Simulation of stress in a blood vessel due to plaque sediments in coronary artery disease.

Atherosclerosis is a cardiovascular disease mainly caused by plaque deposition in blood vessels. Plaque comprises components such as thrombosis, fibrin, collagen, and lipid core. It plays an essential role in inducing rupture in a blood vessel. Generally, Plaque could be described as three kinds of elastic models: cellular Plaque, hypocellular Plaque, and calcified Plaque. The present study aimed to investigate the behavior of atherosclerotic plaque rupture according to different lipid cores using Fluid-Structure Interaction (FSI). The blood vessel was also varied with different thicknesses (0.05, 0.25, and 0.5 mm). In this study, FSI simulation with a cellular plaque model with various thicknesses was investigated to obtain information on plaque rupture. Results revealed that the blood vessel with Plaque having a lipid core represents higher stresses than those without a lipid core. Blood vessels' thin thickness, like a thin cap, results in more considerable than Von Mises stress. The result also suggests that even at low fracture stress, the risk of rupture due to platelet decomposition at the gap was more significant for cellular plaques.

Perioperative Antiplatelet Strategy in Patients Undergoing Noncardiac Surgery Within One Year After Percutaneous Coronary Intervention.

BACKGROUND: The optimal antiplatelet therapy (APT) for patients undergoing non-cardiac surgery within 1 year after percutaneous coronary intervention (PCI) is not yet established. METHODS: Patients who underwent non-cardiac surgery within 1 year after second-generation drug-eluting stent implantation were included from a multicenter prospective registry in Korea. The primary endpoint was 30-day net adverse clinical event (NACE), including all-cause death, major adverse cardiovascular event (MACE), and major bleeding events. Covariate adjustment using propensity score was performed. RESULTS: Among 1130 eligible patients, 708 (62.7%) continued APT during non-cardiac surgery. After propensity score adjustment, APT continuation was associated with a lower incidence of NACE (3.7% vs 5.5%; adjusted odds ratio [OR], 0.48; 95% confidence interval [CI], 0.26-0.89; P = .019) and MACE (1.1% vs 1.9%; adjusted OR, 0.35; 95% CI, 0.12-0.99; P = .046), whereas the incidence of major bleeding events was not different between the 2 APT strategies (1.7% vs 2.6%; adjusted OR, 0.61; 95% CI, 0.25-1.50; P = .273). CONCLUSIONS: The APT continuation strategy was chosen in a substantial proportion of patients and was associated with the benefit of potentially reducing 30-day NACE and MACE with similar incidence of major bleeding events, compared with APT discontinuation. This study suggests a possible benefit of APT continuation in non-cardiac surgery within 1 year of second-generation drug-eluting stent implantation.

Nitrates vs. Other Types of Vasodilators and Clinical Outcomes in Patients with Vasospastic Angina: A Propensity Score-Matched Analysis.

Although vasodilators are widely used in patients with vasospastic angina (VA), few studies have compared the long-term prognostic effects of different types of vasodilators. We investigated the long-term effects of vasodilators on clinical outcomes in VA patients according to the type of vasodilator used. Study data were obtained from a prospective multicenter registry that included patients who had symptoms suggestive of VA. Patients were classified into two groups according to use of nitrates (n = 239) or other vasodilators (n = 809) at discharge. The composite clinical events rate, including acute coronary syndrome (ACS), cardiac death, new-onset arrhythmia (including ventricular tachycardia and ventricular fibrillation), and atrioventricular block, was significantly higher in the nitrates group (5.3% vs. 2.2%, p = 0.026) during one year of follow-up. Specifically, the prevalence of ACS was significantly more frequent in the nitrates group (4.3% vs. 1.5%, p = 0.024). After propensity score matching, the adverse effects of nitrates remained. In addition, the use of nitrates at discharge was independently associated with a 2.69-fold increased risk of ACS in VA patients. In conclusion, using nitrates as a vasodilator at discharge can increase the adverse clinical outcomes in VA patients at one year of follow-up. Clinicians need to be aware of the prognostic value and consider prescribing other vasodilators.

