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The use of two types of bulky cations, tetrabutylammonium (TBA+) and Cs+, as electrolyte additives in Na‐O2 batteries is investigated. These cations facilitate the stabilization of sodium superoxide in the electrolyte, promoting the solution‐mediated pathway. Both the addition of TBA+ and Cs+ favor the growth of larger NaO2 cubes than in the case of the electrolyte containing only sodium salt, particularly in the case of Cs+. In terms of full discharge capacity, both additives lead to an increase in the discharge capacity, which is greater in Cs+ (50% enhancement). TBA+ also provides an improved stabilization of superoxide; nevertheless, the interaction is not as strong as in the case of Cs+ due to the steric hindrance set by the alkyl groups. The presence of these additives not only affects the NaO2 formation mechanism, but also influences the nature of the solid electrolyte interphase. The presence of Cs+ generates a more stable solid‐electrolyte interphase, which increases the cycle life of Na‐O2 batteries. Overall, new insights are provided to control the growth of the discharge products, modify the oxygen reduction reaction mechanism, and protect the Na metal anode surface by adding bulky monovalent cations in the electrolyte formulation. [ABSTRACT FROM AUTHOR]

Interventionalists encounter widely different coronary anatomies during left main coronary artery stenting. Optimal percutaneous coronary intervention in left main disease necessitates stents that achieve adequate apposition and adapt to frequently disparate diameters in the same lesion, without the need for overexpansion. Until recently, stent designs have hampered the treatment of very large lesions in left main arteries. Postdilation of the stents beyond their recommended diameters can cause restenosis, thrombosis, or arterial dissection. We report successful angiographic outcomes after our deployment of different stents in 3 patients, present our rationale for choosing each stent, and discuss considerations that influence the percutaneous treatment of severe left main disease. [ABSTRACT FROM AUTHOR]

Although drug-eluting stents have reduced the restenosis rate, some patients are not good candidates for prolonged double-antiplatelet therapy. Our goal was to learn the results of implanting cobalt-chromium stents in long lesions of large vessels. All consecutive patients with ≥1 lesion treated with a cobalt-chromium stent ≥28 mmrestenosis in length and ≥3.5 mm in diameter during a 12-month period in 2 centers were monitored clinically and angiographically to determine the clinical status, restenosis rate, pattern of restenosis, and need for revascularization. The series comprised 78 patients with 81 lesions, mean age, 62.6 ± 15.2 yr; diabetes mellitus,19.2%; and primary or rescue intervention, 20.6%. Target vessels were the left anterior descending coronary artery, 12 (14.8%); left circumflex coronary artery, 12 (14.8%); and right coronary artery, 57 (70.4%). The mean lesion length was 35.18 ± 12.65 mm. The proximal reference diameter after percutaneous coronary intervention was 3.64 ± 0.54 mm; the distal, 3.2 ± 0.43 mm; and the mean, 3.42 ± 0.44 mm. The mean stent length was 38.05 ± 12.78 mm (range, 28-90 mm). The binary restenosis rate was 23% (15/64), with pattern IB in 2 cases, IC in 5, II in 7, and IV in 1. Revascularization was needed in 6 patients. In treating long lesions of large vessels, we found that cobalt-chromium stents achieved a moderate rate of target-vessel restenosis and a low rate of repeat revascularization. The pattern of restenosis was focal in almost half of the cases, and, in most remaining cases, restenosis affected short segments of the vessel. [ABSTRACT FROM AUTHOR]

