Acute Heart Failure Syndromes in Patients With Coronary Artery Disease

Risk factors and prognosis of perioperative acute heart failure in elderly patients with hip fracture: case-control studies and cohort study

BACKGROUND

Elderly patients with hip fracture who develop perioperative acute heart failure (AHF) have a poor prognosis. The aim of the present study is to investigate the potential risks of AHF in elderly hip-fracture patients in the postoperative period and to evaluate the prognostic significance of AHF.

METHODS

A retrospective analysis was conducted on hip fracture patients at the Third Hospital of Hebei Medical University, who were continuously in hospital from September 2018 to August 2020. To identify independent risk factors for AHF in elderly patients with hip fracture, univariate and multivariate Logistic regression analysis was employed. The Kaplan-Meier survival curve illustrated the relationship between all-cause mortality in the AHF and non-AHF groups. An assessment of the correlation between baseline factors and all-cause mortality was conducted by means of univariable and multivariable Cox proportional hazards analysis.

RESULTS

We eventually recruited 492 patients,318 of whom were in the AHF group. Statistical significance was found between the two groups for age group, concomitant coronary heart disease, COPD, haemoglobin level below 100 g/L on admission, albumin level below 40 g/L on admission, and increased intraoperative blood loss. Age over 75, concomitant coronary artery disease, hemoglobin level below 100 g/L and albumin level below 40 g/L on admission were independent risk factors for AHF in older hip fracture patients. The AHF group exhibited a higher incidence of perioperative complications, such as anemia, cardiovascular issues, and stress hyperglycemia, as well as all-cause mortality. Based on our COX regression analysis, we have identified that the main risk factors for all-cause mortality in AHF patients are concomitant coronary heart disease, absence of pulmonary infection, absence of diabetes, absence of cancer, and absence of urinary tract infection.

CONCLUSION

Enhancing hip fracture prevention for AHF is particularly important. It is crucial to make informed decisions to avoid poor prognoses. Patients whose age over 75 years old, concomitant coronary heart disease, hemoglobin < 100 g/L and album< 40 g/L on admission are more likely to develop perioperative AHF. To avert complications and potential fatalities, patients with AHF must receive appropriate care during the perioperative period.

The therapeutic value of bifidobacteria in cardiovascular disease

There has been an increase in cardiovascular morbidity and mortality over the past few decades, making cardiovascular disease (CVD) the leading cause of death worldwide. However, the pathogenesis of CVD is multi-factorial, complex, and not fully understood. The gut microbiome has long been recognized to play a critical role in maintaining the physiological and metabolic health of the host. Recent scientific advances have provided evidence that alterations in the gut microbiome and its metabolites have a profound influence on the development and progression of CVD. Among the trillions of microorganisms in the gut, bifidobacteria, which, interestingly, were found through the literature to play a key role not only in regulating gut microbiota function and metabolism, but also in reducing classical risk factors for CVD (e.g., obesity, hyperlipidemia, diabetes) by suppressing oxidative stress, improving immunomodulation, and correcting lipid, glucose, and cholesterol metabolism. This review explores the direct and indirect effects of bifidobacteria on the development of CVD and highlights its potential therapeutic value in hypertension, atherosclerosis, myocardial infarction, and heart failure. By describing the key role of Bifidobacterium in the link between gut microbiology and CVD, we aim to provide a theoretical basis for improving the subsequent clinical applications of Bifidobacterium and for the development of Bifidobacterium nutritional products.

Identification of hub genes and key signaling pathways by weighted gene co-expression network analysis for human aortic stenosis and insufficiency

Background

Human aortic valve stenosis (AS) and insufficiency (AI) are common diseases in aging population. Identifying the molecular regulatory networks of AS and AI is expected to offer novel perspectives for AS and AI treatment.

Methods

Highly correlated modules with the progression of AS and AI were identified by weighted genes co-expression network analysis (WGCNA). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed by the clusterProfiler program package. Differentially expressed genes (DEGs) were identified by the DESeqDataSetFromMatrix function of the DESeq2 program package. The protein-protein interaction (PPI) network analyses were implemented using the STRING online tool and visualized with Cytoscape software. The DEGs in AS and AI groups were overlapped with the top 30 genes with highest connectivity to screen out ten hub genes. The ten hub genes were verified by analyzing the data in high throughput RNA-sequencing dataset and real-time PCR assay using AS and AI aortic valve samples.

Results

By WGCNA algorithm, 302 highly correlated genes with the degree of AS, degree of AI, and heart failure were identified from highly correlated modules. GO analyses showed that highly correlated genes had close relationship with collagen fibril organization, extracellular matrix organization and extracellular structure organization. KEGG analyses also manifested that protein digestion and absorption, and glutathione metabolism were probably involved in AS and AI pathological courses. Moreover, DEGs were picked out for 302 highly correlated genes in AS and AI groups relative to the normal control group. The PPI network analyses indicated the connectivity among these highly correlated genes. Finally, ten hub genes (CD74, COL1A1, TXNRD1, CCND1, COL5A1, SERPINH1, BCL6, ITGA10, FOS, and JUNB) in AS and AI were found out and verified.

Conclusion

Our study may provide the underlying molecular targets for the mechanism research, diagnosis, and treatment of AS and AI in the future.

Coronary Artery Disease and Heart Failure With Preserved Ejection Fraction: The ARIC Study

Background Whether coronary artery disease (CAD) is a significant risk factor for heart failure (HF) with preserved ejection fraction (HFpEF) is unclear. Methods and Results Among 9902 participants in the ARIC (Atherosclerosis Risk in Communities) study, we assessed the association of incident CAD with subsequent incident HFpEF (left ventricular ejection fraction [≥50%]) and HF with reduced ejection fraction (HFrEF; left ventricular ejection fraction <50%) using survival models with time-updated variables. We also assessed the extent to which echocardiographic correlates of prevalent CAD account for the relationship between CAD and incident HFpEF. Over 13-year follow-up, incident CAD developed in 892 participants and 178 subsequently developed HF (86 HFrEF, 71 HFpEF). Incident HFrEF and HFpEF risk were both greatest early after the CAD event. At >1 year post-CAD event, adjusted incidence of HFrEF and HFpEF were similar (7.2 [95% CI, 5.2-10.0] and 6.7 [4.8-9.2] per 1000 person-years, respectively) and CAD remained predictive of both (HFrEF: hazard ratio, 2.76 [95% CI, 1.99-3.84]; HFpEF: 1.85 [1.35-2.54]) after adjusting for demographics and common comorbidities. Among 4779 HF-free participants at Visit 5 (2011-2013), the 490 with prevalent CAD had lower left ventricular ejection fraction and higher left ventricular mass index, E/e', and left atrial volume index (all P<0.01). The association of prevalent CAD with incident HFpEF post-Visit 5 was not significant after adjusting for echocardiographic measures, with the greatest attenuation observed for left ventricular diastolic function. Conclusions CAD is a significant risk factor for incident HFpEF after adjustment for demographics and common comorbidities. This relationship is partially accounted for by echocardiographic alterations, particularly left ventricular diastolic function.

