Restenosis, Stent Thrombosis, and Bleeding Complications: Navigating Between Scylla and Charybdis

Impact of the stent footprint on endothelial wall shear stress in patient-specific coronary arteries: A computational analysis from the SHEAR-STENT trial

BACKGROUND AND OBJECTIVE

Wall shear stress (WSS) has been known to play a critical role in the development of several complications following coronary artery stenting, including in-stent restenosis and thrombosis. Computational fluid dynamics is often used to quantify the post-stenting WSS, which may potentially be used as a predictive metric. However, large-scale studies for WSS-based risk stratification often neglect the footprint of the stent due to reconstruction challenges. The primary objective of this study is to statistically evaluate the impact of the stent footprints (Xience and Resolute stents) on the computed endothelial WSS and quantitatively identify the relationship between these local hemodynamic alterations and the global properties of the vessel, such as curvature, on WSS. The ultimate goal is to evaluate whether and when it is worth including the footprint of the stent in an in-silico study to compute the WSS reliably.

METHODS

A previously developed semi-automated reconstruction approach for patient-specific coronaries was employed as a part of the SHEAR-STENT trial. A subset of patients was analyzed (N=30), and CFD simulations were performed with and without the stent to evaluate the impact of the stent footprint on WSS. Due to the computationally expensive nature of transient analyses, a sub-cohort of ten patients were used to assess the reliability of WSS obtained from steady computations as a surrogate for the time-averaged results. Global and local vessel curvature data were extracted for all cases and evaluated against stent-induced alterations in the WSS. The differences between the Xience and Resolute stent platforms were also examined to quantify each stent's unique WSS footprint.

RESULTS

Results from the surrogate analysis indicate that steady WSS serves as an excellent approximation of the time-averaged computations. The presence of either stent footprint causes a statistically significant decrease in the space-averaged WSS, and a significant increase in the endothelial regions exposed to very low WSS as well (<0.5 Pa). Negative correlations were observed between vessel curvature and WSS differences, indicating that macroscopic vessel characteristics play a more prominent role in determining endothelial WSS at higher curvature values. In our pool of cases, comparison of Xience and Resolute stents revealed that the Resolute platform seems to lead to lower space-averaged WSS and an increase in areas of very low WSS.

CONCLUSION

These results outline (1) the necessity of including the stent footprint for accurate in-silico WSS analysis; (2) the global features of stented arteries serving as the dominant determinant of WSS past a certain curvature threshold; and (3) the Xience stent resulting in a milder presence of hemodynamically unfavorable WSS regions compared to the Resolute stent.

Evaluation of the effectiveness and safety of preoperative drug elution balloon therapy in patients with elective tumor surgery and coronary heart disease: a retrospective clinical study : The best choice of PCI for patients with elective tumor surgery and CHD

BACKGROUND

The selection of percutaneous coronary intervention (PCI) regimen for patients undergoing elective tumor surgery with coronary heart disease(CHD) remains controversial.To evaluate the effectiveness and safety of using Drug Eluting Balloons (DEB) in study patients.

METHODS

A retrospective study was conducted on 127 patients undergoing elective tumor surgery with CHD who received preoperative PCI treatment at the Fourth Hospital of Hebei Medical University from January 2022 to May 2023. According to the PCI treatment plan, it is divided into Drug Eluting Balloons (DEB) group (n = 61) and Drug Eluting Stents (DES) group (n = 66). The primary endpoints of follow-up were all-cause mortality and major adverse cardiac events (MACE), while the secondary endpoints were bleeding and Venous thrombotic events. Compare the incidence of all-cause mortality events, MACE, bleeding and Venous thrombotic events between two groups of patients during the perioperative period and 1-year after the surgery.

RESULTS

During perioperative period, no all-cause death occurred in both groups. MACE in DEB group was lower than that in DES group (9.8%VS.27.3%, P = 0.012). For Confirmed the overall treatment time and Interventional-surgical time, DEB group was shorter than DES group(108[60,155]VS.218[170, 320],P< 0.001),(80[45.5,120]VS.210[168,300], P< 0.001). During the follow-up period, there were all-cause mortality (3.3%VS.13.6%, P = 0.038), MACE (9.8%VS.24.2%, P = 0.032)in the DEB and DES groups.

CONCLUSIONS

The results of this retrospective study showed that the all-cause mortality and MACE in patients were significantly lower than those in the DES group. DEB can also shorten the Interventional-surgical time, thus greatly reducing the overall treatment time.

Interleukin-1 Blockade in Patients With ST-Segment Elevation Myocardial Infarction Across the Spectrum of Coronary Artery Disease Complexity

ABSTRACT

Patients with ST-segment elevation myocardial infarction (STEMI) and complex coronary artery disease (CAD) face a poor prognosis, including increased heart failure (HF) risk. Phase 2 clinical trials of anakinra have shown inhibition of the acute inflammatory response and prevention of HF after STEMI, but data on its effects based on CAD complexity are lacking. We performed a pooled secondary analysis of 139 patients with STEMI. The SYNTAX (Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery), SYNTAX II, and Gensini scores were calculated, and patients were divided into 2 groups below and above the median. We evaluated the effect of anakinra on the area-under-the-curve of high-sensitivity C-reactive protein (hsCRP-AUC) at 14 days, and the composite endpoint of new-onset HF, HF hospitalization, or all-cause death at 1-year follow-up using Kaplan-Meier survival curves, Cox regression analysis for hazard ratios (HRs), and tested interactions between subgroups. All 3 CAD complexity scores (SYNTAX, SYNTAX II, and Gensini) were associated with an increased risk of adverse events (HR 1.02-1.06, all P-values ≤0.025). We found no statistically significant interactions between CAD extent, measured as single-vessel or multivessel CAD, SYNTAX score ≤9 or >9, SYNTAX II score ≤24 or >24, Gensini score ≤32 or >32, and treatment effect of anakinra on hsCRP-AUC or the composite clinical endpoint (all P - values for interaction >0.05). In conclusion, among patients with STEMI, IL-1 blockade with anakinra significantly attenuated the acute inflammatory response and reduced the risk of HF-related events regardless of the spectrum of CAD complexity.

Enhancing percutaneous coronary intervention using TriVOCTNet: a multi-task deep learning model for comprehensive intravascular optical coherence tomography analysis

Neointimal coverage and stent apposition, as assessed from intravascular optical coherence tomography (IVOCT) images, are crucial for optimizing percutaneous coronary intervention (PCI). Existing state-of-the-art computer algorithms designed to automate this analysis often treat lumen and stent segmentations as separate target entities, applicable only to a single stent type and overlook automation of preselecting which pullback segments need segmentation, thus limit their practicality. This study aimed for an algorithm capable of intelligently handling the entire IVOCT pullback across different phases of PCI and clinical scenarios, including the presence and coexistence of metal and bioresorbable vascular scaffold (BVS), stent types. We propose a multi-task deep learning model, named TriVOCTNet, that automates image classification/selection, lumen segmentation and stent struts segmentation within a single network by integrating classification, regression and pixel-level segmentation models. This approach allowed a single-network, single-pass implementation with all tasks parallelized for speed and convenience. A joint loss function was specifically designed to optimize each task in situations where each task may or may not be present. Evaluation on 4,746 images achieved classification accuracies of 0.999, 0.997, and 0.998 for lumen, BVS, and metal stent features, respectively. The lumen segmentation performance showed a Euclidean distance error of 21.72 μm and Dice's coefficient of 0.985. For BVS struts segmentation, the Dice's coefficient was 0.896, and for metal stent struts segmentation, the precision was 0.895 and sensitivity was 0.868. TriVOCTNet highlights its clinical potential due to its fast and accurate results, and simplicity in handling all tasks and scenarios through a single system.

Catlet scoring system as a new predictor for in-stent restenosis in patients with chronic coronary artery disease undergoing percutaneous coronary intervention with drug-eluting stent

BACKGROUND

He's team have recently developed a new Coronary Artery Tree description and Lesion EvaluaTion (CatLet) angiographic scoring system, which is capable of accounting for the variability in coronary anatomy, and risk-stratifying patients with coronary artery disease. Preliminary studies have demonstrated its superiority over the the Synergy between percutaneous coronary intervention with Taxus and Cardiac Surgery (SYNTAX) score with respect to outcome predictions for acute myocardial infarction (AMI) patients. However, there are fewer studies on the prognostic in chronic coronary artery disease(CAD). This study aimed to clarify whether the CatLet score had a predictive value for in-stent restenosis(ISR) in patients with chronic coronary artery disease undergoing percutaneous coronary intervention with drug-eluting stent(DES).

METHODS

A total of 260 patients who were diagnosed with chronic CAD and underwent coronary DES implantation at the second affiliated Hospital of Wannan medical college in China were consecutively enrolled from January 2020 to June 2021.Finally, 164 patients underwent the second angiography after 2 years.According to whether ISR was detected at follow-up angiography, patients were divided into the ISR group (n = 26) and the non-ISR group (n = 139).