The Food and Drug Administration and the European Medicines Agency sent a warning in 2010 discouraging the concomitant use of clopidogrel with omeprazole or esomeprazole. The purpose is to know the gastroprotective approach in patients with acute coronary syndrome (ACS) and the level of follow-up of the alert. In 17 hospitals with catheterization laboratory in Spain, 1 per region, we studied 25 consecutive patients per hospital whose diagnosis of discharge since October 1, 2013, had been any type of ACS. We analyzed their baseline clinical profile, the gatroprotective agents at admission and discharge and the antiplatelet therapy at discharge. The number of patients included was 425: age 67.2 ± 12.5 years, women 29.8%, diabetes 36.5%. The patients presented unstable angina in 21.6%, non-ST-elevation myocardial infarction in 35.3% and ST-elevation myocardial infarction in 43.1%. Conservative approach was chosen in 17.9%, bare-metal stents 32.2%, ≥ 1 drug-eluting stent 48.5%, and surgery 1.4%. Aspirin was indicated in 1.9%, aspirin + clopidogrel 73.6%, aspirin + prasugrel 17.6%, and aspririn + ticagrelor 6.8%. Gastroprotective agents were present in 40.2% patients at admission and this percentage increased to 93.7% at discharge. Of the 313 (73.6%) on clopidogrel in 96 (30.6%) was combined with omeprazole and 3 (0.95%) with esomeprazole, whereas the most commonly used was pantoprazole with 190 patients (44.7%). In conclusion, almost the totality of the patients with an ACS receive gastroprotective agents at the moment of discharge, most of them with proton-pump inhibitors. In one every 3 cases of the patients who are on clopidogrel, the recommendation of the Food and Drug Administration and the European Medicines Agency is not followed. [ABSTRACT FROM AUTHOR]

The presence of singlet oxygen in metal-O 2 batteries is one of the major factors responsible for the degradation of the electrolyte. The formation of singlet oxygen, 1O 2 , at Na O 2 cathodes in sodium trifluoromethane sulfonate (NaOTf)-diglyme electrolyte has been detected in-operando by fluorescence quenching of 9,10-dimethylanthracene, DMA, a specific chemical monitor of singlet oxygen. Furthermore, ammonium Brönsted acid protonates superoxide and the further disproportionation of HO 2 results in a catalytic EC' mechanism that recycles oxygen, a fraction of which has been found to be 1O 2. Unlike, ammonium trifluoromethane sulfonate (NH 4 OTf), in tetrabutylammonium trifluoromethane sulfonate (TBAOTf), which lacks acidic protons, superoxide is stabilized by the large cation and no 1O 2 could be detected. The addition of sodium azide to the electrolyte, an efficient specific physical quencher of singlet oxygen, results in negligible detection of this harmful oxygen reduction intermediate and proves the nature of 1O 2. [ABSTRACT FROM AUTHOR]

A response by Erik Lerkevang Grove and colleagues to a letter to the editor about their article "Aspirin and coronary artery disease" is presented.

Abstract: Coronary artery obstruction during cardiac catheterization is rare. It is a serious complication and has been reported to occur in 0.15 to 0.5% of cases. Thromboembolism, air embolism and coronary dissection have been described as the most common causes of intraprocedural coronary occlusion. Aortic valve masses can also cause coronary obstruction. We report the case of a young woman with a complication and an incidental finding during angiographic procedure. A surgical treatment was needed. [Copyright &y& Elsevier]

Revascularization of left main coronary artery (LMCA) stenosis is mostly based on angiography. Indices based on angiography might increase accuracy of the decision, although they have been scarcely used in LMCA. The objective of this study is to study the diagnostic agreement of QFR (quantitative flow ratio) with wire-based fractional flow reserve (FFR) in LMCA lesions and to compare with visual severity assessment. In a series of patients with invasive FFR assessment of intermediate LMCA stenoses we retrospectively compared the measured value of QFR with that of FFR and the estimate of significance from angiography. 107 QFR studies were included. The QFR intra-observer and inter-observer agreement was 87% and 82% respectively. The mean QFR-FFR difference was 0.047 ± 0.05 with a concordance of 90.7%, sensitivity 88.1%, specificity 92.3%, positive predictive value 88.1% and negative predictive value 92.3%. All these values were superior to those observed with the visual estimation which showed an intra- and inter-observer agreement of 73% and 72% respectively, besides 78% with the FFR value. The low diagnostic performance of the visual estimation and the acceptable performance of the QFR index measurement were observed in all subgroups analysed. QFR allows an acceptable estimate of the FFR obtained with intracoronary pressure guidewire in intermediate LMCA lesions, and clearly superior to the assessment based on angiography alone. The decision to revascularize patients with moderate LMCA lesions should not be based solely on the degree of angiographic stenosis. [Display omitted] • In LMCA the estimation of its functional impact based exclusively on angiography has a low reproducibility and agreement with the FFR. • The decision based exclusively on the visual estimation of angiography can result in inadequate treatment of a lesion in the left main coronary artery. • The use of functional indices based on angiography may be a precise and objective tool for decision making without the need of invasive procedures using pressure wire. [ABSTRACT FROM AUTHOR]

