing restenosis from other diseases was assessed. The ultrasound physicians conducted the examinations and served as the CEUS report readers who were blinded to the DSA or CTA results.

RESULTS

Patients with RAS (n = 60) were enrolled. Average patient age was 64.4 ± 18.0 years and median estimated glomerular filtration rate was 66.1 mL/min/1.73 m². CEUS was used to image 94 stenotic renal arteries and DSA- or CTA-verified stenosis was present in 96 renal arteries. The kappa value for CEUS was 0.776 (P < 0.001), with an accuracy of 92.5%, a sensitivity of 94.7%, and a specificity of 84.0%. The accuracy of CEUS was the same for the diagnosis of the CKD3b-5 group as for the CKD1-3a group (100% vs. 87.5%, P = 0.148). There was no difference in CEUS accuracy for the diagnosis of Takayasu RAS compared with atherosclerotic RAS (95.8% vs. 91.7%, P = 0.795). Twenty-nine CEUS examinations were performed to follow in-stent restenosis or progression of RAS, with a median follow-up time of 5.0 months (range 1.0-20.0). Two cases of in-stent restenosis in patients suffering from deteriorating kidney function and recurrent hypertension were examined by CEUS.

CONCLUSION

CEUS examination is a credible alternative for diagnosing moderate and severe RAS in patients with CKD, and is a reliable tool for follow-up surveillance after renal artery revascularization treatment. It shouldn't be thought as a color-coded duplex ultrasonography rescue in these patients.

Predictive Value of Perioperative Cytokine Levels on the Risk for In-Stent Restenosis in Acute Myocardial Infarction Patients

To investigate the value of perioperative cytokine levels in predicting the risk for in-stent restenosis in patients with acute myocardial infarction. 452 patients with acute myocardial infarction admitted to our hospital between June 2018 and June 2020 were prospectively selected as subjects. All patients underwent percutaneous coronary intervention. The baseline data of the patients were collected. Venous blood was taken before, 24 hours, and 3 days after the operation to detect the levels of related cytokines. Follow-up was performed for 1 year. The patients were assigned to restenosis and nonrestenosis groups according to the presence and absence of restenosis. Multivariate logistic analysis was used to explore the influencing factors of the risk for in-stent restenosis in patients with acute myocardial infarction. By July 1, 2021, 449 cases had been followed up. Of them, 44 cases suffered from in-stent restenosis and 405 cases did not affect in-stent restenosis. The incidence of in-stent restenosis was 9.80%. Before, 24 hours, and 3 days after the operation, the lipoprotein-associated phospholipase A2 (Lp-PLA2) level was significantly higher in the restenosis group than that in the nonrestenosis group. At 3 days after the operation, the interleukin 6 (IL-6) level was significantly higher in the restenosis group than that in the nonrestenosis group (P < 0.05). Multivariate logistic analysis displayed that Lp-PLA2 level preoperatively (OR = 1.048, 95% CI 1.029-1.068), Lp-PLA2 level 24 hours postoperatively (OR = 1.013, 95% CI 1.007-1.019), Lp-PLA2 level 3 days postoperatively (OR = 1.032, 95% CI 1.015-1.048), and IL-6 level 3 days postoperatively (OR = 1.020, 95% CI 1.000-1.040) were risk factors for in-stent restenosis (all P < 0.05). IL-6 and Lp-PLA2 levels can predict the risk for in-stent restenosis in patients with acute myocardial infarction in the perioperative period.

Rationale and design for comparison of non-compliant balloon with drug-coating balloon angioplasty for side branch after provisional stenting for patients with true coronary bifurcation lesions: a prospective, multicentre and randomised DCB-BIF trial

INTRODUCTION

Provisional stenting using drug-eluting stent is effective for simple coronary bifurcation lesions. Kissing balloon inflation using conventional non-compliant balloon is the primary treatment of side branch (SB) after main vessel (MV) stenting. Drug-coating balloon (DCB) is reported to be associated with less frequent clinical events in in-stent restenosis and small vessel disease. The importance of DCB in bifurcation treatment is understudied. Accordingly, this trial is designed to investigate the superiority of DCB to non-compliant balloon angioplasty for SB after provisional stenting in patients with true coronary bifurcation lesions.

