Hyponatremia predicts right heart failure and poor survival in pulmonary arterial hypertension

Risk stratification and treatment goals in pulmonary arterial hypertension

Risk stratification has gained an increasing role in predicting outcomes and guiding the treatment of patients with pulmonary arterial hypertension (PAH). The most predictive prognostic factors are three noninvasive parameters (World Health Organization functional class, 6-min walk distance and natriuretic peptides) that are included in all currently validated risk stratification tools. However, suffering from limitations mainly related to reduced specificity of PAH severity, these variables may not always be adequate in isolation for guiding individualised treatment decisions. Moreover, with effective combination treatment regimens and emerging PAH therapies, markers associated with pulmonary vascular remodelling are expected to become of increasing relevance in guiding the treatment of patients with PAH. While reaching a low mortality risk, assessed with a validated risk tool, remains an important treatment goal, preliminary data suggest that invasive haemodynamics and cardiac imaging may add incremental value in guiding treatment decisions.

Kidney Dysfunction, Hepatic Impairment, and Lipid Metabolism Abnormalities in Patients with Precapillary Pulmonary Hypertension

BACKGROUND

Pulmonary hypertension (PH) is a global health issue that has profound medical and research implications.

METHODS

This retrospective study examined changes in renal and liver function, as well as lipid metabolism, over a 12-month period in 49 adult patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). All cases were admitted, managed, and followed up with in the PH Center, County Emergency Clinical Hospital of Targu Mures, Romania.

RESULTS

Kidney dysfunction was observed in 12.24% of cases at baseline, decreasing to 8.16% at 12 months, and CTEPH patients were more affected. In particular, CTEPH patients exhibited an improvement in renal function, confirmed by an increase in their glomerular filtration rates. Hepatic impairment was present in 57.14% of subjects at baseline, declining to 42.86% at 12 months, with significant improvements noted in the PAH group. Lipid metabolic dysregulations were experienced by 22.45% of all patients at baseline, decreasing to 16.33% at 6 months, with a slow elevation to 24.49% at 12 months, but with no statistically significant differences. Pharmacological regimens were adjusted in accordance with the PH groups, a patient's functional and clinical response, and laboratory tests.

CONCLUSIONS

Our results demonstrate the multi-organ damage in PH and the importance of individualized treatment approaches.

The role of serum sodium in poor prognosis evaluation of pulmonary hypertension associated with left heart disease

BACKGROUND

Previous studies have shown that hyponatremia was strongly associated with a poor prognosis of type 1 pulmonary hypertension, and our team's antecedent studies found that low serum sodium was associated with the severity and the length of hospitalization of pulmonary hypertension associated with left ventricular disease (PH-LHD). However, the relationship between serum sodium and the prognosis of PH-LHD remains unclear. This study aims to determine the clinical value of serum sodium in evaluating poor prognosis in patients with PH-LHD.

METHODS

We successfully followed 716 patients with PH-LHD. Kaplan-Meier was used to plot survival in PH-LHD patients with different serum sodium levels. The effect of serum sodium on poor prognosis was analyzed using a Cox proportional risk model. The trends between patients serum sodium and survival were visualized by restricted cubic spline (RCS).

RESULTS

The survival rates at 1, 2, 3 and 4 years were 52%, 41%, 31% and 31% for the patients with hyponatremia associated with PH-LHD and 71%, 71%, 71% and 54% for the patients with hypernatremia, respectively. The observed mortality rate in the hyponatremia and hypernatremia groups surpassed that of the normonatremic group. The adjusted risks of death (risk ratio) for patients with hyponatremia and hypernatremia were found to be 2.044 and 1.877. Furthermore, the restricted cubic spline demonstrated an L-shaped correlation between serum sodium and all-cause mortality in patients with PH-LHD.

CONCLUSIONS

Abnormal serum sodium level is strongly associated with poor prognosis in PH-LHD. Serum sodium may play an important pathogenic role in PH-LHD occurrence and could be used as a marker to assess the survival in patients.

Clinical features of pulmonary arterial hypertension associated with systemic sclerosis

Systemic sclerosis is an autoimmune disorder of the connective tissue characterized by disordered inflammation and fibrosis leading to skin thickening and visceral organ complications. Pulmonary involvement, in the form of pulmonary arterial hypertension and/or interstitial lung disease, is the leading cause of morbidity and mortality among individuals with scleroderma. There are no disease-specific therapies for pulmonary involvement of scleroderma, and pulmonary arterial hypertension in this cohort has typically been associated with worse outcomes and less clinical response to modern therapy compared to other forms of Group I pulmonary hypertension in the classification from the World Symposium on Pulmonary Hypertension. Ongoing research aims to delineate how pathologic microvascular remodeling and fibrosis contribute to this poor response and offer a window into future therapeutic targets.

Hepatorenal dysfunction in patients with chronic thromboembolic pulmonary hypertension

Background

Cardiac interactions with organs such as the liver or kidneys have been described in different cardiovascular diseases. However, the clinical relevance of hepatorenal dysfunction in chronic thromboembolic pulmonary hypertension (CTEPH) remains unclear. We determined the association of hepatorenal dysfunction (measured using the Model for End-stage Liver Disease Sodium [MELDNa] score) with right heart function and survival in patients with CTEPH.

Methods

We analyzed all patients with CTEPH in the Giessen Pulmonary Hypertension Registry who had available MELDNa scores and were not taking vitamin K antagonists. The MELDNa score was calculated as MELD score - serum Na - (0.025 * MELD score * (140 - serum Na)) + 140; the MELD score was calculated as 10*(0.957*ln(creatinine)+0.378*ln(bilirubin)+1.12*ln(International Normalized Ratio))+6.43.

Results

Seventy-two patients were included (74% female; median [Q1, Q3] MELDNa: 9 [6, 11]). MELDNa correlated well with right atrial and ventricular function and pulmonary hemodynamics. Forward regression analysis revealed that hepatorenal dysfunction mainly depends on right atrial strain and tricuspid regurgitation, but not right ventricular systolic dysfunction. Hepatorenal dysfunction predicted mortality at baseline and follow-up (adjusted hazard ratios [95% confidence intervals] per unit increase of MELDNa: 1.6 [1.1, 2.4] and 1.8 [1.1, 2.9], respectively). Changes in hepatorenal function also predicted mortality.

Conclusion

Hepatorenal dysfunction in CTEPH is primarily associated with venous congestion rather than cardiac forward failure. As a surrogate parameter for hepatorenal dysfunction, MELDNa is a simple method to identify at-risk patients at baseline and follow-up.

Pathophysiology and new advances in pulmonary hypertension

Pulmonary hypertension is a progressive and often fatal cardiopulmonary condition characterised by increased pulmonary arterial pressure, structural changes in the pulmonary circulation, and the formation of vaso-occlusive lesions. These changes lead to increased right ventricular afterload, which often progresses to maladaptive right ventricular remodelling and eventually death. Pulmonary arterial hypertension represents one of the most severe and best studied types of pulmonary hypertension and is consistently targeted by drug treatments. The underlying molecular pathogenesis of pulmonary hypertension is a complex and multifactorial process, but can be characterised by several hallmarks: inflammation, impaired angiogenesis, metabolic alterations, genetic or epigenetic abnormalities, influence of sex and sex hormones, and abnormalities in the right ventricle. Current treatments for pulmonary arterial hypertension and some other types of pulmonary hypertension target pathways involved in the control of pulmonary vascular tone and proliferation; however, these treatments have limited efficacy on patient outcomes. This review describes key features of pulmonary hypertension, discusses current and emerging therapeutic interventions, and points to future directions for research and patient care. Because most progress in the specialty has been made in pulmonary arterial hypertension, this review focuses on this type of pulmonary hypertension. The review highlights key pathophysiological concepts and emerging therapeutic directions, targeting inflammation, cellular metabolism, genetics and epigenetics, sex hormone signalling, bone morphogenetic protein signalling, and inhibition of tyrosine kinase receptors.