Temporal trends in characteristics and outcome of heart failure patients with and without significant coronary artery disease

AIMS

Ischaemic coronary artery disease (CAD) remains the leading cause of mortality globally due to sudden death and heart failure (HF). Invasive coronary angiography (CAG) is the gold standard for evaluating the presence and severity of CAD. Our objective was to assess temporal trends in CAG utilization, patient characteristics, and prognosis in HF patients undergoing CAG at a national level.

METHODS AND RESULTS

We used data from the Swedish Coronary Angiography and Angioplasty Registry. Data on all patients undergoing CAG for HF indication in Sweden between 2000 and 2018 were collected and analysed. Long-term survival was estimated with multivariable Cox proportional hazards regression adjusted for differences in patient characteristics. In total, 22 457 patients (73% men) with mean age 64.2 ± 11.3 years were included in the study. The patients were increasingly older with more comorbidities over time. The number of CAG specifically for HF indication increased by 5.5% per calendar year (P < 0.001). No such increase was seen for indications angina pectoris and ST-elevation myocardial infarction. A normal CAG or non-obstructive CAD was reported in 63.2% (HF-NCAD), and 36.8% had >50% diameter stenosis in one or more coronary arteries (HF-CAD). The median follow-up time was 3.6 years in HF-CAD and 5 years in HF-NCAD. Age and sex-adjusted survival improved linearly by 1.3% per calendar year in all patients. Compared with HF-NCAD, long-term mortality was higher in HF-CAD patients. The risk of death increased with the increasing severity of CAD. Compared with HF-NCAD, the risk estimate in patients with a single-vessel disease was higher [hazard ratio (HR) 1.3; 95% confidence interval (CI) 1.20-1.41; P < 0.001], a multivessel disease without the involvement of left main coronary artery (HR 1.72; 95% CI 1.58-1.88; P < 0.001), and with left main disease (HR 2.02; 95% CI 1.88-2.18; P < 0.001). The number of HF patients undergoing revascularization with percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) increased by 7.5% (P < 0.001) per calendar year. The majority (53.4%) of HF-CAD patients were treated medically, while a minority (46.6%) were referred for revascularization with PCI or CABG. Compared with patients treated with PCI, the proportion of patients treated medically or with CABG decreased substantially (P < 0.001).

CONCLUSIONS

Over 18 years, the number of patients with HF undergoing CAG has increased substantially. Expanded utilization of CAG increased the number of HF patients treated with percutaneous coronary intervention and coronary artery bypass surgery. Long-term survival improved in all HF patients despite a steady increase of elderly patients with comorbidities.

Platelet-to-hemoglobin ratio as a valuable predictor of long-term all-cause mortality in coronary artery disease patients with congestive heart failure

BACKGROUND

The platelet-to-hemoglobin ratio (PHR) has emerged as a prognostic biomarker in coronary artery disease (CAD) patients after PCI but not clear in CAD complicated with congestive heart failure (CHF). Hence, we aimed to assess the association between PHR and long-term all-cause mortality among CAD patients with CHF.

METHODS

Based on the registry at Guangdong Provincial People's Hospital in China, we analyzed data of 2599 hospitalized patients who underwent coronary angiography (CAG) and were diagnosed with CAD complicated by CHF from January 2007 to December 2018. Low PHR was defined as ˂ 1.69 (group 1) and high PHR as ≥ 1.69 (group 2). Prognosis analysis was performed using Kaplan-Meier method. To assess the association between PHR and long-term all-cause mortality, a Cox-regression model was fitted.

RESULTS

During a median follow-up of 5.2 (3.1-7.8) years, a total of 985 (37.9%) patients died. On the Kaplan-Meier analysis, patients in high PHR group had a worse prognosis than those in low PHR group (log-rank, p = 0.0011). After adjustment for confounders, high PHR was correlated with an increased risk of long-term all-cause mortality in CAD patients complicated with CHF. (adjusted hazard ratio [aHR], 1.31; 95% confidence interval [CI], 1.13-1.52, p < 0.0001).

CONCLUSION

Elevated PHR is correlated with an increased risk of long-term all-cause mortality in CAD patients with CHF. These results indicate that PHR may be a useful prognostic biomarker for this population. Meanwhile, it is necessary to take effective preventive measures to regulate both hemoglobin levels and platelet counts in this population.

Coronary angiography in patients with acute heart failure: from the KCHF registry

Aims

Little is known about the characteristics and outcomes of patients who undergo coronary angiography during heart failure (HF) hospitalization, as well as those with coronary stenosis, and those who underwent coronary revascularization.

