Chloride in Heart Failure Syndrome: Its Pathophysiologic Role and Therapeutic Implication

Predictive value of the prognostic nutritional index combined with serum chloride levels for the prognosis of patients with acute decompensated heart failure

BACKGROUND

The prognostic nutritional index (PNI) and serum chloride level are related to adverse outcomes in patients with heart failure. However, little is known about the relationship between the PNI and serum chloride level in predicting the poor prognosis of patients with acute decompensated heart failure (ADHF).

METHODS AND RESULTS

We reviewed 1221 consecutive patients with ADHF admitted to the First Affiliated Hospital of Kunming Medical University from January 2017 to October 2021. After excluding patients with in hospital death, missing follow-up data, missing chloride data, missing lymphocyte (LYM) count data, or missing serum albumin data, 805 patients were included. PNI was calculated using the formula: serum albumin (ALB) (g/L) + 5 × LYM count (10^9/L). Patients were divided into 4 groups according to the quartiles of the PNI, and the highest PNI quartile (PNI Q4: PNI ≥ 47.3) was set as the reference group. The patients in the lowest PNI quartile (PNI Q1: PNI < 40.8) had the lowest cumulative survival rate, and mortality risk decreased progressively through the quartiles (log-rank χ2 142.283, P < 0.0001). Patients with ADHF were divided into 8 groups by quartiles of PNI and median levels of serum chloride. After adjustment, the hazard ratio (HR) for all-cause mortality in ADHF patients in Group 1 was 8.7 times higher than that in the reference Group 8. Furthermore, the addition of serum chloride level and PNI quartile to the Cox model increased the area under the Receiver operating characteristic (ROC) curve by 0.05, and the area under the ROC curve of the new model was higher than that of the original model with traditional risk factors.

CONCLUSIONS

Both the lowest PNI quartiles and low chloride level indicate a higher risk of all-cause death in patients with ADHF.

The role of urine chloride in acute heart failure

In our retrospective study, we aimed to investigate the relationship between urinary chloride (uCl-) and selected clinical and laboratory biomarkers, renal function, and patient outcomes in the acute heart failure (AHF) population. We divided 248 adult patients (≥ 18 years) with AHF into two groups: low uCl- (< 115 mmol/L) and high uCl-. The mean age of the patient group was 70.2 ± 12.6, and 182 patients were male (73.4%). Clinical endpoints included in-hospital mortality, one-year mortality, and a composite endpoint of one-year mortality and rehospitalization for heart failure. Patients were followed up for at least one year. Relevant clinical and baseline biomarker data were collected, including markers concerning inflammation, liver and kidney function, perfusion and congestion, iron status, cardiac remodeling, gasometry, renin and aldosterone. Low uCl- was associated with worse in-hospital outcomes, including higher in-hospital mortality (7.7% vs. 1.4%, p = 0.014), the need for inotropic support (20.19% vs. 2.08%, p ≤ 0.001), worsening of HF during therapy (17.31% vs. 4.86%, p ≤ 0.001), and the need for treatment in an intensive cardiac care unit (33.65% vs. 15.28%, p ≤ 0.001). Low uCl- was a significant predictor of one-year mortality (40.4% vs. 16.7%, p < 0.05) and the composite outcome (HR 2.42, 95% CI 1.43-4.08, p < 0.001). In the multivariable analysis, uCl- was independently associated with the risk of one-year mortality (HR 0.92, 95% CI 0.87-0.98, p < 0.05) and the composite outcome (HR 0.95, 95% CI 0.92-0.99, p < 0.05). Our findings suggest that low uCl- is a marker of more advanced heart failure, activation of the renin-angiotensin-aldosterone system and is related to worse one-year outcomes.

The association between serum chloride and mortality in ICU patients with heart failure: The impact of bicarbonate

OBJECTIVE

To assess whether serum chloride predicts risk of death in intensive care unit (ICU) patients with heart failure (HF) and the effect of bicarbonate on the efficacy of serum chloride in predicting risk of death in ICU patients.

METHODS

A total of 9364 HF patients hospitalized in the ICU were enrolled. Patients were divided into hypochloremia (< 96 mEq/L), normal chloride (96-108 mEq/L), and hyperchloremia (> 108 mEq/L) groups. Similarly, we divided the serum bicarbonate level into three groups: low bicarbonate (< 22 mEq/L), medium bicarbonate (22-26 mEq/L), and high bicarbonate (> 26 mEq/L). The outcome of this study was in-hospital mortality. Then, we analyzed the association between abnormal serum chloride and mortality according to the category of serum bicarbonate and assessed the interaction effect. Restricted cubic spline (RCS) was used to show possible nonlinear associations.

