Aims We investigated the clinical features, predictors, and long‐term prognosis of pacing‐induced cardiomyopathy (PiCM). Methods and results From a retrospective analysis of 1418 consecutive pacemaker patients, 618 were found to have a preserved baseline left ventricular ejection fraction (LVEF), follow‐up echocardiographic data, and no history of heart failure (HF). PiCM was defined as a reduction in LVEF (< 50%) along with either (i) a ≥ 10% decrease in LVEF, or (ii) new‐onset regional wall motion abnormality unrelated to coronary artery disease. PiCM occurred in 87 of 618 patients (14.1%), with a decrease in mean LVEF from 60.5% to 40.1%. The median time to PiCM was 4.7 years. Baseline left bundle branch block, wider paced QRS duration (≥ 155 ms), and higher ventricular pacing percentage (≥ 86%) were identified as independent predictors of PiCM in multivariate logistic regression analysis. The risk of PiCM increased gradually with the number of identified predictors, becoming more significant in the presence of two or more predictors (P < 0.001). During the entire follow‐up (median 7.2 years), the risk of all‐cause death or HF admission was significantly higher in patients with PiCM compared to those without PiCM (38.3% vs. 54.0%, adjusted hazard ratio 2.93; 95% confidence interval 1.82–4.72; P < 0.001). Conclusion Pacing‐induced cardiomyopathy patients showed a worse long‐term prognosis than those without PiCM. Therefore, patients with multiple risk factors of PiCM should be monitored carefully even if their left ventricular systolic function is preserved initially. A timely upgrade to a biventricular or His‐bundle pacing device needs to be considered in patients with PiCM.

2Transition metal oxides have been extensively studied and utilized as efficient catalysts. However, the strongly correlated behavior which often results in intriguing emergent phenomena in these materials has been mostly overlooked in understanding the electrochemical activities. Here, we demonstrate a close correlation between the phase transitions and oxygen evolution reaction (OER) in a strongly correlated SrRuO3. By systematically introducing Ru-O vacancies into the singlecrystalline SrRuO3 epitaxial thin films, we induced phase transition in crystalline symmetry which resulted in corresponding modification in the electronic structure. The modified electronic structure significantly affect the electrochemical activities, so a 30% decrease in the overpotential for the OER activity was achieved. Our study suggests that a substantial enhancement in the OER activity can be realized even within single material systems, by rational design and engineering of their crystal and electronic structures. 3Transition metal oxides show promising chemical activities that can be applied in solid oxide fuel cells (SOFC), rechargeable batteries, catalytic converters, oxygen-separation membranes, and gas sensors. [1][2][3][4][5] Oxygen evolution reaction (OER, 4OH -→ O 2 + 2H 2 O + 4e -) is one of the most important steps in energy conversion and storage mechanisms, and is the efficiency-limiting process in electrolytic water splitting and metal-air batteries. 6,7 The ultimate goal of OER study is to develop low-cost, highly active, and stable catalysts. 8,9 Recently, perovskite oxides (ABO 3 ), such as Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3-δ , Pr 0.5 Ba 0.5 CoO 3-δ , and LaCoO 3 , have attracted much attention owing to their intrinsically high OER activity. [10][11][12] More interestingly, properties such as surface oxygen binding energy, number of outer shell electrons in the transition metal ion, electron occupancy of the e g orbitals, and the proximity of the oxygen p-band to the Fermi level, have been proposed as descriptors for OER activity. 10,11,13,14 Such approaches, however, have been mainly tested by comparing systems containing different transition metal elements.Unintentionally, such variations in the identity of the elements therein involve commensurate changes in the atomic structures, valence states, electric resistivities, crystalline surfaces, and the overall and specific electronic structures of the materials. Therefore, approaches based on simplified electronic structure may not apply to distinctive material systems, and more carefully controlled study, for example, one using a single-material system, is necessary to precisely understand the effect of the catalyst's electronic structure on the OER. 15In order to probe the link between electronic structure and catalytic activity within a singlematerial system, we exploit the strongly correlated behavior in complex oxides. In particular, the strong coupling among the degrees of freedom of the d-electrons, i.e., charge, spin, orbital, and lattice, in transition...