Methods and results

We analysed 2163 patients who were hospitalized for HF without acute coronary syndrome or prior HF hospitalization. We compared patient characteristics and 1 year clinical outcomes according to (i) patients with versus without coronary angiography, (ii) patients with versus without coronary stenosis, and (iii) patients with versus without coronary revascularization. The primary outcome measure was the composite of all‐cause death or HF hospitalization. Coronary angiography was performed in 37.0% of patients. In the multivariable logistic regression analysis, factors independently associated with coronary angiography were age < 80 years [adjusted odds ratio (OR) = 1.76, 95% confidence interval (CI) = 1.41–2.20, P < 0.001], men (adjusted OR = 1.28, 95% CI = 1.03–1.59, P = 0.02), diabetes (adjusted OR = 1.27, 95% CI = 1.02–1.60, P = 0.04), no atrial fibrillation or flutter (adjusted OR = 1.45, 95% CI = 1.17–1.82, P < 0.001), no prior device implantation (adjusted OR = 1.81, 95% CI = 1.13–2.91, P = 0.01), current smoking (adjusted OR = 1.40, 95% CI = 1.05–1.87, P = 0.02), no cognitive dysfunction (adjusted OR = 1.90, 95% CI = 1.34–2.69, P < 0.001), ambulatory status (adjusted OR = 2.89, 95% CI = 2.03–4.10, P < 0.001), HF with reduced ejection fraction (adjusted OR = 1.55, 95% CI = 1.24–1.93, P < 0.001), estimated glomerular filtration rate ≥ 30 mL/min/1.73 m² (adjusted OR = 1.93, 95% CI = 1.45–2.58, P < 0.001), no anaemia (adjusted OR = 1.27, 95% CI = 1.02–1.59, P = 0.04), and no prescription of β‐blockers prior to admission (adjusted OR = 1.32, 95% CI = 1.03–1.68, P = 0.03). Patients who underwent coronary angiography had a lower risk of the primary outcome [adjusted hazard ratio (HR) = 0.70, 95% CI = 0.58–0.85, P < 0.001]. Among the patients who underwent coronary angiography, those with coronary stenosis (38.9%) did not have lower risk of the primary outcome measure than those without coronary stenosis (adjusted HR = 0.93, 95% CI = 0.65–1.32, P = 0.68). Among the patients with coronary stenosis, those with coronary revascularization (54.3%) did not have higher risk of the primary outcome measure than those without coronary revascularization (adjusted HR = 1.36, 95% CI = 0.84–2.21, P = 0.22).

Conclusions

In patients with acute HF, patients who underwent coronary angiography had a lower risk of clinical outcomes and were significantly different from those who did not undergo coronary angiography.

Established and Emerging Pharmacological Therapies for Post-Myocardial Infarction Patients with Heart Failure: a Review of the Evidence

After an episode of myocardial infarction (MI), patients remain at risk for recurrent ischemic events, heart failure (HF), and sudden death. Post-MI patients with left ventricular systolic dysfunction (LVSD) have an even greater risk of mortality and morbidity. Randomized clinical trials that included post-MI patients with LVSD have demonstrated that pharmacologic therapies aimed at preventing post-MI remodeling with neurohormonal antagonists can significantly improve short- and long-term outcomes, including death, reinfarction, and worsening HF. Recent trials have also demonstrated benefits in terms of cardiovascular event reduction with effective antithrombotic therapies and cholesterol-lowering agents in post-MI setting, especially in patients at very high risk such as those with LVSD. This paper reviews clinical trials that included post-MI patients with LVSD, with or without signs and symptoms of HF, assessing the efficacy of established and emerging pharmacological therapies.

High particulate matter 2.5 levels and ambient temperature are associated with acute lung edema in patients with nondialysis Stage 5 chronic kidney disease

BACKGROUND

Numerous studies have shown that exposure to air pollution, especially particulate matter (PM) with a diameter <2.5 μm (PM2.5), was associated with various diseases. We tried to determine the impact of PM2.5 and other weather factors on acute lung edema in patients with Stage 5 nondialysis chronic kidney disease (CKD Stage 5-ND).

METHODS

In total, 317 CKD Stage 5-ND (estimated glomerular filtration rate 6.79 ± 4.56 mL/min) patients residing in central Taiwan who developed acute lung edema and initiated long-term dialysis were included in this case-crossover study. Pearson's correlation test was used to examine the relationship of acute lung edema cases with PM2.5 levels and ambient temperature separately.

RESULTS

The average PM2.5 level within the 7-day period correlated with acute lung edema incidence in the fall [adjusted odds ratio (OR) 3.23, P = 0.047] and winter (adjusted OR 1.99, P < 0.001). In winter, even a 3-day exposure to PM2.5 was associated with increased risk (adjusted OR 1.55, P < 0.001). The average temperatures within 3 days in spring and summer were correlated positively with the risk (adjusted OR 2.77 P < 0.001 and adjusted OR 2.72, P < 0.001, respectively). In the fall and winter, temperatures were correlated negatively with the risk (adjusted OR 0.36, P < 0.001 and adjusted OR 0.54, P < 0.001, respectively).

CONCLUSIONS

A high PM2.5 level was associated with an increased risk of acute lung edema. High ambient temperature in hot seasons and low ambient temperature in cold seasons were also associated with increased risk. It is essential to educate these patients to avoid areas with severe air pollution and extreme ambient temperature.

Isolation of Cardiomyocytes Undergoing Mitosis With Complete Cytokinesis

RATIONALE

Adult human cardiomyocytes do not complete cytokinesis despite passing through the S-phase of the cell cycle. As a result, polyploidization and multinucleation occur. To get a deeper understanding of the mechanisms surrounding division of cardiomyocytes, there is a crucial need for a technique to isolate cardiomyocytes that complete cell division/cytokinesis.

OBJECTIVE

Markers of cell cycle progression based on DNA content cannot distinguish between mitotic cardiomyocytes that fail to complete cytokinesis from those cells that undergo true cell division. With the use of molecular beacons (MBs) targeting specific mRNAs, we aimed to identify truly proliferative cardiomyocytes derived from human induced pluripotent stem cells.

METHODS AND RESULTS

Fluorescence-activated cell sorting combined with MBs was performed to sort cardiomyocyte populations enriched for mitotic cells. Expressions of cell cycle specific genes were confirmed by means of reverse transcription-quantitative polymerase chain reaction and single-cell RNA sequencing (scRNA-seq) combined with gene signatures of cell cycle progression. We characterized the sorted groups by proliferation assays and time-lapse microscopy which confirmed the proliferative advantage of MB-positive cell populations relative to MB-negative and G2/M populations. Gene expression analysis revealed that the MB-positive cardiomyocyte subpopulation exhibited patterns consistent with the processes of nuclear division, chromosome segregation, and transition from M to G1 phase. The use of dual-MBs targeting CDC20 and SPG20 mRNAs enabled the enrichment of cytokinetic events (CDC20^highSPG20^high). Interestingly, cells that did not complete cytokinesis and remained binucleated were found to be CDC20^lowSPG20^high while polyploid cardiomyocytes that replicated DNA but failed to complete karyokinesis were found to be CDC20^lowSPG20^low.