We sought to investigate the antithrombotic regimens applied and their prognostic effects in patients over 75 years old with atrial fibrillation (AF) after revascularization with drug-eluting stents (DES). Retrospective registry in 20 centers including patients over 75 years with AF treated with DES. A primary endpoint of MACCE and a co-primary endpoint of major bleeding by ISTH criteria were considered at 12 months. A total of 1249 patients (81.1 ± 4.2 years, 33.1% women, 66.6% ACS, 30.6% complex PCI) were included. Triple antithrombotic therapy (TAT) was prescribed in 81.7% and dual antithrombotic therapy (DAT) in 18.3%. TAT was based on direct oral anticoagulants (DOAC) in 48.4% and maintained for only 1 month in 52.2%, and DAT included DOAC in 70.6%. Primary endpoint of MACCE was met in 9.6% and primary endpoint of major bleeding in 9.4%. TAT was significantly associated with more bleeding (10.2% vs. 6.1%, p = 0.04) but less MACCE (8.7% vs. 13.6%, p = 0.02) than DAT and the use of DOAC was significantly associated to less bleeding (8% vs. 11.1%, p = 0.03) and similar MACCE (9.8% vs. 9.4%, p = 0.8). TAT over 1 month or with VKA was associated with more major bleeding but comparable MACCE rates. Despite advanced age TAT prevails, but duration over 1 month or the use of other agent than Apixaban are associated with increased bleeding without additional MACCE prevention. DAT reduces bleeding but with a trade-off in terms of ischemic events. DOAC use was significantly associated to less bleeding and similar MACCE rates. • Evidence regarding combination of antithrombotic agents in elderly patients with AF undergoing DES implantation is scarce. • Randomized trials focused on elderly patients are hardly foreseeable, so large registries are required to enhance knowledge. • This large multicenter registry provides valuable insights into the contemporary practice in this complex scenario. • Triple strategy dominates, but beyond 1 month or without Apixaban bleeding was increased without additional MACCE prevention. • Double therapy reduces risk of bleeding but with a trade-off in terms of ischemic cardiac events in a high-risk population. [ABSTRACT FROM AUTHOR]

Background: The safety and feasibility of ambulatory PCI has been demonstrated in selected patients with "simple" lesions, but it is not well known whether it could be applied in more "complex" scenarios.Methods: Main objective is to assess the feasibility and safety of ambulatory complex PCI. Prospective multicentre registry of 1047 consecutive patients planned for ambulatory trans-radial PCI. Outcomes in patients with "complex angioplasty" (CA group: 313 (30%)) were analysed and compared with those of "simple angioplasty" (SA group: 734, 70%). The feasibility (% of patients finally discharged) and safety (MACE at 24 h and at 1 month) were compared between groups. We also analyse admissions, visits to the emergency department and minor vascular complications.Results: Feasibility was higher for SA (80.6% vs. 63.6%, OR 1.89, 95% CI 1.52-2.35, p < 0.001). Ambulatory PCI was very safe in both groups. In CA no MACE occurred at 24 h (vs. 0.17% SA) or 30 days (vs. 0.68% in SA). There were also no differences in re-admissions, visits to the emergency department or minor vascular complications (there was a non-significant tendency to higher rate of radial occlusion at 1 month in the CA group, 5.5% vs. 2.7%, p: 0.07).Conclusions: The feasibility of ambulatory PCI in selected patients with complex lesions is lower than in simple lesions, however when it is possible, it is as safe as in selected patients with simple lesions. [ABSTRACT FROM AUTHOR]

