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Background/Aims: Left ventricular hypertrophy (LVH) on clinical outcomes in patients with acute myocardial infarction (AMI) is not clear. This study was performed to investigate the effect of abnormal left ventricular geometry on clinical outcomes in Korean patients with AMI.Methods: A total of 852 consecutive patients with AMI were divided into two groups: normal left ventricular geometry (n = 470; 389 males) and LVH (n = 382; 214 males) groups. Major adverse cardiac events (MACEs) were defined as cardiac death, recurrent myocardial infarction, and rehospitalization.Results: During the clinical follow-up period of 21 ± 7.8 months, MACEs developed in 173 patients (20.0%), and the rate was higher in the LVH than normal left ventricular geometry groups (25.5% vs. 16.0%, respectively, p = 0.001). According to Kaplan-Meier survival curves, the MACE-free survival rate was significantly lower in the LVH group than in the left ventricular geometry group (p = 0.008). The rates of MACEs and all-cause mortality differed among the AMI with concentric remodeling, concentric hypertrophy, and eccentric hypertrophy subgroups (11.2% vs. 15.5% vs. 22.1%, respectively, p = 0.046). Eccentric hypertrophy was a predictive factor of MACE according to Cox proportional hazards analysis (hazard ratio 1.804, confidence interval 1.034-3.148, p = 0.038).Conclusions: LVH is a predictor of poor outcomes in patients with AMI, and eccentric hypertrophy is associated with a worse prognosis compared with concentric remodeling and concentric hypertrophy. Therefore, Korean patients with AMI and LVH, especially eccentric hypertrophy, require more careful observation and intensive treatment.

The main purpose of this study was to evaluate the cooling performances of two different types of cross-flow indirect evaporative coolers (IECs) operated in two different operation modes: general and regenerative. The cooling performances of the IECs were tested in each operation mode in an environmental chamber. In the general mode, the secondary air stream passing through the wet channels was the return air from the conditioned zone; whereas, in the regenerative mode, a portion of the primary air leaving the dry channels was redirected to the secondary channels. The IEC performances were measured under constant primary air inlet temperature and humidity ratio with variations of the primary airflow. As indexes of the IEC performance, the wet-bulb effectiveness and cooling capacity of both IECs in each operation mode were estimated based on the measurement data. The experimental results revealed that, in the general operation mode, both IECs exhibited higher sensible cooling performances in terms of wet-bulb effectiveness than in the regenerative mode in a 100% outdoor air system application.

Desiccant-enhanced evaporative (DEVap) cooling system have been recently introduced as an alternative to conventional air conditioning systems. This system consists of a liquid desiccant dehumidifier and a dew point evaporative cooler. In this research, workable operation strategies for the DEVap system were suggested and applied to an energy simulation for estimating the energy saving potential of the system over the conventional variable air volume (VAV) system. Four different modes of operation determined according to outdoor air conditions were suggested for annual operation of the DEVap system. Energy simulations for both DEVap and VAV systems were performed for a model office building. The results showed that 2–3% of annual primary energy could be saved by using the DEVap cooling system compared with the conventional VAV system.

The purpose of this study is to comparatively evaluate the energy performances of a dedicated outdoor air system (DOAS) and desiccant-enhanced evaporative air conditioner (DEVap) in building applications. The DOAS effectively accommodates latent cooling loads and some of the sensible cooling loads of the space by introducing cooled and dehumidified ventilation air into a building while integrating a parallel system aimed at reducing the remaining sensible load. The DEVap enhances the energy performance of a variable air volume system by reducing cooling coil loads through preconditioning of the supply air before it reaches a coil. The preconditioning is accomplished by using a liquid desiccant system and dew-point indirect evaporative cooler. In this paper, the operating and annual primary energy consumptions of both the DOAS and DEVap systems are compared based on detailed energy simulations. The results indicated the energy saving potential of DOAS to be greater than that of the DEVap. Specifically, a DOAS with ceiling radiant cooling panels experienced 20% less primary energy consumption compared to a DEVap.

The objective of this research is to retrofit a liquid desiccant (LD) and indirect/direct evaporative cooling-assisted 100% outdoor air system (LD-IDECOAS) to enhance its operating energy saving potential. Two retrofit cases of existing LD-IDECOAS have been considered. The first case involves replacing the indirect and direct evaporative coolers with an M-cycle or a dew-point indirect evaporative cooler (i.e., Case 1), and the other one involves adding an enthalpy exchanger before the LD unit of the system in case 1 (i.e., Case 2). By conducting detailed energy simulations for each retrofit case, the improvements in operating energy saving and the coefficient of performance (COP) over the existing LD-IDECOAS were quantitatively evaluated. The results showed that case 1 might provide enhancement in cooling capacity and thermal COP; however, the heating energy consumption for regenerating the desiccant solution increased with the higher process airflow rate when compared to the existing LD-IDECOAS. It was also found that the cooling capacity, thermal COP, and primary COP could be improved by adding a membrane enthalpy exchanger, as done in case 2, without any significant increase in the heating energy consumption for regenerating the desiccant solution.

Objectives The South Korean government required the submission of economic evidence when it implemented the Positive-List System in December 2006. This study investigates the key factors that influenced actual public insurance reimbursement decisions, including the role of economic evidence, after 10 years of decision practice under compulsory health technology assessment (HTA) for new drugs. Method Logistic regression analysis was used to estimate the impact of the variables involved, including cost-effectiveness ratio as a key variable, on reimbursement decisions. The latter were defined as “yes” or “no” at a submitted price and indication. Only cases (n = 91) that present a cost-effectiveness ratio, and that have been reviewed based on this ratio from January 2007 to December 2016, were included in the analysis. Results Cases with higher cost-effectiveness ratios were less likely to be accepted. In addition, drugs that were used to treat severe diseases and drugs with no substitute were more likely to be recommended. The probability of acceptance declined along with the level of uncertainty in the submitted evidence. The acceptance rate for severe-disease drugs has increased since 2013, when the government introduced several policies that lowered the existing barriers to positive reimbursement. However, such an increase was not statistically significant. Conclusions Cost-effectiveness is one of the most influential factors in drug-reimbursement decisions. However, inclusion of other explanatory variables, in addition to the cost-effectiveness ratio, predicted the results of decisions more accurately.

Objective: We analyzed information surveyed from a community-based sample of Korean women older than 40 years of age to understand the relationships between health status and screening behavior. Methods: In a cross-sectional population-based study, a two-stage, geographically stratified household-based sampling design was used for assembly of a probability sample of women aged 40‐69 years living in Gunpo in Korea, resulting in a total sample size of 503 women. The primary outcome variable for this analysis was the respondent’s intention to obtain a mammogram. Predictor variables included health status and other factors known to influence the use of cancer screening, such as age, education, income, marital status and the presence of co-morbid illnesses. Health status was assessed by using the EuroQol (EQ-5D). Results: The median EQ visual analogue scale score was 75.0, ranging from 20 to 100. In bivariate analyses, the percentage of women reporting to have intention toward mammography use decreased with worsening health status. Women who had problems with mobility or anxiety/depression showed lower intention to undergo future screening mammography. Multivariate logistic regression confirmed that health status was significantly associated with intention toward mammography use. Anxiety or depression was an independent predictor of future screening mammography use. Conclusions: Health status is significantly associated with intention regarding screening mammography use. Physicians or other health professionals should be aware that health status is an important component for health promotion, and should pay more attention to clients’ possible vulnerability in screening mammography use due to their poor health status.