Effect of Significant Coronary Artery Stenosis on Prognosis in Patients with Vasospastic Angina: A Propensity Score-Matched Analysis.

Vasospastic angina (VA) is a functional disease of the coronary artery and occurs in an angiographically normal coronary artery. However, it may also occur with coronary artery stenosis. We investigated the effect of coronary artery stenosis on clinical outcomes in VA patients. Study data were obtained from a prospective multicenter registry that included patients who had symptoms of VA. Patients were classified into two groups according to presence of significant coronary artery stenosis. Among 1920 patients with VA, 189 patients were classified in the "significant stenosis" group. The one-year composite clinical events rate was significantly higher in the significant stenosis group than in the "no significant stenosis" group (5.8% vs. 1.4%, respectively; p < 0.001). Additionally, the prevalence of ACS was significantly greater in the "significant stenosis" group (4.8% vs. 0.9%, respectively; p < 0.001). After propensity score matching, the adverse effects of significant stenosis remained. In addition, significant stenosis was independently associated with a 6.67-fold increased risk of ACS in VA patients. In conclusion, significant coronary artery stenosis can increase the adverse clinical outcomes in VA patients at long-term follow-up. Clinicians should manage traditional risk factors associated with atherosclerosis and control vasospasm as well as reduce the burden of atherosclerosis.

Smoking may be more harmful to vasospastic angina patients who take antiplatelet agents due to the interaction: Results of Korean prospective multi-center cohort.

BACKGROUND: The interaction between smoking and the use of antiplatelet agents on the prognosis of vasospastic angina (VA) is rarely investigated. METHODS: VA-Korea is a nation-wide multi-center registry with prospective design (n = 1812). The primary endpoint was the composite occurrence of acute coronary syndrome (ACS), symptomatic arrhythmia, and cardiac death. Log-rank test and Cox proportional hazard model were for statistical analysis. Also, we conducted interaction analysis in both additive and multiplicative scales between smoking and antiplatelet agents among VA patients. For additive scale interaction, relative excess risk due to interaction (RERI) was calculated and for multiplicative scale interaction, the ratio of hazard ratio (HR) was calculated. All statistical analysis conducted by Stata Ver 16.1. RESULTS: Patients who were smoking and using antiplatelet agents had the highest incidence rate in the primary composite outcome. The incidence rate was 3.49 per 1,000 person-month (95% CI: 2.30-5.30, log-rank test for primary outcome p = 0.017) and HR of smoking and using antiplatelet agents was 1.66 (95%CI: 0.98-2.81). The adjusted RERI of smoking and using antiplatelet agents was 1.10 (p = 0.009), and the adjusted ratio of HR of smoking and using antiplatelet agents was 3.32 (p = 0.019). The current study observed the interaction between smoking and using antiplatelet agents in both additive and multiplicative scales. CONCLUSIONS: Smoking was associated with higher rates of unfavorable clinical outcomes among VA patients taking antiplatelet agents. This suggested that VA patients, especially those using antiplatelet agents should quit smoking.

Consensus Decision-Making for the Management of Antiplatelet Therapy before Non-Cardiac Surgery in Patients Who Underwent Percutaneous Coronary Intervention With Second-Generation Drug-Eluting Stents: A Cohort Study.

