The Third Nationwide Korean Heart Failure III Registry (KorHF III): The Study Design Paper

With advancements in both pharmacologic and non-pharmacologic treatments, significant changes have occurred in heart failure (HF) management. The previous Korean HF registries, namely the Korea Heart Failure Registry (KorHF-registry) and Korean Acute Heart Failure Registry (KorAHF-registry), no longer accurately reflect contemporary acute heart failure (AHF) patients. Our objective is to assess contemporary AHF patients through a nationwide registry encompassing various aspects, such as clinical characteristics, management approaches, hospital course, and long-term outcomes of individuals hospitalized for AHF in Korea. This prospective observational multicenter cohort study (KorHF III) is organized by the Korean Society of Heart Failure. We aim to prospectively enroll 7,000 or more patients hospitalized for AHF at 47 tertiary hospitals in Korea starting from March 2018. Eligible patients exhibit signs and symptoms of HF and demonstrate either lung congestion or objective evidence of structural or functional cardiac abnormalities in echocardiography, or isolated right-sided HF. Patients will be followed up for up to 5 years after enrollment in the registry to evaluate long-term clinical outcomes. KorHF III represents the nationwide AHF registry that will elucidate the clinical characteristics, management strategies, and outcomes of contemporary AHF patients in Korea.

Trial Registration

ClinicalTrials.gov Identifier: NCT04329234.

Impact of Cardiac Troponin Elevation on Mortality of Patients with Acute Heart Failure: Insights from the Korea Acute Heart Failure (KorAHF) Registry

We aimed to conduct the largest study evaluating the impact of cardiac troponin (TnI) status on mid- and long-term mortality in patients admitted for acute heart failure (AHF) as compared between patients with ischemic (IHF) vs. non-ischemic heart failure (non-IHF). Among 5625 patients from the Korea Acute Heart Failure (KorAHF) registry, 4396 eligible patients with TnI measurement were analyzed. The patients were included on admission with the diagnosis of AHF, and TnI level was measured on the day of admission. A TnI value of <0.05 ng/mL was considered normal. The patients were divided into four groups according to the etiology of heart failure and the status of TnI: non-IHF with normal TnI (n = 1009) vs. non-IHF with elevated TnI (n = 1665) vs. IHF with normal TnI (n = 258) vs. IHF with elevated TnI (n = 1464). The primary outcome was death from all causes according to the etiology (non-IHF vs. IHF) and TnI elevation during the entire follow-up period of 784 days (IQR 446−1116). Elevation of TnI was observed in 71.2% of all patients with AHF. Patients with IHF had higher all-cause mortality compared to those with non-IHF. Elevated TnI was associated with higher 90-day and post-90-day mortality in the non-IHF group. IHF as compared to non-IHF and elevation of TnI were independent predictors of mortality also in the adjustment analysis. In the IHF group, however, elevated TnI had a higher mortality with only 90-day follow-up (18.6% vs. 25.9%, log-rank p < 0.001), not in the post-90-day follow-up (31.1% vs. 32.5%, log-rank p = 0.799). In conclusion, elevated TnI in patients with heart failure is associated with increased all-cause mortality regardless of the etiology of HF. Elevation of TnI was associated to a higher post-90 day mortality in patients with non-IHF but not in patients with IHF.

Current status of heart failure: global and Korea

Heart failure (HF) is a condition in which the heart is unable to pump enough blood to meet the body's needs for blood and oxygen. Thus, HF is a grave disease with high morbidity and mortality. Because the prevalence of and exposure to the risk factors for HF increase with age, the prevalence of HF has been increasing in an aging society, including Korea. The vast advancement of medical and device therapy has improved the outcomes of HF, but significant residual risk still exists, and the benefit is confined to patients with reduced ejection fraction. Finding effective treatment for HF with preserved ejection fraction and identification of groups who benefit from drug and device therapy remain challenging. In this review, we illustrate the epidemiology, temporal trends, and current status of medical and device therapy, including heart transplantation, as well as emerging treatments for HF in Korea and worldwide.