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C ardiovascular disease is the major cause of mortality in patients with type 2 diabetes mellitus.1 Although intensive therapy to lower glucose has consistently been reported to reduce microvascular complications of type 2 diabetes mellitus, 2,3 whether intensive glycemic control reduces macrovascular complications and improves clinical outcomes remains controversial. 4,5 Limited data are available regarding the effect of intensive glycemic control for secondary prevention in patients with established cardiovascular disease, especially in those undergoing percutaneous coronary intervention (PCI). The association between baseline glycosylated hemoglobin A (HbA1c) at the time of PCI and clinical outcomes among diabetic patients was reported in a few studies with conflicting results. 6,7 Moreover, it is not known if glycemic control after PCI can improve cardiovascular outcomes, which is a more important issue than glycemic status at the time of PCI. Because diabetic patients account for more than a quarter of all patients undergoing PCI and have worse outcomes compared with nondiabetic patients, 8,9 determining the optimal strategy for glycemic control in these patients after PCI has substantial clinical implications. Therefore, we investigated the association between glycemic status as estimated by HbA1c measured 2 years after PCI and long-term cardiovascular outcomes in type 2 diabetic patients undergoing PCI using drug-eluting stents (DES).Background-Data on the association between glycemic control after percutaneous coronary intervention and clinical outcomes are limited and controversial in diabetic patients. Methods and Results-We studied 980 patients with type 2 diabetes mellitus undergoing percutaneous coronary intervention using drug-eluting stents. Based on 2-year glycosylated hemoglobin A (HbA1c) levels, we divided patients into 2 groups of HbA1c<7.0 (n=489) and HbA1c≥7.0 (n=491). Propensity score-matched analysis was performed in 322 pairs. The primary outcome was major adverse cardiac and cerebrovascular events (MACCE), defined as a composite of cardiac death, myocardial infarction, repeat revascularization, or stroke. Median follow-up duration was 5.4 years. The 7-year incidence of MACCE was lower in the HbA1c<7.0 group than in the HbA1c≥7.0 group (26.9% versus 40.3%; adjusted hazard ratio, 0.75; 95% confidence interval, 0.57-0.98; P=0.03). After propensity score matching, the 7-year incidence of MACCE was still lower in the HbA1c<7.0 group than in the HbA1c≥7.0 group (27.5% versus 37.4%; hazard ratio, 0.71; 95% confidence interval, 0.52-0.97; P=0.03), mainly because of a reduction in repeat revascularization (19.9% versus 29.5%; hazard ratio, 0.66; 95% confidence interval, 0.47-0.93; P=0.02). In subgroup analyses, the benefit of glycemic control for MACCE was more prominent in patients with residual SYNTAX score (Synergy Between PCI With Taxus and Cardiac Surgery) >4 than in those with the residual SYNTAX score ≤4 (P interaction =0.004). Conclusions-HbA1c<7.0 measured 2 years after percutaneous cor...

Defect engineering has brought about a unique level of control for Si-based semiconductors, leading to the optimization of various opto-electronic properties and devices. With regard to perovskite transition metal oxides, O vacancies have been a key ingredient in defect engineering, as they play a central role in determining the crystal field and consequent electronic structure, leading to important electronic and magnetic phase transitions. Therefore, experimental approaches toward understanding the role of defects in complex oxides have been largely limited to controlling O vacancies. In this study, we report on the selective formation of different types of elemental vacancies and their individual roles in determining the atomic and electronic structures of perovskite SrTiO3 (STO) homoepitaxial thin films fabricated by pulsed laser epitaxy. Structural and electronic transitions have been achieved via selective control of the Sr and O vacancy concentrations, respectively, indicating a decoupling between the two phase transitions. In particular, O vacancies were responsible for metal-insulator transitions, but did not influence the Sr vacancy induced cubic-to-tetragonal structural transition in epitaxial STO thin film. The independent control of multiple phase transitions in complex oxides by exploiting selective vacancy engineering opens up an unprecedented opportunity toward understanding and customizing complex oxide thin films.