Acute Right Ventricular Failure: Pathophysiology, Diagnostic Approach with Emphasis on the Role of Echocardiography

Right ventricular function is one of the important predictors of survival in heart failure patients. In the past, there has been only limited knowledge regarding right-sided heart failure when compared to left-sided failure. However, there are more emerging data in recent years, and several studies have emphasized the unique features of the right ventricle regarding its anatomy, pathophysiology, clinical consequences, diagnostic modalities, and treatment options. Despite that, management of acute right ventricular failure is still challenging. This article summarizes an overview of acute right heart failure including pathophysiology, causes, clinical features, and diagnostic work-up with emphasis on the role of echocardiography.

Metabolomic Profiles Differentiate Scleroderma-PAH From Idiopathic PAH and Correspond With Worsened Functional Capacity

BACKGROUND

The prognosis and therapeutic responses are worse for pulmonary arterial hypertension associated with systemic sclerosis (SSc-PAH) compared with idiopathic pulmonary arterial hypertension (IPAH). This discrepancy could be driven by divergence in underlying metabolic determinants of disease.

RESEARCH QUESTION

Are circulating bioactive metabolites differentially altered in SSc-PAH vs IPAH, and can this alteration explain clinical disparity between these PAH subgroups?

STUDY DESIGN AND METHODS

Plasma biosamples from 400 patients with SSc-PAH and 1,082 patients with IPAH were included in the study. Another cohort of 100 patients with scleroderma with no PH and 44 patients with scleroderma with PH was included for external validation. More than 700 bioactive lipid metabolites, representing a range of vasoactive and immune-inflammatory pathways, were assayed in plasma samples from independent discovery and validation cohorts using liquid chromatography/high-resolution mass spectrometry-based approaches. Regression analyses were used to identify metabolites that exhibited differential levels between SSc-PAH and IPAH and associated with disease severity.

RESULTS

From hundreds of circulating bioactive lipid molecules, five metabolites were found to distinguish between SSc-PAH and IPAH, as well as associate with markers of disease severity. Relative to IPAH, patients with SSc-PAH carried increased levels of fatty acid metabolites, including lignoceric acid and nervonic acid, as well as eicosanoids/oxylipins and sex hormone metabolites.

INTERPRETATION

Patients with SSc-PAH are characterized by an unfavorable bioactive metabolic profile that may explain the poor and limited response to therapy. These data provide important metabolic insights into the molecular heterogeneity underlying differences between subgroups of PAH.

Postoperative tolvaptan use in left ventricular assist device patients: The TOLVAD randomized pilot study

PURPOSE

Tolvaptan, a selective vasopressin type-2 antagonist, has been shown to increase serum sodium (Na) and urine output in hyponatremic left ventricular assist device (LVAD) patients in retrospective studies. In this prospective randomized pilot study, we aimed to assess the efficacy of tolvaptan in this population.

METHODS

We conducted a prospective, randomized, non-blinded pilot study of LVAD recipients with post-operative hyponatremia (Na < 135 mEq/L) (NCT05408104). Eligible participants were randomized to receive tolvaptan 15 mg daily in addition to usual care versus usual care alone. The primary outcome was a change in Na level and estimated glomerular filtration rate (eGFR), from the first post-operative day of hyponatremia (the day of randomization) to discharge.

RESULTS

A total of 33 participants were enrolled, and 28 underwent randomization (median age 55 [IQR 50-62]), 21% women, 54% Black, 32% ischemic cardiomyopathy, median baseline Na 135 (IQR 134-138). Fifteen participants were randomized to tolvaptan (TLV) and 13 were randomized to usual care alone (No-TLV). Mean change in Na from randomization to discharge in the TLV group was 2.7 mEq/L (95%CI 0.7-4.7, p = 0.013) and 1.8 (95%CI 0.5-4.0, p = 0.11) in the No-TLV group, though baseline and final Na levels were similar between groups. The mean change in eGFR was 2.6 ml/min/1.73 m2 (95%CI 10.1-15.3, p = 0.59) in TLV versus 7.5 ml/min/1.73 m2 (95%CI 5.2-20.2, p = 0.15) in No-TLV. TLV participants had significantly more urine output than No-TLV patients during their first 24 h after randomization (3294 vs 2155 ml, p = 0.043).

CONCLUSION

TLV significantly increases urine output, with nominal improvement in Na level, in hyponatremic post-operative LVAD patients without adversely impacting renal function.

Impact of Estimated Plasma Volume Status on Mortality in Right Heart Failure Patients: A Retrospective Cohort Study in Indonesia

Background:

Plasma volume (PV) expansion hallmarks the syndrome of heart failure (HF) but is difficult to be quantified noninvasively. Estimated plasma volume status (ePVS) has marked prognostic utility in the failing left heart, however its use in right heart failure (RHF) remains unknown. This study aims to investigate the prognostic value of ePVS among isolated RHF patients.

Methods:

We retrospectively collected 208 patients admitted for RHF in our hospital from the electronic database from 2017 to 2019. ePVS was calculated using the Hakim formula. Patients were divided into low and high groups based on their PV value. Logistic regression was used to compare the odds of in-hospital mortality between these groups.

Results:

The overall in-hospital mortality was 12.5%, tripled from the low group to the high group (6.7% vs. 18.3%), within a median of 6 (3–19) days. High ePVS significantly predicted mortality in RHF, even after being adjusted for demographic, hemodynamic, chemistry, and medication variables (adjusted OR: 5.83, 95% CI: 1.62–20.95, p < 0.01).

Conclusion:

ePVS is associated with in-hospital mortality among isolated RHF patients. Given not only the wide accessibility of hemogram but also the low cost and the rapid quantification of relative PV, this simple tool can potentially aid in optimizing RHF management, especially in rural area, although further evaluation is warranted.

Preoperative hyponatremia and survival after left ventricular assist device implantation

BACKGROUND

Hyponatremia is associated with adverse outcomes in heart failure and after cardiac surgery. We hypothesized that hyponatremia is associated with poorer short-term and longer-term survival in patients after continuous-flow left ventricular assist device (CF-LVAD) placement.

METHODS

We reviewed a single-center database of patients who received a CF-LVAD during 2012-2017. Sodium (Na) values obtained within 14 days before CF-LVAD insertion were averaged; patients (n=332) were divided into hyponatremia (mean Na <135 mEq/L; n=160; 48.2%) and normonatremia groups (mean Na 135-145 mEq/L; n=172; 51.8%). Patients requiring preoperative dialysis or pump exchanged were excluded. We compared outcomes between preoperative hyponatremia and normonatremia groups.

RESULTS

The two groups' baseline characteristics were similar, although hyponatremia patients more often had preoperative mechanical circulatory support (44.4% vs 31.4%, p=0.002). Although hyponatremic and normonatremic patients did not differ in 30-day mortality (7.5% vs 6.5%, p=0.7), preoperative hyponatremia was associated with greater 5-year mortality (61% vs 44%, p=0.03). On binary logistic regression analysis, the strongest independent predictors of late mortality were hyponatremia (odds ratio [OR] 1.88, 95% CI [1.07-3.31], p=0.02), older age (OR 1.03, 95% CI [1.01-1.05], p=0.01), and elevated mean right atrial pressure/pulmonary capillary wedge pressure ratio (OR 4.69, 95% CI [1.76-12.47], p=0.002).

CONCLUSIONS

Hyponatremia was not associated with greater early mortality but was associated with poorer late survival. Optimal timing of LVAD implantation in relation to hyponatremia, and whether correcting hyponatremia perioperatively improves long-term survival, should be investigated.