RESULTS

A total of 165 patients (46 women and 119 men) with a mean ages of 66.19 ± 10.54 years were finally enrolled in this study. Of these, ISR occurred in 26/165 chronic CAD patients (15.76%) by follow-up angiography. Univariate analysis showed that most baseline characteristics of the ISR and non-ISR group were similar. Patients in the ISR group had significantly the history of chronic obstructive pulmonary disease(COPD), adverse lesion characteristic, higher Catlet score compared with patients in the non-ISR group.The CatLet score was capable of predicting in-stent restenosis after adjustment for risk factors; The Multivariable-adjusted model showed good calibration and good discrimination (area under ROC curve = 0.7164) for ISR.

CONCLUDE

CatLet score is a new predictor of ISR in patients with chronic CAD after coronary DES implantation.

Peculiarities of in-Stent Thrombosis and Restenosis in Coronary Arteries Post-COVID-19: A Systematic Review of Clinical Cases and Case Series

Background

One of the most serious complications of coronary artery stenting is restenosis and in-stent thrombosis; their prevalence can reach 20-25%. Stent thrombosis can be acute (up to 24 hours), subacute (24 hours to 30 days), late (30 days to 1 year), and very late (> 1 year after previous stenting). In the patients with COVID-19 in intensive care units, the proportion of those with elevated troponin levels reached 25%.

Objective

Evaluation of the association between COVID-19 and the development of in-stent thrombosis and restenosis of the coronary arteries based on the analysis of clinical cases and case series.

Materials and Methods

We searched the PubMed and Scopus databases for relevant case reports and case series of stent restenosis and in-stent thrombosis associated with coronavirus infection (CVI) published between 2020 and the present. Thirty-eight full-text publications were screened and manually checked for analysis. We found 10 publications describing cases of thrombosis and restenosis of stents associated with coronavirus infection, of which only 2 were case series. In total, we analyzed 22 cases.

Results

In the structure of in-stent restenosis and thrombosis, 59.1% were very late, 9.1% were late; 18.2% were considered subacute events, and 13.6% were acute events. All cases were angiographically confirmed. The main location of restenosis or thrombosis was the left coronary artery (LAD) (51.1%), thrombosis of the right coronary artery (RCA) occurred in 27.3%, and location in circumflex artery was in 22.7%. All patients had COVID-19 confirmed by a PCR test or the presence of immunoglobulins G and M. In fourteen patients (54.5%), an X-ray examination showed the presence of bilateral polysegmental infiltration.

Conclusion

Analysis of publications demonstrates the association between restenosis and in-stent thrombosis in patients with coronary arteries disease (CAD) and coronavirus infection.

AB-Type Zwitterionic Hydrogel Paint

Zwitterionic hydrogels exhibit excellent nonfouling and hemocompatibility. However, the practical application of these materials as antifouling coatings for biomedical devices is hindered by several key challenges, including the harsh preparation conditions and the weak coating stability. Here, we present a two-component zwitterionic hydrogel paint for the in situ preparation of robust zwitterionic hydrogel coatings on various substrate surfaces without UV assistance. It is performed by the curing and adhesion of a zwitterionic hydrogel simultaneously through the ring opening reaction of epoxy and amino inspired by the successful commercial two-component epoxy structural glue. The obtained AB-type PSBMA coating can withstand water flow velocities of up to 15 m/s and still maintain its structural integrity and functional stability. It is noteworthy that the coating preparation process does not require the use of any organic solvent, which greatly simplifies the postprocessing steps for its application in medical devices. Moreover, the coating not only resists bacterial and cell adhesion but also exhibits favorable hemocompatibility. This approach offers a novel concept for the design of zwitterionic hydrogel coatings for biomedical devices.

Prevalence of metal implants among US adults aged 40 years and older

Metal implants are commonly used in clinical practice. However, little is known regarding the prevalence of metal implants. Therefore, this study aimed to evaluate the prevalence of metal implants in the United States (US) among individuals aged ≥ 40 years. This study conducted a serial cross-sectional analysis of US adults aged ≥ 40 years who participated in the National Health and Nutrition Examination Survey (NHANES) (2015-2016 and 2017-March 2020). Self-reported questionnaires were used to assess whether the participants had metal implants inside their bodies. The primary outcome was the prevalence of metal implants among adults aged 40 years and older. Furthermore, weighted logistic regression analysis was employed to determine the changes in the prevalence of metal implants from 2015 to March 2020. Moreover, this study investigated the variation in metal implant prevalence by demographic factors based on the pooled NHANES cycles. All analyses were conducted based on 3,736 participants from the NHANES 2015-2016 and 6,387 participants from the NHANES 2017-March 2020. This study observed a high prevalence of metal implants among adults aged 40 and older (2015-2016: 27.23%; 2017-March 2020: 31.53%). Moreover, the results of the weighted logistic regression analysis showed that the prevalence of metal implants significantly increased from 2015 to March 2020, especially among older individuals, men, and White individuals. In addition, the results of the weighted logistic regression analysis indicated that the metal implant prevalence differed by age and race/ethnicity, in which older individuals and White individuals showed a significantly higher prevalence of metal implants than younger individuals and non-White individuals, respectively. There was a high prevalence of metal implants among US adults aged 40 and older, and the prevalence of metal implants significantly increased from 2015 to March 2020. Therefore, more attention needs to be paid to this special population, and it may be necessary to ensure accessibility and affordability and assess the potential long-term health impacts of metal implants, considering the increased prevalence of metal implants.

Genotype-Guided P2Y12 Inhibitor Monotherapy Within 7 Days of Percutaneous Coronary Intervention in High Bleeding Risk Patients: The CHAMP Trial - A Pilot Study and Safety Assessment

OBJECTIVE

To test the feasibility and safety of genotype guidance in the selection of P2Y12 monotherapy within 1 week of percutaneous coronary interventions (PCIs) among patients with high bleeding risk (HBR).

PATIENT AND METHODS

The study was a single-center, open-label, pilot trial. Patients (n=100) with HBR (as defined by an academic research consortium) after successful PCI received dual antiplatelet therapy with clopidogrel and aspirin. Following availability of cytochrome P450 2C19 (CYP2C19) genotype results (mean, 2.9 days), aspirin was discontinued. Normal, rapid, or ultrarapid CYP2C19 metabolizers continued clopidogrel monotherapy for 90 days whereas loss-of-function allele carriers switched to prasugrel or ticagrelor monotherapy. The primary safety endpoints were a composite of post-dismissal cardiac death/spontaneous myocardial infarction less than 30 days or stent thrombosis <90 days of discharge. The subjects also underwent post-dismissal assessment for BARC (Bleeding Academic Research Consortium) type 3 or 5 bleeding, all-cause death, any MI, and/or repeat revascularization up to 90 days.

RESULTS

There were 98 patients with complete data (median age, 76.5 years, 36% women; 49% acute coronary syndrome). Sixty-nine (70.4%) were normal, rapid, or ultrarapid metabolizers and continued clopidogrel monotherapy, and 29 (29.6%) were intermediate CYP2C19 metabolizers and received monotherapy with prasugrel (n=21) or ticagrelor (n=8). The mean duration of dual antiplatelet therapy was 5.1 days. During 90-day follow-up, no patient died, there was one possible stent thrombosis, and three patients on clopidogrel had Bleeding Academic Research Consortium type 3 bleeding events.

CONCLUSION

Genotype-guided P2Y12 inhibitor monotherapy within a week of PCI is feasible and likely safe in patients with HBR (CHAMP [Clopidogrel With High Bleeding Risk and Adverse Events With Monotherapy in Patients Undergoing Percutaneous Coronary Interventions]; NCT05223335).

The Effects of Nicotine on Re-endothelialization, Inflammation, and Neoatherosclerosis After Drug-Eluting Stent Implantation in a Porcine Model

BACKGROUND AND OBJECTIVES

Cigarette smoking is a major risk factor for atherosclerosis. Nicotine, a crucial constituent of tobacco, contributes to atherosclerosis development and progression. However, evidence of the association between nicotine and neointima formation is limited. We aimed to evaluate whether nicotine enhances neointimal hyperplasia in the native epicardial coronary arteries of pigs after percutaneous coronary intervention (PCI) with drug-eluting stents (DES).

METHODS

After coronary angiography (CAG) and quantitative coronary angiography (QCA), we implanted 20 DES into 20 pigs allocated to 2 groups: no-nicotine (n=10) and nicotine (n=10) groups. Post-PCI CAG and QCA were performed immediately. Follow-up CAG, QCA, optical coherence tomography (OCT), and histopathological analyses were performed 2 months post-PCI.

RESULTS

Despite intergroup similarities in the baseline QCA findings, OCT analysis showed that the nicotine group had a smaller mean stent and lumen areas, a larger mean neointimal area, greater percent area stenosis, and higher peri-strut fibrin and inflammation scores than the no-nicotine group. In immunofluorescence analysis, the nicotine group displayed higher expression of CD68 and α-smooth muscle actin but lower CD31 expression than the no-nicotine group.

CONCLUSIONS

Nicotine inhibited re-endothelialization and promoted inflammation and NIH after PCI with DES in a porcine model.