METHODS AND ANALYSIS

The DCB-BIF trial is a prospective, multicentre, randomised, superiority trial including 784 patients with true coronary bifurcation lesions. Patients will be randomised in a 1:1 fashion to receive either DCB or non-compliant balloon angioplasty if SB diameter stenosis >70% after MV stenting. The primary endpoint is the composite of major adverse cardiac event at the 1-year follow-up, including cardiac death, myocardial infarction (MI) or clinically driven target lesion revascularisation. The major secondary endpoints include all-cause death, periprocedural MI, spontaneous MI, clinically driven target vessel revascularisation, in-stent restenosis, stroke and individual component of the primary endpoint. The safety endpoint is the risk of stent thrombosis.

ETHICS AND DISSEMINATION

The study protocol and informed consent have been reviewed and approved by the Institutional Review Board of all participating centres. The written informed consent for participation in the trial will be obtained from all participants. The results of this study will be published in a peer-reviewed journal and disseminated at conferences.

TRIAL REGISTRATION NUMBER

NCT04242134.

Unstable Angina Induced by Fracture of a Recently Implanted Drug-Eluting Stent

Stent fracture is a rather infrequent complication associated with in-stent restenosis, thrombosis, aneurysm formation, and ischemic events. Several stent-related parameters, such as the use of longer or multiple stents, stent overlapping, and balloon/stent overexpansion are potential predictors of stent fracture. Stents deployed in right coronary artery lesions with exaggerated motion, tortuosity, or severe calcification are also generally considered to be at higher risk for fracture. This case demonstrates that intravascular ultrasound imaging is extremely useful to confirm the diagnosis and identify the possible mechanism of the stent fracture, as well as to assess the final result after subsequent angioplasty.

[Efficacy of drug coated balloon versus conventional balloon in the treatment of coronary de novo bifurcation lesions: a meta-analysis]

Objective: To systematically evaluate the efficacy of drug coated balloon (DCB) versus conventional balloon in the treatment of coronary de novo bifurcation lesions. Methods: The databases of PubMed, Embase, Cochrane Library, Web of science, CNKI (China National Knowledge Infrastructure), Wanfang database, VIP, China Biology Medicine disc, Chinese clinical trial registry, American clinical trial registry and cardiovascular related websites until September 2020 were retrieved for collecting the randomized controlled trials (RCT) comparing DCB versus conventional balloon in the treatment of coronary de novo bifurcation lesions. The risk of bias of included studies was assessed using the Cochrane risk assessment tool. The meta-analysis was performed by using Revman 5.3 and Stata 14.0 software. Results: Seven RCTs with a total of 613 patients were included in this meta-analysis. Among the included studies, 4 articles reached the low risk of bias, and the other 3 articles reached the medium risk of bias. The results of meta-analysis showed that there was no significant difference in the major adverse cardiac events (RR=0.65, 95%CI 0.39-1.08, P=0.10), myocardial infarction (RR=0.68, 95%CI 0.25-1.80, P=0.43), target lesion revascularization (RR=0.94, 95%CI 0.53-1.67, P=0.83) between DCB group and conventional balloon group. Late lumen loss of side branch was less in the DCB group than that in the conventional balloon group (WMD=-0.25, 95%CI -0.41--0.09, P<0.01) and the risk of side branch restenosis was also lower in the DCB group than that in the conventional balloon group (RR=0.47, 95%CI 0.22-0.98, P<0.05). However, subgroup analysis showed that the conclusions of domestic studies and foreign studies on late lumen loss and side branch restenosis were inconsistent. The meta-analysis based on domestic literature showed that the risk of side branch restenosis after DCB treatment was lower compared with conventional balloon group (RR=0.29, 95%CI 0.15-0.57, P<0.05), while this parameter derived from foreign literatures remained unchanged between two groups (P=0.53). The meta-analysis results of domestic literature showed that late lumen loss in DCB group was less than that in conventional balloon group (WMD=-0.32, 95%CI -0.51--0.13, P<0.05), but this phenomenon was not observed in foreign literatures (P=0.30). Conclusions: The use of DCB in the treatment of coronary de novo bifurcation lesions has the potential to reduce the rate of restenosis and late lumen loss of side branch compared with conventional balloon group. However, due to the limitation on quantity, quality and results of published studies, more high-quality and large scale RCTs are still needed to confirm these findings.