Relationships between sodium levels, haemodynamics and metalloproteinases in heart failure patients

To estimate the associations between dysnatraemia and inflammatory marker [including interleukin-6 (IL-6)], and tissue remodelling marker [matrix metalloproteinase (MMP)-9 and tissue inhibitor of MMP (TIMP)-1], the pulmonary capillary wedge pressure (PCWP), mean pulmonary artery pressure (PAP), and left ventricular end-diastolic pressure (EDP), and the prognostic relevance in patients with heart failure. The serum sodium level and circulating levels of IL-6, MMP-9, and TIMP-1 were measured in 173 heart failure patients. Dual heart catheterisation was performed to measure PCWP, mean PAP, and EDP. All-cause mortality was assessed during the follow-up period (mean 88 ± 49 months). Restricted cubic spline (RCS) regression showed a U-shaped association of serum sodium level with TIMP-1, with the lowest values in the 138-140 mmol/L range (P for effect = 0.042, P for non-linearity = 0.017). IL-6 and MMP-9 levels showed non-significant associations with serum sodium level. U-shaped associations of serum sodium level with PCWP (P for effect = 0.004, P for non-linearity = 0.001) and mean PAP (P for effect = 0.042, P for non-linearity = 0.017) were found with the RCS regression model. The random forest model revealed that TIMP-1, MMP-9, and IL-6 were important predictors for serum sodium levels. Restricted cubic spline Cox regressions demonstrated that TIMP-1 levels indicated a U-shaped, concaved, non-linear association with all-cause mortality (P for effect = 0.011, P for non-linearity = 0.022). Dysnatraemia is an index of TIMP-1 aggravation and elevated PCWP, mean PAP; hence, it is associated with worsening all-cause mortality.Clinical Trial Registration: UMIN000023840.

Right ventricular failure: a comorbidity or a clinical emergency?

There has been ample data providing a convincing perception about the underlying mechanism pertaining to left ventricle (LV) hypertrophy progressing towards LV failure. In comparison, data available on the feedback of right ventricle (RV) due to volume or pressure overload is minimal. Advanced imaging techniques have aided the study of physiology, anatomy, and diseased state of RV. However, the treatment scenario of right ventricular failure (RVF) demands more attention. It is a critical clinical risk in patients with carcinoid syndrome, pulmonary hypertension, atrial septal defect, and several other concomitant diseases. Although the remodeling responses of both ventricles on an increase of end-diastolic pressure are mostly identical, the stressed RV becomes more prone to oxidative stress activating the apoptotic mechanism with diminished angiogenesis. This instigates the advancement of RV towards failure in contrast to LV. Empirical heart failure (HF) therapies have been ineffective in improving the mortality rate and cardiac function in patients, which prompted a difference between the underlying pathophysiology of RVF and LV failure. Treatment strategies should be devised, taking into consideration the anatomical and physiological characteristics of RV. This review would emphasize on the pathophysiology of the RVF and the differences between two ventricles in molecular response to stress. A proper insight into the underlying pathophysiology is required to develop optimized therapeutic management in RV-specific HF.

The prevalence and prognosis of hyponatraemia in non-Hodgkin lymphoma-associated hemophagocytic lymphohistiocytosis

Non-Hodgkin lymphoma associated hemophagocytic lymphohistiocytosis (NHL-HLH) in adult secondary HLH is a common and universally highly lethal critical disorder. Hyponatraemia is the most common electrolyte disorder in the critical illness setting and acts as a negative prognostic factor. The aim of our study was to evaluate the prognostic role of hyponatraemia among patients with NHL-HLH. The results showed that 81 (52.9%) patients had hyponatraemia. After a median follow up 47 (range 14-180) days, there were 72 (88.9%) cumulative deaths in hyponatraemia group while 50 (69.4%) in normonatremia group. After adjustment for confounders, multivariate analysis revealed that hyponatraemia was an independent prognostic factor for OS (HR:1.51, 95% CI: 1.03-2.20; p = 0.033). Restricted cubic spline confirmed a linear and positive association between serum sodium and the risk of mortality. Hyponatraemia is relatively frequent in NHL-HLH. As a readily available biomarker in clinical routine, it was a promising prognostic predictor for NHL-HLH.

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.

Systemic Sclerosis-Associated Pulmonary Hypertension: Spectrum and Impact

Systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) is a catastrophic complication of one of the most common and devastating autoimmune diseases. Once diagnosed, it becomes the leading cause of mortality among this patient population. Screening modalities and risk assessments have been designed and validated by various organizations and societies in order to identify patients early in their disease course and promptly refer them to expert centers for a hemodynamic assessment and formal diagnosis. Moreover, several large multicenter clinical trials have now included patients with SSc-PAH to assess their response to therapy. Despite an improved understanding of the condition and significant advances in supportive and targeted therapy, outcomes have remained far from optimal. Therefore, rigorous phenotyping and search for novel therapies are desperately needed for this devastating condition.

Critical care outcomes in patients with pre-existing pulmonary hypertension: insights from the ASPIRE registry

Pulmonary hypertension (PH) is a life-shortening condition characterised by episodes of decompensation precipitated by factors such as disease progression, arrhythmias and sepsis. Surgery and pregnancy also place additional strain on the right ventricle. Data on critical care management in patients with pre-existing PH are scarce.

We conducted a retrospective observational study of a large cohort of patients admitted to the critical care unit of a national referral centre between 2000–2017 to establish acute mortality, evaluate predictors of in-hospital mortality and establish longer term outcomes in survivors to hospital discharge.

242 critical care admissions involving 206 patients were identified. Hospital survival was 59.3%, 94% and 92% for patients admitted for medical, surgical or obstetric reasons, respectively. Medical patients had more severe physiological and laboratory perturbations than patients admitted following surgical or obstetric interventions. Higher APACHE II (Acute Physiology and Chronic Health Evaluation) score, age and lactate, and lower oxygen saturation measure by pulse oximetry/inspiratory oxygen fraction (S_pO2/F_iO2) ratio, platelet count and sodium level were identified as independent predictors of hospital mortality. An exploratory risk score, OPALS (oxygen (S_pO2/F_iO2) ≤185; platelets ≤196×10⁹·L⁻¹; age ≥37.5 years; lactate ≥2.45 mmol·L⁻¹; sodium ≤130.5 mmol·L⁻¹), identified medical patients at increasing risk of hospital mortality. One (11%) out of nine patients who were invasively ventilated for medical decompensation and 50% of patients receiving renal replacement therapy left hospital alive. There was no significant difference in exercise capacity or functional class between follow-up and pre-admission in patients who survived to discharge.

These data have clinical utility in guiding critical care management of patients with known PH. The exploratory OPALS score requires validation.

Critical care survival is worse in PH patients admitted for medical rather than surgical/obstetric indications. Nevertheless, many show longer term survival and functional recovery. Markers of severity of acute illness at admission are prognostic.https://bit.ly/2YX9Fw9

Safety and Efficacy of B-Cell Depletion with Rituximab for the Treatment of Systemic Sclerosis-associated Pulmonary Arterial Hypertension: A Multicenter, Double-Blind, Randomized, Placebo-controlled Trial

Rationale: Systemic sclerosis (SSc)-pulmonary arterial hypertension (PAH) is one of the most prevalent and deadly forms of PAH. B cells may contribute to SSc pathogenesis. Objectives: We investigated the safety and efficacy of B-cell depletion for SSc-PAH. Methods: In an NIH-sponsored, multicenter, double-blinded, randomized, placebo-controlled, proof-of-concept trial, 57 patients with SSc-PAH on stable-dose standard medical therapy received two infusions of 1,000 mg rituximab or placebo administered 2 weeks apart. The primary outcome measure was the change in 6-minute-walk distance (6MWD) at 24 weeks. Secondary endpoints included safety and invasive hemodynamics. We applied a machine learning approach to predict drug responsiveness. Measurements and Main Results: We randomized 57 subjects from 2010 to 2018. In the primary analysis, using data through Week 24, the adjusted mean change in 6MWD at 24 weeks favored the treatment arm but did not reach statistical significance (23.6 ± 11.1 m vs. 0.5 ± 9.7 m; P = 0.12). Although a negative study, when data through Week 48 were also considered, the estimated change in 6MWD at Week 24 was 25.5 ± 8.8 m for rituximab and 0.4 ± 7.4 m for placebo (P = 0.03). Rituximab treatment appeared to be safe and well tolerated. Low levels of RF (rheumatoid factor), IL-12, and IL-17 were sensitive and specific as favorable predictors of a rituximab response as measured by an improved 6MWD (receiver operating characteristic area under the curve, 0.88-0.95). Conclusions: B-cell depletion therapy is a potentially effective and safe adjuvant treatment for SSc-PAH. Future studies in these patients can confirm whether the identified biomarkers predict rituximab responsiveness. Clinical trial registered with www.clinicaltrails.gov (NCT01086540).

