Background and Objectives: Clinical characteristics and outcomes in acute heart failure (AHF) vary by phenotype. We assessed phenotype-specific features, treatment patterns, and outcomes in a nationwide Korean cohort. Methods: The Korean Heart Failure III registry prospectively enrolled 7,351 AHF admissions at 47 hospitals. Among 6,777 patients with available left ventricular ejection fraction (EF), phenotypes were defined as heart failure with reduced EF (HFrEF, ≤40%), mildly reduced EF (HFmrEF,41–49%), or preserved EF (HFpEF, ≥50%). The primary endpoint was a 12-month composite of all-cause death or heart transplantation, evaluated from index admission and, among hospital survivors, from discharge. We used inverse probability weighting (multinomial generalized boosted models with stabilized, trimmed weights) and weighted Cox proportional-hazards models to estimate hazard ratios (HRs). Results: Phenotype distribution was 58.9% HFrEF, 13.6% HFmrEF, and 27.5% HFpEF. Crude 12-month composite rates from index admission were 13.4% (HFrEF), 12.7% (HFmrEF), and 16.8% (HFpEF). After weighting, from index admission, HFmrEF (HR, 0.892; 95% confidence interval [CI], 0.731–1.088) and HFpEF (HR, 1.101; 95% CI, 0.939–1.291) did not differ from HFrEF; from discharge, HFpEF had modestly higher risk (HR, 1.207; 95% CI, 1.008–1.445) whereas HFmrEF did not (HR, 1.039; 95% CI, 0.844–1.279). Hyponatremia and chronic kidney disease were consistent adverse markers, while angiotensin-converting enzyme inhibitor/ angiotensin II receptor blocker use at discharge was protective. Conclusions Across the EF spectrum, phenotypes showed distinct profiles and risk. Postdischarge risk was modestly higher in HFpEF, supporting phenotype-tailored care and systematic discharge optimization in Korean patients with AHF.

Heart failure (HF) prevalence and associated socio-economic costs have risen rapidly in Korea, creating urgent demand for a national, standardized prospective registry to support quality monitoring, outcome comparison, and real-world evidence. Standardized data definitions are essential for valid comparisons across studies and healthcare settings. We created a unified national HF cohort by integrating the two largest Korean registries, KorAHF (2011–2014;n=5,625) and KorHF III (2018–2023; n=7,351), yielding 12,976 hospitalized HF patients. Because heterogeneous variable definitions impeded direct comparisons, we implemented a harmonization pipeline across demographic, clinical, imaging, biomarker, therapeutic, and outcome domains, aligned with international standards and reinforced by systematic data quality checks.A multidisciplinary panel then conducted a structured decision process to produce the Korean HF Standard Dataset, a tiered and interoperable variable set spanning six domains: demographics, presentation at admission, in-hospital events and comorbidities, discharge status, outpatient follow-up, and readmission events. This integrated platform and standardized variables enable precise identification of HF patient phenotypes and prognostic factors, establishing an evidence-based foundation for disease management. This supports an analysis of temporal changes in treatment patterns and outcomes, generates data to inform future clinical practice guidelines, and provides a practical basis for planning large, continuous, prospective HF registries. Furthermore, it also facilitates pragmatic, registry-based randomized clinical trials and unmet-needs assessments that can guide national health policy. Establishing a foundation for future linkage with national health databases, this platform will allow for enhanced accuracy, comparability, and representativeness, powering quality improvement initiatives and population-level monitoring of Korea’s growing HF burden.

Background and Objectives: Heart failure (HF) imposes a significant global burden, yet awareness and implementation of guideline-directed management remain suboptimal. This study evaluated HF awareness, diagnostic patterns, and therapeutic strategies among physicians in Korea. Methods: A nationwide online survey was conducted from July to August 2019, targeting primary care physicians (PCPs; n=8,000) and hospital-based cardiology specialists (n=1,339) across Korea. The questionnaire comprised 23 items covering baseline characteristics, perceptions of HF prognosis, diagnostic approaches, and treatment practices. Results: A total of 543 physicians responded (209 PCPs and 334 cardiology specialists). While the majority correctly defined HF, a substantial proportion underestimated the lifetime risk and poor prognosis. Cardiology specialists were more likely than PCPs to use objective diagnostic tools, including echocardiography (97% vs. 61%, p<0.001) and natriuretic peptide testing (90% vs. 57%, p<0.001). Among PCPs, 29% reported diagnosing HF based on symptoms and physical findings without objective testing, and 27% reported referring patients to general hospitals for diagnostic evaluation. Prescription rates for guideline-directed medical therapies, including renin-angiotensin system blockers and beta-blockers, were consistently higher among cardiology specialists.PCPs more frequently cited advanced age as a barrier to prescribing evidence-based medications. Conclusions Physicians’ awareness and clinical practices regarding HF in Korea remain suboptimal. Given the growing burden, high mortality, and substantial costs of HF, early detection, appropriate diagnostic evaluation, and timely referral are essential. Targeted education and system-level strategies to improve guideline implementation, particularly in primary care settings, are warranted.

