Abstract Background Several published data suggested that concomitant use of clopidogrel and proton pump inhibitors (PPIs) is associated with reduced antiplatelet efficacy of clopidogrel and increased adverse clinical outcomes. We sought to evaluate the interplay between PPI and clopidogrel on platelet reactivity and long-term clinical outcomes in patients after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation. Methods The PTRG-DES (Platelet function and genoType-Related long-term proGnosis in DES-treated patients) registry is a multi-center, real-world registry of patients who underwent PCI with DES and received dual antiplatelet therapy of aspirin and clopidogrel in South Korea. Patients prescribed with PPI were compared to those without the use of PPI (the control group). The primary outcome was a composite of all-cause death, myocardial infarction, stent thrombosis, and stroke at 5 years. Secondary outcomes included cardiac death, major bleeding, and gastrointestinal bleeding. Adjusted outcomes were compared after 1:2 propensity score (PS) matching analysis. Results Among 13,160 patients, 2235 (17.0%) were prescribed with concomitant PPI at the time of clopidogrel loading. Average age was 64.4 years, 67.2% were men, and 35.1% had diabetes. The PPI group demonstrated a higher on-treatment P2Y12 reaction unit than the control group (p<0.001). The 5-year cumulative incidence of the composite primary outcome was higher in the PPI group (12.1% vs. 9.8%, log-rank p<0.001). After PS matching, the primary outcome was similar between the two groups (12.9% vs. 12.1%, log-rank p=0.24). However, the PPI group with CYP2C19 poor metabolizers showed an increased adjusted risk of the primary outcome (hazard ratio 2.69, p<0.001). Conclusions PPI use in patients with clopidogrel administration after DES implantation was associated with increased platelet reactivity, but similar cardiovascular outcomes in real-world practice. Physicians should be careful when administering PPI with clopidogrel in patients with CYP2C19 poor metabolizers.Distribution of P2Y12 reaction unitCumulative Incidence of outcomes

Abstract Background Elderly patients undergoing percutaneous coronary intervention (PCI) generally have a high risk of adverse clinical outcomes. We investigated the long-term clinical impact of PCI on coronary bifurcation disease in elderly patients in Korea and Italy. Methods From the BIFURCAT (comBined Insights from the Unified RAIN and COBIS bifurcAtion regisTries) data, we evaluated 5,537 patients who underwent PCI for coronary bifurcation disease. The primary outcome was major adverse cardiac events (MACEs), defined as the composite of target vessel myocardial infarction, target lesion revascularisation, and stent thrombosis. Kaplan–Meier estimates and Cox proportional hazard models were used to compare elderly patients (aged ≥75 years) and younger patients (aged <75 years). Results A total of 1,415 patients (26%) were aged ≥75 years. Elderly patients were more frequently female, had higher rates of hypertension and chronic kidney disease (CKD), and presented more frequently with left main (LM) disease. After a median follow-up of 2.1 years, MACEs were comparable between elderly and younger patients. In multivariable analysis, old age was not an independent predictor of MACEs (p=0.977). In elderly patients, CKD and LM disease were independent predictors of MACEs, whereas in younger patients, hypertension, diabetes, CKD, reduced left ventricular ejection fraction, LM disease, and two-stent strategy usage were independent predictors. Conclusions Elderly patients who underwent coronary bifurcation PCI with second-generation drug-eluting stents demonstrated similar clinical outcomes to those of younger patients. Both CKD and LM disease were independent predictors of MACEs, regardless of age after coronary bifurcation PCI. Funding Acknowledgement Type of funding sources: None.

Abstract Background There is little data about clinical role of intravascular ultrasound (IVUS)-guided Percutaneous (PCI) in the setting of ST-segment elevation myocardial infarction (STEMI). Methods From 2005 to 2018, a total of 8,129 patients who underwent PCI with STEMI were investigated from the Korea Acute Myocardial Infarction Registry-National Institute of Health database. Patients with Non-ST segment elevation myocardial infarction, cardiogenic shock, bare metal stent implantation, thrombolytic treatment, and coronary artery bypass graft surgery were excluded. We categorized patients into two groups based on the treatment strategy: IVUS-guided PCI group (n=1,544), and coronary angiography guidance (CAG)-guided PCI group (n=6,585). The primary endpoint was composite of major adverse cardiovascular (MACE), including, cardiac death, myocardial infarction (MI), repeat target vessel revascularization (TVR) and stent thrombosis (ST). Results IVUS-guided PCI was performed in 19% patients (1544/8129). After propensity score matching, there were no statistically difference in the rate of cardiac death (0% in IVUS vs. 0.26% in CAG, p=0.947), MI (2.01% vs. 2.01%, p=0.408), TVR (1.23% vs. 0.91%, p=0.131), ST (0.32% vs. 0.45%, p=0.828) and composite of MACE at 1 year between two groups (2.01% vs. 2.40%, p=0.843). Independent risk factors for MACE were diabetes mellitus and multi-vessel disease, but not IVUS-guided PCI (HR 1.167, 95% CI, 0.896–1.520, p=0.251). Conclusion This study suggests that routine usage of IVUS in the setting of STEMI may not be necessary. Large-scaled random study will be needed for further evaluation. Funding Acknowledgement Type of funding sources: None.