Hyponatremia-Long-Term Prognostic Factor for Nonfatal Pulmonary Embolism

Over recent years, studies have shown that in patients with left-sided heart failure, arterial hypertension, and acute coronary syndrome, hyponatremia is a negative prognostic factor. In this context, there is raising interest in the association between hyponatremia and pulmonary embolism (PE). This retrospective cohort study includes 404 consecutive patients with confirmed acute nonfatal pulmonary embolism divided into four groups according to their sodium fluctuation pattern. The primary outcome was all-cause mortality and determining the recurrence rate among patients with nonfatal PE using serum sodium levels as a continuous variable. Patients with acquired and persistent hyponatremia had a significantly higher rate of mortality rate than those in the normonatremia group (12.8% and 40.4%, OR- 7.206, CI: 2.383-21.791, p = 0.000 and OR-33.250, CI: 11.521-95.960, p = 0.000 vs. 2%, p < 0.001, respectively). Mean survival time decreases from 23.624 months (95% CI: (23.295-23.953)) in the normonatremia group to 16.426 months (95% CI: (13.17-19.134)) in the persistent hyponatremia group, statistically significant (p = 0.000). The mean survival time for all patients was 22.441 months (95% CI: (21.930-22.951)). The highest recurrence rate was recorded at 12 and 24 months in the acquired hyponatremia group (16.7% and 14.1%, respectively). Serum sodium determination is a simple and cost-effective approach in evaluating the short and long-term prognosis in patients with acute PE.

Lower Plasma Melatonin Levels Predict Worse Long-Term Survival in Pulmonary Arterial Hypertension

Exogenous melatonin has been reported to be beneficial in the treatment of pulmonary hypertension (PH) in animal models. Multiple mechanisms are involved, with melatonin exerting anti-oxidant and anti-inflammatory effects, as well as inducing vasodilation and cardio-protection. However, endogenous levels of melatonin in treatment-naïve patients with PH and their clinical significance are still unknown. Plasma levels of endogenous melatonin were measured by liquid chromatography-tandem mass spectrometry in PH patients (n = 64, 43 pulmonary arterial hypertension (PAH) and 21 chronic thromboembolic PH (CTEPH)) and healthy controls (n = 111). Melatonin levels were higher in PH, PAH, and CTEPH patients when compared with controls (Median 118.7 (IQR 108.2–139.9), 118.9 (109.3–147.7), 118.3 (106.8–130.1) versus 108.0 (102.3–115.2) pM, respectively, p all <0.001). The mortality was 26% (11/43) in the PAH subgroup during a long-term follow-up of 42 (IQR: 32–58) months. Kaplan–Meier analysis showed that, in the PAH subgroup, patients with melatonin levels in the 1st quartile (<109.3 pM) had a worse survival than those in quartile 2–4 (Mean survival times were 46 (95% CI: 30–65) versus 68 (58–77) months, Log-rank, p = 0.026) with an increased hazard ratio of 3.5 (95% CI: 1.1–11.6, p = 0.038). Endogenous melatonin was increased in treatment-naïve patients with PH, and lower levels of melatonin were associated with worse long-term survival in patient with PAH.

Hypochloremia Is a Noninvasive Predictor of Mortality in Pulmonary Arterial Hypertension

Background

Pulmonary arterial hypertension (PAH) is a lethal disease. In resource‐limited countries PAH outcomes are worse because therapy costs are prohibitive. To improve global outcomes, noninvasive and widely available biomarkers that identify high‐risk patients should be defined. Serum chloride is widely available and predicts mortality in left heart failure, but its prognostic utility in PAH requires further investigation.

Methods and Results

In this study 475 consecutive PAH patients evaluated at the University of Minnesota and Vanderbilt University PAH clinics were examined. Clinical characteristics were compared by tertiles of serum chloride. Both the Kaplan‐Meier method and Cox regression analysis were used to assess survival and predictors of mortality, respectively. Categorical net reclassification improvement and relative integrated discrimination improvement compared prediction models. PAH patients in the lowest serum chloride tertile (≤101 mmol/L: hypochloremia) had the lowest 6‐minute walk distance and highest right atrial pressure despite exhibiting no differences in pulmonary vascular disease severity. The 1‐, 3‐, and 5‐year survival was reduced in hypochloremic patients when compared with the middle‐ and highest‐tertile patients (86%/64%/44%, 95%/78%/59%, and, 91%/79%/66%). After adjustment for age, sex, diuretic use, serum sodium, bicarbonate, and creatinine, the hypochloremic patients had increased mortality when compared with the middle‐tertile and highest‐tertile patients. The Minnesota noninvasive model (functional class, 6‐minute walk distance, and hypochloremia) was as effective as the French noninvasive model (functional class, 6‐minute walk distance, and elevated brain natriuretic peptide or N‐terminal pro–brain natriuretic peptide) for predicting mortality.

Conclusions

Hypochloremia (≤101 mmol/L) identifies high‐risk PAH patients independent of serum sodium, renal function, and diuretic use.

Hyponatremia Associated with Pulmonary Arterial Hypertension: Syndrome of Inappropriate Antidiuresis Versus Right Heart Failure

Because it is associated with mortality, hyponatremia is an important feature of pulmonary arterial hypertension. Its mechanisms remain unclear, although right heart failure resulting from pulmonary arterial hypertension may lead to systemic congestion and arterial underfilling. However, most patients with pulmonary arterial hypertension are clinically euvolemic and have no peripheral edema. Unlike patients with underlying heart disease, neurohumoral activation is not demonstrated in hyponatremic patients with pulmonary arterial hypertension, who show features of congestive heart failure only at later stages in their disease. Here, a case vignette is introduced, and the pathophysiology of hyponatremia in pulmonary arterial hypertension will be discussed. Syndrome of inappropriate antidiuresis (SIAD) appears to underlie hyponatremia in the initial phase of pulmonary arterial hypertension. The mechanisms by which various lung diseases can lead to SIAD remain an enigma.

The Use of Risk Assessment Tools and Prognostic Scores in Managing Patients with Pulmonary Arterial Hypertension

PURPOSE OF REVIEW

Pulmonary arterial hypertension (PAH) is a chronic, progressive, and incurable disease with significant morbidity and mortality. Despite increasingly available treatment options, PAH patients continue to experience disease progression and increased rates of hospitalizations due to right heart failure. Physician's ability to comprehensively assess PAH patients, determine prognosis, and monitor disease progression and response to treatment remains critical in optimizing outcomes.

RECENT FINDINGS

Risk assessment in PAH should include a range of clinical, hemodynamic, and exercise parameters, performed in a serial fashion over the course of treatment. Approaches to risk assessment in PAH patients include the use of risk variables, scores, and equations that stratify the impact of both modifiable (e.g., 6-min walk distance, functional class, brain natriuretic peptide), and non-modifiable (e.g., age, gender, PAH etiology) risk factors. Such tools allow physicians to better determine prognosis, allocate treatment resources, and enhance the consistency of treatment approaches across providers. Comprehensive and accurate risk prediction is essential to make individualized treatment decisions and optimizing outcomes in PAH.

