Long-Term Outcomes and Clinical Predictors of Mortality Following Occurrence of Stent Thrombosis

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.

Steps Toward Recapitulating Endothelium: A Perspective on the Next Generation of Hemocompatible Coatings

Endothelium, the lining in this blood vessel, orchestrates three main critical functions such as protecting blood components, modulating of hemostasis by secreting various inhibitors, and directing clot digestion (fibrinolysis) by activating tissue plasminogen activator. No other surface can perform these tasks; thus, the contact of blood and blood-contacting medical devices inevitably leads to the activation of coagulation, often causing device failure, and thromboembolic complications. This perspective, first, discusses the biological mechanisms of activation of coagulation and highlights the efforts of advanced coatings to recapitulate one characteristic of endothelium, hereafter single functions of endothelium and noting necessity of the synergistic integration of its three main functions. Subsequently, it is emphasized that to overcome the challenges of blood compatibility an endothelium-mimicking system is needed, proposing a synergy of bottom-up synthetic biology, particularly synthetic cells, with passive- and bioactive surface coatings. Such integration holds promise for developing advanced biomaterials capable of recapitulating endothelial functions, thereby enhancing the hemocompatibility and performance of blood-contacting medical devices.

Atherosclerotic Plaque Erosion: Mechanisms, Clinical Implications, and Potential Therapeutic Strategies-A Review

ABSTRACT

Atherosclerosis is an insidious and progressive inflammatory disease characterized by the formation of lipid-laden plaques within the intima of arterial walls with potentially devastating consequences. While rupture of vulnerable plaques has been extensively studied, a distinct mechanism known as plaque erosion (PE) has gained recognition and attention in recent years. PE, characterized by the loss of endothelial cell lining in the presence of intact fibrous cap, contributes to a significant and growing proportion of acute coronary events. However, despite a heterogeneous substrate underlying coronary thrombosis, treatment remains identical. This article provides an overview of atherosclerotic PE characteristics and its underlying mechanisms, highlights its clinical implications, and discusses potential therapeutic strategies.

Optical coherence tomography-guided versus angiography-guided percutaneous coronary intervention: A meta-analysis of randomized controlled trials

Background

Optical Coherence Tomography (OCT), a high-resolution imaging modality, guides stent implantation during percutaneous coronary intervention (PCI). However, OCT-guided PCI safety and efficacy data is limited.

Methods

MEDLINE, Embase, and Cochrane Central were searched for randomized controlled trials (RCTs) comparing OCT-guided PCI to Angiography-guided PCI from inception to August 2023. A random-effects model was used to pool risk ratios (RRs), mean differences (MDs), and 95% confidence intervals (CIs) for clinical endpoints.

Results

Our analysis included 5,139 patients from 11 studies. OCT-guided PCI resulted in a higher minimum stent area (MD = 0.35 [95 % CI, 0.21-0.49]; p < 0.00001), significantly reduced risk of cardiovascular mortality (RR = 0.56 [95 % CI, = 0.32-0.99]; p = 0.04), stent thrombosis (RR = 0.56 [95 % CI, 0.32-0.96]; p = 0.04), stent malapposition RR = 0.79 [95 % CI, 0.71-0.88]; p = < 0.0001) and major edge dissection (RR = 0.47 [95 % CI, 0.34-0.65]; p = <0.00001). However, no statistically significant difference was observed for all-cause mortality (RR = 0.71; p = 0.06), major adverse cardiovascular events (MACE) [RR = 0.80; p = 0.10], myocardial infarction (MI) [RR = 0.84; p = 0.16], target lesion revascularization (TLR) [RR = 0.94; p = 0.68], and target vessel revascularization (TVR) [RR = 0.91; p = 0.52].

Conclusion

OCT-guided PCI led to an increased MSA and decreased cardiovascular mortality, stent thrombosis, stent malapposition, and major edge dissection. The incidence of all-cause mortality, MACE, MI, TLR, and TVR remained comparable across the two groups.