Background Although antiplatelet therapy (APT) has been recommended to balance ischemic-bleeding risks, it has been left to an individualized decision-making based on physicians' perspectives before non-cardiac surgery. The study aimed to assess the advantages of a consensus among physicians, surgeons, and anesthesiologists on continuation and regimen of preoperative APT in patients with coronary drug-eluting stents. Methods and Results A total of 3582 adult patients undergoing non-cardiac surgery after percutaneous coronary intervention with second-generation stents was retrospectively included from a multicenter cohort. Physicians determined whether APT should be continued or discontinued for a recommended period before non-cardiac surgery. There were 3103 patients who complied with a consensus decision. Arbitrary APT, not based on a consensus decision, was associated with urgent surgery, high bleeding risk of surgery, female sex, and dual APT at the time of preoperative evaluation. Arbitrary APT independently increased the net clinical adverse event (adjusted odds ratio [ORadj], 1.98; 95% CI, 1.98-3.11), major adverse cardiac event (ORadj, 3.11; 95% CI, 1.31-7.34), and major bleeding (ORadj, 2.34; 95% CI, 1.45-3.76) risks. The association was consistently noted, irrespective of the surgical risks, recommendations, and practice on discontinuation of APT. Conclusions Most patients were treated in agreement with a consensus decision about preoperative APT based on a referral system among physicians, surgeons, and anesthesiologists. The risk of perioperative adverse events increased if complying with a consensus decision was failed. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03908463.

Coronary calcification is associated with elevated serum lipoprotein (a) levels in asymptomatic men over the age of 45 years: A cross-sectional study of the Korean national health checkup data.

ABSTRACT: Lipoprotein a (Lp (a)) and coronary artery calcification (CAC) are markers of coronary artery and cardiovascular diseases. However, the association between Lp (a) and CAC in asymptomatic individuals remains unclear. In this study, we aimed to determine the influence of Lp (a) on CAC in asymptomatic individuals.We included 2019 asymptomatic Korean adults who underwent testing for a coronary artery calcium score (CACS) and Lp (a) at the Gangnam Severance Hospital Health Checkup Center in Korea from January 2017 to August 2019. Participants were divided into 2 groups: CACS = 0 and CACS > 0. Factors affecting the CACS were analyzed by sex. Because age is a major risk factor for atherosclerosis, ≥45 years in men and ≥55 years in women, we further divided participants into 4 subgroups (≥45 and <45 in men, ≥55 and <55 in women). Factors affecting the CACS in the 4 groups were analyzed.There was a positive correlation between the CACS and traditional cardiovascular risk factors. Lp (a) positively correlated with the CACS in men (P < .01) and remained significant after multivariable logistic regression (P < .01). The same result was observed in men aged ≥45 years (P < .01).Lp (a) is an independently associated factor of CAC and a marker of coronary atherosclerosis in asymptomatic men aged ≥45 years. In asymptomatic men aged ≥45 years, Lp (a) should be measured, and intensive Lp (a)-lowering treatment should be considered.

Relationship between Muscle Mass and Non-Alcoholic Fatty Liver Disease.

Although sarcopenia is known to be a risk factor for non-alcoholic fatty liver disease (NAFLD), whether NAFLD is a risk factor for the development of sarcopenia is not clear. We investigated relationships between NAFLD and low skeletal muscle mass index (LSMI) using three different datasets. Participants were classified into LSMI and normal groups. LSMI was defined as a body mass index (BMI)-adjusted appendicular skeletal muscle mass <0.789 in men and <0.512 in women or as the sex-specific lowest quintile of BMI-adjusted total skeletal muscle mass. NAFLD was determined according to NAFLD liver fat score or abdominal ultrasonography. The NAFLD groups showed a higher hazard ratios (HRs) with 95% confidence intervals (CIs) for LSMI than the normal groups (HRs = 1.21, 95% CIs = 1.05-1.40). The LSMI groups also showed a higher HRs with 95% CIs for NAFLD than normal groups (HRs = 1.56, 95% CIs = 1.38-1.78). Participants with NAFLD had consistently less skeletal muscle mass over 12 years of follow-up. In conclusion, LSMI and NAFLD showed a relationship. Maintaining muscle mass should be emphasized in the management of NAFLD.

Impact of PRECISE-DAPT and DAPT Scores on Dual Antiplatelet Therapy Duration After 2nd Generation Drug-Eluting Stent Implantation.