BackgroundRecently, a hemoglobin A1c (HbA1c) level of 6.5% has been determined to be a criterion for diabetes mellitus (DM), and it is a widely used marker for the diagnosis of DM. However, HbA1c may be influenced by a number of factors. Anemia is one of the most prevalent diseases with an influence on HbA1c; however, its effect on HbA1c varies based on the variable pathophysiology of anemia. The aim of this study was to determine the effect of anemia on HbA1c levels.MethodsAnemic subjects (n=112) and age- and sex-matched controls (n=217) who were drug naive and suspected of having DM were enrolled. The subjects underwent an oral glucose tolerance test and HbA1c simultaneously. We compared mean HbA1c and its sensitivity and specificity for diagnosing DM between each subgroup.ResultsClinical characteristics were found to be similar between each subgroup. Also, when glucose levels were within the normal range, the difference in mean HbA1c was not significant (P=0.580). However, when plasma glucose levels were above the diagnostic cutoff for prediabetes and DM, the mean HbA1c of the anemic subgroup was modestly higher than in the nonanemic group. The specificity of HbA1c for diagnosis of DM was significantly lower in the anemic subgroup (P<0.05).ConclusionThese results suggest that the diagnostic significance of HbA1c might be limited in anemic patients.

Growth of perovskite oxide thin films on Si in crystalline form has long been a critical obstacle for the integration of multifunctional oxides into Si-based technologies. In this study, we propose pulsed laser deposition of a crystalline SrTiO thin film on a Si using graphene substrate. The SrTiO thin film on graphene has a highly (00l)-oriented crystalline structure which results from the partial epitaxy. Moreover, graphene promotes a sharp interface by highly suppressing the chemical intermixing. The important role of graphene as a 2D substrate and diffusion barrier allows the expansion of device applications based on functional complex oxides.

ObjectivesElevated D-dimer levels on admission predict prognosis in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI), but the association of D-dimer levels with structural markers of myocardial injury in these patients is unknown.MethodsWe performed cardiac magnetic resonance (CMR) imaging in 208 patients treated with primary PCI for STEMI. CMR was performed a median of 3 days after the index procedure. Of the 208 patients studied, 75 patients had D-dimer levels above the normal range on admission (>0.5 μg/mL; high D-dimer group) while 133 had normal levels (≤0.5 μg/mL; low D-dimer group). The primary outcome was myocardial infarct size assessed by CMR. Secondary outcomes included area at risk (AAR), microvascular obstruction (MVO) area, and myocardial salvage index (MSI).ResultsIn CMR analysis, myocardial infarct size was larger in the high D-dimer group than in the low D-dimer group (22.3% [16.2–30.5] versus 18.8% [10.7–26.7]; p = 0.02). Compared to the low D-dimer group, the high D-dimer group also had a larger AAR (38.1% [31.7–46.9] versus 35.8% [24.2–45.3]; p = 0.04) and a smaller MSI (37.7 [28.2–46.9] versus 47.1 [33.2–57.0]; p = 0.01). In multivariate analysis, high D-dimer levels were significantly associated with larger myocardial infarct (OR 2.59; 95% CI 1.37–4.87; p<0.01) and lower MSI (OR 2.62; 95% CI 1.44–4.78; p<0.01).ConclusionsIn STEMI patients undergoing primary PCI, high D-dimer levels on admission were associated with a larger myocardial infarct size, a greater extent of AAR, and lower MSI, as assessed by CMR data. Elevated initial D-dimer level may be a marker of advanced myocardial injury in patients treated with primary PCI for STEMI.