Carotid single- and dual-layer stents reduce the wall adhesion of platelets by influencing flow and cellular transport

An ongoing thrombosis on a ruptured atherosclerotic plaque in the carotid may cause stroke. The primary treatment for patients with tandem lesion is stenting. Dual-layer stents have been introduced as an alternative to single-layer stents for elective and emergent carotid artery stenting. While the dual-layer structure shows promise in reducing plaque prolapse through the stent struts and with it the occurrence of post-procedural embolism, there are early signs that this newer generation of stents is more thrombogenic. We investigate a single- and a dual-layer stent design to assess their influence on a set of thrombosis-related flow factors in a novel setup of combined experiments and simulations. The in vitro results reveal that both stents reduce thrombus formation by approximately 50% when human anticoagulated whole blood was perfused through macrofluidic flow chambers coated with either collagen or human atherosclerotic plaque homogenates. Simulations predict that the primary cause is reduced platelet presence in the vicinity of the wall, due to the influence of stents on flow and cellular transport. Both stents significantly alter the near-wall flow conditions, modifying shear rate, shear gradient, cell-free zones, and platelet availability. Additionally, the dual-layer stent has further increased local shear rates on the inner struts. It also displays increased stagnation zones and reduced recirculation between the outer-layer struts. Finally, the dual-layer stent shows further reduced adhesion over an atherosclerotic plaque coating. The novel approach presented here can be used to improve the design optimization process of cardiovascular stents in the future by allowing an in-depth study of the emerging flow characteristics and agonist transport.

Safety and efficacy of antiplatelet therapy in patients with intermediate coronary artery stenosis and deferred revascularization

INTRODUCTION AND OBJECTIVES

This study investigated the safety and efficacy of antiplatelet therapy in patients with intermediate coronary artery stenosis who underwent deferred revascularization due to their fractional flow reserve (FFR).

METHODS

A nationwide cohort study was conducted using the Korean National Health Insurance Service database. A total of 4657 patients with intermediate coronary artery stenosis who underwent deferred revascularization due to their FFR were identified from 2013 to 2020. FFR was indicated in patients with no prior evidence of myocardial ischemia and intermediate coronary artery stenosis (50%-70%) as determined by quantitative coronary angiography. Patients were classified according to whether antiplatelet therapy was initiated after the index procedure. The primary efficacy outcome was major adverse cardiac and cerebrovascular events (MACCE), a composite of all-cause death, myocardial infarction, unplanned revascularization, and stroke, during a 5-year follow-up period. The primary safety outcome was any gastrointestinal bleeding.

RESULTS

After propensity score matching, there were 1634 patients in the antiplatelet therapy group and 1634 in the nonantiplatelet therapy group. The risk of MACCE was similar between the 2 groups (24.8% vs 24.7%; adjusted HR, 0.97; 95%CI, 0.84-1.13; P=0.745). The risk of gastrointestinal bleeding was higher in the antiplatelet therapy group than in the nonantiplatelet therapy group (2.2% vs 1.2%; aHR, 2.07; 95%CI, 1.08-4.00). These results were similar in subgroup analyses.

CONCLUSIONS

In patients with intermediate coronary artery stenosis who underwent deferred revascularization due to their FFR, antiplatelet therapy may increase the risk of gastrointestinal bleeding without reducing the risk of future ischemic events.

Identification of endothelial protein C receptor as a novel druggable agonistic target for reendothelialization promotion and thrombosis prevention of eluting stent

The commercially available drug-eluting stent with limus (rapamycin, everolimus, etc.) or paclitaxel inhibits smooth muscle cell (SMC), reducing the in-stent restenosis, whereas damages endothelial cell (EC) and delays stent reendothelialization, increasing the risk of stent thrombosis (ST) and sudden cardiac death. Here we present a new strategy for promoting stent reendothelialization and preventing ST by exploring the application of precise molecular targets with EC specificity. Proteomics was used to investigate the molecular mechanism of EC injury caused by rapamycin. Endothelial protein C receptor (EPCR) was screened out as a crucial EC-specific effector. Limus and paclitaxel repressed the EPCR expression, while overexpression of EPCR protected EC from coating (eluting) drug-induced injury. Furthermore, the ligand activated protein C (APC), polypeptide TR47, and compound parmodulin 2, which activated the target EPCR, promoted EC functions and inhibited platelet or neutrophil adhesion, and enhanced rapamycin stent reendothelialization in the simulated stent environment and in vitro. In vivo, the APC/rapamycin-coating promoted reendothelialization rapidly and prevented ST more effectively than rapamycin-coating alone, in both traditional metal stents and biodegradable stents. Additionally, overexpression or activation of the target EPCR did not affect the cellular behavior of SMC or the inhibitory effect of rapamycin on SMC. In conclusion, EPCR is a promising therapeutical agonistic target for pro-reendothelialization and anti-thrombosis of eluting stent. Activation of EPCR protects against coating drugs-induced EC injury, inflammatory cell, or platelet adhesion onto the stent. The novel application formula for APC/rapamycin-combined eluting promotes stent reendothelialization and prevents ST.

Assessment of the Predictive Ability of the Neutrophil-to-Lymphocyte Ratio in Patients with In-Stent Restenosis after COVID-19

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) is an independent predictor of the severity of coronary heart disease and COVID-19. This study aims to assess the predictive ability of the NLR in patients with in-stent restenosis after COVID-19.

MATERIALS AND METHODS

a cross-sectional study included 931 patients who underwent repeated myocardial revascularization between May 2020 and May 2023. The 420 patients of the main group had in-stent restenosis, of which 162 patients had COVID-19 previously. The control group included 511 patients without stent restenosis (107 patients had COVID-19 previously). All reported events were verified by hospital electronic records from the Complex Medical Information System.

RESULTS

The mean values of the NLR were 2.51 and 2.68 in the study groups, respectively. A statistically significant positive relationship in both groups was found between the NLR and troponin, D-dimer, C-reactive protein, creatinine, ALT, and AST. A statistically significant positive relationship was found between NLR and myocardial infarction (MI) in patients of both groups (p = 0.004; p < 0.001, respectively) and a negative relationship with the ejection fraction (p = 0.001; p < 0.036, respectively). An evaluation of the predictive ability of the clinical and laboratory predictors of recurrent myocardial infarction shows a high degree of utility of this model. The area under the ROC curve for AUC for NLR was 0.664 with 95% CI from 0.627 to 0.700 (p < 0.001).

CONCLUSIONS

NLR is one of the significant factors for predicting the development of adverse outcomes in patients with revascularized myocardium after COVID-19.

ESR Essentials: imaging in stable chest pain - practice recommendations by ESCR

Stable chest pain is a common symptom with multiple potential causes. Non-invasive imaging has an important role in diagnosis and guiding management through the assessment of coronary stenoses, atherosclerotic plaque, myocardial ischaemia or infarction, and cardiac function. Computed tomography (CT) provides the anatomical evaluation of coronary artery disease (CAD) with the assessment of stenosis, plaque type and plaque burden, with additional functional information available from CT fractional flow reserve (FFR) or CT myocardial perfusion imaging. Stress magnetic resonance imaging, nuclear stress myocardial perfusion imaging, and stress echocardiography can assess myocardial ischaemia and other cardiac functional parameters. Coronary CT angiography can be used as a first-line test for many patients with stable chest pain, particularly those with low to intermediate pre-test probability. Functional testing may be considered for patients with known CAD, where the clinical significance is uncertain based on anatomical testing, or in patients with high pre-test probability. This practice recommendations document can be used to guide the selection of non-invasive imaging for patients with stable chest pain and provides brief recommendations on how to perform and report these diagnostic tests. KEY POINTS: The selection of non-invasive imaging tests for patients with stable chest pain should be based on symptoms, pre-test probability, and previous history. Coronary CT angiography can be used as a first-line test for many patients with stable chest pain, particularly those with low to intermediate pre-test probability. Functional testing can be considered for patients with known CAD, where the clinical significance of CAD is uncertain based on anatomical testing, or in patients with high pre-test probability. KEY RECOMMENDATIONS: Non-invasive imaging is an important part of the assessment of patients with stable chest pain. The selection of non-invasive imaging test should be based on symptoms, pre-test probability, and previous history. (Level of evidence: High). Coronary CT angiography can be used as a first line test for many patients with stable chest pain, particularly those with low to intermediate pre-test probability. CT provides information on stenoses, plaque type, plaque volume, and if required functional information with CT fractional flow reserve or CT perfusion. (Level of evidence: High). Functional testing can be considered for patients with known CAD, where the clinical significance of CAD is uncertain based on anatomical testing, or in patients with high pre-test probability. Stress MRI, SPECT, PET, and echocardiography can provide information on myocardial ischemia, along with cardiac functional and other information. (Level of evidence: Medium).

Unravelling the progress and potential of drug-eluting stents and drug-coated balloons in cardiological insurgencies

AIM

Coronary artery disease (CAD) is the leading cause of mortality. Though percutaneous transluminal angioplasty followed by stenting is still the default treatment of choice for revascularization of obstructive CAD, the high rate of restenosis compromises the outcomes of endovascular procedures. To overcome restenosis, drug-eluting stents (DES) and drug-coated balloons (DCB) are designed that release antiproliferative drugs like sirolimus, paclitaxel, everolimus, etc., over time to inhibit cell growth and proliferation. Our review aims to summarize the challenges and progress of DES/DCBs in clinical settings.