Intravascular imaging-guided coronary drug-eluting stent implantation: an updated network meta-analysis

BACKGROUND

Previous meta-analyses have shown reduced risks of composite adverse events with intravascular imaging-guided percutaneous coronary intervention (PCI) compared with angiography guidance alone. However, these studies have been insufficiently powered to show whether all-cause death or all myocardial infarction are reduced with intravascular imaging guidance, and most previous intravascular imaging studies were done with intravascular ultrasound rather than optical coherence tomography (OCT), a newer imaging modality. We aimed to assess the comparative performance of intravascular imaging-guided PCI and angiography-guided PCI with drug-eluting stents.

METHODS

For this systematic review and updated meta-analysis, we searched the MEDLINE, Embase, and Cochrane databases from inception to Aug 30, 2023, for studies that randomly assigned patients undergoing PCI with drug-eluting stents either to intravascular ultrasound or OCT, or both, or to angiography alone to guide the intervention. The searches were done and study-level data were extracted independently by two investigators. The primary endpoint was target lesion failure, defined as the composite of cardiac death, target vessel-myocardial infarction (TV-MI), or target lesion revascularisation, assessed in patients randomly assigned to intravascular imaging guidance (intravascular ultrasound or OCT) versus angiography guidance. We did a standard frequentist meta-analysis to generate direct data, and a network meta-analysis to generate indirect data and overall treatment effects. Outcomes were expressed as relative risks (RRs) with 95% CIs at the longest reported follow-up duration. This study was registered with the international prospective register of systematic reviews (PROSPERO, number CRD42023455662).

FINDINGS

22 trials were identified in which 15 964 patients were randomised and followed for a weighted mean duration of 24·7 months (longest duration of follow-up in each study ranging from 6 to 60 months). Compared with angiography-guided PCI, intravascular imaging-guided PCI resulted in a decreased risk of target lesion failure (RR 0·71 [95% CI 0·63-0·80]; p<0·0001), driven by reductions in the risks of cardiac death (RR 0·55 [95% CI 0·41-0·75]; p=0·0001), TV-MI (RR 0·82 [95% CI 0·68-0·98]; p=0·030), and target lesion revascularisation (RR 0·72 [95% CI 0·60-0·86]; p=0·0002). Intravascular imaging guidance also reduced the risks of stent thrombosis (RR 0·52 [95% CI 0·34-0·81]; p=0·0036), all myocardial infarction (RR 0·83 [95% CI 0·71-0·99]; p=0·033), and all-cause death (RR 0·75 [95% CI 0·60-0·93]; p=0·0091). Outcomes were similar for OCT-guided and intravascular ultrasound-guided PCI.

INTERPRETATION

Compared with angiography guidance, intravascular imaging guidance of coronary stent implantation with OCT or intravascular ultrasound enhances both the safety and effectiveness of PCI, reducing the risks of death, myocardial infarction, repeat revascularisation, and stent thrombosis.

FUNDING

Abbott.

High platelet reactivity strongly predicts early stent thrombosis in patients with drug-eluting stent implantation

Stent thrombosis (ST) is a fatal complication after percutaneous coronary intervention (PCI). The association between P2Y12 reaction unit (PRU) level and stent thrombosis occurrence remains unclear. Based on the multicenter, observational PTRG-DES (Platelet function and genoType-Related long-term proGnosis in DES-treated patients) registry of patients with drug-eluting stents (DES) implantation, a total of 11,714 patients with PRU values were analyzed. We sought to identify the predictors of early stent thrombosis (EST) and compared the primary outcome, a composite of cardiac death, myocardial infarction, and revascularization, between EST and non-EST groups. EST, defined as definite ST within 1 month after index PCI, occurred in 51 patients. PRU values were significantly higher in the EST group (263.5 ± 70.8 vs. 217.5 ± 78.7, p < 0.001). In multivariable analysis, PRU ≥ 252 (OR, 5.10; 95% CI 1.58-16.46; p = 0.006) and aspirin reaction unit ≥ 414 (OR 4.85; 95% CI 1.07-21.97; p = 0.040) were independent predictors of EST. The cumulative incidence of primary composite outcome at one year was significantly higher in the EST group (38.2% vs. 3.9%, Log-rank p < 0.001). In patients treated with clopidogrel after successful DES implantation, EST was associated with higher platelet reactivities, and a greater risk of cardiovascular events.Trial Registration: clinicaltrials.gov Identifier: NCT04734028.