Hyponatraemia during an emergency medical admission as a marker of illness severity & case complexity

BACKGROUND

Altered sodium balance at time of an emergency medical admission adversely impacts on outcome; whether hyponatraemia is independently associated with outcomes or a surrogate of acute illness severity has been debated.

METHODS

All emergency medical admissions between 2002 and 2017 were studied and a risk score calculated. We compared univarate deciles of admission sodium using a multivariable model, adjusting for risk score.

RESULTS

There were 106,586 admissions in 54,928 patients. Patients with lower sodium at admission were older at 66.7 years (IQR 46.7-79.5) compared with 63.3 years (IQR 42.9-78.2) with a longer length of stay (LOS) of 6.8 days (IQR 3.0-14.7) versus 4.9 days (IQR 1.8-10.9). They had a higher 30-day in-hospital mortality at 6.4% vs 4.4% (p < 0.001). Admission sodium predicted survival - OR 0.89 (95%CI 0.88-0.90). We adjusted the model with a Risk Score that is predictive and exponentially related to 30-day in-hospital mortality. When adjusted for Risk Score, the admission sodium value was less predictive - OR 0.95 (95%CI 0.92-0.97). The cumulative percentages within the lowest five deciles fell from 63.3% between 2002 and 2009 to 48.1% from 2010 to 2017. The slope of the prediction line relating admission sodium to mortality did not change over time but a lower mortality rate was predicted at any given sodium level.

CONCLUSION

Hyponatraemia at the time of an emergency medical admission is predictive and probably a marker of Acuity Illness Severity and Case Complexity. Both the frequency of abnormality in admission sodium and mortality have fallen over time.

Volume Management in Pulmonary Arterial Hypertension Patients: An Expert Pulmonary Hypertension Clinician Perspective

Fluid volume management in patients with pulmonary arterial hypertension (PAH) is essential in preventing right ventricular failure. Volume overload may be caused by disease progression, indiscretion of dietary sodium and fluid intake, or medication side effects, and is a frequent complication in patients with PAH. Healthcare professionals (HCPs) who care for patients with PAH have a key role in monitoring, preventing, and managing volume overload. Volume management techniques in patients with PAH include managing diuretic use and electrolyte imbalances, and monitoring fluid retention that can occur from the use of endothelin receptor antagonists or calcium channel blockers. Healthcare providers can create volume management protocols as well as patient educational materials. Patients should be educated to self-monitor their daily weights, incorporate dietary restrictions, and recognize symptoms associated with volume overload. Tools to help HCPs with volume management in patients with PAH are provided in this article.Funding Actelion Pharmaceuticals US, Inc.

Is hyponatremia associated with mortality in pulmonary arterial hypertension?

Hyponatremia is associated with poor prognosis in left heart failure and liver disease. Its prognostic role in pulmonary arterial hypertension (PAH) is not well defined. We investigated the association between hyponatremia and one-year mortality in two large cohorts of PAH. This study is a secondary analysis evaluating the association between hyponatremia and one-year mortality in patients treated with subcutaneous treprostinil (cohort 1). The results are validated using a PAH registry at a tertiary referral center (cohort 2). Eight-hundred and twenty patients were enrolled in cohort 1 (mean age = 47 ± 14 years) and 791 in cohort 2 (mean age = 55 ± 15 years). Sodium level is negatively correlated with mean right atrial pressure (r = -0.09, P = 0.018; r = -0.089, P = 0.015 in cohorts 1 and 2, respectively). In unadjusted analyses of cohort 1, the sodium level (as a continuous variable) is associated with one-year mortality (hazard ratio = 0.94; P = 0.035). Hyponatremia loses its significance (as a continuous variable and when dichotomized at ≤ 137 mmol/L; P = 0.12) when adjusted for functional class (FC), which is identified as the variable whose presence turns the effect of sodium level into non-significant. Secondary analyses using a cut-off value of < 135 mmol/L showed similar results. These results are validated in cohort 2. Although the sample size for patients with sodium < 130 mmol/L is small (n = 31), severe hyponatremia is associated with higher overall mortality (47% versus 23%; P = 0.01), even when adjusting for age, FC, and baseline 6-min walk distance ( P < 0.001). Although baseline hyponatremia is associated with one-year mortality, it loses its significance when adjusted for FC.

Serum Chloride Levels Track With Survival in Patients With Pulmonary Arterial Hypertension

BACKGROUND

Serum chloride is an important homeostatic biomarker in left heart failure, with significant prognostic implications. The impact of serum chloride in the long-term survival of patients with pulmonary arterial hypertension (PAH) is unknown. We tested whether serum chloride levels are associated with long-term survival in patients with PAH.

METHODS

We included patients with idiopathic or heritable PAH who had a basic metabolic panel performed at the time of their diagnostic right heart catheterization. Laboratory results were recorded both at diagnosis and 6-month follow-up.

RESULTS

We included 277 patients, mean age 51 ± 18 years and 73% women, of whom 254 had a follow-up electrolyte determination at 6 months. Serum chloride was 102.9 ± 3.9 mM/L at diagnosis. A serum chloride ≤ 100 mM/L was noted in 65 (24%) and 53 (21%) patients at diagnosis and 6 months, respectively. Patients with serum chloride ≤ 100 mM/L at 6 months tracked with increase mortality when adjusted by age, sex, pulmonary vascular resistance, diuretics or prostacyclin analogs usage, and serum creatinine and sodium at 6 months (hazard ratio, 1.83; 95% CI, 1.11-3.00). This group of patients was older, with decreased functional capacity, had worse renal function, took more diuretics, had higher pulmonary artery wedge pressure but lower mean pulmonary artery pressure, transpulmonary gradient, and pulmonary vascular resistance.

CONCLUSIONS

Serum chloride at 6 months from the PAH diagnosis is a strong and independent predictor of mortality in patients with idiopathic or heritable PAH, even after adjusting serum sodium, renal function, diuretic, and prostacyclin analog usage.

Hospital and intensive care unit management of decompensated pulmonary hypertension and right ventricular failure

Pulmonary hypertension and concomitant right ventricular failure present a diagnostic and therapeutic challenge in the intensive care unit and have been associated with a high mortality. Significant co-morbidities and hemodynamic instability are often present, and routine critical care unit resuscitation may worsen hemodynamics and limit the chances of survival in patients with an already underlying poor prognosis. Right ventricular failure results from structural or functional processes that limit the right ventricle’s ability to maintain adequate cardiac output. It is commonly seen as the result of left heart failure, acute pulmonary embolism, progression or decompensation of pulmonary hypertension, sepsis, acute lung injury, or in the perioperative setting. Prompt recognition of the underlying cause and institution of treatment with a thorough understanding of the elements necessary to optimize preload, cardiac contractility, enhance systemic arterial perfusion, and reduce right ventricular afterload are of paramount importance. Moreover, the emergence of previously uncommon entities in patients with pulmonary hypertension (pregnancy, sepsis, liver disease, etc.) and the availability of modern devices to provide support pose additional challenges that must be addressed with an in-depth knowledge of this disease.