MATERIAL AND METHODS

The comprehensive review, search and selection encompasses in relevant articles through Google Scholar, Springer online, Cochrane library and PubMed that includes research articles, reviews, letters and communications, various viewpoints, meta-analyses, randomized trials and quasi-randomized trials. Several preclinical and clinical data have been included from National Institutes of Health and clinicaltrials.gov websites.

KEY FINDINGS

Challenges like delayed endothelialization, stent thrombosis (ST), and inflammation was prominent in first-generation DES. Second-generation DES with improved designs and drug coatings enhanced biocompatibility with fewer complications. Gradual absorption of bioresorbable DES over time mitigated long-term issues associated with permanent implants. Polymer-free DES addressed the inflammation concerns but still, they leave behind metallic stents in the vasculature. As an alternative therapeutic strategy, DCB were developed to minimize inflammation in the vessel. Although both DES and DCBs have shown considerable progress, challenges persist.

SIGNIFICANCE

This review illustrates the advancements in the designs, preparation technologies, biodegradable materials, and drugs used as well as challenges associated with DES and DCBs in clinical settings.

Stable and Thin-Polymer-Based Modification of Neurovascular Stents with 2-Methacryloyloxyethyl Phosphorylcholine Polymer for Antithrombogenicity

The advent of intracranial stents has revolutionized the endovascular treatment of cerebral aneurysms. The utilization of stents has rendered numerous cerebral aneurysm amenable to endovascular treatment, thereby obviating the need for otherwise invasive open surgical options. Stent placement has become a mainstream approach because of its safety and efficacy. However, further improvements are required for clinically approved devices to avoid the frequent occurrence of thrombotic complications. Therefore, controlling the thrombotic complications associated with the use of devices is of significant importance. Our group has developed a unique stent coated with a 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymer. In this study, the surface characteristics of the polymer coating were verified using X-ray photoelectron spectroscopy and atomic force microscopy. Subsequently, the antithrombotic properties of the coating were evaluated by measuring platelet count and thrombin-antithrombin complex levels of whole human blood after 3 h of incubation in a Chandler loop model. Scanning electron microscopy was utilized to examine thrombus formation on the stent surface. We observed that MPC polymer-coated stents significantly reduced thrombus formation as compared to bare stents and several clinically approved devices. Finally, the coated stents were further analyzed by implanting them in the internal thoracic arteries of pigs. Angiographic imaging and histopathological examinations that were performed one week after implantation revealed that the vascular lumen was well maintained and coated stents were integrated within the vascular endothelium without inducing adverse effects. Thus, we demonstrated the efficacy of MPC polymer coating as a viable strategy for avoiding the thrombotic risks associated with neurovascular stents.

Immediate vs. multistage revascularization of non-infarct coronary artery(-ies) in patients with hemodynamically stable multivessel disease acute myocardial infarction: a systematic review and meta-analysis

BACKGROUND

Untreated multivessel disease (MVD) in acute myocardial infarction (AMI) has been linked to a higher risk of recurrent ischemia and death within one year . Current guidelines recommend percutaneous coronary intervention (PCI) for significant non-infarct artery (-ies) (non-IRA) stenosis in hemodynamically stable AMI patients with MVD, either during or after successful primary PCI, within 45-days. However, deciding the timing of revascularization for non-IRA in cases of MVD is uncertain.

METHODS

This meta-analysis was performed based on PRISMA guidelines after registering in PROSPERO (CRD42023472652). Databases were searched for relevant articles published before 10 November 2023. Pertinent data from the included studies were extracted and analyzed using RevMan v5.4.

RESULTS

Out of 640 studies evaluated, there were 13 RCTs with 5144 patients with AMI with MVD. The immediate non-IRA PCI is associated with a significantly lower occurrence of unplanned ischemia-driven PCI (OR 0.60; confidence interval [CI] 0.44-0.83) and target-vessel revascularization (OR 0.72; CI 0.53-0.97) . Although there is a favorable trend for major adverse cardiovascular and cerebrovascular events (MACCE), nonfatal AMI, cerebrovascular events, and major bleeding in the immediate non-culprit artery (-ies) PCI, those were statistically non-significant. Similarly, all-cause mortality, cardiovascular mortality, stent thrombosis, and acute renal insufficiency did not show significant differences between two groups.

CONCLUSION

Among hemodynamically stable patients with multivessel AMI, the immediate PCI strategy was superior to the multistage PCI strategy for the unplanned ischemia-driven PCI and target-vessel revascularization while odds are favorable in terms of MACCE, nonfatal AMI, cerebrovascular events, and major bleeding at longest follow-up.

Detection of Blood Clots Using a Whole Stent as an Active Implantable Biosensor

Many cardiovascular problems stem from blockages that form within the vasculature and often treatment includes fitting a stent through percutaneous coronary intervention. This offers a minimally invasive therapy but re-occlusion through restenosis or thrombosis formation often occurs post-deployment. Research is ongoing into the creation of smart stents that can detect the occurrence of further problems. In this study, it is shown that selectively metalizing a non-conductive stent can create a set of electrodes that are capable of detecting a build-up of material around the stent. The associated increase in electrical impedance across the electrodes is measured, testing the stent with blood clot to mimic thrombosis. It is shown that the device is capable of sensing different amounts of occlusion. The stent can reproducibly sense the presence of clot showing a 16% +/-3% increase in impedance which is sufficient to reliably detect the clot when surrounded by explanted aorta (one sample t-test, p = 0.009, n = 9). It is demonstrated that this approach can be extended beyond the 3D printed prototypes by showing that it can be applied to a commercially available stent and it is believed that it can be further utilized by other types of medical implants.

Coronary stent failure: role of a blended approach with drug-coated balloons for complex lesions

The management of coronary artery disease by means of percutaneous approach have been focused initially to overcome the recoil and acute occlusion after vessel ballooning; therefore, to develop and improve metallic stent platforms, and later drug-eluting technologies. Contemporarily, the necessity emerged to optimize interventional procedures using functional physiologic tests and intravascular imaging guidance, but still stent failures, especially in the complex lesion setting, continue to be not negligible. This comprehensive review is focused on the technology of drug-coated balloons as a tool to treat coronary artery disease without the need for metal implantation but still eluting antirestenotic drugs such as paclitaxel or sirolimus. We delve into these technologies, the drugs, the technical aspects of the deployment and the most updated evidence also proposing a dedicated interventional algorithm. There is solid data to support the use of drug-coated balloons in patients with in-stent restenosis and de-novo small coronary artery disease but also new evidence with promising results from recent studies indicate the feasibility of this approach in complex coronary interventions, bifurcation lesions and larger coronary vessels. In this state-of-the-art review, we also propose a blended approach based on the combination of drug-eluting stents and drug-coated balloons, keeping in mind the necessity to reduce the total stent length in order to reduce the long-term risk of complications.

Comparison study of surface-initiated hydrogel coatings with distinct side-chains for improving biocompatibility of polymeric heart valves

Polymeric heart valves (PHVs) present a promising alternative for treating valvular heart diseases with satisfactory hydrodynamics and durability against structural degeneration. However, the cascaded coagulation, inflammatory responses, and calcification in the dynamic blood environment pose significant challenges to the surface design of current PHVs. In this study, we employed a surface-initiated polymerization method to modify polystyrene-block-isobutylene-block-styrene (SIBS) by creating three hydrogel coatings: poly(2-methacryloyloxy ethyl phosphorylcholine) (pMPC), poly(2-acrylamido-2-methylpropanesulfonic acid) (pAMPS), and poly(2-hydroxyethyl methacrylate) (pHEMA). These hydrogel coatings dramatically promoted SIBS's hydrophilicity and blood compatibility at the initial state. Notably, the pMPC and pAMPS coatings maintained a considerable platelet resistance performance after 12 h of sonication and 10 000 cycles of stretching and bending. However, the sonication process induced visible damage to the pHEMA coating and attenuated the anti-coagulation property. Furthermore, the in vivo subcutaneous implantation studies demonstrated that the amphiphilic pMPC coating showed superior anti-inflammatory and anti-calcification properties. Considering the remarkable stability and optimal biocompatibility, the amphiphilic pMPC coating constructed by surface-initiated polymerization holds promising potential for modifying PHVs.

Sonodynamic therapy for the treatment of atherosclerosis

Atherosclerosis (AS) is a chronic inflammatory disease of large and medium-sized arteries that leads to ischemic heart disease, stroke, and peripheral vascular disease. Despite the current treatments, mortality and disability still remain high. Sonodynamic therapy (SDT), a non-invasive and localized methodology, has been developed as a promising new treatment for inhibiting atherosclerotic progression and stabilizing plaques. Promising progress has been made through cell and animal assays, as well as clinical trials. For example, the effect of SDT on apoptosis and autophagy of cells in AS, especially macrophages, and the concept of non-lethal SDT has also been proposed. In this review, we summarize the ultrasonic parameters and known sonosensitizers utilized in SDT for AS; we elaborate on SDT's therapeutic effects and mechanisms in terms of macrophages, T lymphocytes, neovascularization, smooth muscle cells, lipid, extracellular matrix and efferocytosis within plaques; additionally, we discuss the safety of SDT. A comprehensive summary of the confirmed effects of SDT on AS is conducted to establish a framework for future researchers.

