Hyponatremia and congestive heart failure: a marker of increased mortality and a target for therapy

Risk factors for cardio-cerebrovascular events among patients undergoing continuous ambulatory peritoneal dialysis and their association with serum magnesium

Serum magnesium levels exceeding 0.9 mmol/L are associated with increased survival rates in patients with CKD. This retrospective study aimed to identify risk factors for cardio-cerebrovascular events among patients receiving continuous ambulatory peritoneal dialysis (CAPD) and to examine their correlations with serum magnesium levels. Sociodemographic data, clinical physiological and biochemical indexes, and cardio-cerebrovascular event data were collected from 189 patients undergoing CAPD. Risk factors associated with cardio-cerebrovascular events were identified by univariate binary logistic regression analysis. Correlations between the risk factors and serum magnesium levels were determined by correlation analysis. Univariate regression analysis identified age, C-reactive protein (CRP), red cell volume distribution width standard deviation, red cell volume distribution width corpuscular volume, serum albumin, serum potassium, serum sodium, serum chlorine, serum magnesium, and serum uric acid as risk factors for cardio-cerebrovascular events. Among them, serum magnesium ≤0.8 mmol/L had the highest odds ratio (3.996). Multivariate regression analysis revealed that serum magnesium was an independent risk factor, while serum UA (<440 μmol/L) was an independent protective factor for cardio-cerebrovascular events. The incidence of cardio-cerebrovascular events differed significantly among patients with different grades of serum magnesium (χ2 = 12.023, p = 0.002), with the highest incidence observed in patients with a serum magnesium concentration <0.8 mmol/L. High serum magnesium levels were correlated with high levels of serum albumin (r = 0.399, p < 0.001), serum potassium (r = 0.423, p < 0.001), and serum uric acid (r = 0.411, p < 0.001), and low levels of CRP (r = -0.279, p < 0.001). In conclusion, low serum magnesium may predict cardio-cerebrovascular events in patients receiving CAPD.

Admission hyponatraemia as heart failure events predictor in patients with acute heart failure

AIMS

Heart failure remained consistent as one of the biggest cardiovascular problems in Indonesia. Hyponatraemia is a common electrolyte disorder among patients presented with heart failure; however, the prognostic value for worsening heart failure has not been well defined.

METHODS AND RESULTS

We studied 134 patients admitted with acute heart failure and investigated the relationship between admission serum sodium and the composite clinical outcomes of all-cause mortality and hospitalization ambispectively with a follow-up duration of 6 months. We also try to look for low sodium-level impacts in several conditions. Among 134 patients, 84 patients presented with low sodium during admission, defined as a serum sodium level of <135 mEq/L, and it was associated with higher composite clinical outcome risk [odds ratio (OR), 5.9; 95% confidence interval (CI), 2.8-12.0; P < 0.001]. Moreover, hyponatraemia impacts on composite endpoints were driven by both parameters; it was independently associated with mortality (OR, 3.1; 95% CI, 1.4-6.8; P = 0.003) and rehospitalization (OR, 5.3; 95% CI, 2.4-11.7; P < 0.001). This result remained consistent in most subgroups.

CONCLUSIONS

On-admission hyponatraemia is a predictor for 6 month mortality and rehospitalization. Further work is needed to determine if correction of hyponatraemia translates into clinical benefit.

Sodium and potassium changes during decongestion with acetazolamide - A pre-specified analysis from the ADVOR trial

AIMS

Acetazolamide, an inhibitor of proximal tubular sodium reabsorption, leads to more effective decongestion in acute heart failure (AHF). It is unknown whether acetazolamide alters serum sodium and potassium levels on top of loop diuretics and if baseline values modify the treatment effect of acetazolamide.

METHODS AND RESULTS

This is a pre-specified sub-analysis of the ADVOR trial that randomized 519 patients with AHF and volume overload in a 1:1 ratio to intravenous acetazolamide or matching placebo on top of standardized intravenous loop diuretics. Mean potassium and sodium levels at randomization were 4.2 ± 0.6 and 139 ± 4 mmol/L in the acetazolamide arm versus 4.2 ± 0.6 and 140 ± 4 mmol/L in the placebo arm. Hypokalaemia (<3.5 mmol/L) on admission was present in 44 (9%) patients and hyponatraemia (≤135 mmol/L) in 82 (16%) patients. After 3 days of treatment, 44 (17%) patients in the acetazolamide arm and 35 (14%) patients in the placebo arm developed hyponatraemia (p = 0.255). Patients randomized to acetazolamide demonstrated a slight decrease in mean potassium levels during decongestion, which was non-significant over time (p = 0.053) and had no significant impact on hypokalaemia incidence (p = 0.061). Severe hypokalaemia (<3.0 mmol/L) occurred in only 7 (1%) patients, similarly distributed between the two treatment arms (p = 0.676). Randomization towards acetazolamide improved decongestive response irrespective of baseline serum sodium and potassium levels.