PURPOSE: Determining the optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is an important clinical issue. We evaluated the effects of ischemia (by DAPT score) and bleeding (by PRECISE-DAPT score), as well as the impact of DAPT duration, on clinical outcomes. METHODS: From pooled analysis of four randomized clinical trials, 5131 patients undergoing second-generation DES implantation were randomized to short-duration (n = 2575; ≤ 6 months) or standard-duration (n = 2556; ≥ 12 months) DAPT groups. This population was further divided into four subgroups according to PRECISE-DAPT (high bleeding risk ≥ 25) and DAPT (high ischemic risk ≥ 2) scores. RESULTS: Net clinical outcomes (1.3% vs. 1.3%; p = 0.89) and ischemic events (5.0% vs. 4.5%; p = 0.44) did not differ between the two duration groups, although bleeding events were more frequent in patients with standard-duration DAPT (0.4% vs. 0.9%; p = 0.04). Standard-duration DAPT was associated with fewer ischemic events (6.9% vs. 4.0%; p = 0.02) and no increase in bleeding events only among patients at low bleeding risk and high ischemic risk. The other groups show no differences in net clinical outcomes, ischemic events, or bleeding events according to DAPT duration. CONCLUSION: Compared with short-duration DAPT, standard-duration DAPT was associated with similar net clinical outcomes and ischemic events, but more bleeding events at 12 months after second-generation DES implantation. However, standard-duration DAPT reduced ischemic events without increasing bleeding events among patients at low bleeding and high ischemic risk. When determining DAPT duration, considering both ischemic and bleeding risk can help optimize patient benefits. CLINICAL TRIAL REGISTRATION: EXCELLENT (NCT00698607), RESET (NCT01145079), IVUS-XPL (NCT01308281), OPTIMA-C (NCT03056118).

The Importance of Optimal Gaze Direction on Deep Neck Flexor Activation in Chronic Neck Pain.

Chronic neck pain (CNP) patients have weak deep neck flexors (DNF) and a hyperactive sternocleidomastoid (SCM). The cranio-cervical flexion test (CCFT) promotes activation of the DNF and decreases activity of the SCM, promoting pain recovery, but research suggests SCM activation increases with increasing gaze direction. We aimed to investigate how DNF and SCM activation varies according to gaze direction in the CCFT, and to prescribe the appropriate gaze direction for CNP. Twenty-eight CNP subjects had their maximum strength pressure level determined by CCFT for strength (20-~30 mmHg) and at each of the measured pressures, DNF and SCM thickness in each of four gaze directions (0°, 20°, 40°, and 60°) was measured by ultrasound imaging. The DNF to SCM ratio varied significantly according to gaze direction (p < 0.05), with gaze directions of 20° and 0° being significantly different from 40° (p < 0.05). Although there was no significant difference in DNF activation according to gaze direction, there was in SCM activation (p < 0.05), with SCM 60° significantly different from SCM 20° and SCM 40° (p < 0.05). In order to increase DNF activation efficiency during the CCFT, SCM activation should be controlled, and a gaze direction below 20° is the most efficient. This can inform DNF training of CNP patients in a clinical environment.

Preventive Effect of Pretreatment with Pitavastatin on Contrast-Induced Nephropathy in Patients with Renal Dysfunction Undergoing Coronary Procedure: PRINCIPLE-II Randomized Clinical Trial.