Risk Assessment in Pulmonary Arterial Hypertension Patients: The Long and Short of it

Pulmonary arterial hypertension (PAH) is a chronic and rapidly progressive disease that is characterized by extensive narrowing of the pulmonary vasculature, leading to increases in pulmonary vascular resistance, subsequent right ventricular dysfunction, and eventual death. There are currently multiple approved drugs—developed as single or combination therapies in the last few years—that have improved outcome and functionality in PAH. However, despite improvement in short-term survival with these new effective therapies, PAH remains an incurable disease with a median survival of 7 years (Figure 1).1 This chronic disease state may be characterized by morbid events such as hospitalizations that herald rapid disease progression and account for a significant disease burden (Figure 2).23 Physician ability to predict PAH disease progression is critical for determining optimal care of patients. Accurate risk assessment allows clinicians to determine the patient's prognosis, identify treatment goals, and monitor disease progression and the patient's response to treatment. Risk assessment for PAH patients should include a range of clinical, hemodynamic, and exercise parameters, performed in a serial fashion over the treatment course. Patient risk stratification can also help physicians better allocate treatment resources in settings where they are scarce. If widely adopted, risk prediction can enhance the consistency of treatment approaches across PAH practitioners and improve the timeliness of referral for lung transplantation. Hence, along with advancing PAH treatment options, comprehensive risk prediction is essential to make individualized treatment decisions in the current treatment era.

Several tools are currently available for assessing risk in PAH (Figure 3). These include the 2015 European Society of Cardiology/European Respiratory Society pulmonary hypertension guidelines' risk variables,4 the French registry equation,5 the National Institutes of Health risk equation,6 or a risk score such as the one derived from the Registry to Evaluate Early And Long-term PAH Disease Management.1 These registries and evaluations of clinical trial sets have provided important insights into the importance of both modifiable (eg, 6-minute walk distance, functional class, brain natriuretic peptide, and nonmodifiable (eg, age, gender, PAH etiology) risk factors that predict survival. The following review explores commonly cited risk factors, both modifiable and nonmodifiable, and their implications for patient outcomes.

Transmural remodeling of right ventricular myocardium in response to pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) imposes substantial pressure overload on the right ventricular free wall (RVFW), leading to myofiber hypertrophy and remodeling of its collagen fiber architecture. The transmural nature of these adaptations and their effects on the macroscopic mechanical behavior of the RVFW remain largely unexplored. In the present work, we extended our constitutive model for RVFW myocardium to investigate the transmural mechanical and structural remodeling post-PAH. Recent murine experimental studies provided us with comprehensive histomorphological and biaxial mechanical data for viable, passive myocardium for normal and post hypertensive cases. Multiple fiber-level remodeling events were found to be localized in the midwall region (40% < depth < 60%): (i) reorientation and alignment of both myo- and collagen fibers towards longitudinal (apex-to-outflow tract) direction, (ii) substantial increase in the rate of the recruitment of collagen fibers with strain, and (iii) a corresponding increase in the mechanical interactions between the collagen and myofibers. These adaptations suggest a denser and more fibrous connective tissue in the midwall region, and led to a substantially stiffer mechanical response along the longitudinal direction in post-PAH tissues. Moreover, using a Laplace-type mechanical equilibrium analysis of the right ventricle to approximate the wall stress state, we estimated that the longitudinal component of stress remained higher in the hypertensive state while the circumferential component approximately maintained homeostasis values. This result was consistent with our observation from the fiber- and tissue-level remodeling that longitudinally oriented collagen fibers, localized in the midwall region, dominated the remodeling process. The findings of this study highlight the need for more integrated cellular-tissue-organ analysis to better understand the remodeling events during PAH and design interventions.

Association between borderline dysnatremia and mortality insight into a new data mining approach

BACKGROUND

Even small variations of serum sodium concentration may be associated with mortality. Our objective was to confirm the impact of borderline dysnatremia for patients admitted to hospital on in-hospital mortality using real life care data from our electronic health record (EHR) and a phenome-wide association analysis (PheWAS).

METHODS

Retrospective observational study based on patient data admitted to Hôpital Européen George Pompidou, between 01/01/2008 and 31/06/2014; including 45,834 patients with serum sodium determinations on admission. We analyzed the association between dysnatremia and in-hospital mortality, using a multivariate logistic regression model to adjust for classical potential confounders. We performed a PheWAS to identify new potential confounders.

RESULTS

Hyponatremia and hypernatremia were recorded for 12.0% and 1.0% of hospital stays, respectively. Adjusted odds ratios (ORa) for severe, moderate and borderline hyponatremia were 3.44 (95% CI, 2.41-4.86), 2.48 (95% CI, 1.96-3.13) and 1.98 (95% CI, 1.73-2.28), respectively. ORa for severe, moderate and borderline hypernatremia were 4.07 (95% CI, 2.92-5.62), 4.42 (95% CI, 2.04-9.20) and 3.72 (95% CI, 1.53-8.45), respectively. Borderline hyponatremia (ORa = 1.57 95% CI, 1.35-1.81) and borderline hypernatremia (ORa = 3.47 95% CI, 2.43-4.90) were still associated with in-hospital mortality after adjustment for classical and new confounding factors identified through the PheWAS analysis.

CONCLUSION

Borderline dysnatremia on admission are independently associated with a higher risk of in-hospital mortality. By using medical data automatically collected in EHR and a new data mining approach, we identified new potential confounding factors that were highly associated with both mortality and dysnatremia.

Acute decompensated pulmonary hypertension

Acute right heart failure in chronic precapillary pulmonary hypertension is characterised by a rapidly progressive syndrome with systemic congestion resulting from impaired right ventricular filling and/or reduced right ventricular flow output. This clinical picture results from an imbalance between the afterload imposed on the right ventricle and its adaptation capacity. Acute decompensated pulmonary hypertension is associated with a very poor prognosis in the short term. Despite its major impact on survival, its optimal management remains very challenging for specialised centres, without specific recommendations. Identification of trigger factors, optimisation of fluid volume and pharmacological support to improve right ventricular function and perfusion pressure are the main therapeutic areas to consider in order to improve clinical condition. At the same time, specific management of pulmonary hypertension according to the aetiology is mandatory to reduce right ventricular afterload. Over the past decade, the development of extracorporeal life support in refractory right heart failure combined with urgent transplantation has probably contributed to a significant improvement in survival for selected patients. However, there remains a considerable need for further research in this field.

Acute decompensated PH is a life-threatening condition requiring specific management in a specialised centrehttp://ow.ly/non530fkhmA

Hyponatraemia and its prognosis in acute heart failure is related to right ventricular dysfunction

OBJECTIVES

Hyponatraemia is a well-known predictor of clinical outcomes in heart failure (HF). However, the mechanism remains poorly understood. Previous reports suggest that hyponatraemia is related to right HF. We sought to evaluate the association between right ventricular (RV) dysfunction and hyponatraemia, and the impact of this relationship on the prognosis of patients with acute heart failure (AHF).

METHODS

This is a nested case-control study of the Korean Acute Heart Failure registry. Among 2935 AHF patients enrolled prospectively and consecutively at four tertiary hospitals in Korea from 2011 to 2014, 116 patients with severe persistent hyponatraemia, defined as serum sodium level <130 mmol/L at admission and <135 mmol/L before discharge, were matched with 232 controls, based on propensity scores for hyponatraemia. RV function was assessed with fractional area change (FAC) by echocardiography.

RESULTS

RV dysfunction (FAC <35%) was more prevalent in patients with severe persistent hyponatraemia than in those without (81.0% vs 33.6%, p<0.001). Hyponatraemia was strongly associated with RV dysfunction (adjusted OR 8.00, 95% CI 4.50 to 14.22, p<0.001), but not with left ventricular dysfunction (adjusted OR 1.21, 95% CI 0.74 to 1.50, p=0.308). RV dysfunction was an independent predictor of all-cause mortality, after adjustment for hyponatraemia (adjusted HR 2.20, 95% CI 1.53 to 3.15, p<0.001), while hyponatraemia was not (adjusted HR 1.33, 95% CI 0.94 to 1.87, p=0.108).

CONCLUSIONS

In patients with AHF, hyponatraemia was more common with RV dysfunction. RV dysfunction, rather than hyponatraemia, was more significantly related with patients' prognosis. Thus, the utility of RV dysfunction instead of hyponatraemia per se should be considered in HF risk models.

