The Korean Society of Heart Failure (KSHF) guidelines aim to provide physicians with evidencebased recommendations for the management of patients with heart failure (HF). After the first introduction of the KSHF guidelines in 2016, newer therapies for HF with reduced ejection fraction, HF with mildly reduced ejection fraction, and HF with preserved ejection fraction have since emerged. The current version has been updated based on international guidelines and research data on Korean patients with HF. Herein, we present Part II of these guidelines, which comprises treatment strategies to improve the outcomes of patients with HF.

The Korean Society of Heart Failure guidelines aim to provide physicians with evidence-based recommendations for diagnosing and managing patients with heart failure (HF). In Korea, the prevalence of HF has been rapidly increasing in the last 10 years. HF has recently been classified into HF with reduced ejection fraction (EF), HF with mildly reduced EF, and HF with preserved EF (HFpEF). Moreover, the availability of newer therapeutic agents has led to an increased emphasis on the appropriate diagnosis of HFpEF. Accordingly, this part of the guidelines will mainly cover the definition, epidemiology, and diagnosis of HF.

Most patients with heart failure (HF) have multiple comorbidities, which impact their quality of life, aggravate HF, and increase mortality. Cardiovascular comorbidities include systemic and pulmonary hypertension, ischemic and valvular heart diseases, and atrial fibrillation. Non-cardiovascular comorbidities include diabetes mellitus (DM), chronic kidney and pulmonary diseases, iron deficiency and anemia, and sleep apnea. In patients with HF with hypertension and left ventricular hypertrophy, renin-angiotensin system inhibitors combined with calcium channel blockers and/or diuretics is an effective treatment regimen. Measurement of pulmonary vascular resistance via right heart catheterization is recommended for patients with HF considered suitable for implantation of mechanical circulatory support devices or as heart transplantation candidates. Coronary angiography remains the gold standard for the diagnosis and reperfusion in patients with HF and angina pectoris refractory to antianginal medications. In patients with HF and atrial fibrillation, longterm anticoagulants are recommended according to the CHA 2 DS 2 -VASc scores. Valvular heart diseases should be treated medically and/or surgically. In patients with HF and DM, metformin is relatively safer; thiazolidinediones cause fluid retention and should be avoided in patients with HF and dyspnea. In renal insufficiency, both volume status and cardiac performance are important for therapy guidance. In patients with HF and pulmonary disease, beta-blockers are underused, which may be related to increased mortality. In patients with HF and anemia, iron supplementation can help improve symptoms. In obstructive sleep apnea, continuous positive airway pressure therapy helps avoid severe nocturnal hypoxia. Appropriate management of comorbidities is important for improving clinical outcomes in patients with HF.

The Korean Society of Heart Failure (KSHF) Guidelines provide evidence-based recommendations based on Korean and international data to guide adequate diagnosis and management of heart failure (HF). Since introduction of 2017 edition of the guidelines, management of advanced HF has considerably improved, especially with advances in mechanical circulatory support and devices. The current guidelines addressed these improvements. In addition, we have included recently updated evidence-based recommendations regarding acute HF in these guidelines. In summary, Part IV of the KSHF Guidelines covers the appropriate diagnosis and optimized management of advanced and acute HF.

Background: This study aimed to investigate the recent prevalence, management, and comorbidities of diabetes among Korean adults aged ≥30 years by analyzing nationally representative data. Methods: This study used data from the Korea National Health and Nutrition Examination Survey from 2016 to 2018, and the percentage and total number of people ≥30 years of age with diabetes and impaired fasting glucose (IFG) were estimated. Results: In 2018, 13.8% of Korean adults aged ≥30 years had diabetes, and adults aged ≥65 years showed a prevalence rate of 28%. The prevalence of IFG was 26.9% in adults aged ≥30 years. From 2016 to 2018, 35% of the subjects with diabetes were not aware of their condition. Regarding comorbidities, 53.2% and 61.3% were obese and hypertensive, respectively, and 72% had hypercholesterolemia as defined by low-density lipoprotein cholesterol (LDL-C) ≥100 mg/dL in people with diabetes. Of the subjects with diabetes, 43.7% had both hypertension and hypercholesterolemia. With regard to glycemic control, only 28.3% reached the target level of <6.5%. Moreover, only 11.5% of subjects with diabetes met all three targets of glycosylated hemoglobin, blood pressure, and LDL-C. The percentage of energy intake from carbohydrates was higher in diabetes patients than in those without diabetes, while that from protein and fat was lower in subjects with diabetes. Conclusion The high prevalence and low control rate of diabetes and its comorbidities in Korean adults were confirmed. More stringent efforts are needed to improve the comprehensive management of diabetes to reduce diabetes-related morbidity and mortality.

As various linezolid resistance mechanisms have been identified in methicillin-resistant Staphylococcus aureus (MRSA), we investigated the molecular characteristics of MRSA with elevated linezolid minimum inhibitory concentrations (MICs), using the VITEK 2 system (bioMérieux, Marcy-l'Étoile, France). Twenty-seven MRSA isolates from 14 patients exhibiting linezolid MICs ≥8 µg/mL were examined by broth microdilution (BMD) test as well as by sequencing for mutations in the 23S rRNA gene or ribosomal proteins (L3, L4, and L22) and the presence of the optrA, cfr, and cfr(B) genes. Of the 27 isolates, four (14.8%) from one patient were confirmed as linezolid resistant by BMD and harbored a 23S rRNA T2500A mutation. The remaining 23 were confirmed as linezolid susceptible, indicating that the linezolid-resistant results were major errors generated by VITEK 2. The most commonly detected mutation (19/27, 70.4%), L3 Gly152Asp, was detected in only linezolid-susceptible isolates. No isolates contained optrA, cfr, or cfr(B) or any L4 or L22 protein alterations. Our results show that the 23S rRNA T2500A mutation was mainly associated with linezolid resistance, while the L3 Gly152Asp mutation was not related to linezolid resistance. A confirmatory test is recommended for VITEK 2 linezolid-resistant results owing to the high probability of false resistant results.

The GENEDIA MTB/NTM Detection Kit (GENEDIA MTB/NTM; Green Cross Medical Science Corp., Chungbuk, Korea) is a multiplex real-time PCR assay used for differential identification of Mycobacterium tuberculosis complex (MTBC) and nontuberculous mycobacteria (NTM). While the importance of differential identification of MTB/NTM is recognized, there is limited data on the performance of GENEDIA MTB/NTM assay to date. A total of 687 consecutive sputum specimens were cultured and analyzed with the GENEDIA MTB/NTM and GENEDIA MTB assays. Nineteen specimens (2.8%) were MTBC-positive, and 69 (10.0%) were NTM-positive based on mycobacterial culture. All specimens showed concordant results for MTBC using both assays, with a kappa value of 1.00, overall sensitivity of 63.2% (12/19), and specificity of 100% (668/668). The overall NTM sensitivity and specificity were 23.2% (16/69) and 99.7% (616/618) for GENEDIA MTB/NTM. The association between NTM-positivity using GENEDIA MTB/NTM and the diagnosis of NTM pulmonary disease was not statistically significant. In conclusion, the two real-time PCR assays showed similar diagnostic performance for MTBC detection. However, the sensitivity for NTM detection was lower than that for MTBC detection.

At the request of the authors, the NRF-support number in ‘Acknowledgements’ is modified.

Unfortunately, the original version of this article had errors in the data displayed in flow diagram.