This study aimed to evaluate the efficacy of pitavastatin pretreatment on contrast-induced nephropathy (CIN) in patients with chronic kidney disease (CKD) after a coronary procedure. This was a prospective, randomized, double-blinded, placebo-controlled, multicenter clinical trial. All consecutive 70 patients with CKD (eGFR < 60 mL/min/1.73 m2) were enrolled and randomized into two groups. Group I consisted of patients who were treated with statins (pitavastatin 4 mg/day) for seven days before and three days after the procedure (n = 37, 52.9%), and group II consisted of patients who were treated with a placebo (n = 33, 47.1%). The primary endpoint was the incidence of CIN, and the secondary endpoints were the change in serum creatinine (∆sCr) level and estimated glomerular filtration rate (∆eGFR) after the procedure. The mean age of the patients (males, 74%) was 70.4 ± 9.0 years. After the coronary procedure, the incidence of CIN was lower in group I than in group II, but the difference was not significant (5.4% vs. 9.1%, p = 0.661). The maximal ∆sCr was lower and the maximal ∆eGFR was higher in group I than in group II, but the difference was not significant (-0.11 ± 0.53 mg/dL and -0.04 ± 0.33 mg/dL, p = 0.678; 4.3 ± 11.2 mL/min/1.73 m2 and -2.9 ± 20.4 mL/min/1.73 m2, p = 0.161, respectively). This study showed the possibility of a clinical benefit of pretreatment with a high dose of pitavastatin for the prevention of CIN in patients with CKD after coronary procedure (ClinicalTrials.gov Identifier: NCT01871792).

Platelet thrombus formation by upstream activation and downstream adhesion of platelets in a microfluidic system.

Platelet activation causes platelet aggregation and their adhesion to the vascular wall. In the circulatory environment, platelet activation and adhesion might not occur at the same site. In this study, we developed a microfluidic platform to examine platelet adhesion and aggregation under pathophysiological shear flow. Upstream platelet activation was conducted either using agonists or by shear flow, whereas downstream platelet adhesion was induced using collagen-coated microbeads packed in a tube. Adopting microbeads, activated platelets led to rapid occlusion and blood flow arrest. The degree of platelet adhesion and aggregation was monitored by measuring the blood migration distance, allowing a flow-through in the microchannel until it was blocked. Downstream platelet adhesion was strongly dependent on the upstream activation parameters including shear rate ranges between 754 and 2400 s-1, shearing time greater than 10 s, and incubation time greater than 20 s. Furthermore, through the integration of various leading-edge technical elements, the present system produced comprehensive real-time results of platelet-associated thrombus formation. Thus, this disposable device might help examine platelet dysfunction for preoperative patients and antiplatelet therapy in the clinic.

Patterns of Antiplatelet Therapy During Noncardiac Surgery in Patients With Second-Generation Drug-Eluting Stents.

Background Continuing antiplatelet therapy (APT) has been generally recommended during noncardiac surgery, but it is uncertain if preoperative discontinuation of APT has been avoided or harmful in patients with second-generation drug-eluting coronary stents. Methods and Results Patients undergoing noncardiac surgery after second-generation drug-eluting coronary stent implantation were assessed in a multicenter cohort in Korea. Net adverse clinical events within 30 days postoperatively, defined as all-cause death, major adverse cardiac events, and major bleeding, were evaluated. Of 3582 eligible patients, 49% patients discontinued APT during noncardiac surgery. The incidence of net adverse clinical events was comparable between patients with continuation versus discontinuation (4.1% versus 3.4%; P=0.257) of APT during noncardiac surgery. Perioperative discontinuation of APT did not impact on net adverse clinical events (adjusted hazard ratio [HR], 1.00; 95% CI, 0.69-1.44; P=0.995). In subgroup analysis, patients undergoing intra-abdominal surgery were exposed to less risk of major bleeding by discontinuing APT (adjusted HR, 0.26; 95% CI, 0.08-0.91; P=0.035). Prolonged discontinuation of APT for ≥9 days was associated with higher risk of a major adverse cardiac event compared with continuing APT (adjusted HR, 3.38; 95% CI, 1.36-8.38; P=0.009). Conclusions APT was discontinued preoperatively in almost half of patients with second-generation drug-eluting coronary stents. Our explorative analysis showed that there was no significant impact of discontinuing APT on the risk of perioperative adverse events except that discontinuing APT may be associated with decreased hemorrhagic risk in patients undergoing intra-abdominal surgery. Registration URL: https://www.clini​caltr​ials.gov; Unique identifier: NCT03908463.