Abstract Background/Introduction Although optimal revascularization strategy in patients with ST-segment elevation myocardial infarction with multivessel coronary artery disease (MVD) was well established, there are few studies which investigated optimal revascularization strategy in non-ST-segment elevation myocardial infarction (NSTEM) with MVD. Purpose We investigated 2-year clinical outcomes according to strategy of revascularization in patients with NSTEMI and MVD. Methods Between November 2011 and October 2015, a total of 2474 patients with NSTEMI and MVD who underwent successful percutaneous coronary intervention were analyzed from the Korea Acute Myocardial Infarction Registry-National Institute of Health (staged 308, one-time 1043 and culprit-only 1123 patients). We did not include patients with left main disease and cardiogenic shock. Primary endpoint was major adverse cardiac events (MACE: the composite of cardiac death, myocardial infarction [MI] or target-vessel revascularization [TVR]) during 2-year follow-up (median 737 days [interquartile range 705–764]). We also analyzed the of all-cause mortality, stroke and non-TVR. Results Baseline characteristics such as age, gender, and prevalence of atherosclerotic risk factors between multivessel revascularization (MVR; staged or one-time revascularization) and CVR were similar. There was also no difference in symptom to balloon time in 2 groups. MACE occurred in 305 patients (12.3%) during 2-year follow-up. MVR could reduce incidence of MACE (10.2% vs. 14.9%; adjusted hazard ratio [HR] 1.50 for CVR, 95% confidence interval [CI] 1.20–1.88, p<0.001), all-cause death (8.4% vs. 12.1%; adjusted HR 1.45 for CVR, 95% CI 1.13–1.87, p=0.003) and non-TVR (1,9% vs. 7.0%; adjusted HR 3.99 for CVR, 95% CI 2.55–6.27, p<0.001). There was no difference in incidence of stroke between MVR and CVR. We also analyzed same analysis between staged and one-time revascularization. Complete revascularization was more achieved in one-time revascularization group compared to staged revascularization group (62.0% vs. 76.1%, p<0.001). In multivariate Cox-regression analysis, staged revascularization was not associated with improved clinical outcomes in terms of MACE (HR 0.74, 95% CI 0.50–1.09, p=0.126), all-cause death (HR 1.07, 95% CI 0.69–1.68, p=0.759), stroke (HR 1.75, 95% CI 0.68–4.52, p=0.245) and non-TVR (HR 2.56, 95% CI 0.75–8.68, p=0.132). Analysis by propensity score matching and inverse probability of treatment weighting did not significantly affect the results. Conclusions MVR reduced 2-year adverse cardiac events in patients with NSTEMI and MVD compared to CVR. However, staged revascularization was not superior to one-time revascularization for reducing MACE among NSTEMI patients with MVD who received MVR.

Abstract Background and objectives The impact of treatment delays to reperfusion on patient mortality after primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI) is controversial. we evaluated the relation between the delay in the time to reperfusion during primary PCI and the 1-year clinical outcome of patients with STEMI treated by primary angioplasty. Methods The study enrolled 6,676 patients (age, 62.5±12.6 years; 26.5% female) with STEMI who underwent primary angioplasty onset between November 2005 and March 2012 from the KAMIR and KorMI Registry. The patients were divided into three groups according to the symptom onset-to-balloon (STB) time: group I, II, III (≤180 minutes, >180 ∼ ≤360 minutes, >360 minutes), and divided into three groups according to the door-to-balloon (DTB) time: group A, B, C (≤90 minutes, >90 ∼ ≤120 minutes, >120 minutes). The 1-year cardiac death and major adverse cardiac event (MACE) rates were compared among the three groups of time variables Results The cardiac death rate was 7.9% and MACE rate was 16.9% at one year follow-up. The 1-year cardiac death rate among STB time groups were significantly higher in group II (95% CI=1.05–2.60:p=0.030) and group III (95% CI=1.14–2.74:p=0.011), while that among DTB time groups were not significantly different based on a multivariate Cox proportional analysis, which was adjusted by age, sex, diabetes mellitus, hypertension, systolic blood pressure, left ventricular ejection fraction, peak level of CK-MB, anterior myocardial infarction. The 1-year MACE rate were not significantly different among STB time groups and DTB time group A, B, but was significantly higher in group C (95% CI=1.08–1.58:p=0.006). Conclusions These results suggest that, in patient with STEMI treated by primary angioplasty, STB time rather than DTB time was related 1-year clinical outcome especially cardiac death after adjustment for baseline characteristics. Therefore, all efforts should be made to shorten the total ischemic time in patients with acute myocardial infarction