Sodium-oxygen batteries are becoming of increasing interest in the research community as they are able to overcome some of the difficulties associated with lithium-oxygen batteries. The interpretation of the processes governing the discharge and charge of these batteries, however, has been under debate since their early development. In this work we combine different electrochemical methods to build up a model of the discharge product formation and decomposition. We initially analyze the formation and decomposition of the discharge products by means of electrochemical impedance spectroscopy. After that, and for the first time, oxygen electrode processes in Na-O 2 cells are analyzed by means of electrochemical quartz crystal microbalance experiments. Based on the combination of these two techniques it is possible to evidence the stabilization of the discharge products in the electrolyte prior to their precipitation. The deposition of passivating products that cannot be stripped off during charge is also demonstrated. Cyclic voltammetry experiments at different potential limits further confirm these passivation reactions. In conclusion, this work provides an accurate picture of the mechanism of the Na-O 2 cell reactions by combining different electrochemical techniques. [ABSTRACT FROM AUTHOR]

Objectives: This study is a prospective validation of 6 mm2 as a minimum lumen area (MLA) cutoff value for revascularization of left main coronary artery (LMCA) lesions. Background: Lesions involving the LMCA are prognostically relevant. Angiography has important limitations in the evaluation of LMCA lesions with intermediate severity. An MLA of 6 mm2 assessed by intravascular ultrasound has been proposed as a cutoff value to determine lesion severity, but there are no large studies evaluating the prospective application and safety of this approach. Methods: We have designed a multicenter, prospective study. Consecutive patients with intermediate lesions in unprotected LMCA were evaluated with intravascular ultrasound. An MLA <6 mm2 was used as criterion for revascularization. Results: A total of 354 patients were included in 22 centers. LMCA revascularization was performed in 90.5% (152 of 168) of patients with an MLA <6 mm2 and was deferred in 96% (179 of 186) of patients with an MLA of 6 mm2 or more. A large scatter was observed between both groups regarding angiographic parameters. In a 2-year follow-up period, cardiac death-free survival was 97.7% in the deferred group versus 94.5% in the revascularized group (p = 0.5), and event-free survival was 87.3% versus 80.6%, respectively (p = 0.3). In the 2-year period, only 8 (4.4%) patients in the deferred group required subsequent LMCA revascularization, none with an infarction. Conclusions: Angiographic measurements are not reliable in the assessment of intermediate LMCA lesions. An MLA of 6 mm2 or more is a safe value for deferring revascularization of the LMCA, given the application of the clinical and angiographic inclusion criteria used in this study. [Copyright &y& Elsevier]

Abstract: The main objective of this research was to define the association between common mitochondrial DNA (mtDNA) polymorphisms and mitochondrial transcription A gene (TFAM) variants and myocardial infarction (MI) in patients with atherosclerotic diseased vessels. Ten mitochondrial polymorphisms that defined the nine common European haplogroups were genotyped in 500 male patients with early onset MI (<55years) and at least one atherosclerotic coronary vessel (angiographically confirmed), and 500 healthy controls. In addition, we searched for DNA variants in the coding region of the TFAM gene and compared patients and controls for the allele and genotype frequencies. Early onset MI was strongly associated with male gender and tobacco smoking in our population. MtDNA haplogroup H (defined by allele 7028°C) was significantly more frequent in a first group of patients (n =250) compared to controls (n =300), and the association was confirmed in a second group of only smokers (250 patients and 200 controls). For total patients and controls, we obtained a p =0.002 (OR=1.50; 95% CI=1.17–1.92) for H vs. the other haplogroups. We found four common TFAM polymorphisms, with allele/genotype frequencies that did not differ between patients and controls. In conclusion, mitochondrial haplogroup H was associated with early onset MI in male smokers. Our work supported a role for the mtDNA variation in the risk for atherosclerosis and ischemic associated events, likely due to differences in mitochondrial function and reactive oxygen production between the different haplogroups. [ABSTRACT FROM AUTHOR]