Korean Guidelines for Diagnosis and Management of Chronic Heart Failure

The prevalence of heart failure (HF) is skyrocketing worldwide, and is closely associated with serious morbidity and mortality. In particular, HF is one of the main causes for the hospitalization and mortality in elderly individuals. Korea also has these epidemiological problems, and HF is responsible for huge socioeconomic burden. However, there has been no clinical guideline for HF management in Korea. 
The present guideline provides the first set of practical guidelines for the management of HF in Korea and was developed using the guideline adaptation process while including as many data from Korean studies as possible. The scope of the present guideline includes the definition, diagnosis, and treatment of chronic HF with reduced/preserved ejection fraction of various etiologies.

Clinical Characteristics and Outcome of Acute Heart Failure in Korea: Results from the Korean Acute Heart Failure Registry (KorAHF)

Background and Objectives

The burden of heart failure has increased in Korea. This registry aims to evaluate demographics, clinical characteristics, management, and long-term outcomes in patients hospitalized for acute heart failure (AHF).

Subjects and Methods

We prospectively enrolled a total of 5625 consecutive subjects hospitalized for AHF in one of 10 tertiary university hospitals from March 2011 to February 2014. Descriptive statistics were used to determine the baseline characteristics of the study population and to compare them with those from other registries.

Results

The mean age was 68.5±14.5 years, 53.2% were male, and 52.2% had de novo heart failure. The mean systolic and diastolic blood pressures were 131.2±30.3 mmHg and 78.6±18.8 mmHg at admission, respectively. The left ventricular ejection fraction was ≤40% in 60.5% of patients. Ischemia was the most frequent etiology (37.6%) and aggravating factor (26.3%). Angiotensin converting enzyme inhibitors/angiotensin receptor blockers, beta-blockers, and aldosterone antagonists were prescribed in 68.8%, 52.2%, and 46.6% of the patients at discharge, respectively. Compared with the previous registry performed in Korea a decade ago, extracorporeal membrane oxygenation (ECMO) and heart transplantation have been performed more frequently (ECMO 0.8% vs. 2.8%, heart transplantation 0.3% vs. 1.2%), and in-hospital mortality decreased from 7.6% to 4.8%. However, the total cost of hospital care increased by 40%, and one-year follow-up mortality remained high.

Conclusion

While the quality of acute clinical care and AHF-related outcomes have improved over the last decade, the long-term prognosis of heart failure is still poor in Korea. Therefore, additional research is needed to improve long-term outcomes and implement cost-effective care.

Temporal Trends of Hospitalized Patients with Heart Failure in Korea

Heart failure (HF) is an important cardiovascular disease because of its increasing prevalence, significant morbidity, high mortality and rapidly expanding health care costs. The number of HF patients is increasing worldwide and Korea is no exception. Temporal trends of four representative Korean hospitalized HF registries-the Hallym HF study, the Korean Multicenter HF study, the Korean Heart Failure (KorHF) registry and the Korean Acute Heart Failure (KorAHF) registry showed mild survival improvement reflecting overall HF patient care development in Korea despite the increased severity of enrolled patients with higher incidence of multiple comorbidities. Moreover, device therapies such as implantable cardioverter defibrillator and cardiac resynchronization therapy and definitive treatment such as heart transplantation have been increasing in Korea as well. To prevent HF burden increase, it is essential to set up long term effective prevention strategies for better control of ischemic heart disease, hypertension and diabetes, which might be risk factors for HF development. Moreover, proper HF guidelines, performance measures, and performance improvement programs might be necessary to limit HF burden as well.

Health-related quality of life in symptomatic postmyocardial infarction patients with left ventricular dysfunction

PURPOSE

Symptoms of postmyocardial infarction (post-MI) patients at risk for progression to heart failure are often ignored, and lack of symptom recognition or misinterpretation may diminish health-related quality of life (HRQoL). This study was conducted to evaluate the differences in HRQoL by symptom experience and determine factors that predict diminished HRQoL in post-MI patients.