The direct discontinuous Galerkin method is used to calculate the viscous flux and the Arbitrary Lagrangian-Eulerian method is adopted so that the fluid analysis domain changes over time. To calculate the higher order numerical flux, we reconstructed the solution using the solution information. First, the TaylorGreen vortex problem is analyzed to confirm the performance of the fluid solver without Arbitrary Lagrangian Eulerian. Second, the flow past a circular cylinder problem is analyzed to confirm the performance of Arbitrary Lagrangian Eulerian solver.

Standard finite volume method based on linear solution reconstruction is considered as second order accurate for solution variables, i.e. pressure and velocity components[1]. The second order accuracy is based on the second order accurate evaluation of the convective flux. However for the computation of viscous flux involving solution derivatives, for example the velocity gradients, is merely first order accurate on general unstructured grids and easily to be degraded from the nominal order of accuracy where mesh regularity is poor. The issue related to the viscous flux computation persists, even for more advanced spatial discretization methods, e.g. discontinuous Galerkin or high-order solution reconstruction, due to possible inconsistency in viscous flux computation[2]. Recently, a very new, efficient, and accurate method is proposed by Nishikawa[4,5], and its applicability towards threedimensional realistic problem is presented by Nishikawa and his co-workers[6]. Also, high-order reconstruction based finite volume method for hyperbolic diffusion system is presented[7]. This method is based on the re-formulation of elliptic nature of the viscous fluxes into a set of augmented variables than makes the entire system to be hyperbolic. In this paper, a hyperbolic incompressible Navier-Stokes (Hyper-INS) system is presented and the solution is obtained by cell-centered finite volume method using unstructured meshes[8]. A very promising result, the uniform order of accuracy not only for the solution variables but also for their gradients are obtainable, will be presented. An even more efficient scheme, so called a hybrid scheme (or scheme II) which utilizing the gradient variables for solution variable reconstruction, is also presented and its superior accuracy is demonstrated.

Introduction: The Cilotax stent®, cilostazol and paclitaxel dual-coating stent (CPD-stent), was created for synergy effect to increase the anti-proliferative effect of paclitaxel and the anti-throm...

In speed skiing, aerodynamic forces play an important role in determining performance of the skier. To predict aerodynamic effects of the posture of the skier on alpine downhill skiing, we constructed equation of motion of the skier and performed the corresponding CFD simulations. Comparing drag and lift of three different skier postures, it has been shown that drag decreases significantly by tucking upper body to lower body and stretching arms forward. Also, aerodynamic lift which worked as downforce in standing posture worked upward in tuck posture, reducing friction force between snow and ski. This indicates that tuck posture have advantages over standing posture in dual mechanism, namely by reducing drag and also increasing lift. By this two-dimensional initial study we could reveal the general tendency of the aerodynamic force over the skier's body. This study not only provides a theoretical foundation for the athletes to understand the aerodynamic effects of skier postures but also shed a light on towards more accurate and rational three-dimensional CFD simulation of skiers in the near future study.

A new and efficient implicit scheme is proposed to obtain a steady-state solution in time integration and the comparison of characteristics with the approximation ways for the implicit method to solve the incompressible Navier-Stokes equations is provided. The conservative, finite-volume cell-vertex upwind scheme and artificial compressibility method using dual time stepping for time accuracy is applied in this paper. The numerical results obtained indicate that the direct application of Jacobian matrix to the Lower and upper sweeps of implicit LU-SG S leads to better performance as well as convergence regardless of CFL number and true time step than explicit scheme and approximation of Jacobian matrix. The flow simulation around box in uniform flow with unstructured meshes is demonstrated to check the validity of the current formulation.

Objectives: Platelet activation plays a pivotal role in the pathogenesis of coronary artery disease. Platelet size, measured as mean platelet volume (MPV) has been reported to be correlated with platelet reactivity. Thus, we aimed to investigate the impact of MPV on 1-year clinical outcomes in patients undergoing percutaneous coronary intervention (PCI).

Objectives: Previous studies have suggested an obesity paradox in patients with coronary artery disease. Because obese patients are also known to have multiple metabolic derangements, therefore, we aimed to investigate the impact of obesity and it's relation with metabolic parameters on clinical outcomes in patient undergoing percutaneous coronary intervention (PCI).