OBJECTIVES: This study investigated the prevalence, incidence, and prognosis of cardiac amyloidosis (CA) in Korea. METHODS: This retrospective nationwide population-based study used the Health Insurance Review and Assessment Service databases between 2008 and 2020. All patients diagnosed with amyloidosis were included, and those with a diagnosis of heart failure or cardiomyopathy were classified as having CA. Both the special code for amyloidosis (V121), which enables coverage of medical expenses, and the corresponding International Classification of Diseases, 10th revision codes for amyloidosis (E850- E854, E858, E859) were used to improve the reliability of amyloidosis diagnosis. RESULTS: Among 2,239 patients with amyloidosis, 758 met the criteria for CA (mean age, 64.4±11.9 years; 59.1% male). The mean age of patients with CA increased from 59.5±14.7 years in 2009 to 68.1±13.9 years in 2020. The incidence and prevalence increased from 0.09 (95% confidence interval [CI], 0.06 to 0.12) to 0.22 (95% CI, 0.18 to 0.27) per 100,000 person-years and 0.20 (95% CI, 0.16 to 0.25) to 1.30 (95% CI, 0.12 to 0.42) per 100,000 persons, respectively (all p<0.001). Patients with light-chain CA showed similar trends. In-hospital mortality decreased from 17.3% (95% CI, 9.23 to 29.6) to 6.10% (95% CI, 4.21 to 8.48) between 2009 and 2020. While age-specific in-hospital mortality was significantly higher in patients aged ≥70 years (p=0.004), no significant age-specific difference in in-hospital mortality was observed in patients with CA aged <70 years (p=0.981). CONCLUSIONS The prevalence and incidence of CA have increased in Korea, predominantly affecting older individuals, particularly males. Notably, in-hospital mortality decreased significantly.

OBJECTIVES: This study investigated the prevalence, incidence, and prognosis of cardiac amyloidosis (CA) in Korea. METHODS: This retrospective nationwide population-based study used the Health Insurance Review and Assessment Service databases between 2008 and 2020. All patients diagnosed with amyloidosis were included, and those with a diagnosis of heart failure or cardiomyopathy were classified as having CA. Both the special code for amyloidosis (V121), which enables coverage of medical expenses, and the corresponding International Classification of Diseases, 10th revision codes for amyloidosis (E850- E854, E858, E859) were used to improve the reliability of amyloidosis diagnosis. RESULTS: Among 2,239 patients with amyloidosis, 758 met the criteria for CA (mean age, 64.4±11.9 years; 59.1% male). The mean age of patients with CA increased from 59.5±14.7 years in 2009 to 68.1±13.9 years in 2020. The incidence and prevalence increased from 0.09 (95% confidence interval [CI], 0.06 to 0.12) to 0.22 (95% CI, 0.18 to 0.27) per 100,000 person-years and 0.20 (95% CI, 0.16 to 0.25) to 1.30 (95% CI, 0.12 to 0.42) per 100,000 persons, respectively (all p<0.001). Patients with light-chain CA showed similar trends. In-hospital mortality decreased from 17.3% (95% CI, 9.23 to 29.6) to 6.10% (95% CI, 4.21 to 8.48) between 2009 and 2020. While age-specific in-hospital mortality was significantly higher in patients aged ≥70 years (p=0.004), no significant age-specific difference in in-hospital mortality was observed in patients with CA aged <70 years (p=0.981). CONCLUSIONS The prevalence and incidence of CA have increased in Korea, predominantly affecting older individuals, particularly males. Notably, in-hospital mortality decreased significantly.

OBJECTIVES: This study investigated the prevalence, incidence, and prognosis of cardiac amyloidosis (CA) in Korea. METHODS: This retrospective nationwide population-based study used the Health Insurance Review and Assessment Service databases between 2008 and 2020. All patients diagnosed with amyloidosis were included, and those with a diagnosis of heart failure or cardiomyopathy were classified as having CA. Both the special code for amyloidosis (V121), which enables coverage of medical expenses, and the corresponding International Classification of Diseases, 10th revision codes for amyloidosis (E850- E854, E858, E859) were used to improve the reliability of amyloidosis diagnosis. RESULTS: Among 2,239 patients with amyloidosis, 758 met the criteria for CA (mean age, 64.4±11.9 years; 59.1% male). The mean age of patients with CA increased from 59.5±14.7 years in 2009 to 68.1±13.9 years in 2020. The incidence and prevalence increased from 0.09 (95% confidence interval [CI], 0.06 to 0.12) to 0.22 (95% CI, 0.18 to 0.27) per 100,000 person-years and 0.20 (95% CI, 0.16 to 0.25) to 1.30 (95% CI, 0.12 to 0.42) per 100,000 persons, respectively (all p<0.001). Patients with light-chain CA showed similar trends. In-hospital mortality decreased from 17.3% (95% CI, 9.23 to 29.6) to 6.10% (95% CI, 4.21 to 8.48) between 2009 and 2020. While age-specific in-hospital mortality was significantly higher in patients aged ≥70 years (p=0.004), no significant age-specific difference in in-hospital mortality was observed in patients with CA aged <70 years (p=0.981). CONCLUSIONS The prevalence and incidence of CA have increased in Korea, predominantly affecting older individuals, particularly males. Notably, in-hospital mortality decreased significantly.