Aortic Stenosis Management in Patients With Acute Hip Fracture

The treatment of severe aortic stenosis (SAS) has evolved rapidly with the advent of minimally invasive structural heart interventions. Transcatheter aortic valve replacement has allowed patients to undergo definitive SAS treatment achieving faster recovery rates compared to valve surgery. Not infrequently, patients are admitted/diagnosed with SAS after a fall associated with a hip fracture (HFx). While urgent orthopedic surgery is key to reduce disability and mortality, untreated SAS increases the perioperative risk and precludes physical recovery. There is no consensus on what the best strategy is either hip correction under hemodynamic monitoring followed by valve replacement or preoperative balloon aortic valvuloplasty to allow HFx surgery followed by valve replacement. However, preoperative minimalist transcatheter aortic valve replacement may represent an attractive strategy for selected patients. We provide a management pathway that emphasizes an early multidisciplinary approach to optimize time for hip surgery to improve orthopedic and cardiovascular outcomes in patients presenting with HFx-SAS.

Vascular stent with immobilized anti-inflammatory chemerin 15 peptides mitigates neointimal hyperplasia and accelerates vascular healing

Endovascular stenting is a safer alternative to open surgery for use in treating cerebral arterial stenosis and significantly reduces the recurrence of ischemic stroke, but the widely used bare-metal stents (BMSs) often result in in-stent restenosis (ISR). Although evidence suggests that drug-eluting stents are superior to BMSs in the short term, their long-term performances remain unknown. Herein, we propose a potential vascular stent modified by immobilizing clickable chemerin 15 (C15) peptides on the stent surface to suppress coagulation and restenosis. Various characterization techniques and an animal model were used to evaluate the surface properties of the modified stents and their effects on endothelial injury, platelet adhesion, and inflammation. The C15-immobilized stent could prevent restenosis by minimizing endothelial injury, promoting physiological healing, restraining the platelet-leukocyte-related inflammatory response, and inhibiting vascular smooth muscle cell proliferation and migration. Furthermore, in vivo studies demonstrated that the C15-immobilized stent mitigated inflammation, suppressed neointimal hyperplasia, and accelerated endothelial restoration. The use of surface-modified, anti-inflammatory, endothelium-friendly stents may be of benefit to patients with arterial stenosis. STATEMENT OF SIGNIFICANCE: Endovascular stenting is increasingly used for cerebral arterial stenosis treatment, aiming to prevent and treat ischemic stroke. But an important accompanying complication is in-stent restenosis (ISR). Persistent inflammation has been established as a hallmark of ISR and anti-inflammation strategies in stent modification proved effective. Chemerin 15, an inflammatory resolution mediator with 15-aa peptide, was active at picomolar through cell surface receptor, no need to permeate cell membrane and involved in resolution of inflammation by inhibiting inflammatory cells adhesion, modulating macrophage polarization into protective phenotype, and reducing inflammatory factors release. The implications of this study are that C15 immobilized stent favors inflammation resolution and rapid re-endothelialization, and exhibits an inhibitory role of restenosis. As such, it helps the decreased incidence of ISR.

Procedural and one-year outcomes following drug-eluting stent and drug-coated balloon combination for the treatment of de novo diffuse coronary artery disease: the HYPER Study

BACKGROUND

De novo diffuse coronary artery disease (CAD) is a challenging scenario in interventional cardiology with limited treatment option, beside stent implantation. In this context, a hybrid approach, combining the use of drug-eluting stent (DES) and drug-coated balloon (DCB) to treat different segments of the same lesion (e.g. long lesion and/or true bifurcation), might be an interesting and alternative strategy to limit the metal amount. The aim of this study was to evaluate the safety and efficacy of a hybrid approach in addressing percutaneous treatment of de novo diffuse CAD.

METHODS

This was a prospective, multicenter study including patients affected by de novo diffuse CAD treated with a hybrid approach from April 2019 to December 2020. Angiographic and clinical data were collected. The primary endpoint was the one-year device-oriented composite endpoint (DOCE, cardiac death, target vessel myocardial infarction and ischemia-driven target lesion revascularization [ID-TLR]). Periprocedural myocardial infarctions and periprocedural success were included among secondary endpoints.

RESULTS

One hundred six patients were included, mean age was 68.2±10.2 years and 78.3% were male. De novo diffuse CAD consisted of 52.8% long lesions and 47.2% true bifurcation lesions. Significant increase in the final minimal lumen diameters and significant decrease in the final diameter stenosis were observed when compared to the baseline values in both DES- and DCB-target segments. Procedural success was 96.2%. DOCE at one-year was 3.7%, with all the adverse events characterized by ID-TLR.

CONCLUSIONS

Combination of DES and DCB could be a safe and effective treatment option for the treatment of de novo diffuse CAD (NCT03939468).

The Effect of Angiotensin Receptor Blockers on In-Stent Restenosis After Stent Implantation: A Meta-Analysis

AIM

Angiotensin receptor blockers (ARBs) have been shown to inhibit restenosis in vitro and in vivo, but the evidence found in humans is inconsistent. This study aimed to evaluate the effectiveness of ARBs in preventing in-stent restenosis after percutaneous coronary intervention (PCI).

METHOD

Databases including the Cochrane Library, MEDLINE, Web of Science, EMBASE, and CNKI were searched to collect randomised controlled trials on ARBs inhibiting restenosis that were published before October 2022. A total of 1,056 patients enrolled in eight trials were included in the study.

RESULTS

The ARBs group showed lower target lesion revascularisation than the control group (RR 0.54; 95% CI 0.34-0.86; p=0.01), but the restenosis incidence between these two groups was not statistically significant (RR 0.85; 95% CI 0.65-1.11; p>0.05).

CONCLUSION

This study found that ARBs might have a potential effect on reducing target lesion revascularisation after PCI in coronary heart disease patients but has no impact on angiographic restenosis.

A macrofluidic model to investigate the intrinsic thrombogenicity of clinically used stents and develop less thrombogenic stents

Microfluidic blood flow models have been instrumental to study the functions of blood platelets in hemostasis and arterial thrombosis. However, they are not suited to investigate the interactions of platelets with the foreign surfaces of medical devices such as stents, mainly because of the dimensions and geometry of the microfluidic channels. Indeed, the channels of microfluidic chips are usually rectangular and rarely exceed 50 to 100 μm in height, impairing the insertion of clinically used stents. To fill this gap, we have developed an original macrofluidic flow system, which precisely reproduces the size and geometry of human vessels and therefore represents a biomimetic perfectly suited to insert a clinical stent and study its interplay with blood cells. The system is a circular closed loop incorporating a macrofluidic flow chamber made of silicone elastomer, which can mimic the exact dimensions of any human vessel, including the coronary, carotid or femoral artery. These flow chambers allow the perfect insertion of stents as they are implanted in patients. Perfusion of whole blood anticoagulated with hirudin through the device at relevant flow rates allows one to observe the specific accumulation of fluorescently labeled platelets on the stent surface using video-microscopy. Scanning electron microscopy revealed the formation of very large thrombi composed of tightly packed activated platelets on the stents.

Gamut of glycolytic enzymes in vascular smooth muscle cell proliferation: Implications for vascular proliferative diseases

Vascular smooth muscle cells (VSMCs) are the predominant cell type in the media of the blood vessels and are responsible for maintaining vascular tone. Emerging evidence confirms that VSMCs possess high plasticity. During vascular injury, VSMCs switch from a "contractile" phenotype to an extremely proliferative "synthetic" phenotype. The balance between both strongly affects the progression of vascular remodeling in many cardiovascular pathologies such as restenosis, atherosclerosis and aortic aneurism. Proliferating cells demand high energy requirements and to meet this necessity, alteration in cellular bioenergetics seems to be essential. Glycolysis, fatty acid metabolism, and amino acid metabolism act as a fuel for VSMC proliferation. Metabolic reprogramming of VSMCs is dynamically variable that involves multiple mechanisms and encompasses the coordination of various signaling molecules, proteins, and enzymes. Here, we systemically reviewed the metabolic changes together with the possible treatments that are still under investigation underlying VSMC plasticity which provides a promising direction for the treatment of diseases associated with VSMC proliferation. A better understanding of the interaction between metabolism with associated signaling may uncover additional targets for better therapeutic strategies in vascular disorders.

Off-Label Use of Peripheral Paclitaxel Drug-Coated Balloons in Management of Recurrent Coronary In-Stent Restenosis

Background

While not available for clinical use in the United States, dedicated drug-coated balloons (DCB) are currently under investigation for the management of coronary in-stent restenosis (ISR). Peripheral drug-coated balloons (P-DCB) have been used off-label for coronary ISR. Further data regarding this practice are needed. We aimed to describe outcomes in patients who underwent off-label P-DCB angioplasty for coronary ISR.

Methods

We analyzed data on P-DCB angioplasty for coronary ISR at a single high-volume center between April 1, 2015, and December 30, 2017. Demographic and procedural details were collected, with systematic follow-up as clinically indicated.

