Impact of Everolimus Initiation and Corticosteroid Weaning During Acute Phase After Heart Transplantation on Clinical Outcome: Data from the Korean Organ Transplant Registry (KOTRY).

The effect of changes in immunosuppressive therapy during the acute phase post-heart transplantation (HTx) on clinical outcomes remains unclear. This study aimed to investigate the effects of changes in immunosuppressive therapy by corticosteroid (CS) weaning and everolimus (EVR) initiation during the first year post-HTx on clinical outcomes. We analyzed 622 recipients registered in the Korean Organ Transplant Registry (KOTRY) between January 2014 and December 2021. The median age at HTx was 56 years (interquartile range [IQR], 45-62), and the median follow-up time was 3.9 years (IQR 2.0-5.1). The early EVR initiation within the first year post-HTx and maintenance during the follow-up is associated with reduced the risk of primary composite outcome (all-cause mortality or re-transplantation) (HR, 0.24; 95% CI 0.09-0.68; p < 0.001) and cardiac allograft vasculopathy (CAV) (HR, 0.39; 95% CI 0.19-0.79; p = 0.009) compared with EVR-free or EVR intermittent treatment regimen, regardless of CS weaning. However, the early EVR initiation tends to increase the risk of acute allograft rejection compared with EVR-free or EVR intermittent treatment.

Diagnostic Pitfall and Clinical Characteristics of Variant Versus Wild-Type Transthyretin Amyloid Cardiomyopathy in Asian Population: The Korean Nationwide Cohort Study.

BACKGROUND: Transthyretin amyloidosis cardiomyopathy (ATTR-CM) is an under-recognized cause of heart failure (HF) with clinical phenotypes that vary across regions and genotypes. We sought to characterize the clinical characteristics of ATTR-CM in Asia. METHODS: Data from a nationwide cohort of patients with ATTR-CM from six major tertiary centres in South Korea were analysed between 2010 and 2021. All patients underwent clinical evaluation, biochemical laboratory tests, echocardiography, and transthyretin (TTR) genotyping at the time of diagnosis. The study population comprised 105 Asian ATTR-CM patients (mean age: 69 years; male: 65.7%, wild-type ATTR-CM: 41.9%). RESULTS: Among our cohort, 18% of the patients had a mean left ventricular (LV) wall thickness < 12 mm. The diagnosis of ATTR-CM increased notably during the study period (8 [7.6%] during 2010-2013 vs. 22 [21.0%] during 2014-2017 vs. 75 [71.4%] during 2018-2021). Although the duration between symptom onset and diagnosis did not differ, the proportion of patients with HF presenting mild symptoms increased during the study period (25% NYHA class I/II between 2010-2013 to 77% between 2018-2021). In contrast to other international registry data, male predominance was less prominent in wild-type ATTR-CM (68.2%). The distribution of TTR variants was also different from Western countries and from Japan. Asp38Ala was the most common mutation. CONCLUSION: A nationwide cohort of ATTR-CM exhibited less male predominance, a proportion of patients without increased LV wall thickness, and distinct characteristics of genetic mutations, compared to cohorts in other parts of the world. Our results highlight the ethnic variation in ATTR-CM and may contribute to improving the screening process for ATTR-CM in the Asian population.

Real-World Eligibility and Cost-Effectiveness Analysis of Empagliflozin for Heart Failure in Korea.

