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Atherosclerotic plaques that lead to acute coronary syndromes often occur at sites of angiographically mild coronary-artery stenosis. Lesion-related risk factors for such events are poorly understood.In a prospective study, 697 patients with acute coronary syndromes underwent three-vessel coronary angiography and gray-scale and radiofrequency intravascular ultrasonographic imaging after percutaneous coronary intervention. Subsequent major adverse cardiovascular events (death from cardiac causes, cardiac arrest, myocardial infarction, or rehospitalization due to unstable or progressive angina) were adjudicated to be related to either originally treated (culprit) lesions or untreated (nonculprit) lesions. The median follow-up period was 3.4 years.The 3-year cumulative rate of major adverse cardiovascular events was 20.4%. Events were adjudicated to be related to culprit lesions in 12.9% of patients and to nonculprit lesions in 11.6%. Most nonculprit lesions responsible for follow-up events were angiographically mild at baseline (mean [±SD] diameter stenosis, 32.3±20.6%). However, on multivariate analysis, nonculprit lesions associated with recurrent events were more likely than those not associated with recurrent events to be characterized by a plaque burden of 70% or greater (hazard ratio, 5.03; 95% confidence interval [CI], 2.51 to 10.11; P<0.001) or a minimal luminal area of 4.0 mm(2) or less (hazard ratio, 3.21; 95% CI, 1.61 to 6.42; P=0.001) or to be classified on the basis of radiofrequency intravascular ultrasonography as thin-cap fibroatheromas (hazard ratio, 3.35; 95% CI, 1.77 to 6.36; P<0.001).In patients who presented with an acute coronary syndrome and underwent percutaneous coronary intervention, major adverse cardiovascular events occurring during follow-up were equally attributable to recurrence at the site of culprit lesions and to nonculprit lesions. Although nonculprit lesions that were responsible for unanticipated events were frequently angiographically mild, most were thin-cap fibroatheromas or were characterized by a large plaque burden, a small luminal area, or some combination of these characteristics, as determined by gray-scale and radiofrequency intravascular ultrasonography. (Funded by Abbott Vascular and Volcano; ClinicalTrials.gov number, NCT00180466.).

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• Ductile fracture tests on WAAM steel specimens covering various stress states. • Superior fracture ductility compared to equivalent, conventional steels observed. • Development and validation of numerical models for WAAM fracture specimens. • Calibrated fracture models provide accurate predictions for WAAM steel plates. Utilising robotic welding technology, wire arc additive manufacturing (WAAM) is developing into a viable method for the production of structural steel elements. However, there remains a lack of knowledge on the fracture ductility of WAAM steels, which is of particular importance under extreme loading conditions, such as severe earthquakes. An experimental and numerical study into the ductile fracture behaviour of WAAM ER70S-6 carbon steel plates has therefore been undertaken and is reported herein. ER70S-6 steel was selected for this study for its widespread use in WAAM and its well-characterised and desirable mechanical properties, facilitating comparisons of fracture ductility with conventionally-produced steels. Following mechanical and microstructural characterisation, a series of WAAM fracture specimens of two thicknesses and various shapes (corresponding to various stress states) was tested under quasi-static tensile loading. Digital image correlation (DIC) was employed to monitor the evolution of the deformations and strains of the specimens during testing. The WAAM steel exhibited superior fracture ductility compared to equivalent, conventionally-produced steels, with the thicker material showing higher ductility than the thinner material. Finite element (FE) models of the fracture specimens were developed and validated, with good agreement between the simulated and measured load-displacement curves and strain fields demonstrated. Through the experiments and simulations, the equivalent plastic strain at fracture and the corresponding stress triaxiality and Lode angle parameter were determined for each specimen. The obtained fracture data were used to calibrate three typical ductile fracture models – the Modified Mohr-Coulomb (MMC), Hosford-Coulomb (H-C) and Lou-Huh (L-H) models. All the models were shown to provide accurate predictions of fracture initiation for the WAAM ER70S-6 steel. The calibrated fracture loci represent a step forward for the prediction of ductile fracture in WAAM steels.