CONCLUSIONS

Acetazolamide on top of standardized loop diuretic therapy does not lead to clinically important hypokalaemia or hyponatraemia and improves decongestion over the entire range of baseline serum potassium and sodium levels.

Hyponatremia and Renal Venous Congestion in Heart Failure Patients

OBJECTIVE

The interrelationship between the heart and kidneys has a great importance in the homeostasis of the cardiovascular system. Heart failure patients present intrarenal arterial hypoperfusion and intrarenal venous congestion due to reduced left ventricle ejection fraction, which triggers numerous neurohormonal factors. The aim of this study was to investigate intrarenal vascularization (arterial and venous), as well as the links between it and systemic congestion and, on the other side, with the mortality in patients with heart failure. Material and Methods. This cross-sectional study was performed on a group of 44 patients with heart failure in different stages of evolution and 44 healthy subjects, matched for age and gender, as controls. Serum natremia, NT-proBNP, and creatinine analyses were performed in all patients and controls. Renal and cardiac ultrasonography was done in all patients and controls, recording intrarenal arterial resistive index (RRI), intrarenal venous flow (IRVF) pattern, renal venous stasis index (RVSI), and left ventricular ejection fraction (LVEF). Data are recorded and presented as mean ± standard deviation. Statistical analyses were performed using the Student t-test, ANOVA test, and the Pearson correlation. Differences were considered statistically significant at the value of p < 0.05.

RESULTS

Hyponatremia was identified in 47.72% of the HF patients. This study revealed correlations between serum natremia and LVEF, NT-proBNP, serum creatinine, interlobar venous RVSI (p < 0.00001), and interlobar artery RRI (p ≤ 0.002). Hyponatremia and renal venous congestion represent negative prognostic factors in HF patients.

CONCLUSION

In HF patients, hyponatremia was correlated with cardiac dysfunction and intrarenal venous congestion. Hyponatremia and renal venous congestion represented negative prognostic factors in HF patients.

Prognostic impact of hyponatraemia and hypernatraemia at admission and discharge in heart failure patients with preserved, mid-range and reduced ejection fraction

BACKGROUND

Hyponatraemia is common in patients with acute heart failure (HF).

AIMS

To determine the impact of sodium disturbances on mortality and readmissions in HF with reduced left ventricular ejection fraction (HFrEF), preserved ejection fraction (HFpEF) and mid-range ejection fraction (HFmrEF).

METHODS

This study was a prospective multicentre consecutive registry in 20 hospitals, including patients admitted due to acute HF in cardiology departments. Sodium <135 mmol/L was considered hyponatraemia, >145 mmol/L hypernatraemia and 135-145 mmol/L normal.

RESULTS

A total of 1309 patients was included. Mean age was 72.0 ± 11.9 years, and 810 (61.9%) were male. Mean serum sodium level was 138.6 ± 4.7 mmol/L at hospital admission and 138.1 ± 4.1 mmol/L at discharge. The evolution of sodium levels was: normal-at-admission/normal-at-discharge 941 (71.9%), abnormal-at-admission/normal-at-discharge 127 (9.7%), normal-at-admission/abnormal-at-discharge 155 (11.8%) and abnormal-at-admission/abnormal-at-discharge 86 (6.6%). Hyponatraemia at discharge was more common in HFrEF (109 (20.7%)) than in HFpEF (79 (13.9%)) and HFmrEF (27 (12%)), P = 0.003. The prevalence of hypernatraemia at discharge was similar in the three groups: HFrEF (10 (1.9%)), HFpEF (12 (2.1%)) and HFmrEF (4 (1.9%)), P = 0.96. In multivariate analysis, abnormal sodium concentrations at hospital admission (hazard ratio (HR) 1.42, 95% confidence interval (CI) 1.15-1.76, P = 0.001) and discharge (HR 1.33, 95% CI 1.08-1.64, P = 0.007) were both independently associated with increased mortality and readmissions at 12 months.

CONCLUSIONS

Hyponatraemia and hypernatraemia at admission and discharge predict a poor outcome in patients with acute HF regardless of left ventricular ejection fraction. Hyponatraemia at discharge is more frequent in HFrEF than in the other groups.

A Systematic Review and Meta-Analysis: Hyponatremia Predicted All-Cause and Cardiovascular Mortality in Dialysis Population

BACKGROUND

Hyponatremia is one of the most common disorders of electrolytes. Some research studies reported that hyponatremia was closely associated with mortality in patients with dialysis. However, this viewpoint remains controversial.

OBJECTIVE

We aimed to do a systematic review and meta-analysis to assess the influence of hyponatremia on mortality in patients with dialysis.