METHODS

Using a descriptive correlational study design, post-MI patients with left ventricular dysfunction (ejection fraction < 50%) completed face-to-face interviews for symptoms, HRQoL, covariates including self-care compliance, New York Heart Association class, and demographic and clinical questionnaires.

RESULTS

A total of 105 post-MI patients participated (mean age 65 years, 79.0% male, mean ejection fraction 43.6%, New York Heart Association class III/IV 33.3%). Mean length of time after the cardiac event was 48 months. Patients reported four or more symptoms, with fatigue being the most common symptom (63.8%), followed by shortness of breath (56.2%), weakness (54.3%), and dizziness (51.4%). HRQoL was moderately poor, with a mean score of 44.38 ± 27.66. There was no significant relationship between self-care compliance and HRQoL. Patients who were female, with low monthly income, and had lower functional capacity and more symptoms had worse HRQoL, after controlling for age and length of time after the event (adjusted R(2) = 0.53, p < .001).

CONCLUSIONS

A need for transitional care that assists post-MI patients take an active involvement in symptom monitoring arises so that they can get into the system earlier and benefit from treatment, and eventually achieve desirable HRQoL.

Reliability and validity of the Korean version of the Minnesota Living with Heart Failure Questionnaire

OBJECTIVE

The aim of this study was to verify the reliability and validity of the Korean language version of the Minnesota Living with Heart Failure Questionnaire (MLHFQ) before using this version in clinical practice to assess the quality of care in patients with heart failure in a cardiology clinic.

METHODS

The Korean versions of the MLHFQ, 36-Item Short Form Health Survey, and Center for Epidemiologic Studies Depression Scale were administered to evaluate the psychometric properties among 154 patients with heart failure in a major cardiac center in Korea. Cardiac function was assessed by evaluating left ventricular ejection fraction values, N-terminal pro-brain natriuretic peptide levels, and New York Heart Association classifications.

RESULTS

The questionnaire content and construct validity were supported by factor analysis. Three factors explained 70.7% of the variance. Total and subtotal scales had correlations with the mental and physical component scores of the 36-Item Short Form Health Survey and Center for Epidemiologic Studies Depression Scale, supporting the convergent validity of the Korean version of the MLHFQ. We also found that the New York Heart Association classification was associated with the MLHFQ score. The internal consistency of both total and subtotal scales was greater than .80.

CONCLUSION

The Korean version of the MLHFQ demonstrated excellent psychometric properties. These results support the use of the MLHFQ in Korean patients with heart failure. Further studies are recommended to assess the responsiveness to change of the Korean version of the MLHFQ.

The relevance of the primary prevention criteria for implantable cardioverter defibrillator implantation in korean symptomatic severe heart failure patients

Background and Objectives

Implantable cardioverter defibrillator (ICD) therapy is recommended as the primary tool for prevention of sudden cardiac death (SCD) in symptomatic patients with severe left ventricular dysfunction. There is a paucity of information on whether this recommendation is appropriate for the Korean population with severe heart failure.

Subjects and Methods

The study group consisted of 275 consecutive patients (mean age 65 years, 71% male) who met the ICD implantation criteria for primary prevention (left ventricular ejection fraction ≤30% and New York Heart Association functional class II or III). We analyzed the clinical characteristics and outcomes of an ischemic cardiomyopathy (ICMP) group (n=131) and a non-ischemic cardiomyopathy (NICMP) group (n=144). The outcomes of these 2 groups were compared with the Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II) conventional and Defibrillators in the Non-ischemic Cardiomyopathy Treatment Evaluation (DEFINITE) standard therapy groups, respectively.

Results

Eighty patients (29%) died during a follow-up period of 40±17 months. The NICMP group had better all-cause mortality rates than the ICMP group (19% vs. 40%, p<0.001), however both groups had a similar incidence of SCD (7% vs. 10%, p=0.272). The 2-year all-cause mortality and SCD for the ICMP group were similar to those of the MADIT-II conventional therapy group (20% vs. 20%, 7% vs. 10%, respectively, all p>0.05). All-cause mortality and the incidence of SCD in the NICMP group were comparable to those of the DEFINITE standard therapy group (13% vs. 17%, 6% vs. 6%, respectively, all p>0.05).