RESULTS

In the overall study population, hypochloremia was associated with a higher risk of in-hospital mortality than normal chloride (odds ratio [OR] 1.54, 95% confidence interval [CI] 1.26-1.86, P < 0.001), hyperchloremia was not significantly related to in-hospital mortality (OR 1.00, 95% CI 0.85-1.19, P = 0.962). However, a linear association between serum chloride and in-hospital mortality was found in the low and normal bicarbonate groups (all P for nonlinear >0.05).

CONCLUSIONS

Hypochloremia is associated with in-hospital mortality and longer hospital stay in critically ill patients with HF. In addition, risk of death in the low and medium serum bicarbonate groups decreased with increasing serum chloride level.

A Comprehensive Review of Chloride Management in Critically Ill Patients

Chloride, often overshadowed in electrolyte management, emerges as a crucial player in the physiological intricacies of critically ill patients. This comprehensive review explores the multifaceted aspects of chloride, ranging from its significance in cellular homeostasis to the consequences of dysregulation in critically ill patients. The pathophysiology of hyperchloremia and hypochloremia is dissected, highlighting their intricate impact on acid-base balance, renal function, and cardiovascular stability. Clinical assessment strategies, including laboratory measurements and integration with other electrolytes, lay the foundation for targeted interventions. Consequences of dysregulated chloride levels underscore the need for meticulous management, leading to an exploration of emerging therapies and interventions. Fluid resuscitation protocols, the choice between crystalloids and colloids, the role of balanced solutions, and individualized patient approaches comprise the core strategies in chloride management. Practical considerations, such as monitoring and surveillance, overcoming implementation challenges, and embracing a multidisciplinary approach, are pivotal in translating theoretical knowledge into effective clinical practice. As we envision the future, potential impacts on critical care guidelines prompt reflections on integrating novel therapies, individualized approaches, and continuous monitoring practices. In conclusion, this review synthesizes current knowledge, addresses practical considerations, and envisions future directions in chloride management for critically ill patients. By embracing a holistic understanding, clinicians can navigate the complexities of chloride balance, optimize patient outcomes, and contribute to the evolving landscape of critical care medicine.

Production performance, haematological parameters, serum biochemistry, and expression of HSP-70 in broiler chickens fed dietary ascorbic acid during heat stress

An experiment was carried out to assess the efficacy of supplemental ascorbic acid (AA) on broiler chicken production performance, blood haematological profile, biochemical profile, and carcass traits under heat stress conditions. A total of 192-day-old broiler chicks were divided into four groups, each with six replicates of eight each (4 × 6 × 8). Four corn-based dietary treatments were formulated: T1 (control diet), T2 (T1 + AA at 200 mg/kg), T3 (T1 + AA at 400 mg/kg), and T4 (T1 + AA at 600 mg/kg) for a period of 42 days. Despite the high temperature and humidity, the 600 mg AA supplemental groups (T4) gained significantly (P ≤ 0.05) more body weight and had a higher feed intake and better feed conversion ratio (FCR) than the control group (T1). After 28 days of feeding the three AA-supplemented diets, antibody titres (humoral immune response) were significantly higher (P ≤ 0.05). The response to intradermally injected phyto-haemagglutinin (PHA-P), an index of the in vivo cell-mediated immune response, was found to be increased (P ≤ 0.05) in the 400 and 600 mg AA-supplemented groups after 35 days. Higher levels of AA (T4) supplementation significantly (P ≤ 0.05) improved haematological values such as haemoglobin (Hb), total erythrocyte count (TEC), total leukocyte count (TLC), and differential leukocyte count (DLC), heterophil:lymphocyte (H:L) in comparison to the control group (T1). The supplemented group improved the serum biochemical profile of the birds, with an increase (P ≤ 0.05) in total serum protein, albumin, and globulin and a decrease in serum cholesterol and corticosterone levels in the T4 group compared to the control group. Heat shock protein-70 (HSP-70) was gradually elevated after increasing the ascorbic acid concentration (P ≤ 0.05) at 14 and 21 days. As a result, it can be concluded that supplementing ascorbic acid at 600 mg/kg is beneficial for improving the performance, immunity, and blood haematological biochemical profile and upregulating the HSP-70 gene of broiler chickens under heat stress conditions.