METHODS

We identified the eligible studies that investigated the association between hyponatremia and mortality risk in patients under dialysis by searching systematically a series of databases including PubMed, Embase, Cochrane, Web of science, and Ovid from January 2011 to June 2020. Adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs) were pooled.

RESULTS

From 1,116 records identified, 12 studies including prospective and retrospective cohort studies met our inclusion criteria. We found hyponatremia both at baseline (HR: 1.50 and 95% CI: 1.41-1.59) and in time-varying (HR: 1.63 and 95% CI: 1.44-1.84) were significantly correlated to all-cause mortality after multivariable adjusted. By the subgroup analysis, the same results were presented in hemodialysis (HR: 1.48 and 95% CI: 1.38-1.59) or peritoneal dialysis patients (HR: 1.52 and 95% CI: 1.37-1.70). We also observed that lower serum sodium was independently associated with cardiovascular death.

CONCLUSIONS

Hyponatremia was independently associated with all-cause and cardiovascular mortality, and it might predict adverse outcomes of patients under dialysis.

Hyponatremia in heart failure: not just 135 to 145

One of the most frequent in-hospital electrolyte disturbances is hyponatremia. Hyponatremia in heart failure (HF) is mainly associated with hypervolemia resulting from activation of baroreceptor-mediated hormones, such as arginine vasopressin (AVP), renin-angiotensin-aldosterone system, and catecholamines. Various electrolyte imbalance can occur as heart failure progress. The goal of this review was to outline the current literature on hyponatremia in HF patients.

Targeting the Trafficking of Kidney Water Channels for Therapeutic Benefit

The ability to regulate water movement is vital for the survival of cells and organisms. In addition to passively crossing lipid bilayers by diffusion, water transport is also driven across cell membranes by osmotic gradients through aquaporin water channels. There are 13 aquaporins in human tissues, and of these, aquaporin-2 (AQP2) is the most highly regulated water channel in the kidney: The expression and trafficking of AQP2 respond to body volume status and plasma osmolality via the antidiuretic hormone, vasopressin (VP). Dysfunctional VP signaling in renal epithelial cells contributes to disorders of water balance, and research initially focused on regulating the major cAMP/PKA pathway to normalize urine concentrating ability. With the discovery of novel and more complex signaling networks that regulate AQP2 trafficking, promising therapeutic targets have since been identified. Several strategies based on data from preclinical studies may ultimately translate to the care of patients with defective water homeostasis.

Hyponatremia in Heart Failure: Pathogenesis and Management

Hyponatremia is a very common electrolyte abnormality, associated with poor short- and long-term outcomes in patients with heart failure (HF). Two opposite processes can result in hyponatremia in this setting: Volume overload with dilutional hypervolemic hyponatremia from congestion, and hypovolemic hyponatremia from excessive use of natriuretics. These two conditions require different therapeutic approaches. While sodium in the form of normal saline can be lifesaving in the second case, the same treatment would exacerbate hyponatremia in the first case. Hypervolemic hyponatremia in HF patients is multifactorial and occurs mainly due to the persistent release of arginine vasopressin (AVP) in the setting of ineffective renal perfusion secondary to low cardiac output. Fluid restriction and loop diuretics remain mainstay treatments for hypervolemic/dilutional hyponatremia in patients with HF. In recent years, a few strategies, such as AVP antagonists (Tolvaptan, Conivaptan, and Lixivaptan), and hypertonic saline in addition to loop diuretics, have been proposed as potentially promising treatment options for this condition. This review aimed to summarize the current literature on pathogenesis and management of hyponatremia in patients with HF.

Hyponatraemia in heart failure

Hyponatraemia is common in heart failure (HF). It is estimated that over 20% of patients admitted to hospital with HF have hyponatraemia. It has also been repeatedly shown to be a surrogate marker of increased morbidity and mortality in this specific population. This review focuses on the pathophysiology of hyponatraemia through the activation of neurohormonal cascades in HF, the clinical implications of sustained hyponatraemia and treatment options in the management of this challenging phenomenon.

Peripheral Intravenous Volume Analysis (PIVA) for Quantitating Volume Overload in Patients Hospitalized With Acute Decompensated Heart Failure-A Pilot Study

BACKGROUND

To determine the feasibility of peripheral intravenous volume analysis (PIVA) of venous waveforms for assessing volume overload in patients admitted to the hospital with acute decompensated heart failure (ADHF).

METHODS

Venous waveforms were captured from a peripheral intravenous catheter in subjects admitted for ADHF and healthy age-matched controls. Admission PIVA signal, brain natriuretic peptide, and chest radiographic measurements were related to the net volume removed during diuresis.