CONCLUSIONS

This study demonstrates a novel alternative to existing DNA content-based approaches for sorting cardiomyocytes with true mitotic potential that can be used to study the unique dynamics of cardiomyocyte nuclei during mitosis. Our technique for sorting live cardiomyocytes undergoing cytokinesis would provide a basis for future studies to uncover mechanisms underlying the development and regeneration of heart tissue.

Diagnosis of Acute Heart Failure in the Emergency Department: An Evidence-Based Review

Heart failure is a common presentation to the emergency department (ED), which can be confused with other clinical conditions. This review provides an evidence-based summary of the current ED evaluation of heart failure. Acute heart failure is the gradual or rapid decompensation of heart failure, resulting from either fluid overload or maldistribution. Typical symptoms can include dyspnea, orthopnea, or systemic edema. The physical examination may reveal pulmonary rales, an S3 heart sound, or extremity edema. However, physical examination findings are often not sensitive or specific. ED assessments may include electrocardiogram, complete blood count, basic metabolic profile, liver function tests, troponin, brain natriuretic peptide, and a chest radiograph. While often used, natriuretic peptides do not significantly change ED treatment, mortality, or readmission rates, although they may decrease hospital length of stay and total cost. Chest radiograph findings are not definitive, and several other conditions may mimic radiograph findings. A more reliable modality is point-of-care ultrasound, which can facilitate the diagnosis by assessing for B-lines, cardiac function, and inferior vena cava size. These modalities, combined with clinical assessment and gestalt, are recommended.

Heart failure admission across glomerular filtration rate categories in a community cohort of 125,053 individuals over 60 years of age

A reduced estimated glomerular filtration rate (eGFR) has been described as a predictor of heart failure (HF). However, the increased risk across eGFR categories has not been fully evaluated, which is especially relevant in older individuals in whom both the prevalence of HF and decreased eGFR are higher. Furthermore, this association has not been studied in Mediterranean populations, where coronary heart disease (CHD), a frequent cause of HF, has a low prevalence. We performed a retrospective cohort study using the electronic medical records from primary and hospital settings in northeastern Spain. We included 125,053 individuals ≥60 years old with the determination of creatinine and without diagnosis or previous admission due to HF. The eGFR was calculated according to the CKD-EPI formula and classified by clinical categories. The association between eGFR, as a continuous and categorical variable, and the risk of admission due to HF was assessed by Cox proportional risk analysis, considering death as a competitive risk. During a median follow-up of 38.8 months, 2,176 individuals (1.74%) were hospitalized due to HF. The unadjusted admission rates were 4.02, 13.0, 26.0, and 48.6 per 1000 person-years for eGFR > 60, 45-59, 30-44, and 15-29 ml/min/1.73 m², respectively. The corresponding hazard ratios (95% confidence interval; reference eGFR 60-89) were 1.38 (95% CI 1.23-1.55), 2.02 (95% CI 1.76-2.32) and 3.46 (95% CI 2.78-4.31). In this Mediterranean community-based cohort of individuals ≥60 years old without previous HF, the risk of admission due to HF gradually increased with decreasing eGFR.

Dysrhythmias and heart failure complicating acute myocardial infarction: An emergency medicine review

INTRODUCTION

Patients with acute myocardial infarction (AMI) may suffer several complications after the acute event, including dysrhythmias and heart failure (HF). These complications place patients at risk for morbidity and mortality.

OBJECTIVE

This narrative review evaluates literature and guideline recommendations relevant to the acute emergency department (ED) management of AMI complicated by dysrhythmia or HF, with a focus on evidence-based considerations for ED interventions.

DISCUSSION

Limited evidence exists for ED management of dysrhythmias in AMI due to relatively low prevalence and frequent exclusion of patients with active cardiac ischemia from clinical studies. Management decisions for bradycardia in the setting of AMI are determined by location of infarction, timing of the dysrhythmia, rhythm assessment, and hemodynamic status of the patient. Atrial fibrillation is common in the setting of AMI, and caution is warranted in acute rate control for rapid ventricular rate given the possibility of compensation for decreased ventricular function. Regular wide complex tachycardia in the setting of AMI should be managed as ventricular tachycardia with electrocardioversion in the majority of cases. Management directed towards HF from left ventricular dysfunction in AMI consists of noninvasive positive pressure ventilation, nitroglycerin therapy, and early cardiac catheterization. Norepinephrine is the first line vasopressor for patients with cardiogenic shock and hypoperfusion on clinical examination. Early involvement of a multi-disciplinary team is recommended when caring for patients in cardiogenic shock.

CONCLUSIONS

This review discusses considerations of ED management of dysrhythmias and HF associated with AMI.

Multimodality imaging in ischaemic heart failure

In heart failure, extensive evaluation with modern non-invasive imaging modalities is needed to assess causes, pathophysiology, and haemodynamics, to determine prognosis and consider therapeutic options. This systematic evaluation includes a stepwise assessment of left ventricular size and function, the presence and severity of coronary artery disease, mitral regurgitation, pulmonary hypertension, right ventricular dilation and dysfunction, and tricuspid regurgitation. Based on this imaging-derived information, the need for specific therapies besides optimised medical therapy can be determined. The need for revascularisation, implantation of an implantable cardiac defibrillator, and mitral or tricuspid valve repair or replacement, can be (partially) guided by non-invasive imaging. Importantly, randomised controlled trials on the use of non-inasive imaging to guide therapy are scarce in this field and most non-pharmacological therapies are based on expert-consensus, but whenever trials are available, they will be addressed in this paper.

Beta-blockers for post-acute coronary syndrome mid-range ejection fraction: a nationwide retrospective study

BACKGROUND

Patients with mid-range ejection fraction (40-49%) are in focus due to the newly defined entity of heart failure with mid-range ejection fraction. Acute coronary syndromes are a major aetiology for heart failure with mid-range ejection fraction. We aim to evaluate which therapeutic decisions are associated with inhospital survival benefit in post-acute coronary syndrome patients categorised according to the ejection fraction.