Background Currently available randomized data on the comparison between percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) for the treatment of unprotected left main coronary disease (LMD) lacks statistical power due to low numbers of patients enrolled. Objectives This study assessed long-term outcomes of PCI and CABG for the treatment of LMD in specific subgroups according to disease anatomic complexity. Methods We conducted a pooled analysis of individual patient-level data of the LMD patients included in the PRECOMBAT (Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease) and SYNTAX (Synergy Between PCI With TAXUS and Cardiac Surgery) trials. Incidences of major adverse cardiac events were assessed at 5 years follow-up. Results Study population comprised 1,305 patients. The incidence of major adverse cardiac and cerebrovascular events at 5 years was 28.3% in the PCI group and 23.0% in the CABG group (hazard ratio [HR]: 1.23; 95% confidence interval [CI]: 1.01 to 1.55; p = 0.045). This difference is mainly driven by a higher rate of repeat revascularization associated with PCI (HR: 1.85; 95% CI: 1.38 to 2.47; p < 0.001). The 2 strategies showed similar rates of the safety composite endpoint of death, myocardial infarction, or stroke (p = 0.45). In patients with isolated LM or LM + 1-vessel disease, PCI was associated with a 60% reduction in all-cause mortality (HR: 0.40; 95% CI: 0.20 to 0.83; p = 0.029) and 67% reduction in cardiac mortality (HR: 0.33; 95% CI: 0.12 to 0.88; p = 0.025) when compared with CABG. Conclusions In patients with unprotected LMD, CABG, and PCI result in similar rates of the safety composite endpoint of death, myocardial infarction, or stroke. In patients with isolated LM or LM + 1-vessel disease, PCI is associated with lower all-cause and cardiac mortality when compared to CABG.

The efficacy and safety of continued bivalirudin infusion after percutaneous coronary intervention (PCI) remains uncertain. We sought to investigate the association between post-PCI bivalirudin infusion and the risk of net adverse clinical events (NACE) at 30 days.In the GLOBAL LEADERS study, all patients who received bivalirudin during PCI were categorized according to the use of bivalirudin infusion after the procedure. The primary endpoint of the present analysis was NACE [a composite of all-cause death, any stroke, any myocardial infarction, all revascularization, and bleeding assessed according to the Bleeding Academic Research Consortium (BARC) criteria Type 3 or 5] at 30 days. The key safety endpoint was BARC Type 3 or 5 bleeding and definite stent thrombosis. Of 15 968 patients, 13 870 underwent PCI with the use of bivalirudin. In total, 7148 patients received continued bivalirudin infusion after procedure, while 6722 patients received standard care. After propensity score covariate adjustment, the risk of NACE did not significantly differ between two treatments after PCI [continued bivalirudin infusion vs. no bivalirudin infusion: 3.2% vs. 3.1%, adjusted hazard ratio (aHR) 1.35, 95% confidence interval (CI) 0.99-1.84, P = 0.06] nor the BARC Type 3 or 5 bleeding (0.7% vs. 0.7%, aHR 0.89, 95% CI 0.44-1.79; P = 0.743) and definite stent thrombosis (0.5% vs. 0.3%, aHR 1.71, 95% CI 0.77-3.81, P = 0.189). However, continued bivalirudin infusion was associated with an increased risk of NACE and definite stent thrombosis in ST-elevation myocardial infarction (STEMI) patients.In an all-comers population undergoing PCI, there was no significant difference in the risk of NACE at 30 days between continued bivalirudin infusion vs. no bivalirudin infusion after procedure but continued bivalirudin infusion was associated with a higher risk of NACE in STEMI patients when compared with no infusion.