Results

Data from 31 patients treated with P-DCB angioplasty (mean age 68.0 ± 10.7 years) with coronary ISR (17 recurrent and 14 first time) were analyzed. Most patients presented with high-grade angina (81%) or myocardial infarction (13%). Treated ISR lesions were in native coronary arteries (68%), saphenous vein grafts (SVG, 23%), and the left internal mammary artery (10%). Diffuse intrastent ISR was common (69%) with a mean lesion length of 21.7 ± 12.4 mm. No postprocedural myocardial infarction occurred and 1 nonprocedural mortality occurred during index admission. At follow-up (median: 283, interquartile range [IQR]: 354 days), repeat angiography was performed in 19 patients (median: 212, IQR: 188 days), and 11 patients had target lesion recurrent ISR (Kaplan-Meier event-free survival estimate: 44.7%, 95% CI, 26.1%-76.5%).

Conclusions

In the absence of availability of dedicated coronary DCB, treatment of coronary ISR using P-DCB angioplasty was feasible, although follow-up demonstrated continued risk for recurrent ISR in this high-risk population.

Passivation protein-adhesion platform promoting stent reendothelialization using two-electron-assisted oxidation of polyphenols

Superhydrophilic surfaces play an important role in nature. Inspired by this, scientists have designed various superhydrophilic materials that are widely used in the field of biomaterials, such as PEG molecular brushes and zwitterionic materials. However, superhydrophilic coatings with only anti-fouling properties do not satisfy the requirements for rapid reendothelialization of cardiovascular stent surfaces. Herein, a novel polyphenol superhydrophilic surface with passivated protein-adsorption properties was developed using two-electron oxidation of dopamine and polyphenols. This coating has a multiscale effects: 1) macroscopically: anti-fouling properties of superhydrophilic; 2) microscopically: protein adhesion properties of active groups (quinone-, amino-, hydroxyphenyl groups and aromatic ring). Polyphenols not only enhance the ability of coating to passivate protein-adsorption, but also make the coating have polyphenol-related biological functions. Therefore, the polyphenol and passivated protein-adsorption platform together maintain the stability of the scaffold microenvironment. This, in turn, provides favorable conditions for the growth of endothelial cells on the scaffold surface. In vivo implantation of the coated stents into the abdominal aorta resulted in uniform and dense endothelial cells covering the surface of the neointima. Moreover, new endothelial cells secreted large amounts of functional endothelial nitric oxide synthase like healthy endothelial cells. These results indicate that the polyphenol superhydrophilic coating potentially resists intra-stent restenosis and promotes surface reendothelialization. Hence, polyphenol superhydrophilic coatings with passivated protein-adsorption properties constructed by two-electron-assisted oxidation are a highly effective and versatile surface-modification strategy for implantable cardiovascular devices.

Comprehensive clinical outcomes of drug-coated balloon treatment for coronary artery disease. Insights from a single-center experience

BACKGROUND

Some clinical trials have verified the efficacy and safety of paclitaxel drug-coated balloon (DCB) for small vessel coronary artery disease. However, nonsmall vessel and calcified lesions received less attention.

AIMS

This study aimed to investigate the efficacy of DCB treatment for various types of coronary artery lesions, including not only small vessel disease but also nonsmall vessel disease and calcified lesions. In this real-world clinical practice study, in-stent restenosis was excluded.

METHODS

This study consecutively included 934 patients with 1751 nonstented lesions who received DCB at a cardiovascular center in Kyoto Katsura Hospital in Japan between 2009 and 2012 and 2014 to 2019. This study enrolled and retrospectively analyzed all of the patients. Eligible patients routinely underwent follow-up angiography at 6-8 months after percutaneous coronary intervention. The primary endpoint includes target lesion revascularization (TLR) during follow-up. Further, this study calculated the predictor of TLR using multivariate analysis.

RESULTS

This study included the lesions involving 46.4% of type B2/C, 26.9% with severe calcification, and 6.0% with DCB restenosis. Mean DCB diameter and length were 2.75 ± 0.51 mm and 24.2 ± 9.6 mm, respectively. The median follow-up duration was 18 months. Follow-up angiography revealed a TLR rate of 9% and a restenosis rate of 9%. This study identified hemodialysis and current smoking as independent TLR predictors.

CONCLUSION

In routine clinical practice, the effectiveness of DCB was observed consistently across various types of coronary artery disease.

Intrastent Restenosis: A Comprehensive Review

The primary objective of this paper is to delineate and elucidate the contemporary advancements, developments, and prevailing trajectories concerning intrastent restenosis (ISR). We aim to provide a thorough overview of the most recent developments in this area, covering various aspects such as pathophysiological insights, therapeutic approaches, and new strategies for tackling the complex challenges of ISR in modern clinical settings. The authors have undertaken a study to address a relatively new medical challenge, recognizing its significant impact on the morbidity and mortality of individuals with cardiovascular diseases. This effort is driven by the need to fully understand, analyze, and possibly improve the outcomes of this emerging medical issue within the cardiovascular disease field. We acknowledge its considerable clinical implications and the necessity for innovative methods to mitigate its effects on patient outcomes. Therefore, our emphasis was directed towards elucidating the principal facets of the condition's prevalence, expounding upon the foundational mechanisms underscoring conspicuous restenosis, and delineating the risk factors relevant in shaping the contemporary landscape of diagnostic and therapeutic modalities. This thorough examination aims to provide a comprehensive understanding of the various dimensions of the condition, including epidemiological data, pathophysiological complexities, and clinical considerations critical for evaluating and enhancing current diagnostic and treatment approaches.

Association of Periprocedural Inflammatory Activation With Increased Risk for Early Coronary Stent Thrombosis

BACKGROUND

Stent thrombosis is a rare but deleterious event. Routine coronary angiography with percutaneous coronary intervention (PCI) is often deferred in the presence of laboratory markers of acute inflammation to prevent complications. The aim of this study was to investigate whether an acute inflammatory state is associated with an increased risk of early stent thrombosis.

METHODS AND RESULTS

Within a prospective single-center registry, the association between preprocedural acute inflammatory activation, defined as C-reactive protein plasma levels >50 mg/L or a leukocyte count >12 g/L, and occurrence of early (≤30 days) stent thrombosis was evaluated. In total, 11 327 patients underwent PCI and of those, 6880 patients had laboratory results available. 49.6% of the study population received PCI for an acute coronary syndrome and 50.4% for stable ischemic heart disease. In patients with signs of acute inflammatory activation (24.9%), PCI was associated with a significantly increased risk for stent thrombosis (hazard ratio, 2.89; P<0.00001), independent of age, sex, kidney function, number and type of stents, presence of multivessel disease, choice of P2Y12 inhibitor, and clinical presentation. Elevated laboratory markers of acute inflammation were associated with the occurrence of stent thrombosis in both patients with acute coronary syndrome (hazard ratio, 2.63; P<0.001) and in patients with stable ischemic heart disease (hazard ratio, 3.57; P<0.001).

CONCLUSIONS

An acute inflammatory state at the time of PCI was associated with a significantly increased risk of early stent thrombosis. Evidence of acute inflammation should result in deferred PCI in elective patients, while future studies are needed for patients with acute coronary syndrome.

Factors associated with early, late, and very late stent thrombosis among patients with acute coronary syndrome undergoing coronary stent placement: analysis from the ATLAS ACS 2-TIMI 51 trial

Background

Stent thrombosis (ST) is an uncommon but serious complication of stent implantation. This study aimed to explore factors associated with early, late, and very late ST to help guide risk assessment and clinical decision-making on ST.

Methods

The analysis included patients who received stent placement for the index acute coronary syndrome (ACS). Cumulative incidence of ST was assessed at 30 days (early ST), 31-360 days (late ST), 361-720 days (very late ST), and up to 720 days. Cox proportional hazards models were used to assess associations between ST and various factors, including patient characteristics [i.e., age, sex, ACS presentation, history of hypertension, smoking, diabetes, prior myocardial infarction (MI), heart failure, prior ischemic stroke, and cancer], laboratory tests [i.e., positive cardiac biomarker, hemoglobin, platelet count, white blood cell (WBC) count], and treatment [i.e., drug-eluting stent (DES) vs. bare-metal stent (BMS) and anticoagulant with rivaroxaban vs. placebo].

Results

Among the 8,741 stented patients, 155 ST events (2.25%) occurred by Day 720. The cumulative incidences of early, late, and very late ST were 0.80%, 0.81%, and 0.77%, respectively. After multivariable adjustment, age ≥ 75 [hazard ratio (HR) = 2.13 (95% confidence interval, CI: 1.26-3.60)], a history of prior MI [HR = 1.81 (95% CI: 1.22-2.68)], low hemoglobin level [HR = 2.34 (95% CI: 1.59-3.44)], and high WBC count [HR = 1.58 (95% CI: 1.02-2.46)] were associated with a greater risk of overall ST, whereas DES [HR = 0.56 (95% CI: 0.38-0.83)] and rivaroxaban therapy [HR = 0.63 (95% CI: 0.44-0.88)] were associated with a lower risk of overall ST up to 720 days. Low hemoglobin level and high WBC count were associated with early ST (low hemoglobin: HR = 2.35 [95% CI: 1.34-4.12]; high WBC count: HR = 2.11 [95% CI: 1.17-3.81]). Low hemoglobin level and prior MI were associated with a greater risk of late ST (low hemoglobin: HR = 2.32 [95% CI: 1.26-4.27]; prior MI: HR = 2.98 [95% CI: 1.67-5.31]), whereas DES was associated with a lower risk of late ST [HR = 0.33 (95% CI: 0.16-0.67)]. Age ≥75 years was associated with very late ST.