METHODS AND RESULTS

The authors analysed a cohort of a multicentre national registry enrolling acute coronary syndrome patients between 2010 and 2016, classified according to their ejection fraction before hospital discharge. Patients with previously known heart failure or with no ejection fraction evaluation were excluded. A total of 9429 patients were included and categorised in three groups: (a) ejection fraction of 50% or greater (n=6113, 65%); (b) ejection fraction of 40-49% (n=1926, 20%); and (c) ejection fraction less than 40% (n=1390, 15%). The primary endpoint was inhospital mortality. To eliminate confounding factors, a multivariate logistic regression analysis was conducted, including acute coronary syndrome type, baseline characteristics, pharmacological treatment, clinical data, laboratory data and coronary anatomy when known. The overall inhospital mortality was 2.8% (n=263): 0.9% (n=53) in group 1, 2.4% (n=37) in group 2 and 11.4% (n=159) in group 3. After multivariate analysis, an invasive strategy had a positive impact in all groups, inhospital beta-blocker administration had a positive impact for groups 2 and 3, and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker and spironolactone had a positive impact on group 3.

CONCLUSION

Post-acute coronary syndrome mid-range ejection fraction patients represent an intermediate risk group in which beta-blocker administration was associated with inhospital survival benefit. An invasive strategy was a survival predictor for all groups, regardless of ejection fraction category.

KSHF Guidelines for the Management of Acute Heart Failure: Part I. Definition, Epidemiology and Diagnosis of Acute Heart Failure

The prevalence of heart failure (HF) is on the rise due to the aging of society. Furthermore, the continuous progress and widespread adoption of screening and diagnostic strategies have led to an increase in the detection rate of HF, effectively increasing the number of patients requiring monitoring and treatment. Because HF is associated with substantial rates of mortality and morbidity, as well as high socioeconomic burden, there is an increasing need for developing specific guidelines for HF management. The Korean guidelines for the diagnosis and management of chronic HF were introduced in March 2016. However, chronic and acute heart failure (AHF) represent distinct disease entities. Here, we introduce the Korean guidelines for the management of AHF with reduced or preserved ejection fraction. Part I of this guideline covers the definition, epidemiology, and diagnosis of AHF.

Identifying and Managing Hibernating Myocardium: What's New and What Remains Unknown?

PURPOSE OF REVIEW

Hibernation is an important and reversible cause of myocardial dysfunction in ischaemic heart failure.

RECENT FINDINGS

Hibernation is an adaptive process that promotes myocyte survival over maintaining contractile function. It is innate to mammalian physiology, sharing features with physiological hibernation in other species. Advanced imaging methods have reasonable accuracy in identifying hibernating myocardium. Novel superior hybrid methods may provide diagnostic potential. New evidence supports the role of surgical revascularisation in ischaemic heart failure, but the role of viability tests in planning such procedures remains unclear. Research to date has exclusively involved patients with ambulatory heart failure: Investigating the role of hibernation in ADHF is a key avenue for the future. Whilst our understanding of hibernation pathophysiology has improved dramatically, the clinical utility of identifying and targeting hibernation remains unclear.

Optimal Timing of Percutaneous Coronary Intervention in Patients With Non-ST-Segment Elevation Myocardial Infarction Complicated by Acute Decompensated Heart Failure (from the Korea Acute Myocardial Infarction Registry-National Institutes of Health [KAMIR-NIH])

The optimal timing of percutaneous coronary intervention (PCI) in patients with non-ST-segment elevation myocardial infarction (NSTEMI), complicated by acute decompensated heart failure (ADHF), is unclear. A total of 1,027 patients with NSTEMI complicated by ADHF who underwent successful PCI were analyzed using a Korean multicenter registry. All patients were divided into 4 groups by the timing of PCI: group 1 (PCI < 2 hour after admission, n = 149), group 2 (2 to 24 hours, n = 577), group 3 (24 to 72 hours, n = 189), and group 4 (≥72 hours, n = 112). We analyzed the incidences of 12-month mortality, nonfatal myocardial infarction (MI), target-vessel revascularization, and rehospitalization because of HF. The prevalence of ADHF in patients with NSTEMI was 15.2% at initial presentation, and in-hospital mortality was higher in group 1 than in the other groups. There were no significant differences in mortality, nonfatal MI, target-vessel revascularization, or rehospitalization for HF during the 12-month follow-up between groups, regardless of initial PCI timing, except for a higher 12-month mortality in patients who received PCI within 24 hours (vs ≥24 hours) (hazard ratio 1.52, 95% confidence interval 1.09 to 2.29, p = 0.046). Early PCI did not reduce adverse clinical outcomes in patients with NSTEMI complicated by ADHF. Delayed PCI after stabilization may be reasonable in such high-risk patients.

Acute Heart Failure Management

Acute heart failure (AHF) is a life-threatening medical condition, where urgent diagnostic and treatment methods are of key importance. However, there are few evidence-based treatment methods. Interestingly, despite relatively similar ways of management of AHF throughout the globe, mid-term outcome in East Asia, including South Korea is more favorable than in Europe. Yet, most of the treatment methods are symptomatic. The cornerstone of AHF management is identifying precipitating factors and specific phenotype. Multidisciplinary approach is important in AHF, which can be caused or aggravated by both cardiac and non-cardiac causes. The main pathophysiological mechanism in AHF is congestion, both systemic and inside the organs (lung, kidney, or liver). Cardiac output is often preserved in AHF except in a few cases of advanced heart failure. This paper provides guidance on AHF management in a time-based approach. Treatment strategies, criteria for triage, admission to hospital and discharge are described.

Risk Stratification and in Hospital Morality in Patients Presenting with Acute Coronary Syndrome (ACS) in Bahrain

Background:

Risk factors and short-term mortality in patients presented with Acute Coronary Syndrome (ACS) in Bahrain has not been evaluated before.

Aim:

In this prospective observational study, we aim to determine the clinical risk profiles of patients with ACS in Bahrain and describe the incidence, pattern of presentation and predictors of in-hospital clinical outcomes after admission.

Methods:

Patients with ACS were prospectively enrolled over a 12 month period. The rate of incidence of risk factors in patients was compared with 635 non-cardiac patient admissions that matched for age and gender. Multiple logistic regression analysis was used to predict poor outcomes in patients with ACS. The variables were ages >65 years, body mass index (BMI) >28 kg/m², GRACE (Global Registry of Acute Coronary Events) score >170, history of diabetes mellitus (DM), systolic hypertension >180 mmHg, level of creatinine >160 μmol/l and Heart Rate (HR) on admission >90 bpm, serum troponin rise and ST segment elevation on the ECG.