Abstract Background Recent studies have shown deposition of immunoglobulin G4 (IgG4) and food proteins in the esophageal mucosa of eosinophilic esophagitis (EoE) patients. Our aims were to assess whether co‐localization of IgG4 and major cow's milk proteins (CMPs) was associated with EoE disease activity and to investigate the proteins enriched in proximity to IgG4 deposits. Methods This study included adult subjects with EoE ( n = 13) and non‐EoE controls ( n = 5). Esophageal biopsies were immunofluorescence stained for IgG4 and CMPs. Co‐localization in paired samples from active disease and remission was assessed and compared to controls. The proteome surrounding IgG4 deposits was evaluated by the novel technique, AutoSTOMP. IgG4‐food protein interactions were confirmed with co‐immunoprecipitation and mass spectrometry. Results IgG4‐CMP co‐localization was higher in the active EoE group compared to paired remission samples (Bos d 4, p = .02; Bos d 5, p = .002; Bos d 8, p = .002). Co‐localization was also significantly higher in the active EoE group compared to non‐EoE controls (Bos d 4, p = .0013; Bos d 5, p = .0007; Bos d 8, p = .0013). AutoSTOMP identified eosinophil‐derived proteins (PRG 2 and 3, EPX, RNASE3) and calpain‐14 in IgG4‐enriched areas. Co‐immunoprecipitation and mass spectrometry confirmed IgG4 binding to multiple food allergens. Conclusion These findings further contribute to the understanding of the interaction of IgG4 with food antigens as it relates to EoE disease activity. These data strongly suggest the immune complex formation of IgG4 and major cow's milk proteins. These immune complexes may have a potential role in the pathophysiology of EoE by contributing to eosinophil activation and disease progression.

Wire-arc directed energy deposition (DED), also known as wire-arc additive manufacturing (WAAM), is a metal 3D printing technique that is recognised for its high efficiency, cost-effectiveness, flexibility in build scales and suitability for the construction sector. However, there remains a lack of fundamental data on the structural performance of WAAM elements, especially regarding their fatigue behaviour. A comprehensive experimental study into the fatigue behaviour of WAAM steel plates has therefore been undertaken and is reported herein. Following geometric, mechanical and microstructural characterisation, a series of WAAM coupons was tested under uniaxial high-cycle fatigue loading. A total of 75 fatigue tests on both as-built and machined coupons, covering various stress ranges and stress ratios (R = 0.1, 0.2, 0.3 and 0.4), have been conducted. The local stress concentrations in the as-built coupons induced by their surface undulations have also been studied by numerical simulations. The fatigue test results were analysed using constant life diagrams (CLDs) and S-N (stress-life) diagrams, based on both nominal and local stresses. The CLDs revealed that the fatigue strength of the as-built WAAM steel was relatively insensitive to the different stress ratios. The S-N diagrams showed that the surface undulations resulted in a reduction of about 35% in the fatigue endurance limit for the as-built WAAM material relative to the machined material, and a reduction of about 60% in fatigue life under the same load level. The as-built and machined WAAM coupons were shown to exhibit similar fatigue behaviour to conventional steel butt welds and S355 structural steel plates, respectively. Preliminary nominal stress-based and local stress-based S-N curves were also proposed for the WAAM steel.

Coronary CT angiography (CCTA) demonstrated high diagnostic accuracy for detecting coronary artery disease (CAD) and a key role in the management of patients with low-to-intermediate pretest likelihood of CAD. However, the clinical information provided by this noninvasive method is still regarded insufficient in patients with diffuse and complex CAD and for planning percutaneous coronary intervention (PCI) and surgical revascularization procedures. On the other hand, technology advancements have recently shown to improve CCTA diagnostic accuracy in patients with diffuse and calcific stenoses. Moreover, stress CT myocardial perfusion imaging (CT-MPI) and fractional flow reserve derived from CCTA (CT-FFR) have been introduced in clinical practice as new tools for evaluating the functional relevance of coronary stenoses, with the possibility to overcome the main CCTA drawback, i.e. anatomical assessment only. The potential value of CCTA to plan and guide interventional procedures lies in the wide range of information it can provide: a) detailed evaluation of plaque extension, volume and composition; b) prediction of procedural success of CTO PCI using scores derived from CCTA; c) identification of coronary lesions requiring additional techniques (e.g., atherectomy and lithotripsy) to improve stent implantation success by assessing calcium score and calcific plaque distribution; d) assessment of CCTA-derived Syntax Score and Syntax Score II, which allows to select the mode of revascularization (PCI or CABG) in patients with complex and multivessel CAD. The aim of this Consensus Document is to review and discuss the available data supporting the role of CCTA, CT-FFR and stress CT-MPI in the preprocedural and possibly intraprocedural planning and guidance of myocardial revascularization interventions.