Objectives: This study sought to assess the incidence, predictors, and outcome of drug-eluting stent(DES) thrombosis in real-world clinical practice. Background: The DES thromboses in randomized trials could not be comparable to those observed in clinical practice, frequently including off-label indications. Methods: We designed a large-scale, nonindustry-linked multicentered registry, with 20 centers in Spain. The participant centers provided follow-up data for their patients treated with DES, reporting a detailed standardized form in the event of any angiography-documented DES-associated thrombosis occurring. Results: Of 23,500 patients treated with DES, definite stent thrombosis(ST) developed in 301: 24 acute, 125 subacute, and 152 late. Of the late, 62 occurred >1 year(very late ST). The cumulative incidence was 2% at 3 years. Antiplatelet treatment had been discontinued in 95 cases(31.6%). No differences in incidences were found among stent types. Independent predictors for subacute ST analyzed in a subgroup of 14,120 cases were diabetes, renal failure, acute coronary syndrome, ST-segment elevation myocardial infarction, stent length, and left anterior descending artery stenting, and for late ST were ST-segment elevation myocardial infarction, stenting in left anterior descending artery, and stent length. Mortality at 1-year follow-up was 16% and ST recurrence 4.6%. Older age, left ventricular ejection fraction <45%, nonrestoration of Thrombolysis In Myocardial Infarction flow grade 3, and additional stenting were independent predictors for mortality. Conclusions: The cumulative incidence of ST after DES implantation was 2% at 3 years. No differences were found among stent types. Patient profiles differed between early and late ST. Short-term prognosis is poor, especially when restoration of normal flow fails. [Copyright &y& Elsevier]

Abnormal glucose regulation (AGR) has serious prognostic implications in patients with coronary artery disease (CAD). However there are no records about patients undergoing percutaneous coronary intervention (PCI), for whom the diagnosis of diabetes (known and unknown) may suppose a therapeutical implication of proved benefit (use of IIb/IIIa receptor blockers and drug-eluted stents). Our aim is to assess the current prevalence of abnormal glucose regulation in the patients referred to for percutaneous coronary intervention (PCI) at University Hospital in Asturias, north of Spain. Prospective study. Patients with PCI for ST elevation myocardial infarction (STEMI) are excluded. Those without previous known diabetes undergo a 75-g oral glucose tolerance test (OGTT) 15 days after discharge. We use the WHO (1999) criteria based upon the measurement at FPG and 2 h after glucose intake. Data on 662 successive patients referred to PCI were collected over a period of 7 months. Eighty-two patients were excluded from the study (STEMI), leaving a total of 580 patient population. 167 patients were not studied due to previous known diabetes (28,8%), 75 out of 413 patients without previous diabetes were excluded due to different causes and 338 underwent the OGTT. Population profile: average age 64,9 years, males 79,9%, active smokers 28,3%, hypertension 49,7%, dyslipidemia 48,5%, BMI>30 Kg/m²:35, 7%, previous MI 37,2%, previous revascularization 15,1%, peripheral vascular disease 15,7%, PCI indication (stable angina 23,6%, UA/NSTEMI 76,4%). The results were: known diabetes 28,8%, unknown diabetes after OGTT: 16,2%, IGT: 24,5%, IFG: 1%, normoglycemia 29,5%. Among patients referred to PCI: a) 70,5% present some alterations in hydro carbonate metabolism, b) patients without previous known diabetes exhibited an anomalous OGTT in 57% cases (22% unknown diabetes mellitus). In this population, the OGTT has proved invaluable results to identify a large subset of high-risk patients in which secondary preventive and therapeutic measures should be initiated soon. [ABSTRACT FROM AUTHOR]

The article focuses on the findings of a population-based cross-sectional study that compared the effectivity of oral glucose tolerance test (OGTT) with fasting plasma glucose (FPG) in diagnosing unknown diabetes in patients with coronary artery disease (CAD), conducted in Spain. An OGTT was administered based on the recommendations from the World Health Organization (WHO). The study found that the OGTT is 4 times more likely to diagnose unknown diabetes compared to the FPG.

Abstract: Endovascular treatment of thoracic aortic pathology has become a valuable alternative therapeutic option to open surgery, however complications both during implantation and the postoperative period may occur. In this case report we present an intimal dehiscence during endovascular procedure. Diagnosis was made by transoesophageal echocardiography. [Copyright &y& Elsevier]