Optical Coherence Tomography-Guided versus Angiography-Guided PCI

BACKGROUND

Data regarding clinical outcomes after optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) as compared with angiography-guided PCI are limited.

METHODS

In this prospective, randomized, single-blind trial, we randomly assigned patients with medication-treated diabetes or complex coronary-artery lesions to undergo OCT-guided PCI or angiography-guided PCI. A final blinded OCT procedure was performed in patients in the angiography group. The two primary efficacy end points were the minimum stent area after PCI as assessed with OCT and target-vessel failure at 2 years, defined as a composite of death from cardiac causes, target-vessel myocardial infarction, or ischemia-driven target-vessel revascularization. Safety was also assessed.

RESULTS

The trial was conducted at 80 sites in 18 countries. A total of 2487 patients underwent randomization: 1233 patients were assigned to undergo OCT-guided PCI, and 1254 to undergo angiography-guided PCI. The minimum stent area after PCI was 5.72±2.04 mm2 in the OCT group and 5.36±1.87 mm2 in the angiography group (mean difference, 0.36 mm2; 95% confidence interval [CI], 0.21 to 0.51; P<0.001). Target-vessel failure within 2 years occurred in 88 patients in the OCT group and in 99 patients in the angiography group (Kaplan-Meier estimates, 7.4% and 8.2%, respectively; hazard ratio, 0.90; 95% CI, 0.67 to 1.19; P = 0.45). OCT-related adverse events occurred in 1 patient in the OCT group and in 2 patients in the angiography group. Stent thrombosis within 2 years occurred in 6 patients (0.5%) in the OCT group and in 17 patients (1.4%) in the angiography group.

CONCLUSIONS

Among patients undergoing PCI, OCT guidance resulted in a larger minimum stent area than angiography guidance, but there was no apparent between-group difference in the percentage of patients with target-vessel failure at 2 years. (Funded by Abbott; ILUMIEN IV: OPTIMAL PCI ClinicalTrials.gov number, NCT03507777.).

Identifying the Incidence, Predictors, Outcomes, and Prevention of Stent Thrombosis (ST) in Post-percutaneous Coronary Revascularization Patients With Drug-Eluting Stents (DES): A Systematic Review

Stent thrombosis (ST) is a rare but catastrophic event to happen to a stented coronary artery. The incidence of ST has greatly been reduced after the advent of modern drug-eluting stent (DES) implants, which have become the most preferred treatment option in the stenting category for coronary artery disease (CAD). Although the risk reduction by newer category implant provides substantial benefits, the possibility of thrombosis still exists mostly during the early stage of DES implantation. The development of ST after percutaneous coronary intervention (PCI) can be predicted by multiple factors, but advancements in early diagnostic techniques and modified stent types have greatly reduced the occurrence of this complication. Mortality, which is one of the complications of ST, is primarily influenced by patient-related factors such as incomplete treatment duration of dual antiplatelet therapy (DAPT). The duration of DAPT after DES implantation in patients with acute coronary syndrome (ACS) is determined based on individual characteristics, mainly considered in view of bleeding or ischemia risk. Risk evaluation systems like DAPT/precise-DAPT scores help tailor and personalize the duration of DAPT for each individual patient. This systematic review contains pertinent articles extracted from the PubMed database. We retrieved articles from various study categories, encompassing publications from the period spanning 2014 to 2022. Our analysis highlighted results from studies investigating different aspects contributing to ST development. The most favorable prevention option was the use of customized DAPT intervention based on patient-specific predictable factors. Several complications associated with ST were identified, including recurrent ST, major adverse cardiovascular events (MACE) encompassing all-cause mortality (including cardiac and non-cardiac mortality), cerebrovascular accidents (CVA) or transient ischemic attacks (TIA), hospitalization due to heart failure, and myocardial infarction requiring revascularization. Mortality was also observed as a significant outcome. The umbrella term of ST includes multiple causative factors. Although DES has improved patient survival rates vastly with its usage, careful risk factor assessment and required follow-up, in each individual being stented, further guarantee a more promising reduction in late adverse outcomes.