RESULTS

ADHF patients had a significantly greater PIVA signal on admission compared with the control group (P = .0013, n = 18). At discharge, ADHF patients had a PIVA signal similar to the control group. PIVA signal, not brain natriuretic peptide or chest radiographic measures, accurately predicted the amount of volume removed during diuresis (R² = 0.781, n = 14). PIVA signal at time of discharge greater than 0.20, demonstrated 83.3% 120-day readmission rate.

CONCLUSIONS

This study demonstrates the feasibility of PIVA for assessment of volume overload in patients admitted to the hospital with ADHF.

Management protocols for chronic heart failure in India

Heart failure is a common clinical syndrome and a global health priority. The burden of heart failure is increasing at an alarming rate worldwide as well as in India. Heart failure not only increases the risk of mortality, morbidity and worsens the patient's quality of life, but also puts a huge burden on the overall healthcare system. The management of heart failure has evolved over the years with the advent of new drugs and devices. This document has been developed with an objective to provide standard management guidance and simple heart failure algorithms to aid Indian clinicians in their daily practice. It would also inform the clinicians on the latest evidence in heart failure and provide guidance to recognize and diagnose chronic heart failure early and optimize management.

Prognostic Significance of Discharge Hyponatremia in Heart Failure Patients With Normal Admission Sodium (from the ESCAPE Trial)

Hyponatremia in acute decompensated heart failure (HF) is indicative of a poor prognosis and predicts morbidity and mortality. We explored the predictive utility of hyponatremia at the time of hospital discharge among HF patients with normal admission sodium (Na). Characteristics and outcomes of HF patients enrolled in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness trial, who had normal Na on admission, were compared between those who were hyponatremic (Na <135 meq/L) or normonatremic on discharge. Three hundred six patients with normal admission Na had either hyponatremia (n = 86) or normal Na (n = 220) on discharge. Compared with patients with normal Na on discharge, hyponatremic patients were younger (p = 0.004), with lower discharge systolic (p <0.001) and diastolic (p = 0.004) blood pressure, higher discharge blood urea nitrogen (p = 0.011) despite similar creatinine (p = 0.566), lower ejection fraction (p = 0.007), and higher left ventricular end-diastolic (p = 0.028) and end-systolic (p = 0.007) dimensions. Despite comparable congestion on hospital admission, patients with discharge hyponatremia had a higher degree of decongestion throughout hospitalization evident in the significantly greater admission to discharge weight loss (p = 0.044) and admission to discharge reduction in inferior vena cava diameter (p = 0.014). Despite longer initial hospitalization (p = 0.004), total duration in hospital at 30 days (p = 0.004) and 6 months (p = 0.045), there were no significant differences between patients with discharge hyponatremia versus normal Na on discharge regarding rehospitalization (p = 0.386), all-cause mortality (p = 0.440), and composite of death, cardiac rehospitalization, and cardiac transplant (p = 0.799), all up to 6-month following randomization. Restricted cubic spline analysis also showed no significant relationships between discharge Na and the aforementioned 3 outcomes. Cox proportional hazards regressions showed that discharge hyponatremia did not significantly predict any of the 3 outcomes after adjustment for imbalances at baseline. Among patients with discharge hyponatremia, a poor outcome was more likely if they were also hyponatremic on admission: the composite end point occurred in 69.2% of those also hyponatremic on admission versus 51.2% of those with normal Na on admission but decreased Na on discharge (p = 0.045). Because the median discharge Na level in the discharge hyponatremia group was 132 meq/L, our findings suggest a benign nature of mild discharge hyponatremia in HF patients with normal admission Na.

Relationship and mechanism of Kv2.1 expression to ADH secretion in rats with heart failure

OBJECTIVE

To explore the mechanisms of Kv2.1 on the secretion of ADH in rats with heart failure.

METHODS

In the animal study, 70 healthy male SD rats were selected. Ligation of coronary heart failure model surgery was performed in 60 rats and sham surgery was performed in the other 10 rats. Q-PCR was used to detect the mRNA expression of Kv2.1 in hypothalamus and heart. The protein expression of Kv2.1 and ADH was detected by western blot. In the cell culture study, hypothalamic neurons were cultured and divided into 7 groups. The mRNA expression of Kv2.1 and ADH was detected by Q-PCR. The protein expression of Kv2.1, CamKII, phosphorylation SynapsinI, dephosphorylation SynapsinI and ADH was detected by western blot.

RESULTS

Compared with the control group of heart failure, LVEDD, LVESD, LVEDV and LVESV were significantly decreased (P < 0.01), and LVEF and LVFS were significantly increased (P < 0.01) in the Kv2.1 agonist group; in the Kv2.1 inhibitor group, LVEDD, LVESD, LVEDV and LVESV were significantly increased (P < 0.01), and LVEF and LVFS were significantly decreased (P < 0.01). In cell culture study, after the different concentrations of Kv2.1 inhibitor gradient down the expression of Kv2.1, intracellular Ca²⁺ concentration gradient increased (P < 0.01), CamKII and phosphorylation of SynapsinI protein expression gradient increased (P < 0.01), dephosphorylation of SynapsinI protein expression gradient decreased (P < 0.01), and the ADH mRNA and protein expression of gradient increased (P < 0.01).