U-Shaped Association between Serum Chloride Levels and In-Hospital Mortality in Patients with Congestive Heart Failure in Intensive Care Units

Serum chloride level has clinical significance in the prognosis of heart failure. Little is known regarding the association between serum chloride levels and in-hospital mortality in patients with heart failure.This retrospective study used clinical data obtained from the Medical Information Mart for Intensive Care Database. The study cohort comprised patients who were categorized on the basis of their serum chloride levels, and the primary endpoint was in-hospital mortality. To assess the impact of serum chloride levels at the time of intensive care unit admission on in-hospital mortality, we used various statistical approaches, including multivariable logistic regression models, a generalized additive model, and a two-piecewise linear regression model. In addition, subgroup analysis was conducted to examine the robustness of the main findings.This study comprised 15,983 participants. When compared with the reference group (Q5), the groups with the highest (Q7) and lowest (Q1) blood chloride levels exhibited increased in-hospital mortality, with fully adjusted odds ratios (ORs) of 1.36 [95% confidence interval (CI): 1.08-1.71] and 1.25 (95% CI: 1-1.56), respectively. A U-shaped relationship was observed between blood chloride levels and in-hospital mortality, with the lowest risk observed at a threshold of 105.017 mmol/L. The effect sizes and corresponding CIs below and above the threshold were 0.969 (95% CI: 0.957-0.982) and 1.039 (95% CI: 1.002-1.076), respectively. Stratified analyses demonstrated the robustness of this correlation.The relationship between serum chloride levels and in-hospital mortality in patients with heart failure was U-shaped, with an inflection point of 105.017 mmol/L.

Machine learning algorithms to predict major adverse cardiovascular events in patients with diabetes

BACKGROUND

Major Adverse Cardiovascular Events (MACE) are common complications of type 2 diabetes mellitus (T2DM) that include myocardial infarction (MI), stroke, and heart failure (HF). The objective of the current study was to predict MACE among T2DM patients.

METHODS

Type 2 diabetes mellitus patients above 18 years old were recruited for the study from the All of Us Research Program. Eligible participants were those who took sodium-glucose cotransporter 2 inhibitors. Different Machine learning algorithms: including RandomForest (RF), XGBoost, logistic regression (LR), and weighted ensemble model (WEM) were employed. Clinical attributes, electrolytes and biomarkers were explored in predicting MACE. The feature importance was determined using mean decrease accuracy.

RESULTS

Overall, 9, 059 subjects were included in the analyses, of which 5197 (57.4%) were females. The XGBoost Model demonstrated a prediction accuracy of 0.80 [0.78-0.82], which is higher as compared to the RF 0.78[0.76-0.80], the LR model 0.65 [0.62-0.67], and the WEM 0.75 [0.73-0.76], respectively. The classification accuracy of the models for stroke was more than 95%, which was higher than prediction accuracy for MI (∼85%), and HF (∼80%). Phosphate, blood urea nitrogen and troponin levels were the major predictors of MACE.

CONCLUSION

The ML models had shown acceptable performance in predicting MACE in T2DM patients, except the LR model. Phosphate, blood urea nitrogen, and other electrolytes were important predictors of MACE, which is consistent between the individual components of MACE, such as stroke, MI, and HF. These parameters can be calibrated as prognostic parameters of MACE events in T2DM patients.

Electrochemical Sensing of Urinary Chloride Ion Concentration for Near Real-Time Monitoring

Urinary chloride concentration is a valuable health metric that can aid in the early detection of serious conditions, such as acid base disorders, acute heart failure, and incidences of acute renal failure in the intensive care unit. Physiologically, urinary chloride levels frequently change and are difficult to measure, involving time-consuming and inconvenient lab testing. Thus, near real-time simple sensors are needed to quickly provide actionable data to inform diagnostic and treatment decisions that affect health outcomes. Here, we introduce a chronopotentiometric sensor that utilizes commercially available screen-printed electrodes to accurately quantify clinically relevant chloride concentrations (5-250 mM) in seconds, with no added reagents or electrode surface modification. Initially, the sensor's performance was optimized through the proper selection of current density at a specific chloride concentration, using electrical response data in conjunction with scanning electron microscopy. We developed a unique swept current density algorithm to resolve the entire clinically relevant chloride concentration range, and the chloride sensors can be reliably reused for chloride concentrations less than 50 mM. Lastly, we explored the impact of pH, temperature, conductivity, and additional ions (i.e., artificial urine) on the sensor signal, in order to determine sensor feasibility in complex biological samples. This study provides a path for further development of a portable, near real-time sensor for the quantification of urinary chloride.