TRIAL REGISTRATION NUMBER

Korean Acute Heart Failure registry NCT01389843; Results.

Hyponatremia: A clinical approach

Hyponatremia is the most common electrolyte metabolic abnormality in clinical practice. The unfavorable course of many diseases is associated with hyponatremia. Acute severe hyponatremia is life-threatening because cerebral edema may develop. Less obvious chronic hyponatremia increases the risk of balance problems, falls and fractures, especially in elderly patients. In any occasion, hyponatremia should not be now regarded only as a laboratory phenomenon in critically ill patients, but it necessitates a thorough clinical analysis of each individual case and appropriate therapy. The paper presents approaches to diagnosing and treating hyponatremia in various clinical situations.

Predicting in-hospital death during acute presentation with pulmonary embolism to facilitate early discharge and outpatient management

Background

Pulmonary embolism continues to be a significant cause of death. The aim was to derive and validate a risk prediction model for in-hospital death after acute pulmonary embolism to identify low risk patients suitable for outpatient management.

Methods

A confirmed acute pulmonary embolism database of 1,426 consecutive patients admitted to a tertiary-center (2000–2012) was analyzed, with odd and even years as derivation and validation cohorts respectively. Risk stratification for in-hospital death was performed using multivariable logistic-regression modelling. Models were compared using receiver-operating characteristic-curve and decision curve analyses.

Results

In-hospital mortality was 3.6% in the derivation cohort (n = 693). Adding day-1 sodium and bicarbonate to simplified Pulmonary Embolism Severity Index (sPESI) significantly increased the C-statistic for predicting in-hospital death (0.71 to 0.86, P = 0.001). The validation cohort yielded similar results (n = 733, C-statistic 0.85). The new model was associated with a net reclassification improvement of 0.613, and an integrated discrimination improvement of 0.067. The new model also increased the C-statistic for predicting 30-day mortality compared to sPESI alone (0.74 to 0.83, P = 0.002). Decision curve analysis demonstrated superior clinical benefit with the use of the new model to guide admission for pulmonary embolism, resulting in 43 fewer admissions per 100 presentations based on a risk threshold for admission of 2%.

Conclusions

A risk model incorporating sodium, bicarbonate, and the sPESI provides accurate risk prediction of acute in-hospital mortality after pulmonary embolism. Our novel model identifies patients with pulmonary embolism who are at low risk and who may be suitable for outpatient management.

Assessment of Pulmonary Hypertension in Lung Transplantation Candidates: Correlation of Doppler Echocardiography With Right Heart Catheterization

BACKGROUND

Right heart catheterization (RHC) remains the gold standard to diagnosis of pulmonary hypertension among lung transplantation candidates. Doppler echocardiography (DE) may be as accurate as RHC, without risks of an invasive test. The aim of the study was to assess the feasibility of DE for the measurement of pulmonary artery pressure in lung transplantation candidates and the correlation between pulmonary artery pressures estimated by DE versus measured by RHC.

METHODS

A total of 103 lung transplantation candidates undergoing DE who were scheduled to undergo RHC within 72 hours were analyzed. The performance characteristics of DE were compared with RHC, and correlation analysis was performed to determine the correlation of pulmonary pressures obtained by DE versus measured by RHC.

RESULTS

The prevalence of pulmonary hypertension was 57% in lung transplantation candidates. Of the 103 candidates, evaluation of pulmonary artery systolic pressure (PASP) by DE was possible in 92 (89%). Median PASP by RHC was 45 (12-145) mm Hg and by DE 45 (20-144) mm Hg. There was a positive correlation between PASP estimated by DE and measured by RHC (r = 0.585, P < .0001). Sensitivity, specificity, and positive and negative predictive values of PASP estimation for diagnosis of pulmonary hypertension were 85%, 67%, 87%, and 61%, respectively.

CONCLUSIONS

There is a strong positive correlation between PASP estimated by DE compared with measured by RHC with an acceptable sensitivity and specificity in detecting pulmonary hypertension. Echocardiography can be recommended for measuring pulmonary pressures in lung transplantation candidates.

Kidney dysfunction in patients with pulmonary arterial hypertension

Pulmonary arterial hypertension (PH) and chronic kidney disease (CKD) both profoundly impact patient outcomes, whether as primary disease states or as co-morbid conditions. PH is a common co-morbidity in CKD and vice versa. A growing body of literature describes the epidemiology of PH secondary to chronic kidney disease and end-stage renal disease (ESRD) (WHO group 5 PH). But, there are only limited data on the epidemiology of kidney disease in group 1 PH (pulmonary arterial hypertension [PAH]). The purpose of this review is to summarize the current data on epidemiology and discuss potential disease mechanisms and management implications of kidney dysfunction in PAH. Kidney dysfunction, determined by serum creatinine or estimated glomerular filtration rate, is a frequent co-morbidity in PAH and impaired kidney function is a strong and independent predictor of mortality. Potential mechanisms of PAH affecting the kidneys are increased venous congestion, decreased cardiac output, and neurohormonal activation. On a molecular level, increased TGF-β signaling and increased levels of circulating cytokines could have the potential to worsen kidney function. Nephrotoxicity does not seem to be a common side effect of PAH-targeted therapy. Treatment implications for kidney disease in PAH include glycemic control, lifestyle modification, and potentially Renin-Angiotensin-Aldosterone System (RAAS) blockade.

A novel constitutive model for passive right ventricular myocardium: evidence for myofiber-collagen fiber mechanical coupling

The function of right ventricle (RV) is recognized to play a key role in the development of many cardiopulmonary disorders, such as pulmonary arterial hypertension (PAH). Given the strong link between tissue structure and mechanical behavior, there remains a need for a myocardial constitutive model that accurately accounts for right ventricular myocardium architecture. Moreover, most available myocardial constitutive models approach myocardium at the length scale of mean fiber orientation and do not explicitly account for different fibrous constituents and possible interactions among them. In the present work, we developed a fiber-level constitutive model for the passive mechanical behavior of the right ventricular free wall (RVFW). The model explicitly separates the mechanical contributions of myofiber and collagen fiber ensembles, and accounts for the mechanical interactions between them. To obtain model parameters for the healthy passive RVFW, the model was informed by transmural orientation distribution measurements of myo- and collagen fibers and was fit to the mechanical testing data, where both sets of data were obtained from recent experimental studies on non-contractile, but viable, murine RVFW specimens. Results supported the hypothesis that in the low-strain regime, the behavior of the RVFW is governed by myofiber response alone, which does not demonstrate any coupling between different myofiber ensembles. At higher strains, the collagen fibers and their interactions with myofibers begin to gradually contribute and dominate the behavior as recruitment proceeds. Due to the use of viable myocardial tissue, the contribution of myofibers was significant at all strains with the predicted tensile modulus of [Formula: see text]32 kPa. This was in contrast to earlier reports (Horowitz et al. 1988) where the contribution of myofibers was found to be insignificant. Also, we found that the interaction between myo- and collagen fibers was greatest under equibiaxial strain, with its contribution to the total stress not exceeding 20 %. The present model can be applied to organ-level computational models of right ventricular dysfunction for efficient diagnosis and evaluation of pulmonary hypertension disorder.

The Economic Burden of Hyponatremia: Systematic Review and Meta-Analysis

BACKGROUND

Hyponatremia is the most common electrolyte abnormality observed in clinical practice. Several studies have demonstrated that hyponatremia is associated with an increased length of hospital stay and of hospital resource utilization. To clarify the impact of hyponatremia on the length of hospitalization and costs, we performed a meta-analysis based on published studies that compared hospital length of stay and cost between patients with and without hyponatremia.