Conclusion

Korean patients with severe heart failure in both the ICMP and NICMP groups had all-caused mortality and risk of SCD comparable to patients in the MADIT-II and DEFINITE standard therapy groups. Therefore, the primary prevention criteria for ICD implantation would be appropriate in both Korean ICMP and NICMP patients.

Symptom clusters predict event-free survival in patients with heart failure

BACKGROUND

Physical symptoms are likely to occur in clusters that may be associated with adverse outcome in patients with heart failure (HF). Despite the importance of early recognition of worsening symptoms in HF management, the impact of physical symptoms on adverse outcome has not been explored in the context of symptom clusters.

PURPOSE

The purposes of this study were to explore which physical symptom clusters occur in HF patients and to determine the impact of symptom clusters on event-free survival.

METHODS

A total of 421 patients (60% male; 62 [SD, 14] years; 72% New York Heart Association class II/III) completed the modified Memorial Symptom Assessment Scale-Heart Failure to measure physical symptoms during an index hospitalization in Seoul, Korea. Times to first event of cardiac rehospitalization and cardiac death were collected for 12 months after discharge and confirmed by review of hospital records. An agglomerative hierarchical clustering approach with Ward's method was used to identify symptom clusters. Hierarchical Cox hazard regression was used to determine the impact of symptom clusters on cardiac rehospitalization and cardiac mortality.

RESULTS

Two distinct symptom clusters, the dyspneic and the weary symptom clusters, occurred in patients with HF. Shortness of breath, difficulty breathing when lying flat, and waking up breathless at night comprised the dyspneic symptom cluster. Lack of energy, lack of appetite, and difficulty sleeping comprised the weary symptom cluster. In hierarchical Cox hazard regression, elevated distress from the weary symptom cluster independently predicted cardiac rehospitalization (hazard ratio, 1.45; 95% confidence interval, 1.09-1.93), and increased distress from the dyspneic symptom cluster independently predicted cardiac mortality (hazard ratio, 2.00; 95% confidence interval, 1.16-3.34).

CONCLUSION

The weary and the dyspneic symptom clusters predicted cardiac rehospitalization and cardiac mortality, respectively. Patient education for self-monitoring of symptoms should focus on symptom clusters rather than single symptom.

Relationship of depressive symptoms to the impact of physical symptoms on functional status in women with heart failure

BACKGROUND

Among patients with heart failure, women have worse functional status than do men, but little research has focused on determining factors that influence functional status in either sex.

OBJECTIVES

To compare factors that influence functional status in men and women with heart failure and to test whether depressive symptoms mediate the relationship between physical symptoms and functional status.

METHODS

A cross-sectional, descriptive study design was used. A total of 231 patients, 133 men and 98 women, were recruited from an inpatient heart failure clinic in South Korea. Functional status (the Korean Activity Scale/Index), physical symptoms (the Symptom Status Questionnaire), depressive symptoms (the Beck Depression Inventory), and situational factors (living status, socioeconomic status) were measured. Hierarchical multiple regression and mediation analysis were used for data analysis.

RESULTS

Women (mean score, 24.5; SD, 17.3) had worse functional status than did men (mean score, 31.9; SD, 20.1; P = .004). Dyspnea on exertion (beta = -0.16), ankle swelling (beta = -0.19), fatigue (beta = -0.20), and depressive symptoms (beta = -0.19) were independently associated with functional status in women, whereas only dyspnea on exertion (beta = -0.30) influenced functional status of men in hierarchical multiple regression analysis. Mediation analysis indicated that depressive symptoms mediated the relationship between physical symptoms and functional status in women with heart failure, but not in men.

CONCLUSIONS

Distinct physical and psychological symptoms influence functional status in women with heart failure. A systematic multidimensional intervention may be required to target depressive symptoms to improve functional status in women with heart failure.