CONCLUSIONS

Kv2.1 agonist can prevent the calcium overload by reducing the intracellular Ca²⁺ concentration, so that the phosphorylation of SynapsinI reduces and exocytosis in hypothalamic neurons is inhibited, which ease the secretion of ADH.

Hyponatremia is Associated with Fluid Imbalance and Adverse Renal Outcome in Chronic Kidney Disease Patients Treated with Diuretics

Chronic kidney disease (CKD) is frequently complicated with hyponatremia, probably because of fluid overload or diuretic usage. Hyponatremia in CKD population is associated with increased mortality, but the effect on renal outcome was unknown. We investigated whether hyponatremia is associated with fluid status and is a prognostic indicator for adverse outcomes in a CKD cohort of 4,766 patients with 1,009 diuretic users. We found that diuretic users had worse clinical outcomes compared with diuretic non-users. Hyponatremia (serum sodium <135 mEq/L) was associated with excessive volume and volume depletion, measured as total body water by bioimpedance analysis, in diuretic users, but not in diuretic non-users. Furthermore, in Cox survival analysis, hyponatremia was associated with an increased risk for renal replacement therapy (hazard ratio, 1.45; 95% CI, 1.13-1.85, P < 0.05) in diuretic users, but not in diuretic non-users (P for interaction <0.05); restricted cubic spline model also showed a similar result. Hyponatremia was not associated with all-cause mortality or cardiovascular event whereas hypernatremia (serum sodium >141 mEq/L) was associated with an increased risk for all-cause mortality. Thus, hyponatremia is an indicator of fluid imbalance and also a prognostic factor for renal replacement therapy in CKD patients treated with diuretics.

Kansas City Cardiomyopathy Questionnaire Utility in Prediction of 30-Day Readmission Rate in Patients with Chronic Heart Failure

Background. Heart failure (HF) is one of the most common diagnoses associated with hospital readmission. We designed this prospective study to evaluate whether Kansas City Cardiomyopathy Questionnaire (KCCQ) score is associated with 30-day readmission in patients hospitalized with decompensated HF. Methods and Results. We enrolled 240 patients who met the study criteria. Forty-eight (20%) patients were readmitted for decompensated HF within thirty days of hospital discharge, and 192 (80%) patients were not readmitted. Compared to readmitted patients, nonreadmitted patients had a higher average KCCQ score (40.8 versus 32.6, P = 0.019) before discharge. Multivariate analyses showed that a high KCCQ score was associated with low HF readmission rate (adjusted OR = 0.566, P = 0.022). The c-statistic for the base model (age + gender) was 0.617. The combination of home medication and lab tests on the base model resulted in an integrated discrimination improvement (IDI) increase of 3.9%. On that basis, the KCQQ further increased IDI of 2.7%. Conclusions. The KCCQ score determined before hospital discharge was significantly associated with 30-day readmission rate in patients with HF, which may provide a clinically useful measure and could significantly improve readmission prediction reliability when combined with other clinical components.

A cross-sectional study of hyponatraemia among elderly patients with heart failure in Uganda

BACKGROUND

Hyponatraemia is a common electrolyte disturbance among older patients. We determined the prevalence of and factors associated with hyponatraemia among older patients with predominantly acute decompensated heart failure attending a tertiary hospital in Kampala, Uganda.

OBJECTIVES

Main study aim: (1) to determine the prevalence of hyponatraemia among patients aged 60 years and above with heart failure attending Mulago National Referral Hospital; (2) to describe the factors associated with hyponatraemia among patients aged 60 years and above with heart failure attending Mulago National Referral Hospital.

SETTING

The study was conducted in one tertiary hospital located in the northeast of Kampala, Uganda.

PARTICIPANTS

400 adults aged 60 years and above were identified for the study. Of these, 188 were excluded as they did not fulfil the inclusion criteria and one declined to participate, leaving a final study group of 211 older adults aged 60 years and above, with a clinical diagnosis of heart failure using Framingham's criteria.

RESULTS

The prevalence of hyponatraemia was 24.2% (51/211). Hyponatraemia was mainly found in patients with mild-to-moderate heart failure, New York Heart Association classes 2 and 3. Of the 51 patients with hyponatraemia, 27 (52.9%) had mild hyponatraemia, while 24 (47.1%) had moderate to severe hyponatraemia of 130-125 mmol/L. History of vomiting (OR=2.94, 95% CI 1.29 to 6.70, p=0.010) and use of loop diuretics (OR=2.71, 95% CI 1.13 to 6.52, p=0.026) were identified as independent factors associated with hyponatraemia among older patients with heart failure.