Results:

Patients with ACS (n=635) were enrolled consecutively. Mean age was 61.3 ± 13.2 years, with 417 (65.6%) male. Mean age for patients with ST-segment elevation myocardial infarction (STEMI, n=156) compared with non-STEMI (NSTEMI, n=158) and unstable angina (UA, n=321) was 56.5± 12.8 vs 62.5±14.0 years respectively. In-hospital mortality was 5.1%, 3.1% and 2.5% for patients with STEMI, NSTEMI, and UA, respectively. In STEMI patients, thrombolytic therapy was performed in 88 (56.5%) patients and 68 (43.5%) had primary coronary angioplasty (PCI). The predictive value of different clinical variables for in-hospital mortality and cardiac events in the study were: 2.8 for GRACE score >170, 3.1 for DM, 2.2 for SBP >180 mmHg, 1.4 for age >65 years, 1.8 for BMI >28, 1.7 for creatinine >160 μmol/L, 2.1 for HR >90 bpm, 2.2 for positive serum troponin and 2.3 for ST elevation.

Conclusion:

Patients with STEMI compared with NSTEMI and UA were of younger age. There was higher in-hospital mortality in STEMI compared with NSTEMI and UA patients. The most significant predictors of death or cardiac events on admission in ACS were DM, GRACE Score >170, systolic hypertension >180 mmHg, positive serum troponin and HR >90 bpm.

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.

Coronary angiography in worsening heart failure: determinants, findings and prognostic implications

Objectives

Coronary angiography is regularly performed in patients with worsening signs and/or symptoms of heart failure (HF). However, little is known on the determinants, findings and associated clinical outcomes of coronary angiography performed in patients with worsening HF.

Methods

The BIOSTAT-CHF (a systems BIOlogy Study to TAilored Treatment in Chronic Heart Failure) programme enrolled 2516 patients with worsening symptoms and/or signs of HF, either hospitalised or in the outpatient setting. All patients were included in the present analysis.

Results

Of the 2516 patients included, 315 (12.5%) underwent coronary angiography within the 30 days after the onset of worsening symptoms and/or signs of HF. Subjects who underwent angiography were more often observed as inpatients, had more often an overt acute coronary syndrome, had higher troponin I levels, were younger and had better renal function (all p≤0.01). Patients who underwent coronary angiography had a lower risk of the primary outcome of death and/or HF hospitalisation (adjusted HR=0.71, 95% CI 0.57 to 0.89, p=0.003) and death (adjusted HR=0.59, 95% CI 0.43 to 0.80, p=0.001). Among the patients who underwent coronary angiography, those with a coronary stenosis (39%) had a worse prognosis than those without stenosis (adjusted HR for the primary outcome=1.71, 95% CI 1.10 to 2.64, p=0.016).

Conclusions

Coronary angiography was performed in <13% of patients with symptoms and/or signs of worsening HF. These patients were remarkably different from those who did not undergo coronary angiography and had a lower risk of subsequent events. The presence of coronary stenosis on coronary angiography was associated with a worse prognosis.

Etiology of Heart Failure and Outcomes in Patients Hospitalized for Acute Decompensated Heart Failure With Preserved or Reduced Ejection Fraction

In the setting of acute decompensated heart failure (HF), relations among the etiology of HF, left ventricular systolic function, and outcomes are unclear. The aim of this study was to investigate the association of HF etiology with outcomes in patients with acute decompensated HF with a preserved or reduced ejection fraction (EF). Of the 4,842 patients enrolled in the Acute Decompensated Heart Failure Syndromes registry, 3,810 patients (1,601 with a preserved EF and 2,209 with a reduced EF) who had a hypertensive, ischemic, valvular, or idiopathic dilated etiology of HF were investigated to assess the association of etiology with a composite end point (all-cause mortality and readmission for HF). The median follow-up period after admission was 502 (381 to 759) days. The composite end point was reached in 44.6% and 41.7% of the preserved and reduced EF groups, respectively. After adjustment for multiple co-morbidities, the risk of the composite end point was comparable among hypertensive, ischemic, and valvular etiologies in the preserved EF group. In contrast, in the reduced EF group, ischemic etiology was associated with a tendency toward greater risk of the composite end point than hypertensive etiology (but this difference was not significant), whereas valvular etiology was associated with a significantly greater risk of the composite end point relative to hypertensive or idiopathic dilated etiology. In conclusion, this study demonstrated that taking the etiology of HF into account may help to reduce the heterogeneity of acute decompensated HF and assist in identifying patients at risk of adverse outcomes, especially among patients with reduced EF.

Pharmacological reasons that may explain why randomized clinical trials have failed in acute heart failure syndromes

Acute heart failure (AHF) represents a clinical challenge as it encloses a heterogeneous group of syndromes (AHFS) with different pathophysiology, clinical presentations, prognosis and response to therapy. In the last 25years multiple therapeutic targets have been identified and numerous new drugs were evaluated but, up to now, all failed to demonstrate a consistent benefit on clinical outcomes. Moreover, a repeated finding has been the poor correlation between the encouraging results of preclinical and early clinical trials and the lack of effect on outcomes observed in phase III trials. We review several possible pharmacological reasons that may explain the lack of success to develop new drugs and the pharmacological challenges to overcome in the future to develop new more effective and safer drugs for the treatment of AHFS.

Prognostic impact of comorbidities in hospitalized patients with acute exacerbation of chronic heart failure

BACKGROUND

To assess the impact of comorbidities on long-term all-cause mortality in patients hospitalized with exacerbated signs/symptoms of previously chronic stable HF (AE-CHF).

METHODS

1119 patients admitted for AE-CHF and with NT-proBNP levels >900pg/mL were enrolled. Univariable and multivariable Cox analyses were performed to assess the association of age, gender, hypertension, diabetes, obesity, atrial fibrillation, coronary heart disease (CHD), chronic obstructive pulmonary disease, previous cerebrovascular accidents, chronic liver disease (CLD), thyroid disease, renal impairment (RI), and anemia with 3-year all-cause mortality.