Conclusion

The study identified positive and negative associations with early, late, and very late ST. These variables may be useful in constructing risk assessment models for ST.

Clinical Trial Registration

http://www.clinicaltrials.gov, identifier NCT00809965.

Integrative bioinformatics analysis identifies APOB as a critical biomarker in coronary in-stent restenosis

Aim: Coronary artery disease (CAD) is a major contributor to the worldwide prevalence of cardiovascular disease. In-stent restenosis (ISR) is a common complication which can lead to stent implantation failure, necessitating repeated intervention and presenting a significant obstacle for CAD management. Methods: To accurately assess and determine the hub genes associated with ISR, CAD databases from the Gene Expression Omnibus were utilized and weighted gene coexpression network analysis was employed to identify key genes in blood samples. Results: APOB was identified as a risk gene for ISR occurrence. Subsequent correlation analysis of APOB demonstrated a positive association with ISR. Clinical validation further confirmed the predictive value of APOB in ISR detection. Conclusion: We have identified APOB as a critical predictive biomarker for ISR in CAD patients.

Microvascular dysfunction following deferred stenting strategy in ST-segment elevation myocardial infarction: a case report

Background

ST-segment elevation myocardial infarction (STEMI) has traditionally been managed with immediate reperfusion of the culprit artery, primarily through percutaneous coronary intervention and stent placement. Emerging data are highlighting the crucial importance of post-infarct microcirculatory function assessment.

Case summary

This report presents a patient with an inferior STEMI who was successfully reperfused without stent implantation. Tools such as optical coherence tomography, fractional flow reserve, and positron emission tomography computed tomography N-13 ammonia were utilized, offering comprehensive insights into the anatomical and functional characteristics of both the epicardial vessel and microcirculation.

Discussion

The recovery of the reversible component of microcirculatory dysfunction, observable as early as 5 days post-infarction, might carry significant implications for clinical decision-making. Such insights can potentially influence contemporary treatment strategies, including the consideration of deferred stenting. This case underscores the significance of post-infarct microcirculatory function and its potential impact on therapeutic approaches.

Rationale and design of a randomized controlled trial: The effect of intensive lipid-lowering therapy with PCSK9 inhibitor on endothelial-coverage of stent strut after percutaneous coronary intervention (PCI) for patients with acute coronary syndrome (ACS): Optical coherence tomography (OCT) study (PIECES-OCT study)

BACKGROUND

For the patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI), dual antiplatelet therapy (DAPT) for at least 1 year is recommended in the guidelines to minimize the risk of stent thrombosis. Persistently uncovered stent strut means delayed neointima formation and extend the window of time in which the stent is prone to thrombosis. Previous studies showed that statins could improve post-stenting strut endothelial coverage for patients undergoing PCI. However, there are lack of evidences on whether early initiation of proprotein convertase subtilisin/Kexin type 9 monoclonal antibody (PCSK9mAb) after PCI in ACS patients can further improve the rate of stent strut coverage on the background of oral lipid-lowering therapy (LLT).

METHODS

This is a single-center, randomized trial to enroll 36 patients undergoing PCI with a clinical diagnosis of non-ST-segment elevation ACS. The baseline level of low-density lipoprotein cholesterol (LDL-C) of these patients are between 1.4 mmol/L and 3.4 mmol/L. Patients will be assigned to intensive lipid-lowering therapy (LLT) with PCSK9mAb group and conventional LLT without PCSK9mAb group for 12 weeks in a clinical follow-up setting according to 1: 1 randomization. the rate of stent strut endothelial coverage by optical coherence tomography (OCT) examination at 12 weeks after enrollment between the groups will be compared.

CONCLUSION

This will be the first study to investigate changes in the rate of stent strut endothelial coverage under intensive LLT with PCSK9mAb by OCT examination in ACS patients undergoing PCI. The finding of this study will provide clinical evidence for future research about the hypothesis of a novel strategy of "intensive LLT (PCSK9mAb + statin ± ezetimibe) combined with shortened DAPT duration" for ACS patients undergoing PCI.Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: ChiCTR2200063395.

Comparisons of drug-eluting balloon versus drug-eluting stent for the treatment of cancer patients presenting with acute myocardial infarction

BACKGROUND

Treatment for cancer patients presenting with acute myocardial infarction (AMI) remains challenging. The objective of the study was to investigate the safety and efficiency of drug eluting balloon (DEB) versus drug eluting stent (DES) in this high-risk group.

METHODS

Between 1st January 2017 and 1st January 2022, cancer patients admitted to Beijing Chaoyang Hospital with AMI were retrospectively enrolled. The primary endpoint was major adverse cardiovascular event (MACE). The secondary endpoints included major bleeding events, heart failure and cardiac complications.

RESULTS

A total of 164 cancer patients presenting with AMI were included in the final analysis. Patients treated with DEB had a numerically lower rate of MACE than those treated with DES during a median follow-up of 21.8 months (22.9% vs. 37.1%, p = 0.23). Patients treated with DEB had a trend towards lower rate of major bleeding events than patients treated with DES (6.3% vs. 18.1%, HR 2.96, 95% CI [0.88, 9.92], p = 0.08). There were no significant differences between the two groups with regards to the rate of heart failure (4.2% vs. 9.5%, p = 0.32) and cardiac complications (0.0% vs. 2.6%, p = 0.56).

CONCLUSIONS

The present study demonstrated that in cancer patients with AMI, DEB had a trend towards lower rate of major bleeding events and a numerically lower rate of MACE compared with DES.

Multilevel Assessment of Stent-Induced Inflammation in the Adjacent Vascular Tissue

A recent U.S. Food and Drug Administration report presented the currently available scientific information related to biological response to metal implants. In this work, a multilevel approach was employed to assess the implant-induced and biocorrosion-related inflammation in the adjacent vascular tissue using a mouse stent implantation model. The implications of biocorrosion on peri-implant tissue were assessed at the macroscopic level via in vivo imaging and histomorphology. Elevated matrix metalloproteinase activity, colocalized with the site of implantation, and histological staining indicated that stent surface condition and implantation time affect the inflammatory response and subsequent formation and extent of neointima. Hematological measurements also demonstrated that accumulated metal particle contamination in blood samples from corroded-stetted mice causes a stronger immune response. At the cellular level, the stent-induced alterations in the nanostructure, cytoskeleton, and mechanical properties of circulating lymphocytes were investigated. It was found that cells from corroded-stented samples exhibited higher stiffness, in terms of Young's modulus values, compared to noncorroded and sham-stented samples. Nanomechanical modifications were also accompanied by cellular remodeling, through alterations in cell morphology and stress (F-actin) fiber characteristics. Our analysis indicates that surface wear and elevated metal particle contamination, prompted by corroded stents, may contribute to the inflammatory response and the multifactorial process of in-stent restenosis. The results also suggest that circulating lymphocytes could be a novel nanomechanical biomarker for peri-implant tissue inflammation and possibly the early stage of in-stent restenosis. Large-scale studies are warranted to further investigate these findings.

Drug-Coated Balloon-Only Strategy for De Novo Coronary Artery Disease: A Meta-analysis of Randomized Clinical Trials

Backgrounds

Many clinical trials have demonstrated the value of drug-coated balloons (DCB) for in-stent restenosis. However, their role in de novo lesions is not well documented. The aim of this study is to evaluate the safety and efficacy of the DCB-only strategy compared to other percutaneous coronary intervention strategies for de novo coronary lesions.

Methods

The PubMed, Embase, Web of Science, and Cochrane Library Central Register of Controlled Trials (CENTRAL) electronic databases were searched for randomized controlled trials published up to May 6, 2023. The primary outcomes were major adverse cardiac events and late lumen loss.

Results

A total of eighteen trials with 3336 participants were included. Compared with drug-eluting stents, the DCB-only strategy was associated with a similar risk of major adverse cardiac events (risk ratio (RR) = 0.90; 95% confidence interval (CI): 0.59 to 1.37, P = 0.631) and a significant decrease in late lumen loss (standardized mean difference (SMD) = -0.29, 95% CI: -0.53 to -0.04, P = 0.021). This effect was consistent in subgroup analysis regardless of indication, follow-up time, drug-eluting stent type, and dual antiplatelet therapy duration. However, DCBs were inferior to DESs for minimum lumen diameter and percentage diameter stenosis. The DCB-only strategy showed significantly better outcomes for most endpoints compared to plain-old balloon angioplasty or bare metal stents.

Conclusions

Interventions with a DCB-only strategy are comparable to those of drug-eluting stents and superior to plain-old balloon angioplasty or bare metal stents for the treatment of selected de novo coronary lesions. Additional evidence is still warranted to confirm the value of DCB before widespread clinical utilization can be recommended.

Bleeding in acute coronary syndrome: from definitions, incidence, and prognosis to prevention and management

INTRODUCTION

In patients with acute coronary syndrome (ACS), the ischemic benefit of antithrombotic treatment is counterbalanced by the risk of bleeding. The recognition that bleeding events have prognostic implications (i.e. mortality) similar to recurrent ischemic events led to the development of treatment regimens aimed at balancing both ischemic and bleeding risks.