CONCLUSIONS

Our study revealed a relatively high prevalence of hyponatraemia among older patients with mild to moderate heart failure. Patients presenting with a history of vomiting from any cause or use of loop diuretics were more likely to have hyponatraemia.

Early introduction of tolvaptan after cardiac surgery: a renal sparing strategy in the light of the renal resistive index measured by ultrasound

Background

Renal failure is a serious complication after cardiac surgery, which can be caused by long-term intravenous (IV) loop diuretic use. Tolvaptan is an oral selective vasopressin-2 receptor antagonist used in patients irresponsive to loop diuretics. We investigated their renal perfusion changes using the resistive index (RI) postoperatively.

Methods

Serial renal RI, echocardiography, and laboratory examinations from 14 patients requiring continuous postoperative IV loop diuretics were reviewed. Eight patients received tolvaptan (Group T) and six received oral loop diuretics before the discontinuation of IV loop diuretics (Group L). The 1^st data were obtained between postoperative day 0 and 2, the 2^nd when patients were still under IV loop diuretic treatment, the 3^rd after the initiation of tolvaptan or oral loop diuretic, and the 4^th after the discontinuation of IV diuretics.

Results

The 2^nd RI value was higher in Group T than Group L (0.77 ± 0.09 vs. 0.69 ± 0.01, p = 0.049) but significantly decreased after tolvaptan administration [0.77 ± 0.09 to 0.65 ± 0.05 (2^nd to 3^rd), to 0.62 ± 0.04 (to 4^th), both p = 0.006], while no such changes were seen in Group L. The serum sodium and albumin levels, and echo-derived tricuspid annular plane systolic excursion increased only in Group T (134.1 ± 1.5 to 138.8 ± 3.2 mEq/L, 3.3 ± 0.3 to 3.7 ± 0.5 g/dL, 16.4 ± 3.6 to 19.7 ± 4.2 mm, all p <0.05). The duration of IV loop diuretics tended to be shorter in Group T than Group L (5.6 ± 1.6 vs. 8.7 ± 3.6 days, p = 0.051).

Conclusions

Administration of tolvaptan in patients undergoing cardiac surgery may improve their renal perfusion, as reflected by the renal RI measured using renal Doppler ultrasound.

Hyponatremia during hospitalization and in-hospital mortality in patients hospitalized from heart failure

Background

To date, the majority of studies on hyponatremia focussed on hyponatremia at admission, and came from developed countries. This study aimed to identify the prevalence of hyponatremia during hospitalization in patients hospitalized for HF and its association with in-hospital mortality.

Methods

This was an observational study using retrospective data from patients’ records between 2010–2013. It focused on those patients carrying an ICD-10 code of 150.0(Congestive Heart Failure) as their primary diagnosis.

Hyponatremia during hospitalization was defined as serum sodium level lower than 135 mEq/L obtained from a blood chemistry measurement on the next days after admission. Patients’ characteristics were examined and the association between hyponatremia during hospitalization and in-hospital mortality was analyzed.

Results

Among 464 patients hospitalized for HF, hyponatremia during hospitalization was observed in 22 % of patients with 44 % of this group had normal serum sodium level on admission.

Hyponatremia during hospitalization was associated with lower blood pressure on admission, both systolic and diastolic, peripheral oedema, ascites and fatigue. Patients having history of hospitalization for cardiac diseases and renal failure were higher in patients developing hyponatremia during hospitalization. In this group, amiodarone, heparin, insulin and antibiotics were administered more frequently. Factors potentially increase the risk of hyponatremia during hospitalization include history of fatigue (OR = 3.23, 95 % CI 1.79–5.82), presence of ascites (4.14, 1.84–9.31), and administration of heparin (3.85, 1.78–8.31) and antibiotics (3.08, 1.71–5.53). Length of hospital stay was significantly longer in patients with hyponatremia during hospitalization and in-hospital mortality was also higher compared to non-hyponatremic patients, 7.7 % and 29.1 %, respectively.

Conclusion

This study found that the prevalence of hyponatremia during hospitalization in patients hospitalized for HF was almost the same as hyponatremia on admission and administration of heparin and antibiotics can potentially worsen hyponatremia during hospitalization. In this study population, hyponatremia during hospitalization was found to be associated with in-hospital mortality.