In patients with differentiated thyroid cancer (DTC), initial recurrence risk stratification based on clinical, histopathological, and perioperative data remains the key determinant for guiding management strategies during the first 1-2 years post-treatment. However, the adoption of ongoing risk stratification (ORS), which dynamically reassesses risk by integrating longitudinal clinical data and treatment response, enables more precise long-term prognostic assessment and facilitates highly individualized management. Building upon recent guidelines, the 2026 KTA guideline has been further refined by incorporating robust evidence from large-scale national cohorts and comprehensive systematic reviews. These updated recommendations outline contemporary concepts of ORS, risk-adapted TSH suppression targets, optimized surveillance modalities for recurrence detection, and disease-specific long-term follow-up strategies. Reflecting the paradigm shift toward de-escalated treatment, this revision integrates evolved perspectives on TSH suppression intensity, the clinical interpretation of thyroglobulin levels, and tailored follow-up intervals. These evidence-based recommendations aim to minimize unnecessary treatment and excessive surveillance in the large proportion of patients with excellent prognosis after initial therapy, while ensuring that each patient receives appropriately tailored and effective long-term management.

G protein-coupled receptors (GPCRs), commonly known as seven-transmembrane domain receptors, represent one of the largest and most functionally diverse families of membrane receptors. These receptors mediate cellular responses to external signals, thereby influencing various physiological processes. Recent studies have increasingly highlighted the importance of GPCRs in skeletal health, particularly in regulating bone metabolism and the pathogenesis of bone diseases, such as osteoporosis and osteoarthritis. Among GPCRs, a specific subset that responds to fatty acids, including GPR40, GPR120, GPR41, GPR43, GPR84, and GPR119, has received significant attention for its role in skeletal homeostasis. Acting as lipid sensors, these receptors detect changes in fatty acid availability and transduce signals that modulate the differentiation, function, and survival of key bone cell populations, including osteoclasts, osteoblasts, and chondrocytes. This review provides a comprehensive overview of the current understanding of fatty acid-sensing GPCRs in skeletal metabolism, highlighting their potential as novel therapeutic targets for metabolic bone diseases.

Background: There are limited long-term clinical outcome data comparing first-generation (1G) versus second-generation (2G) drug-eluting stents (DES) in patients with single-vessel disease (SVD). We sought to compare the efficacy and safety of 1G- and 2G-DES in SVD patients who underwent successful percutaneous coronary intervention (PCI) over 10 years of clinical follow-up. Methods: A total of 2,312 consecutive patients with SVD who underwent PCI with 1G-DES (paclitaxel- or sirolimus-eluting stents, n = 811) or 2G-DES (zotarolimus [Endeavor, Endeavor Resolute]- or everolimus-eluting stents [Promus Element, Xience], n = 1,082) were enrolled.After propensity score matching, 2 matched groups (538 pairs) were generated. Study endpoints included individual and composite clinical outcomes through 10 years. Results: During the 10-year follow-up, the 2G-DES group had lower incidences of myocardial infarction (MI; hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.22–0.92; P = 0.028) and target lesion revascularization (TLR; HR, 0.54; 95% CI, 0.32–0.91; P = 0.021) than the 1G-DES group. Rates of total death, cardiac death, non-target vessel revascularization, stroke, major adverse cardiac events, and major adverse cardiac and cerebrovascular events were similar between groups. Conclusions In our single-center, all-comer registry, 2G-DES were associated with lower incidence rates of MI and TLR compared to 1G-DES in SVD patients over 10 years of followup, indicating a safer and more durable effect than 1G-DES.

Background: Workers are commonly exposed to diesel engine exhaust (DEE) from diesel-powered engines and vehicles (DEVs), which contain harmful particulates such as black carbon (BC). This study aimed to characterize the peak BC exposures of workers operating or working near DEVs. Methods: BC levels were recorded every minute from workers driving or working near DEVs using a portable aethalometer and were categorized by job type and activity. Peak BC levels were characterized using the occupational exposure limits for DEE (measured as elemental carbon) of 10 μg/m 3 and 50 μg/ m3 as cut-off values. Results: Forklift operators, garbage collectors, and machine operators showed peak BC exposure levels surpassing 20 μg/m 3 , with average levels above 10 μg/m 3 . Despite their short exposure durations (<1 hour), these peaks contributed significantly (>60%) to the daily average BC exposure. The daily contribution rate of peak exposures above 10 μg/m 3 to the average daily BC exposure often exceeded 50%. The ratio of peak levels above 10 μg/m 3 and 50 μg/m 3 to the arithmetic mean was negatively correlated with exposure duration, the proportion of exposure duration, and the daily contribution of peak levels. Conclusion Drivers of diesel-engine vehicles often experienced significant spikes in BC exposure, highlighting the need for real-time monitoring, which is recommended as a best-practice approach to identify and mitigate short-term peak exposures.