BACKGROUND: The US Food and Drug Administration (FDA) and European Medicines Agency (EMA) approved empagliflozin for reducing cardiovascular mortality and heart failure (HF) hospitalization in patients with both HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF). However, limited data are available on the generalizability of empagliflozin to clinical practice. Therefore, we evaluated real-world eligibility and potential cost-effectiveness based on a nationwide prospective HF registry. METHODS: A total of 3,108 HFrEF and 2,070 HFpEF patients from the Korean Acute Heart Failure (KorAHF) registry were analyzed. Eligibility was estimated by inclusion and exclusion criteria of EMPagliflozin outcomE tRial in Patients With chrOnic heaRt Failure With Reduced Ejection Fraction (EMPEROR-Reduced) and EMPagliflozin outcomE tRial in Patients With chrOnic heaRt Failure With Preserved Ejection Fraction (EMPEROR-Preserved) trials and by FDA & EMA label criteria. The cost-utility analysis was done using a Markov model to project the lifetime medical cost and quality-adjusted life year (QALY). RESULTS: Among the KorAHF patients, 91.4% met FDA & EMA label criteria, while 44.7% met the clinical trial criteria. The incremental cost-effectiveness ratio of empagliflozin was calculated at US$6,764 per QALY in the overall population, which is far below a threshold of US$18,182 per QALY. The cost-effectiveness benefit was more evident in patients with HFrEF (US$5,012 per QALY) than HFpEF (US$8,971 per QALY). CONCLUSION: There is a large discrepancy in real-world eligibility for empagliflozin between FDA & EMA labels and clinical trial criteria. Empagliflozin is cost-effective in HF patients regardless of ejection fraction in South Korea health care setting. The efficacy and safety of empagliflozin in real-world HF patients should be further investigated for a broader range of clinical applications. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01389843.

Frequency-Selective, Multi-Channel, Self-Powered Artificial Basilar Membrane Sensor with a Spiral Shape and 24 Critical Bands Inspired by the Human Cochlea.

A spiral-artificial basilar membrane (S-ABM) sensor is reported that mimics the basilar membrane (BM) of the human cochlea and can detect sound by separating it into 24 sensing channels based on the frequency band. For this, an analytical function is proposed to design the width of the BM so that the frequency bands are linearly located along the length of the BM. To fabricate the S-ABM sensor, a spiral-shaped polyimide film is used as a vibrating membrane, with maximum displacement at locations corresponding to specific frequency bands of sound, and attach piezoelectric sensor modules made of poly(vinylidene fluoride-trifluoroethylene) film on top of the polyimide film to measure the vibration amplitude at each channel location. As the result, the S-ABM sensor implements a characteristic frequency band of 96-12,821 Hz and 24-independent critical bands. Using real-time signals from discriminate channels, it is demonstrated that the sensor can rapidly identify the operational noises from equipment processes as well as vehicle sounds from environmental noises on the road. The sensor can be used in a variety of applications, including speech recognition, dangerous situation recognition, hearing aids, and cochlear implants, and more.

Metformin treatment is associated with improved survival in diabetic patients hospitalized with acute heart failure: A prospective observational study using the Korean acute heart failure registry data.

AIMS: Although the hypothesis that metformin is beneficial for patients with diabetes and heart failure (HF) has been steadily raised, there is limited data on metformin use in patients with acute HF. We analyzed the association of metformin on all-cause mortality in hospitalized patients with type 2 diabetes and acute HF. METHODS: The Korean Acute Heart Failure registry prospectively enrolled patients hospitalized for acute HF from 2011 to 2014. Among this cohort, we analyzed patients with diabetes with baseline estimated glomerular filtration rate (eGFR) of 30 ml/min/1.73 m2 or more. We analyzed the all-cause mortality and re-hospitalization for HF within 1 year after discharge. Inverse probability treatment weighting method was used to adjust baseline differences on metformin treatment. RESULTS: The study analyzed data from 1,309 patients with HF and diabetes (mean age 69 years, 56 % male). Among them, 613 (47 %) patients were on metformin at admission. During the median follow-up period of 11 months, 132 (19 %) and 74 (12 %) patients not receiving and receiving metformin treatment died, respectively. The mortality rate was lower in metformin users than in non-users (hazard ratio 0.616 [0.464-0.819] P<0.001). After adjustment, metformin was significantly associated with a lower risk for the mortality (hazard ratio 0.677 [0.495-0.928] P=0.015). In subgroup analyses, this association remains significant irrespective of baseline kidney function (eGFR <60 or ≥60 ml/min/1.73 m2, P-for-interaction=0.176) or left ventricular ejection fraction (<40 %, 40-49 %, or ≥50 %, P-for-interaction=0.224). CONCLUSIONS: Metformin treatment at the time of admission was associated with a lower risk for 1-year mortality in patients with diabetes, hospitalized for acute HF.