AREAS COVERED

This review aims at describing definitions, incidence, and prognosis related to bleeding events in ACS patients as well as bleeding-avoidance strategies for their prevention and management of bleeding complications.

EXPERT OPINION

Management of ACS patients has witnessed remarkable progress after the shift in focusing on the trade-off between ischemia and bleeding. Efforts in standardizing bleeding definitions will allow for better defining the prognostic impact of different types of bleeding events and enable to identify the high-bleeding risk patient. Such efforts will allow to balance the trade-off between the thrombotic and bleeding risk of the individual patient translating into better downward diagnostic and therapeutic decision-making. Novel strategies aiming at maximizing the safety and efficacy of antithrombotic regimens as well as the development of novel antithrombotic drugs and reversal agents and technological advances will allow for optimization of bleeding-avoidance strategies and management of bleeding complications.

Restoring endothelial function: shedding light on cardiovascular stent development

Complete endothelialization is highly important for maintaining long-term patency and avoiding subsequent complications in implanting cardiovascular stents. It not only refers to endothelial cells (ECs) fully covering the inserted stents, but also includes the newly formed endothelium, which could exert physiological functions, such as anti-thrombosis and anti-stenosis. Clinical outcomes have indicated that endothelial dysfunction, especially the insufficiency of antithrombotic and barrier functions, is responsible for stent failure. Learning from vascular pathophysiology, endothelial dysfunction on stents is closely linked to the microenvironment of ECs. Evidence points to inflammatory responses, oxidative stress, altered hemodynamic shear stress, and impaired endothelial barrier affecting the normal growth of ECs, which are the four major causes of endothelial dysfunction. The related molecular mechanisms and efforts dedicated to improving the endothelial function are emphasized in this review. From the perspective of endothelial function, the design principles, advantages, and disadvantages behind current stents are introduced to enlighten the development of new-generation stents, aiming to offer new alternatives for restoring endothelial function.

"Spongy skin" as a robust strategy to deliver 4-octyl itaconate for conducting dual-regulation against in-stent restenosis

The valid management of inflammation and precise inhibition of smooth muscle cells (SMCs) is regarded as a promising strategy for regulating vascular responses after stent implantation, yet posing huge challenges to current coating constructions. Herein, we proposed a spongy cardiovascular stent for the protective delivery of 4-octyl itaconate (OI) based on a "spongy skin" approach, and revealed the dual-regulation effects of OI for improving vascular remolding. We first constructed a "spongy skin" onto poly-l-lactic acid (PLLA) substrates, and realized the protective loading of OI with the highest dosage of 47.9 μg/cm2. Then, we verified the remarkable inflammation mediation of OI, and surprisingly revealed that the OI incorporation specifically inhibited SMC proliferation and phenotype switching, which contributed to the competitive growth of endothelial cells (EC/SMC ratio ∼ 5.1). We further demonstrated that OI at a concentration of 25 μg/mL showed significant suppression of the TGF-β/Smad pathway of SMCs, leading to the promotion of contractile phenotype and reduction of extracellular matrix. In vivo evaluation indicated that the successful delivery of OI fulfilled the inflammation regulation and SMCs inhibition, therefore suppressing the in-stent restenosis. This "spongy skin" based OI eluting system may serve as a new strategy for improving vascular remolding, and provides a potential concept for the treatment of cardiovascular diseases.

A novel polymer-free everolimus-eluting stent with a nitrogen-doped titanium dioxide film inhibits restenosis and thrombosis in a swine coronary model

BACKGROUND

Short-term outcomes regarding the safety and efficacy of a polymer-free everolimus-eluting stent (EES) with a nitrogen-doped titanium dioxide (N-TiO₂) film in a swine coronary model have been reported. However, the long-term results of the use of this type of stent have not yet been evaluated or compared to those of other polymer-free coronary stents. Therefore, this study aimed to determine the mid- to long-term safety and efficacy of a polymer-free EES with an N-TiO₂ film in a swine coronary model.

METHODS

Polymer-free EES with N-TiO₂ films (n = 30) and polymer-free sirolimus-eluting stents (SES; n = 30) were implanted in 30 pigs. Quantitative coronary analysis and optical coherence tomography were conducted immediately and at 1 (quantitative coronary analysis only), 3, and 6 months after stenting. Histopathologic examinations were performed at 1, 3, and 6 months after stenting.

RESULTS

The polymer-free EES group had a lower percentage of neointimal growth than the polymer-free SES group at 3 months (22.5% ± 11.4% vs. 32.1% ± 12.3%; p < 0.001). The polymer-free EES group had a lower fibrin score than the polymer-free SES group at 1 month (1.9 ± 0.45 vs. 2.5 ± 0.54; p = 0.001). The re-endothelialization rates were similar between groups. The polymer-free EES group had a lower percentage of the area of stenosis than the polymer-free SES group throughout the follow-up period.

CONCLUSIONS

The novel polymer-free EES with an N-TiO₂ film has superior safety and efficacy than the polymer-free SES at the 6-month follow-up in a swine model.

A coupled thermal-electrical-structural model for balloon-based thermoplasty treatment of atherosclerosis

OBJECTIVES

The outcome of balloon-based atherosclerosis thermoplasty is closely related to the temperature/stress distribution during the treatment. For precise prediction of a required thermal lesion in the heterogeneous and thin atherosclerotic vessel, a numerical model incorporating heat-induced tissue expansion or shrinkage and the strain caused by balloon dilation is necessary.

METHODS

A fully coupled thermal-electrical-structural new model was established. The model features a heterogeneous structure including eccentric plaque, healthy artery and surrounding tissue. Tissue expansion/shrinkage and hyperelasticity material model were taken into consideration. Different heating strategies and plaque mechanical properties were investigated. The temperature distribution was compared with the traditional thermal-electrical coupled model. The possibility of thermoplasty treatment using balloons with different sizes was also explored.

RESULTS

The temperature, the electrical intensity and the stress during the thermoplasty were obtained. Lower stress was found in the heating region where tissue shrinkage occurred. The ablation depth was predicted to be ∼0.42 mm larger without coupling the biomechanical influence. The mechanical properties and input condition significantly affect the temperature and stress distribution considering the small dimensions of the tissue. Besides, with a 12.5% reduction of balloon diameter, the largest Von Mises stress decreases by 25.4%.

CONCLUSIONS

It is confirmed that a coupled thermal-electrical-structural model is needed for precise temperature prediction in the balloon-based thermoplasty of the heterogeneous and thin tissue. The model presented may help with future development of optimized treatment planning considering both ablation depth and minimum stress.

Effects of Coupled-/soluble-Copper, Generating from Copper-doped Titanium Dioxide Nanotubes on Cell Response

BACKGROUND

Endothelialization in vitro is a very common method for surface modification of cardiovascular materials. However, mature endothelial cells are not suitable because of the difficulty in obtaining and immunogenicity.

METHODS

In this patent work, we determined the appropriate amount of copper by constructing a copper- loaded titanium dioxide nanotube array that can catalyze the release of nitric oxide, compared the effects of coupled-/soluble-copper on stem cells, and then induced stem cells to differentiate into endothelial cells.

RESULTS

The results showed that it had a strong promotion effect on the differentiation of stem cells into endothelial cells, which might be used for endothelialization in vitro.

CONCLUSION

SEM and EDS results prove that a high content of copper ions are indeed doped onto the surface of nanotubes with small amounts of Cu release. The release of NO confirms that the release of several samples within a period of time is within the physiological concentration.

Vascular healing in high-bleeding-risk patients at 3-month after everolimus-eluting stent versus biolimus A9-coated stent implantation: insights from analysis of optical coherence tomography and coronary angioscopy

The prevalence of high-bleeding-risk (HBR) patients who undergo coronary stenting has been reported as 20-40%. This study sought to assess vascular healing in HBR patients by coronary angioscopy (CAS) and optical coherence tomography (OCT). We prospectively analyzed 38 HBR patients with coronary artery disease who successfully underwent everolimus-eluting stent (EES) implantation (20 patients, 23 lesions) or drug-coated stent (DCS) implantation (18 patients, 18 lesions). Follow-up coronary angiography, CAS, and OCT were planned at 3 months after the procedure. The clinical characteristics and inclusion criteria of HBR were comparable between groups. CAS analysis showed that mean yellow color grade was significantly higher with EES than with DCS (1.33 [1.0, 1.67] vs. 1.0 [0.67, 1.5]; P = 0.04). In contrast, OCT analysis demonstrated that most struts in both groups were well-apposed struts with neointimal coverage (93.9% each; P = 1.00), and percentages of the mean neointimal area were comparable between EES and DCS (4.4 ± 3.5 mm² vs. 4.5 ± 4.1 mm²; P = 0.91). The frequency of uncovered struts was significantly lower with EES than with DCS (2.4% vs. 5.3%; P < 0.001), whereas the frequency of malapposed struts was significantly higher with EES than with DCS (3.5% vs. 0.8%; P < 0.001). During follow-up, no stent thrombosis or major bleeding complications were encountered in either group. Among HBR patients, both EES and DCS demonstrated good vascular healing at 3-month follow-up with some different features in CAS and OCT assessments.