Biomimetic, ROS-detonable nanoclusters - A multimodal nanoplatform for anti-restenotic therapy

The long-term success of endovascular intervention has long been overshadowed by vessel re-occlusion, also known as restenosis. Mainstream anti-restenotic devices, such as drug-eluting stent (DES) and drug-coated balloon (DCB), were recently shown with suboptimal performances and life-threatening complications, thereby underpinning the urgent need for alternative strategies with enhanced efficacy and safety profile. In our current study, we engineered a multimodal nanocluster formed by self-assembly of unimolecular nanoparticles and surface coated with platelet membrane, specifically tailored for precision drug delivery in endovascular applications. More specifically, it incorporates the combined merits of platelet membrane coating (lesion targetability and biocompatibility), reactive oxygen species (ROS)-detonable "cluster-bomb" chemistry (to trigger the large-to-small size transition at the target site, thereby achieving longer circulation time and higher tissue penetration), and sustained drug release. Using RVX-208 (an emerging anti-restenotic drug under clinical trials) as the model payload, we demonstrated the superior performances of our nanocluster over conventional poly(lactic-co-glycolic acid) (PLGA) nanoparticle. In cultured vascular smooth muscle cell (VSMC), the drug-loaded nanocluster induced effective inhibition of proliferation and protective gene expression (e.g., APOA-I) with a significantly reduced dosage of RVX-208 (1 μM). In a rat model of balloon angioplasty, intravenous injection of Cy5.5-tagged nanocluster led to greater lesion targetability, improved biodistribution, and deeper penetration into injured vessel walls featuring enriched ROS. Moreover, in contrast to either free drug solution or drug-loaded PLGA nanoparticle formulation, a single injection with the drug-loaded nanocluster (10 mg/kg of RVX-208) was sufficient to substantially mitigate restenosis. Additionally, this nanocluster also demonstrated biocompatibility according to in vitro cytotoxicity assay and in vivo histological and tissue qPCR analysis. Overall, our multimodal nanocluster offers improved targetability, tissue penetration, and ROS-responsive release over conventional nanoparticles, therefore making it a highly promising platform for development of next-generation endovascular therapies.

A prediction model based on platelet parameters, lipid levels, and angiographic characteristics to predict in-stent restenosis in coronary artery disease patients implanted with drug-eluting stents

BACKGROUND

The present study was aimed to establish a prediction model for in-stent restenosis (ISR) in subjects who had undergone percutaneous coronary intervention (PCI) with drug-eluting stents (DESs).

MATERIALS AND METHODS

A retrospective cohort study was conducted. From September 2010 to September 2013, we included 968 subjects who had received coronary follow-up angiography after primary PCI. The logistic regression analysis, receiver operator characteristic (ROC) analysis, nomogram analysis, Hosmer-Lemeshow χ2 statistic, and calibration curve were applied to build and evaluate the prediction model.

RESULTS

Fifty-six patients (5.79%) occurred ISR. The platelet distribution width (PDW), total cholesterol (TC), systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDL-C), and lesion vessels had significant differences between ISR and non-ISR groups (all P < 0.05). And these variables were independently associated with ISR (all P < 0.05). Furthermore, they were identified as predictors (all AUC > 0.5 and P < 0.05) to establish a prediction model. The prediction model showed a good value of area under curve (AUC) (95%CI): 0.72 (0.64-0.80), and its optimized cut-off was 6.39 with 71% sensitivity and 65% specificity to predict ISR.

CONCLUSION

The incidence of ISR is 5.79% in CAD patients with DES implantation in the Xinjiang population, China. The prediction model based on PDW, SBP, TC, LDL-C, and lesion vessels was an effective model to predict ISR in CAD patients with DESs implantation.

Healed Erosion: The Role of Pre-interventional Optical Coherence Tomography in a Patient Clinically Suspected of Having Unstable Angina with Coronary Spasm

A 46-year-old man complained of chest pain at rest for the past three months. His symptoms gradually exacerbated and were suspected of being due to unstable angina. A coronary angiogram revealed focal tight stenosis at the proximal left anterior descending coronary artery with gross spastic coronary findings. Optical coherence tomography (OCT) revealed layered low-intensity structures with microvessels and the accumulation of macrophages, which indicated progressive stenosis with multiple-layered organized thrombus caused by coronary erosion. We treated the stenosis using a drug-coated balloon instead of drug-eluting stents. There was no restenosis, and OCT revealed good plaque healing at follow-up. This case suggests that the pre-interventional OCT plaque morphology can have a positive impact on the revascularization strategy.