Biomedical Applications of Electrets: Recent Advance and Future Perspectives

Recently, electrical stimulation, as a non-pharmacological physical stimulus, has been widely exploited in biomedical and clinical applications due to its ability to significantly enhance cell proliferation and differentiation. As a kind of dielectric material with permanent polarization characteristics, electrets have demonstrated tremendous potential in this field owing to their merits of low cost, stable performance, and excellent biocompatibility. This review provides a comprehensive summary of the recent advances in electrets and their biomedical applications. We first provide a brief introduction to the development of electrets, as well as typical materials and fabrication methods. Subsequently, we systematically describe the recent advances of electrets in biomedical applications, including bone regeneration, wound healing, nerve regeneration, drug delivery, and wearable electronics. Finally, the present challenges and opportunities have also been discussed in this emerging field. This review is anticipated to provide state-of-the-art insights on the electrical stimulation-related applications of electrets.

Management of failed stenting of the unprotected left main coronary artery

Percutaneous coronary intervention (PCI) is increasingly accepted as treatment for unprotected left main coronary artery (ULMCA) disease especially in those patients who are unsuitable for cardiac surgery. Treatment of any stent failure is associated with increased complexity and worse clinical outcomes when compared with de novo lesion revascularization. Intracoronary imaging has provided new insight into mechanisms of stent failure and treatment options have developed considerably over the last decade. There is paucity of evidence on the management strategy for stent failure in the specific setting of ULMCA. Treating any left main with PCI requires careful consideration and consequently treatment of failed stents in ULMCA is complex and provides unique challenges. Consequently, we provide an overview of ULMCA stent failure, proposing a tailored algorithm to guide best management and decision in daily clinical practice, with a special focus on intracoronary imaging characterization of causal mechanisms and specific technical and procedural considerations.

Metal free percutaneous coronary interventions in all-comers: First experience with a novel sirolimus-coated balloon

BACKGROUND

Limus-eluting stents have become the mainstay for percutaneous coronary intervention (PCI). However, even with the latest generation drug-eluting stent, in-stent restenosis and very late stent thrombosis remain a concern. The Selution SLR™ drug-coated balloon (DCB) is a novel sirolimus-coated balloon that provides a controlled release of the antiproliferative drug. Herein we evaluated its performance in a real-world patient cohort with complex coronary artery lesions.

METHODS

Patients undergoing PCI using the Selution SLR™ DCB were analyzed from the prospective SIROOP registry. We evaluated procedural success and clinical outcomes, including major adverse cardiovascular event (MACE), cardiac death, target vessel myocardial infarction and target lesion revascularization.

RESULTS

From September 2020 to April 2021, we enrolled 78 patients (87 lesions) treated using a "DCB only" strategy. The mean age was 66.7 ± 10.4 years and 28 (36%) presented with an acute coronary syndrome. Almost all lesions were type B2/C 86 (99%) and 49 (63%) had moderate to severe calcifications. Procedural success was 100%. After a median follow-up of 11.2 months (interquartile range: 10.0-12.6), MACE occurred in 5 (6.8%) patients. No acute vessel closure was observed.

CONCLUSIONS

In complex coronary lesions, a "DCB only" strategy using the Selution SLR™ DCB is not just safe and feasible, but also seems to be associated with a low rate of MACE at 1-year follow-up. Our promising results warrant further evaluation in a dedicated comparative trial.