Prognostic Significance of Serum Chloride Level Reduction in Patients with Chronic Heart Failure with Different Ejection Fractions

Little is known regarding the prognostic value of serum chloride in patients with chronic heart failure (CHF) with different ejection fractions. We sought to determine the postdischarge outcomes associated with lower serum chloride between different CHF types.We reviewed the medical records of 1221 consecutive patients with CHF admitted to the First Affiliated Hospital of Kunming Medical University from January 2017 to October 2021. After excluding patients with in-hospital death, missing follow-up data, missing serum chloride level data, or chronic dialysis therapy, 791 patients were included. Of these patients, 343 had heart failure with reduced ejection fraction (HFrEF; i.e., left ventricular ejection fraction (LVEF) < 40%), and 448 had heart failure with preserved ejection fraction (HFpEF) or heart failure with median ejection fraction (HFmrEF; HFpEF plus HFmrEF; i.e., LVEF ≥40%). Over a median follow-up of 750 days, 344 patients (43.5%) had all-cause mortality. In the univariate analysis, serum sodium and chloride were strongly associated with mortality in both HF subgroups (P < 0.0001). A multivariable model including both serum sodium and chloride showed the highly significant association between serum chloride and survival (P < 0.0001), whereas the association between serum sodium and mortality was not reported (HFpEF plus HFmrEF, hazard ratio (HR) 0.975, 95% confidence interval [CI] 0.942-1.010, P = 0.158; HFrEF, HR 1.007, 95% CI 0.966-1.051, P = 0.734). Kaplan-Meier survival curve analysis revealed a significant difference in mortality risk with decreasing chloride levels in all patients with CHF. The optimal cutoff value of chloride in predicting all-cause mortality was 102.95 mmol/L with area under the curve value of 0.76 [HR 0.760, 95% CI 0.727-0.793, P < 0.0001], sensitivity of 60.2%, and specificity of 78.3%.Lower serum chloride is an independent predictor of death in CHF, regardless of heart failure subtype.

Toward quantification of loop diuretic responsiveness for congestive heart failure

Diuretics, such as furosemide, are routinely administered to dogs with congestive heart failure (CHF). Traditionally, dose and determination of efficacy primarily are based on clinical signs rather than quantitative measures of drug action. Treatment of human CHF patients increasingly is guided by quantification of urine sodium concentration (uNa) and urine volume after diuretic administration. Use of these and other measures of diuretic responsiveness is associated with decreased duration of hospitalization, complication rates, future rehospitalization, and mortality. At their core, loop diuretics act through natriuresis, and attention to body sodium (Na) stores and handling offers insight into the pathophysiology of CHF and pharmacology of diuretics beyond what is achievable from clinical signs alone. Human patients with low diuretic responsiveness or diuretic resistance are at risk for difficult or incomplete decongestion that requires diuretic intensification or other remedial strategies. Identification of the specific etiology of resistance in a patient can help tailor personalized interventions. In this review, we advance the concept of loop diuretic responsiveness by highlighting Na and natriuresis. Specifically, we review body water homeostasis and congestion in light of the increasingly recognized role of interstitial Na, propose definitions for diuretic responsiveness and resistance in veterinary subjects, review relevant findings of recent studies, explain how the particular cause of resistance can guide treatment, and identify current knowledge gaps. We believe that a quantitative approach to loop diuretic usage primarily involving natriuresis will advance our understanding and care of dogs with CHF.

Key nutrients important in the management of canine myxomatous mitral valve disease and heart failure

The most common cause of heart failure in dogs is myxomatous mitral valve disease (MMVD), which accounts for approximately 75% of canine heart disease cases and is especially common in smaller dogs. Although low-sodium diets have been recommended for humans with heart diseases for decades, there is little evidence to support this practice in dogs. In recent years, however, it has become clear that other nutrients are important to heart health. Dogs with heart disease secondary to MMVD experience patterns of metabolic changes that include decreased mitochondrial energy metabolism and ATP availability, with increased oxidative stress and inflammation. These changes occur early in disease and progress with worsening heart disease. Key nutrients that may support normal function and address these changes include omega-3 fatty acids, medium-chain triglycerides, magnesium, antioxidants including vitamin E and taurine, and the amino acids methionine and lysine. The long-chain omega-3 fatty acids provide anti-inflammatory, antithrombotic, and other benefits. Medium-chain fatty acids and ketones derived from medium-chain triglycerides provide an alternative energy source for cardiac mitochondria and help reduce free radical production. Magnesium supports mitochondrial function, normal cardiac rhythm, and provides other benefits. Both vitamin E and taurine counter oxidative stress, and taurine also has direct cardiac benefits. Dogs with MMVD have reduced plasma methionine. Methionine and lysine are important for carnitine production as well as other functions. This article reviews the evidence supporting the functions and benefits of these and other nutrients in MMVD and other cardiac conditions.