Background: The Act on Decisions on Life-Sustaining Treatment (LST) has been implemented in Korea since 2018, yet data on its application in neurocritical care units remain scarce. This study aimed to evaluate the clinical characteristics and outcomes of LST withdrawal or withholding in the neurocritical care unit. Methods: This study was a retrospective analysis conducted at a tertiary university hospital in Busan, South Korea. Among patients admitted to the neurocritical care unit between February 2018 and August 2023, those with documented decisions for LST withdrawal or withholding were enrolled. Demographic and clinical characteristics, underlying and combined conditions, reasons for LST decisions, measures taken, and time from LST withdrawal to death were extracted from medical records. Results: A total of 69 patients were included, with a median age of 67 years, and 38 (55%) were male. Cerebrovascular disease (62%) and traumatic brain injury (22%) were the most common underlying diagnoses. The primary reason for LST decisions was irreversible neurological damage (71%), followed by systemic complications (19%). Mechanical ventilation cessation (91%) and extubation (86%) were most frequently used measures for LST withdrawal. The median time from LST withdrawal to death was 22 minutes. Conclusions Our study demonstrates that LST decisions in the neurocritical care unit predominantly occur among patients with cerebrovascular disease or traumatic brain injury, mostly triggered by neurological deterioration. Most patients died shortly after withdrawal. These findings provide important insight into current LST withdrawal practices in neurocritical care and may assist clinical and ethical decision making in similar settings.

Purpose: To propose improvements for promoting eyeball donation and managing donated corneas, this study analyzed the current system in Korea and reviewed relevant Korean laws, international standards, and foreign practices. Methods: To understand the current situation in Korea, annual reports published by the Korean Network for Organ Sharing and existing Korean laws were examined. For the international context, references were made to the National Organ Transplant Act, 21 CFR Part 1271 (Code of Federal Regulations Title 21 Part 1271), Current Good Tissue Practice guidelines of the Food and Drug Administration, and the Medical Standards of the Eye Bank Association of America in the United States. Opinions on promoting eyeball donation, improving the monitoring system for donated corneas and revising laws related to cornea management were gathered. The perspectives of 31 experts affiliated with the Korea Cornea Society were collected through a survey. Results: Currently, there are no laws or regulations that can be appropriately applied to the cornea which has properties of both organs and tissue. Additionally, there is no law regulating imported corneas. Therefore, there is a need to legislate or revise the current law; all experts who conducted the survey agreed on this. Furthermore, the current system faces limitations in the efficient procurement, stable supply, and management of donor corneas, as well as in donation promotion. To address these issues, the establishment of independent legislation for managing donated corneas and a National Central Eye Bank was proposed. This central body would oversee continuous personnel training, education, and monitoring, along with ensuring stable procurement, processing, and supply of corneas within a structured management system. Sixty-eight percent of the surveyed experts agreed with this proposal. Conclusions To establish a safe and efficient Korean corneal supply and demand system, it is imperative to enact cornea-specific laws, including the establishment of a National Central Eye Bank.

Purpose: To compare the efficacy of the gas-tank method with that of the disposable-gas method in delivering intraocular perfluoropropane (C3F8) tamponade during vitrectomy. Methods: This retrospective study included patients who underwent vitrectomy with C3F8 gas tamponade for retinal detachment between January 2014 and November 2023. In total, 152 patients were categorized into the gas-tank (47 patients) and disposable- gas (105 patients) groups. It was assumed that the gas reached its maximum intraocular volume at 72 h post-injection. The half-life and residual duration of the gas were calculated based on the assumption that the logit-transformed gas volume followed a linear decay. These parameters, along with intraocular pressure (IOP) measurements at postoperative day 1, day 3, week 1, month 1, and month 2, were compared between the two groups. Results: The mean half-life of C3F8 gas was significantly longer in the disposable-gas group (29.10 days) compared to the gas-tank group (25.68 days) (p = 0.000). The residual duration of the gas was also significantly longer in the disposable-gas group (55.34 days, p = 0.000). Furthermore, the variance in half-life was notably smaller in the disposable-gas group (17.80) than in the gas-tank group (34.74), indicating greater consistency. No statistically significant differences in IOP were observed between the two groups at any postoperative time point. Conclusions Vitrectomy using disposable C3F8 gas for retinal detachment is an effective surgical technique that provides consistent and accurate intraocular gas concentrations.