RESULTS

During the follow-up, 441 patients died and 126 underwent heart transplantation (HT) or ventricular assist device (VAD) implantation. 45.8% of the fatal events and 52.4% of HT/VAD implantations occurred within 180days after admission. Increasing age (p=.012), obesity (p=.037), atrial fibrillation (p=.030), CHD (p=.015), CLD (p=.001), RI (p<.001), and anemia (p<.001) were independently associated with 3-year all-cause mortality. Most of the prognostic impact of CHD, took place within the first 180days after admission. Male gender was associated with mortality beyond 180days. Compared with normal weight, obesity was associated with better overall survival. Obese patients, however, had significantly lower NT-proBNP concentrations and less frequently presented with hypotension, hyponatremia, and severe left ventricular systolic dysfunction, despite a similar prevalence of severe dyspnea at admission.

CONCLUSIONS

Several comorbidities are associated with long-term risk of death in hospitalized patients with worsening HF, although the nature of this association does appear to be complex. Our data may help to raise awareness about the clinical relevance of comorbid conditions.

Single baseline serum creatinine measurements predict mortality in critically ill patients hospitalized for acute heart failure

Background

Acute heart failure (AHF) is a leading cause of death in critically ill patients and is often accompanied by significant renal dysfunction. Few data exist on the predictive value of measures of renal dysfunction in large cohorts of patients hospitalized for AHF.

Methods

Six hundred and eighteen patients hospitalized for AHF (300 male, aged 73.3 ± 10.3 years, 73% New York Heart Association Class 4, mean hospital length of stay 12.9 ± 7.7 days, 97% non‐ischaemic AHF) were included in a retrospective single‐centre data analysis. Echocardiographic data, serum creatinine/urea levels, estimated glomerular filtration rate (eGFR), and clinical/laboratory markers were recorded. Mean follow‐up time was 2.9 ± 2.1 years. All‐cause mortality was recorded, and univariate/multivariate analyses were performed.

Results

Normal renal function defined as eGFR > 90 mL/min/1.73 m² was noted in only 3% of AHF patients at baseline. A significant correlation of left ventricular ejection fraction with serum creatinine levels and eGFR (all P < 0.002) was noted. All‐cause mortality rates were 12% (90 days) and 40% (at 2 years), respectively. In a multivariate model, increased age, higher New York Heart Association class at admission, higher total cholesterol levels, and lower eGFR independently predicted death. Patients with baseline eGFR < 30 mL/min/1.73 m² had an exceptionally high risk of death (odds ratio 2.80, 95% confidence interval 1.52–5.15, P = 0.001).

Conclusions

In a large cohort of patients with mostly non‐ischaemic AHF, enhanced serum creatinine levels and reduced eGFR independently predict death. It appears that patients with eGFR < 30 mL/min/1.73 m² have poorest survival rates. Our data add to mounting data indicating that impaired renal function is an important risk factor for non‐survival in patients hospitalized for AHF.

Imaging Techniques in Acute Heart Failure

In recent years, imaging techniques have revolutionized the diagnosis of heart failure. In patients with a clinical picture of acute decompensation, prognosis is largely determined by early implementation of general measures and treatment of the underlying cause. Given its diagnostic yield and portability, ultrasound has become an essential tool in the setting of acute heart failure, and is currently found in all medical departments involved in the care of the critically ill patient. Cardiac magnetic resonance and computed tomography allow detailed characterization of multiple aspects of cardiac structure and function that were previously unavailable. This helps guide and monitor many of the treatment decisions in the acute heart failure population in an entirely noninvasive way. This article aims to review the usefulness of the imaging techniques that are clinically relevant in the context of an episode of acute heart failure. We discuss the indications and limitations of these techniques in detail and describe the general principles for the appropriate interpretation of results.

Falla cardíaca aguda

Se presenta el caso clínico de una mujer de 26 años de edad, que acudió al Hospital Universitario San Vicente Fundación (Medellín) con síntomas y signos de falla cardíaca aguda y diagnóstico previo de falla cardíaca crónica con fracción de expulsión disminuida, de origen no claro, tromboembolismo pulmonar y ataque cerebrovascular isquémico, sin modulación neurohormonal óptima. Ingresó a la institución con hallazgos clínicos de sobrecarga hídrica y baja perfusión tisular, con requerimiento de soporte inotrópico y diuréticos parenterales; se logró estabilizarla e introducir progresivamente la terapia médica para la falla cardíaca. Para el estudio del origen de esta enfermedad, se hizo resonancia magnética de corazón, que demostró un área de realce tardío en el territorio de la arteria descendente anterior, sugestiva de necrosis, por lo que se le efectuó coronariografía, en la que no se hallaron lesiones en las arterias coronarias epicárdicas. Finalmente se logró la compensación de la falla cardíaca aguda y se decidió hacer anticoagulación crónica por la probable trombofilia de la paciente, en concordancia con los fenómenos trombóticos arteriales y venosos recurrentes.

Roadmap to inpatient heart failure management

Heart failure (HF) accounts for over 1 million primary hospitalizations in the USA each year and carries a tremendous burden on costs and patient outcomes. The clinical syndrome of HF is not a single disease, but represents the complex interplay between various cardiac and non-cardiac processes, each of which need to be individually addressed. This review provides an updated, contemporary roadmap for inpatient worsening chronic HF management with a focus on identifying and addressing initiating mechanisms, amplifying factors, and cardiac structural abnormalities. Inpatient risk stratification should guide patient education, team structuring, disposition, and post-discharge monitoring.

Prevalence and 1-year prognosis of transient heart failure following coronary revascularization