Efficacy and Safety of Guideline-Recommended Risk Score-Directed Dual Antiplatelet Therapy After 2nd-Generation Drug-Eluting Stents.

BACKGROUND: Evaluate the safety and efficacy of guideline-recommended risk score-directed dual antiplatelet therapy (GD-DAPT) based on THE PRECISE-DAPT score after 2nd-generation drug-eluting stent (DES) implantation.Methods and Results:We analyzed 5,131 patients pooled from 4 clinical trials. Patients were divided into 3 groups according to current recommendations on the duration of DAPT and their actual DAPT duration: GD-DAPT (n=2,183), shorter DAPT (n=1,540), longer DAPT (n=1,408). The primary endpoint was the rate of net adverse clinical events (NACE) during the first 12 months. The secondary endpoints were ischemic or bleeding events. Overall, GD-DAPT did not affect NACE (1.2% vs. 1.2% for shorter DAPT and 1.7% for longer DAPT) or bleeding events (0.6% vs. 0.5% and 0.9%), and there were fewer ischemic events (2.8% vs. 4.4% and 4.0%, P=0.03) than with shorter DAPT. Especially in acute coronary syndrome (ACS) patients, GD-DAPT had fewer NACE (1.5% vs. 1.4% and 4.2%; P=0.006) and bleeding events (0.8% vs. 0.5% and 2.8%; P=0.001) than longer DAPT as well as fewer ischemic events (2.8% vs. 4.4% and 4.7%; P=0.03) than shorter DAPT. CONCLUSIONS: GD-DAPT did not affect NACE or bleeding events and reduced the number of ischemic events at 12 months compared with shorter DAPT. For ACS, GD-DAPT was associated with favorable outcomes compared with non-GD-DAPT. Therefore, GD-DAPT may optimize efficacy and safety.

Clopidogrel plus Aspirin Use is Associated with Worse Long-Term Outcomes, but Aspirin Use Alone is Safe in Patients with Vasospastic Angina: Results from the VA-Korea Registry, A Prospective Multi-Center Cohort.

Anti-platelet agents are commonly used in vasospastic angina (VA) patients with comorbidity like coronary artery disease. However, long-term clinical outcomes in the use of aspirin, clopidogrel or the two agents together have rarely been investigated in VA patients. In a prospective study, we enrolled 2960 patients who received coronary angiography and ergonovine provocation test at 11 university hospitals in Korea. Among them, 1838 patients were diagnosed either with definite (n = 680) or intermediate (n = 1212) VA, using the criteria of chest pain, ECG changes and ergonovine provocation test results. They were analyzed according to their use of aspirin, clopidogrel or both, or no anti-platelet agent at all. The primary outcome was time to composite events of death from any cause, acute coronary syndrome (ACS) and symptomatic arrhythmia during a 3-year follow-up. A primary composite outcome was significantly more common in the aspirin plus clopidogrel group, at 10.8% (14/130), as compared with the non-antiplatelet group, at 4.4% (44/1011), (hazard ratio [HR] 2.41, 95% confidence interval [CI], 1.32-4.40, p = 0.004). With regard to the person-time event rate, similar results were shown, with the highest rate in the aspirin plus clopidogrel user at 4.72/1000 person months (95% CI, 2.79-7.96, log-rank test for primary outcome p = 0.016). The person-time event of the ACS rate was also highest in that group, at 2.81 (95% CI, 1.46-5.40, log-rank test for ACS p = 0.116). Kaplan-Meier survival analysis demonstrated poor prognosis in primary outcomes and ACS in aspirin plus clopidogrel users (log-rank test, p = 0.005 and p = 0.0392, respectively). Cox-proportional hazard regression analysis, adjusting for age, sex, history of coronary heart disease, hypertension, diabetes, presence or not of definite spasm, use of calcium channel blocker, demonstrated that the use of aspirin plus clopidogrel is an independent risk for the primary outcome (HR 2.01, CI: 1.07-3.81, p = 0.031). The aspirin-alone group had a similar primary and individual event rate compared to the no-antiplatelet agent group (HR 0.96, CI, 0.59-1.55, p = 0.872). Smokers using aspirin plus clopidogrel had poorer outcomes than non-smokers, with HR 6.36 (CI 2.31-17.54, p = 0.045 for interaction). In conclusion, among VA patients, aspirin plus clopidogrel use is associated with a poor clinical outcome at 3 years, especially in ACS. Aspirin alone appears to be safe for use in those patients.