Eligibility and Cost-Utility Analysis of Dapagliflozin in Patients with Heart Failure Across the Whole Spectrum of Ejection Fraction in South Korea.

BACKGROUND: The DAPA-HF and DELIVER trials demonstrated the clinical benefits of dapagliflozin in heart failure (HF) patients across the entire ejection fraction (EF) spectrum. However, further investigation is needed for the real-world application of dapagliflozin in HF patients. This study examines the proportion of real-world HF patients eligible for dapagliflozin and evaluates the cost-effectiveness of adding dapagliflozin to current HF therapy. METHODS: Data from the nationwide prospective registry, the Korean Acute Heart Failure (KorAHF) registry, were used to determine dapagliflozin eligibility based on the enrollment criteria of the DAPA-HF/DELIVER trials. A cost-utility analysis was conducted using a Markov model to assess the cost-effectiveness of dapagliflozin by comparing it to the standard of care. RESULTS: Out of 5178 KorAHF patients, 48.7% met the enrollment criteria of the DAPA-HF/DELIVER trials, while 89.5% met the label criteria (US Food and Drug Administration, European Medicines Agency, and Korean Ministry of Food and Drug Safety). Eligibility was highest among HF patients with preserved EF (55.3% vs. HF with mildly reduced EF and HF with reduced EF 46.4%). Dapagliflozin proved to be cost-effective, with an incremental cost-effectiveness ratio (ICER) of 4557 US dollar (US$) per quality-adjusted life year, which falls below the US$18,182 willingness-to-pay threshold. The cost-effectiveness benefit was more pronounced in patients with a left ventricular EF (LVEF) ≤ 40% (ICER US$3279 for LVEF ≤ 40% vs. US$8383 for LVEF > 40%). CONCLUSIONS: Discrepancies in dapagliflozin eligibility were observed between real-world data and clinical trial results. The addition of dapagliflozin to HF therapy proved to be highly cost-effective across the entire EF spectrum.

Early stroke after left ventricular assist device implantation: role of right heart failure.

Background: Both stroke and right heart failure (RHF) are common and serious complications after left ventricular assist device (LVAD) implantation. The objective of this study was to evaluate relation between stroke and RHF early after LVAD implantation. Methods: This is a retrospective observational cohort study. From January 2012 to December 2020, patients who underwent LVAD implantation in a single-center were enrolled. Patients with a non-dischargeable LVAD or without follow-up data were excluded. Early stroke was defined as a stroke event within 6 months after implantation. Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) definition was used for the diagnosis of RHF. Results: A total of 70 patients underwent LVAD implantation. Sixty-seven patients (95.7%) were successfully discharged and 16 patients (22.9%) died during follow-up. 14 patients (20.0%) experienced a stroke within 6 months after implantation, and 0.28 stroke events per patient-year occurred during follow-up. Postoperative RHF was more common in the stroke group (64.3% vs. 23.2%, P=0.008) and the median time from implantation to RHF was 1 day. In the Cox multivariable analysis, postoperative RHF [hazard ratio (HR): 5.063; 95% confidence interval (CI): 1.682-15.245; P=0.004], and cerebral perfusion pressure (CPP) on postoperative day (POD) 1 (HR: 0.923; 95% CI: 0.858-0.992; P=0.030) were independent predictors for early stroke. A CPP of 62 mmHg (sensitivity, 71.4%; specificity, 59.3%) was the cutoff value for early stroke according to the receiver operating characteristic (ROC) analysis. Conclusions: RHF after LVAD implantation may be a risk factor for early stroke. Prevention and management of postoperative RHF with adequate CPP could prevent early stroke after LVAD implantation.