OBJECTIVES: This study investigated the prevalence, incidence, and prognosis of cardiac amyloidosis (CA) in Korea. METHODS: This retrospective nationwide population-based study used the Health Insurance Review and Assessment Service databases between 2008 and 2020. All patients diagnosed with amyloidosis were included, and those with a diagnosis of heart failure or cardiomyopathy were classified as having CA. Both the special code for amyloidosis (V121), which enables coverage of medical expenses, and the corresponding International Classification of Diseases, 10th revision codes for amyloidosis (E850- E854, E858, E859) were used to improve the reliability of amyloidosis diagnosis. RESULTS: Among 2,239 patients with amyloidosis, 758 met the criteria for CA (mean age, 64.4±11.9 years; 59.1% male). The mean age of patients with CA increased from 59.5±14.7 years in 2009 to 68.1±13.9 years in 2020. The incidence and prevalence increased from 0.09 (95% confidence interval [CI], 0.06 to 0.12) to 0.22 (95% CI, 0.18 to 0.27) per 100,000 person-years and 0.20 (95% CI, 0.16 to 0.25) to 1.30 (95% CI, 0.12 to 0.42) per 100,000 persons, respectively (all p<0.001). Patients with light-chain CA showed similar trends. In-hospital mortality decreased from 17.3% (95% CI, 9.23 to 29.6) to 6.10% (95% CI, 4.21 to 8.48) between 2009 and 2020. While age-specific in-hospital mortality was significantly higher in patients aged ≥70 years (p=0.004), no significant age-specific difference in in-hospital mortality was observed in patients with CA aged <70 years (p=0.981). CONCLUSIONS The prevalence and incidence of CA have increased in Korea, predominantly affecting older individuals, particularly males. Notably, in-hospital mortality decreased significantly.

Background and Objectives: Early diastolic mitral annular tissue (e’) velocity is a commonly used marker of left ventricular (LV) diastolic function. This study aimed to investigate the prognostic implications of e’ velocity in patients with mitral regurgitation (MR). Methods: This retrospective cohort study included 1,536 consecutive patients aged <65 years with moderate or severe chronic primary MR diagnosed between 2009 and 2018. The primary and secondary outcomes were all-cause and cardiovascular mortality, respectively.According to the current guidelines, the cut-off value of e’ velocity was defined as 7 cm/s. Results: A total of 404 individuals were enrolled (median age, 51.0 years; 64.1% male; 47.8% severe MR). During a median 6.0-year follow-up, there were 40 all-cause mortality and 16 cardiovascular deaths. Multivariate analysis revealed a significant association between e’ velocity and all-cause death (adjusted hazard ratio [aHR], 0.770; 95% confidence interval [CI], 0.634–0.935; p=0.008) and cardiovascular death (aHR, 0.690; 95% CI, 0.477–0.998;p=0.049). Abnormal e’ velocity (≤7 cm/s) independently predicted all-cause death (aHR, 2.467; 95% CI, 1.170–5.200; p=0.018) and cardiovascular death (aHR, 5.021; 95% CI, 1.189–21.211; p=0.028), regardless of symptoms, LV dimension and ejection fraction. Subgroup analysis according to sex, MR severity, mitral valve replacement/repair, and symptoms, showed no significant interactions. Including e’ velocity in the 10-year risk score improved reclassification for mortality (net reclassification improvement [NRI], 0.154; 95% CI, 0.308– 0.910; p<0.001) and cardiovascular death (NRI, 1.018; 95% CI, 0.680–1.356; p<0.001). Conclusions In patients aged <65 years with primary MR, e’ velocity served as an independent predictor of all-cause and cardiovascular deaths.