Predicting outcomes among patients with atrial fibrillation and heart failure receiving anticoagulation with warfarin

Among patients receiving oral anticoagulation for atrial fibrillation (AF), heart failure (HF) is associated with poor anticoagulation control. However, it is not known which patients with heart failure are at greatest risk of adverse outcomes. We evaluated 62,156 Veterans Health Administration (VA) patients receiving warfarin for AF between 10/1/06-9/30/08 using merged VA-Medicare dataset. We predicted time in therapeutic range (TTR) and rates of adverse events by categorising patients into those with 0, 1, 2, or 3+ of five putative markers of HF severity such as aspartate aminotransferase (AST)> 80 U/l, alkaline phosphatase> 150 U/l, serum sodium< 130 mEq/l, any receipt of metolazone, and any inpatient admission for HF exacerbation. These risk categories predicted TTR: patients without HF (referent) had a mean TTR of 65.0 %, while HF patients with 0, 1, 2, 3 or more markers had mean TTRs of 62.2 %, 57.2 %, 53.5 %, and 50.7 %, respectively (p< 0.001). These categories also discriminated for major haemorrhage well; compared to patients without HF, HF patients with increasing severity had hazard ratios of 1.84, 3.06, 3.52 and 5.14 respectively (p< 0.001). However, although patients with HF had an elevated hazard for bleeding compared to those without HF, these categories did not effectively discriminate risk of ischaemic stroke across HF. In conclusion, we developed a HF severity model using easily available clinical characteristics that performed well to risk-stratify patients with HF who are receiving anticoagulation for AF with regard to major haemorrhage.

Aquaporins, vasopressin, and aging: current perspectives

Functioning of the hypothalamic-neurohypophyseal-vasopressin axis is altered in aging, and the pathway may represent a plausible target to slow the process of aging. Arginine vasopressin, a nine-amino acid peptide that is secreted from the posterior pituitary in response to high plasma osmolality and hypotension, is central in this pathway. Vasopressin has important roles in circulatory and water homoeostasis mediated by vasopressin receptor subtypes V1a (vascular), V1b (pituitary), and V2 (vascular, renal). A dysfunction in this pathway as a result of aging can result in multiple abnormalities in several physiological systems. In addition, vasopressin plasma concentration is significantly higher in males than in females and vasopressin-mediated effects on renal and vascular targets are more pronounced in males than in females. These findings may be caused by sex differences in vasopressin secretion and action, making men more susceptible than females to diseases like hypertension, cardiovascular and chronic kidney diseases, and urolithiasis. Recently the availability of new, potent, orally active vasopressin receptor antagonists, the vaptans, has strongly increased the interest on vasopressin and its receptors as a new target for prevention of age-related diseases associated with its receptor-altered signaling. This review summarizes the recent literature in the field of vasopressin signaling in age-dependent abnormalities in kidney, cardiovascular function, and bone function.

Survival on biventricular mechanical support with the Centrimag® as a bridge to decision: a single-center risk stratification

Objective:

Temporary mechanical assist devices are increasingly being used as a lifesaving bridge to decision in patients requiring cardiopulmonary resuscitation. We report our single-center experience with biventricular Centrimag® pumps over a five-year period.

Method:

Data was retrospectively collected in consecutive patients who required biventricular support from 2008 to 2013. Patients who were supported with central cannulation using the Centrimag® system were analyzed. In addition to demographic information, data pertaining to indications, outcomes and mortality were collected.

Results:

The cohort consisted of 48 patients (19 women and 29 men, mean age of 56 years). The median duration of support was 14 days. The median duration to patient expiration while still on the Centrimag® was 12 days. Thirty-day survival was 56% (27/48). Nine patients were explanted to recovery, while fourteen patients were converted to a durable LVAD, two of whom were then transplanted. We stratified patients into two groups. Group I comprised patients who were either explanted to recovery, converted to durable LVAD or transplanted (23/48) and Group II consisted of patients who either died on the Centrimag® or were explanted for withdrawal of care (25/48). Statistical analysis did not reveal any clinically significant differences between the two groups in terms of age, sex, etiology, hemodynamic, co-morbidities or laboratory parameters.

Conclusion:

The biventricular Centrimag® can be used as a bridge to decision in patients with thirty-day survival of >50%. Parameters to predict 30-day survival in this high-risk cohort continue to remain elusive.

Hepatic dysfunction in ambulatory patients with heart failure: application of the MELD scoring system for outcome prediction

OBJECTIVES

This study evaluated the Model for End-Stage Liver Disease (MELD) score and its modified versions, which are established measures of liver dysfunction, as a tool to assess heart transplantation (HTx) urgency in ambulatory patients with heart failure.

BACKGROUND

Liver abnormalities have a prognostic impact on the outcome of patients with advanced heart failure.

METHODS

We retrospectively evaluated 343 patients undergoing HTx evaluation between 2005 and 2009. The prognostic effectiveness of MELD and 2 modifications (MELDNa [includes serum sodium levels] and MELD-XI [does not include international normalized ratio]) for endpoint events, defined as death/HTx/ventricular assist device requirement, was evaluated in our cohort and in subgroups of patients on and off oral anticoagulation.