The occurrence of heart failure during the whole pre-discharge course of coronary revascularization, as far as its influence on subsequent prognosis, is poorly understood. The present study examined the effect of transient heart failure (THF) developing in the acute and rehabilitative phase on survival after coronary artery bypass graft surgery (CABG) and percutaneous coronary intervention (PCI). Patients in the Italian survey on cardiac rehabilitation and secondary prevention after cardiac revascularization (ICAROS) were analyzed for THF, the latter being defined either as signs and symptoms consistent with decompensation or cardiogenic shock. ICAROS was a prospective, multicenter registry of 1,262 consecutive patients discharged from 62 cardiac rehabilitation (CR) facilities, providing data on risk factors, lifestyle habits, drug treatments, and major cardiovascular events (MACE) during a 1-year follow-up. Records were linked to the official website of the Italian Association of Cardiovascular Prevention and Rehabilitation (GICR-IACPR). The overall prevalence of pre-discharge THF was 7.6%, with 69.8% of cases in acute wards, 22.9% during CR, and 7.3% in both settings. THF affected more frequently patients with chronic cardiac condition (42.7 vs. 30.6%; p < 0.05), age ≥75 years (33.3 vs. 23.1%; p < 0.005), COPD (19.8 vs. 12.3%; p < 0.05), and chronic kidney disease (17.7 vs. 7%; p < 0.001). After discharge, THF patients showed good maintenance rates of RAAS modulators (90.6%) and beta-blockers (83.3%), while statin therapy significantly decreased from 81.3 to 64.6% (p < 0.05). The pursuit of secondary prevention targets, as far as self-reported drug adherence, was not different among groups. Patients with THF had increased 1-year mortality (8.3 vs. 1.6%, p < 0.001). Moreover, THF independently predicted adverse outcome with OR for recurrent events (mainly further episodes of decompensation) of 2.4 (CI 1.4-4.3). Patients who experienced THF after coronary revascularization had increased post-discharge mortality and cardiovascular events. Hemodynamic instability, rather than recurrent myocardial ischemia, seems to be linked with worse prognosis.

Coronary artery disease and 10-year outcome after hospital admission for heart failure with preserved and with reduced ejection fraction

AIMS

The prognostic impact of coronary artery disease (CAD) in heart failure is debated. Whereas causes of death have been well described in patients with cardiomyopathy, little is known about how CAD influences causes of death in heart failure with preserved ejection fraction (HFPEF). We undertook a 10-year study and analysed causes of death in relation with CAD in HFPEF and in heart failure with reduced ejection fraction (HFREF).

METHODS AND RESULTS

Our prospective analysis included 591 consecutive patients (320 HFPEF and 271 HFREF) hospitalized for the first time for heart failure during 2000 and followed for 10 years. History of CAD was documented in 25% of HFPEF and 39% of HFREF patients (P < 0.001). Overall, CAD was independently predictive of all-cause and cardiovascular death. CAD had powerful prognostic impact in HFREF [adjusted hazard ratio (HR) 1.60 (1.19-2.15) for all-cause death, and adjusted HR 2.01 (1.38-2.92) for cardiovascular death]. In HFPEF, the association between CAD and cardiovascular death was no longer observed after adjustment [adjusted HR 1.01 (0.69-1.50)]. In HFREF, CAD was associated with increased risk of heart failure-related (adjusted HR 2.03 (1.21-3.43)] and myocardial infarction-related fatal events [adjusted HR 3.84 (1.16-12.7)], while HFPEF patients with CAD appeared at greater risk of sudden death [adjusted HR 2.22 (1.05-4.95)].

CONCLUSION

The prognostic impact of CAD is different in HFPEF compared with HFREF. Patients with HFPEF and CAD are at high risk of cardiovascular death, especially sudden death.

Anticoagulation in heart failure: current status and future direction

Despite therapeutic advances, patients with worsening heart failure (HF) requiring hospitalization have unacceptably high post-discharge mortality and re-admission rates soon after discharge. Evidence suggests a hypercoagulable state is present in patients with HF. Although thromboembolism as a direct consequence of HF is not frequently clinically recognized, it may contribute to mortality and morbidity. Additionally, many patients with HF have concomitant disorders conferring additional thrombotic risk, including atrial fibrillation (AF) and coronary artery disease (CAD). Acute coronary syndrome (ACS), a known consequence of coronary thrombosis, is a common precipitating factor for worsening HF. Coronary thrombosis may also cause sudden death in patients with HF and CAD. Because data are largely derived from observational studies or trials of modest size, guideline recommendations on anticoagulation for HF vary between organizations. The recently presented Warfarin versus Aspirin in Reduced Cardiac Ejection Fraction trial of HF patients in sinus rhythm suggested anticoagulation reduces the risk of stroke, although rates of the combined primary endpoint (death, ischemic stroke, or intracerebral hemorrhage) were similar for acetylsalicylic acid and warfarin. Newer oral anticoagulants dabigatran, apixaban, and rivaroxaban have successfully completed trials for the prevention of stroke in patients with AF and have shown benefits in the subpopulation of patients with concomitant HF. Positive results of the Anti-Xa Therapy to Lower Cardiovascular Events in Addition to Standard Therapy in Subjects with Acute Coronary Syndrome-Thrombolysis in Myocardial Infarction 51 (ATLAS ACS 2-TIMI 51) trial of rivaroxaban in ACS are also encouraging. These data suggest there is a need to assess the potential role for these newer agents in the management of patients hospitalized for HF who continue to have a high post-discharge event rate despite available therapies.

B-type natriuretic peptide predicts an ischemic etiology of acute heart failure in patients with stage 4-5 chronic kidney disease

OBJECTIVES

The non-invasive differentiation of ischemic and non-ischemic acute heart failure (AHF) not resulting from acute myocardial infarction is difficult and has therapeutic and prognostic implications. The aim of this study was to assess whether plasma B-type natriuretic peptide (BNP) can identify ischemic etiology in patients with stage 4-5 chronic kidney disease (CKD) presenting with AHF.

DESIGN AND METHODS

We prospectively analyzed 61 patients. The diagnosis of ischemic AHF was confirmed by coronary angiography or stress myocardial perfusion imaging. Plasma levels of BNP were measured at admission (BNP1) and 48 h after admission (BNP2).

RESULTS

The mean age of the study patients was 67 years. In these patients, 70.5% had diabetes and 47.5% had dialysis-dependent CKD; 28 of these patients (45.9%) had an ischemic etiology with significantly higher concentrations of BNP1 and BNP2 than did patients without ischemia. The area under the receiver operating characteristic curve was 0.755 (P=0.001) for BNP1 and 0.868 (P<0.001) for BNP2 to detect ischemic etiology of AHF. Plasma BNP1 >2907 ng/L (odds ratio [OR], 10.9; 95% confidence interval [CI] 2.5-48.4; P=0.002) and BNP2 >2322 ng/L (OR 93.1, 95% CI 7.0-1238.7; P=0.001) were independently associated with an ischemic etiology of AHF.

CONCLUSIONS

Plasma BNP may represent a clinically useful non-invasive tool for identification of ischemic etiology of AHF in patients with stage 4-5 CKD.