Association between circadian preference and blood lipid levels using a 1:1:1 propensity score matching analysis.

BACKGROUND: Previous studies indicate that circadian preference is associated with various energy metabolism and metabolic disorders. However, little is known about the associations between a circadian rhythm and blood lipid levels, especially in humans. OBJECTIVE: The aim of the study was to investigate whether the circadian rhythm affects serum lipid levels in Korean adults. METHODS: We designed a cross-sectional study to evaluate the associations between circadian preference and blood lipid levels in Korean adults. A total of 1984 participants (range of age 19-81 years) were included in this study. Propensity scores were calculated using logistic regression with age, sex, and body mass index. A total of 435 subjects were evaluated by propensity score matching analysis, equally distributed into morningness, intermediate, and eveningness groups, each with 145 subjects. Circadian preference was evaluated by the Morningness-Eveningness Questionnaire. RESULTS: Participants with the evening preference had significantly higher levels of total cholesterol, triglyceride, low-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol (non-HDL-C) when compared with those with morning or intermediate preference, after adjusting for confounding variables. Regarding other lipid parameters, both total cholesterol/HDL-C and low-density lipoprotein cholesterol/HDL-C in the evening preference are significantly higher than those of other circadian preferences. Evening preference was also significantly associated with a higher atherogenic index of plasma. CONCLUSION: Our study demonstrates that there is a significant association between circadian preference and blood lipid levels. Our findings suggest that individuals with evening preference could have a greater risk of atherosclerotic cardiovascular diseases.

Recent advances in microfluidic platelet function assays: Moving microfluidics into clinical applications.

The analysis of platelet aggregation and thrombosis kinetics has significantly advanced with progress in microfluidic technology. However, the results of platelet aggregation tests do not fully reflect the observed clinical outcomes. To address the present unmet clinical needs, the basic but essential biology of platelets should be reconsidered in relation to the characteristics of microfluidic systems employed for platelet tests. To this end, the present article provides an overview of commercially available point of care devices and focuses on recent microfluidic studies, describing their measurement principles. We critically discuss the characteristics of the microfluidics systems used to evaluate the complex processes underlying platelet aggregation, and that are specifically designed to mimic the pathophysiological environment of blood vessels, including hemodynamic factors as well as blood vessel injury. To this end, we summarize unsolved issues related to the application of platelet function tests based on microfluidics. Overall, we confirm that platelet function tests based on microfluidics provide a versatile platform that encompasses a variety of basic research, as well as clinical diagnostic applications.

Usability evaluation of communication service robot for the elderly.

BACKGROUND: The Republic of Korea has become the most rapidly aging society and is anticipated to enter the post-aged society in 2026. As the population ages, demand for senior-friendly products has gradually increased. Under the demands for these circumstances, usability evaluation aimed to make these products more competitive in terms of quality has been perceived as a critical means. In particular, ergonomically wrong-designed products could prove fatal to elderly people. OBJECTIVE: The purpose of the study is to develop qualitative usability evaluation criteria of communication service robot, one of the senior-friendly products, for elderly people. METHODS: To develop the usability testing criteria of a communication service robot for elderly people. The following was carried out: product selection, selection of target product, development of leading indicators, correction by experts, and preliminary evaluation according to the scenario and development of core indicators. For this, a draft questionnaire was developed for the elderly at around age 60. After small group tests and interviews, the experts modified the initial draft to the usability evaluation criteria of communication service robot for elderly people. RESULTS: Development indicators include four subscales: safety, controllability, efficiency, and satisfaction. All the subscales passed the reliability criteria by four groups of elderly people, divided by gender and the familiarity witth smart move devices. CONCLUSIONS: Development indicators cover a wider area of user experiences of the communication service robot and are a good measurement tool to help both the users and developers of the service robot for elderly people.