Serum Chloride Is Inversely Associated With 3 Months Outcomes in Chinese Patients With Heart Failure, a Retrospective Cohort Study

Background

Serum chloride was recently found to be associated with prognosis of heart failure in western countries. However, the evidence was scarce in Asia. We aimed to investigated the relationship between serum chloride and clinical outcomes in a Chinese cohort with hospitalized heart failure.

Methods

We retrospectively analyzed the data from PhysioNet, involving 1996 patients who were admitted with heart failure between December 2016 and June 2019. Outcome was a composite endpoint of all-cause death or rehospitalization at 3 months.

Results

The incidence of the composite endpoint was 26.8% (535/1,996); it was 32.2% (213/662), 25.0% (165/661), and 23.3% (157/673) by chloride tertiles (from the lowest to the highest), respectively. The serum chloride at admission was independently and inversely associated with the composite endpoint risk (hazard ratio: 0.967; 95% confidence interval: 0.939 to 0.996; p = 0.026) in contrast to sodium, which was no longer significant (p > 0.05) after multivariable adjustment. Pearson correlation between serum chloride and sodium was 0.747 (p < 0.001). However, an increased AUC was not observed by adding sodium to model composed of age, sex, NYHA class, diabetes, log BNP and chloride (0.620 vs. 0.612, p = 0.132). Subgroup analysis showed the presence or absence of hyponatremia did not affect the association between chloride and composite endpoint risk.

Conclusions

Low serum chloride at admission was associated with poor outcomes in Chinese hospitalized patients with heart failure. These findings warrant future studies for tackling the potential pathophysiological mechanisms and correction methods of hypochloremia in heart failure.

Mechanistic insights into chloride-related heart failure progression according to the plasma volume status

Aims

Two types of heart failure (HF) progression were recently proposed on the basis of an increased vs. non‐increased serum chloride concentration. The applicability of this concept to real‐world HF pathophysiology requires further investigation. The present study evaluated the mechanisms of HF progression to a different type according to changes in the estimated plasma volume status (ePVS).

Methods and results

Data from 47 patients (32% men; 78.2 ± 9.7 years of age) with stable to worsening HF (37.5 ± 16 days) were analysed. Physical examination, standard blood tests, and b‐type natriuretic peptide (BNP) measurements were conducted. The ePVS was calculated as follows: ePVS (dL/g) = [100 − haematocrit (%)]/[haemoglobin (g/dL)]. For the study subjects as a whole (n = 47), changes in the ePVS correlated positively with changes in the serum chloride concentration from stable to worsening HF (r = 0.398, P = 0.0056). When divided into two groups of worsening HF with an increased (n = 31) vs. non‐increased serum chloride concentration (n = 16), no significant baseline differences in body weight, serum logBNP, or ePVS were detected between groups. Under worsening HF, the increase in body weight (2.34 ± 1.12 vs. 2.59 ± 1.56 kg, P = 0.57) and logBNP (0.39 ± 0.30 vs. 0.54 ± 0.31 pg/mL, P = 0.13) did not differ between groups, but the increase in the ePVS was smaller in the group with a non‐increased serum chloride concentration compared with that with an increased serum chloride concentration (0.292 ± 0.49 vs. 0.653 ± 0.60 dL/g, P = 0.044). An increase in the %change in ePVS ≥ 10% was less common in patients with a non‐increased chloride concentration (37% vs. 71%, P = 0.03). Patients with a non‐increased serum chloride concentration had more HF signs (3.31 ± 0.79 vs. 2.65 ± 0.71, P = 0.005) and a higher incidence of pulmonary rales (63% vs. 16%, P = 0.0024) than those with an increased serum chloride concentration.

Conclusions

According to the changes in the ePVS, HF progression may result from a difference between two HF types (i.e. increased vs. non‐increased serum chloride concentration) in the cardiac reserve in response to a given cardiac burden by modulating plasma volume status via the possible tonicity potential of chloride.