Adherence to the low-sodium diet plays a role in the interaction between depressive symptoms and prognosis in patients with heart failure

BACKGROUND

Although a low-sodium diet (LSD) is important in self-management of patients with heart failure (HF), the impact of LSD on event-free survival has not been investigated. Depressive symptoms predict worse event-free survival, in part, by affecting adherence to self-management. However, there are few investigations of the relationship among depressive symptoms, adherence to the LSD, and event-free survival.

PURPOSE

The purpose of this study was to determine the relationships among adherence to the LSD, depressive symptoms, and event-free survival.

METHODS

A total of 254 patients (57% male, 62 ± 14 years, 52% New York Heart Association class III/IV, ejection fraction of 36% ± 14%) were recruited from outpatient HF clinics in Korea. Twenty-four-hour urinary sodium excretion was collected as an indicator of patient adherence to the LSD. Patients were grouped based on the cut point of 3 g of urinary sodium excretion. Depressive symptoms were assessed by the Korean version of Beck Depression Inventory, and patients were split into 2 groups at the cutoff of the Korean version of Beck Depression Inventory. Event-free survival for 12 months was determined by medical records. Hierarchical Cox proportional hazards regression was used to determine the association of depressive symptoms and adherence to 3-g sodium intake on event-free survival.

RESULTS

After controlling for age, sex, etiology of HF, body mass index, New York Heart Association class, ejection fraction, N-terminal B-type natriuretic peptide, and total comorbidity score, nonadherence to 3-g sodium intake (hazard ratio = 1.56, 95% confidence interval = 1.05-2.32) and depressive symptoms (hazard ratio = 2.21, 95% confidence interval = 1.47-3.33) independently predicted event-free survival. Patients with sodium intake higher than 3 g and with depressive symptoms demonstrated a 3.7 times higher risk for cardiac events compared with patients with sodium intake lower than 3 g and without depressive symptoms (P < .001).

CONCLUSION

Improvement of adherence to the LSD and treatment for depressive symptoms could improve event-free survival.

Depressive symptoms increase risk of rehospitalisation in heart failure patients with preserved systolic function

AIMS

To examine the impact of depressive symptoms on rehospitalisation for heart failure exacerbation in patients with preserved systolic function.

BACKGROUND

Depressive symptoms associated with higher risk of rehospitalisation have been primarily demonstrated in heart failure patients with systolic dysfunction (ejection fraction <40%) and the factors influencing rehospitalisation of patients with preserved systolic function (ejection fraction > or =40%) remain unclear.

DESIGN

A prospective, descriptive study design was used.

METHODS

The following baseline data were collected from 165 patients with preserved systolic function during an index hospitalisation for heart failure in South Korea: age, gender, body mass index, New York Heart Association functional class, the ratio of mitral velocity to early diastolic velocity of the mitral annulus, comorbidities, history of prior admission and depressive symptoms. Patients were followed monthly for six months after discharge to collect date on all rehospitalisation for heart failure exacerbation. Hierarchical Cox proportional hazards regression was used to identify independent predictors of rehospitalisation. Kaplan-Meier survival curves with log-rank test were used to determine differences in time to rehospitalisation according to severity of depressive symptoms.

RESULTS

Almost half of the patients (48%) had moderate to severe depressive symptoms. The ratio of mitral velocity to early diastolic velocity of the mitral annulus (hazard ratio = 1.06, 95% confidence interval = 1.02-1.10) and depressive symptoms (hazard ratio = 1.05, 95% confidence interval = 1.02-1.08) independently predicted rehospitalisation after controlling for other risk factors. Moderate and severe depressive symptoms were associated with both a higher rate and shorter time to rehospitalisation.

CONCLUSIONS

Moderate to severe depressive symptoms predict early rehospitalisation for heart failure exacerbations in patients with preserved systolic function.

RELEVANCE TO CLINICAL PRACTICE

Nurses should assess for depressive symptoms in patients with heart failure and refer those with depressive symptoms for treatment to improve outcomes.