A comparison of ultrasonography measurement on the abdominal muscle thickness between adolescent idiopathic scoliosis and healthy subjects.

BACKGROUND: Many studies have shown asymmetric behavior of the surface and deep layers of spine muscles in scoliosis patients, compared to normal individuals. However, there is a lack of research on the transversus abdominal (TA) muscle, which plays an important role in trunk stabilization. OBJECTIVE: To assess symmetry in subjects with adolescent idiopathic scoliosis (AIS) by measuring the thickness of abdominal muscles, and to investigate characteristic features through a comparative analysis of the data with healthy aged-matched group. METHODS: Subjects consisted of 33 AIS and 32 healthy subjects of similar ages between 11-28 years old. We measured TA, internal abdominal oblique (IO), and external abdominal oblique (EO) muscles were measured using ultrasonography imaging. Three repeat measurements of the thickness of each muscle were performed during rest and contraction. RESULTS: For the healthy subjects, the intra-class correlation coefficients (ICCs) for the muscle thickness measures ranged from 0.70 to 0.99, standard error of measurement (SEM) was 0.38 cm, and minimal detectable change (MDC) was 1.07 cm. The ICCs for the muscle thickness measures in the AIS group ranged from 0.90 to 0.98, SEM was 0.45 cm, and MDC was 1.24 cm. The symmetry of the two groups was compared, and showed significant difference only in TA in AIS patient group (P< 0.01). CONCLUSIONS: In conclusion, treatment should be focused on exercises that emphasize symmetry, to induce normal action of the TA and structural changes in the spine because AIS induces asymmetry in TA, which plays an important role in trunk stability.

Safety of six-month dual antiplatelet therapy after second-generation drug-eluting stent implantation: OPTIMA-C Randomised Clinical Trial and OCT Substudy.

AIMS: There are few randomised studies concerning the optimal duration of dual antiplatelet therapy (DAPT) for patients who receive a second-generation drug-eluting stent (DES). This trial aimed to investigate the safety of six-month compared with 12-month DAPT maintenance after second-generation DES implantation. METHODS AND RESULTS: A prospective, randomised, multicentre trial was performed at 10 medical centres. The 1,368 patients included in the study received a biolimus-eluting stent (BES) or a zotarolimus-eluting stent (ZES). The primary outcome measured was the composite of major adverse cardiac events (MACE), including cardiac death, myocardial infarction (MI), or ischaemia-driven target lesion revascularisation at the 12-month follow-up. The secondary outcome was the percentage of uncovered struts at six months in 60 patients (30 ZES, 30 BES) using optical coherence tomography (OCT) assessment. Each patient was randomly assigned to six-month (n=684) or 12-month DAPT (n=684). Major adverse cardiac events at 12 months occurred in eight patients (1.2%) in the six-month DAPT group and in four patients (0.6%) in the 12-month DAPT group (risk difference 0.6%; 95% confidence interval [CI]: -0.4-1.6%; p=0.24). The upper 95% CI limit was lower than the pre-specified limit of 4% non-inferiority (p for non-inferiority <0.05). The percentage of uncovered struts was 3.16±4.30% at six months in 60 stents of 60 patients. CONCLUSIONS: After second-generation DES implantation, six-month DAPT was not inferior to 12-month DAPT in terms of MACE occurrence over the 12-month follow-up period. OCT examination revealed favourable stent strut coverage at six months after stent implantation.