METHODS

An extensive Medline, Embase, and Cochrane search was performed to retrieve all studies published up to April 1, 2015 using the following words: "hyponatremia" or "hyponatraemia" AND "hospitalization" or "hospitalisation." A meta-analysis was performed including all studies comparing duration of hospitalization and hospital readmission rate in subjects with and without hyponatremia.

RESULTS

Of 444 retrieved articles, 46 studies satisfied the inclusion criteria, encompassing a total of 3,940,042 patients; among these, 757,763 (19.2%) were hyponatremic. Across all studies, hyponatremia was associated with a significantly longer duration of hospitalization (3.30 [2.90-3.71; 95% CIs] mean days; P < .000). Similar results were obtained when patients with associated morbidities were analyzed separately. Furthermore, hyponatremic patients had a higher risk of readmission after the first hospitalization (odds ratio 1.32 [1.18-1.48; 95% CIs]; P < .000). A meta-regression analysis showed that the hyponatremia-related length of hospital stay was higher in males (Slope = 0.09 [0.05-0.12; 95% CIs]; P = .000 and Intercept = -1.36 [-3.03-0.32; 95% CIs]; P = .11) and in elderly patients (Slope = 0.002 [0.001-0.003; 95% CIs]; P < .000 and Intercept = 0.89 [0.83-0.97; 95% CIs]; P < .001). A negative association between serum [Na(+)] cutoff and duration of hospitalization was detected. No association between duration of hospitalization, serum [Na(+)], and associated morbidities was observed. Finally, when only US studies (n = 8) were considered, hyponatremia was associated with up to around $3000 higher hospital costs/patient when compared with the cost of normonatremic subjects.

CONCLUSIONS

This meta-analysis confirms that hyponatremia is associated with a prolonged hospital length of stay and higher risk of readmission. These observations suggest that hyponatremia may represent one important determinant of the hospitalization costs.

Right atrial emptying fraction non-invasively predicts mortality in pulmonary hypertension

Right-sided heart failure is the most common cause of death in pulmonary hypertension (PH). Echocardiographic measurements of right atrial (RA) size are associated with worse outcome in PH, however the association between RA function and death in PH has not been well-described. 160 PH patients (World Health Organization groups 1-5) underwent cardiac magnetic resonance imaging (cMRI) and right heart catheterization (RHC) within 6 weeks of each other at a tertiary care academic medical center in the United States. We measured cMRI RA maximum and minimum volumes indexed to body surface area and calculated RA emptying fraction (RAEF). We evaluated the relationship between RAEF and clinical variables with death using Cox proportional hazard models. 57 deaths occurred during a median follow-up of 3.5 years (36 % died overall, 10 % per year). RAEF was directly correlated in univariate analyses with right ventricular (RV) ejection fraction, left ventricular (LV) ejection fraction, LV size, cardiac index, absence of tricuspid and pulmonic regurgitation, absence of pericardial effusion, estimated glomerular filtration rate, 6-minute walk distance, and pulmonary arterial oxygen saturation, whereas it was inversely correlated with death, BNP, heart rate, mean RA pressure, mean PA pressure, pulmonary and systemic vascular resistance, RV size, and RA size. Using multivariate analyses, RAEF had a robust inverse association with death after adjusting for measured risk factors (HR per 5 % change in RAEF: 0.83 [95 % CI 0.73-0.94], p = 0.003). In PH patients, decreased RAEF by cMRI is independently associated with worse survival after adjustment for other risk factors.

Hyponatremia and 30 days mortality of patients with acute pulmonary embolism

Background:

Hyponatremia has poor outcomes in other cardiopulmonary disorders, but its predictive value in predicting mortality of patients with acute pulmonary embolism is unknown. So, we evaluate the mortality of inpatients diagnosed with pulmonary embolism (PE) who had hyponatremia at the time of admission.

Materials and Methods:

By conducting a cohort study in patients with acute pulmonary embolism admitted in Al-Zahra Hospital during the 24 months of the date of March 2012 to March 2014. We evaluated 224 patients admitted with a primary diagnosis of PE. We used logistic regression analysis to evaluate the independent relation among serum sodium levels at the time of presentation and 30 days mortality, with severity of illness and other patient risk factors were adjusted.

Results:

109 patients (48.7%) had normal sodium level (serum level >137 mmol/L). 115 patients had sodium level bellow 137 mmol/L. Of these, 56 (25%) had a sodium level 135-137 mmol/L and 59 (26.3%) had a sodium level <135 mmol/L. Patients with a serum sodium of >137, 135-137, and <135 mmol/L had a cumulative 30-day mortality of 14%, 21%, and 42% (P < 0.0001), respectively. The mortality of patients with lower serum sodium was significantly increased. When the pulmonary embolism severity index and also its simplified form were replaced in the model and while some confounding variables such patients with a history of cancer, chronic pulmonary disease, heart failure, and chronic renal failure were excluded from statistics, the findings still remained similar.

Conclusion:

Among patients presenting with PE, hyponatremia is common and is an independent risk factor that increasing short-term mortality. This result could be encountered as a variable in determining of PE severity and mortality.

Existing drugs and agents under investigation for pulmonary arterial hypertension

Pulmonary arterial hypertension is a progressive and debilitating disorder with an associated high morbidity and mortality rate. Significant advances in our understanding of the epidemiology, pathogenesis, and pathophysiology of pulmonary hypertension have occurred over the past several decades. This has allowed the development of new therapeutic options in this disease. Today, our selection of therapeutic modalities is broader, including calcium channel blockers, prostanoids, endothelin receptor antagonists, phosphodiesterase inhibitors, and soluble guanylate cyclase stimulators, but the disease remains fatal. This underscores the need for a continued search for novel therapies. Several potential pharmacologic agents for the treatment of pulmonary arterial hypertension are under clinical development and some promising results with these treatments have been reported. These agents include rho-kinase inhibitors, long-acting nonprostanoid prostacyclin receptor agonists, tyrosine protein kinase inhibitors, endothelial nitric oxide synthase couplers, synthetically produced vasoactive intestinal peptide, antagonists of the 5-HT2 receptors, and others. This article will review several of these promising new therapies and will discuss the current evidence regarding their potential benefit in pulmonary arterial hypertension.

Associations of circulating natriuretic peptides with haemodynamics in precapillary pulmonary hypertension

BACKGROUND

While N-terminal B-type natriuretic peptide (NT-proBNP) has been examined extensively in pulmonary hypertension (PH), limited data exists on the subtype A, C and D. The aim of this prospective pilot study was a head-to-head comparison of NPs in respect to haemodynamic parameters and the influence of renal function.

METHODS

Plasma samples were drawn during routine right heart catheterization in 62 patients with precapillary PH and 20 control patients. MR-proANP measurements were performed on the automated Kryptor platform, NT-proBNP by CLIA, NT-proCNP and DNP levels by ELISA. Results are expressed as median [range] and tested non-parametrically. Non-parametric locally linear multiple regression was performed to determine the influence of renal function on NP levels. P-values <0.05 were considered significant.

RESULTS

Patients with PH had significantly higher MR-proANP and NT-proBNP levels. NT-proCNP showed a trend to higher levels, while DNP did not differ from control subjects. Both MR-proANP and NT-proBNP were associated with cardiac index (CI), right atrial pressure (RAP), mean pulmonary artery pressure (PAPm) and pulmonary vascular resistance index (PVRI). NT-proCNP was associated with RAP, while DNP showed no associations with haemodynamic variables. Associations of haemodynamic parameters with NPs were weakened in patients with in elevated serum creatinine and showed increased regression slopes.

CONCLUSION

MR-proANP demonstrated equivalent associations with haemodynamics compared to NT-proBNP, but both markers depend on intact renal function. NT-proCNP was correlated with RAP and renal function, while DNP showed no associations. Larger studies should evaluate MR-proANP as candidate prognostic biomarker in PH.