Background: Hand hygiene is considered the simplest and most cost-effective method of infection prevention. Regular observation and feedback on hand hygiene compliance are key strategies for its enhancement. This study evaluated the effectiveness of hand hygiene surveillance, including direct observation and feedback, by comprehensively analyzing the reported hand hygiene compliance within the Korean National Healthcare-Associated Infections Surveillance System from 2019 to 2022. Methods: Participating medical institutions included general hospitals and hospitals with infection control departments that consented to participate. Hand hygiene surveillance was conducted using direct observation. Collected data, including healthcare workers, clinical areas, hand hygiene moments, and hand hygiene compliance, were recorded to calculate hand hygiene compliance rates. Additionally, the volume of alcohol-based hand sanitizers used per patient per day was investigated as an indirect indicator of hand hygiene compliance. The study was conducted from July 2019 to December 2022. Results: Hand hygiene compliance increased from 87.2% in Q3 2019 to 89.9% in 2022. Nurses and medical technologists showed the highest compliance rates, whereas doctors showed the lowest compliance rates. Intensive care units excelled in compliance, whereas emergency de partments lagged. Compliance was highest after patient contact and lowest when the patient’s surroundings were touched. Larger hospitals consumed more alcohol-based hand sanitizers than smaller hospitals did. Conclusion This study confirmed an improvement in hand hygiene compliance through sustained surveillance, indicating its contribution not only to preventing infection transfer within healthcare facilities but also to fostering a culture of hand hygiene in the country.

Background/Aims: Cardiorespiratory fitness (CRF), as measured by maximal oxygen consumption (VO2max), is an important independent predictive factor of cardiovascular outcomes in patients with heart failure (HF). However, it is unclear whether conventional equations for estimating CRF are applicable to patients with HF with preserved ejection fraction (HFpEF). Methods: This study included 521 patients with HFpEF (EF ≥ 50%) whose CRF was directly measured by cardiopulmonary exercise test using a treadmill. We developed a new equation (Kor-HFpEF) for half of the patients in the HFpEF cohort (group A, n = 253) and validated it for the remaining half (group B, n = 268). The accuracy of the Kor-HFpEF equation was compared to that of the other equations in the validation group. Results: In the total HFpEF cohort, the directly measured VO2max was significantly overestimated by the FRIEND and ACSM equations (p < 0.001) and underestimated by the FRIEND-HF equation (p <0.001) (direct 21.2 ± 5.9 mL/kg/min; FRIEND 29.1 ± 11.8 mL/kg/min; ACSM 32.5 ± 13.4 mL/kg/min; FRIEND-HF 14.1 ± 4.9 mL/kg/min). However, the VO2max estimated by the Kor-HFpEF equation (21.3 ± 4.6 mL/kg/min) was similar to the directly measured VO2max (21.7 ± 5.9 mL/kg/min, p = 0.124), whereas the VO2max estimated by the other three equations was still significantly different from the directly measured VO2max in group B (all p < 0.001). Conclusions Traditional equations used to estimate VO2max were not applicable to patients with HFpEF. We developed and validated a new Kor-HFpEF equation for these patients, which had a high accuracy.

Given the higher prevalence of cardiac arrhythmias in individuals with diabetes, we investigated the relationship between cardiac arrhythmias and the incidence of gestational diabetes (GDM). This retrospective cohort study utilized data from the Korean Health Insurance Service database, encompassing 1,113,729 women who gave birth between January 2007 and December 2015. After excluding those who did not undergo National Health Screening tests within 1 year prior to pregnancy, those with multifetal pregnancies, and those diagnosed with diabetes, we analyzed 365,880 singleton pregnancies without a history of diabetes. Of these, 3,253 (0.9%) had cardiac arrhythmias, including premature extra beats, supraventricular tachyarrhythmias, and/or atrial flutter/fibrillation. GDM occurred in 31,938 (8.7%) subjects during pregnancy, and was more prevalent in women with cardiac arrhythmia than in those without (14.9 vs. 8.7%, p<0.001). In the multivariate analysis, the association between cardiac arrhythmia and GDM remained statistically significant (adjusted odds ratio, 1.78; 95% confidence interval, 1.61 to 1.97; p<0.001). Subgroup analysis revealed that the risk of GDM was consistently statistically significant in subjects with cardiac arrhythmia, regardless of age, body mass index, and the presence or absence of chronic hypertension. Therefore, cardiac arrhythmias before and during pregnancy appear to be associated with an increased risk of developing GDM.