RESULTS

The MELD and MELDNa scores were excellent predictors for 1-year endpoint events (areas under the curve: 0.71 and 0.73, respectively). High scores (>12) were strongly associated with poor survival at 1 year (MELD 69.3% vs. 90.4% [p < 0.0001]; MELDNa 70.4% vs. 96.9% [p < 0.0001]). Increased scores were associated with increased risk for HTx (hazard ratio: 1.10 [95% confidence interval: 1.06 to 1.14]; p < 0.0001 for both scores), which was independent of other known risk factors (MELD p = 0.0055; MELDNa p = 0.0083). Anticoagulant use was associated with poor survival at 1 year (73.7% vs. 86.4%; p = 0.0118), and the statistical significance of MELD/MELDNa was higher in patients not receiving oral anticoagulation therapy. MELD-XI was a fair but limited predictor of the endpoint events in patients receiving oral anticoagulation therapy.

CONCLUSIONS

Assessment of liver dysfunction according to the MELD scoring system provides additional risk information in ambulatory patients with heart failure.

Healthcare resource burden associated with hyponatremia among patients hospitalized for heart failure in the US

OBJECTIVE

To evaluate the burden of hyponatremia in terms of hospital resource utilization, costs, and 30-day hospital readmission among patients hospitalized for heart failure (HF) in routine clinical practice.

METHODS

Hyponatremic (HN) patients (≥18 years of age) with HF discharged between January 2, 2007 and March 31, 2010 were selected from the Premier Hospital Database and matched to non-HN HF patients using exact and propensity score matching. Univariate and multivariate statistics were utilized to compare hospital resource utilization (total and intensive care unit (ICU)) and associated costs and 30-day hospital readmission among cohorts.

RESULTS

The study population included 51,710 subjects (HN = 25,855, non-HN = 25,855). In comparison to the non-HN cohort, length of stay (LOS) (7.7 ± 8.3 vs 6.3 ± 7.6 days, p < 0.001), hospitalization cost ($13,339 ± $19,273 vs $10,475 ± 15,157, p < 0.001), ICU LOS (4.9 ± 5.4 vs 4.2 ± 5.4 days, p < 0.001) and ICU cost ($7195 ± $9522 vs $5618 ± 10,919, p < 0.001) as well as rate of 30-day readmission (all cause: 25.3% vs 22.2%, p < 0.001; hyponatremia-related: 21.4% vs 5.0%, p < 0.001) were greater for the HN cohort. After adjustment, hyponatremia was associated with a 21.5% increase in hospital LOS, a 25.6% increase in hospital cost, a 13.7% increase in ICU LOS and a 24.6% increase in ICU cost. Additionally, hyponatremia was associated with increased risk of ICU admission (Odds Ratio (OR) = 1.58, [CI = 1.37, 1.84], p < 0.001) and 30-day hospital readmission (all cause: OR = 1.19, [CI = 1.14, 1.24], p < 0.001; hyponatremia-related: 5.10 [CI = 4.77, 5.46], p < 0.001).

LIMITATIONS

Laboratory data for serum sodium level are not available in the Premier database and the severity of hyponatremia could not be established, although several patient variables were controlled for in this study by exact and propensity score matching techniques.

CONCLUSIONS

Hyponatremia in HF patients is a predictor of increased hospital resource use and represents a potential target for intervention to reduce healthcare expenditures.

Hyponatremia, acute kidney injury, and mortality in HIV-related toxoplasmic encephalitis

BACKGROUND

There are no reports on hyponatremia and acute kidney injury (AKI) involved in the course of HIV-related toxoplasmic encephalitis (TE). The main objective of this study was to describe the occurrence of hyponatremia and its relationship with AKI and mortality in HIV-related toxoplasmic encephalitis (TE).

METHODS

This was a retrospective cohort study on patients with HIV-related TE. AKI was considered only when the RIFLE (risk, injury, failure, loss, end-stage) criterion was met, after the patient was admitted.

RESULTS

A total of 92 patients were included, with a mean age of 36±9 years. Hyponatremia at admission was observed in 43 patients (46.7%), with AKI developing in 25 (27.1%) patients during their hospitalization. Sulfadiazine was the treatment of choice in 81% of the cases. Death occurred in 13 cases (14.1%). Low serum sodium level correlated directly with AKI and mortality. Male gender (OR 7.89, 95% CI 1.22-50.90, p = 0.03) and hyponatremia at admission (OR 4.73, 95% CI 1.22-18.30, p = 0.02) were predictors for AKI. Independent risk factors for death were AKI (OR 8.3, 95% CI 1.4-48.2, p < 0.0001) and hyponatremia (OR 9.9, 95% CI 1.2-96.3, p < 0.0001).

CONCLUSION

AKI and hyponatremia are frequent in TE. Hyponatremia on admission is highly associated with AKI and mortality.