Presence of Kidney Disease as an Outcome Predictor in Patients with Pulmonary Arterial Hypertension

Sex differences in pulmonary arterial hypertension: Insights from the FOCUS-PAH registry

BACKGROUND

Despite the higher incidence of pulmonary arterial hypertension (PAH) in women, sex differences in terms of clinical presentation and prognosis are still uncertain. We assess the impact of sex in patients with PAH.

METHODS

Sex differences were evaluated in the multicenter FOCUS-PAH registry, that included patients diagnosed with PAH at 7 tertiary care centers between 2001 and 2022. Patients' characteristics and outcomes were compared in men vs. women, and factors independently associated with long-term outcomes were assessed. The primary endpoint was overall survival.

RESULTS

Among 410 included patients, 273 (66.6 %) were women and 137 (33.4 %) were men. Despite similar age, men had more cardio-renal-metabolic comorbidities and history of HIV infection, whereas women had more connective tissue disorders and scleroderma, and worse functional capacity. Dual therapy was more commonly prescribed in women (39.9 % vs. 27.0 %). At multivariable Cox regression analysis, female sex was independently associated with a lower risk of all-cause mortality (adjusted hazard ratio 0.60, 95 % confidence interval 0.38-0.95, p = 0.031). Age, European Society of Cardiology (ESC) / European Respiratory Society (ERS) risk score, glomerular filtration rate and scleroderma were independently associated with long-term mortality in women, whereas only age and ESC/ERS risk score independently predicted this endpoint in men.

CONCLUSIONS

In this real-world registry, women represented 2 out of 3 patients with PAH and female sex was independently associated with a lower risk of mortality. There were differences in the variables associated with long-term mortality between sexes, suggesting that individualized approach to risk stratification should also include sex.

ROS-Activated TRPM2 Channel: Calcium Homeostasis in Cardiovascular/renal System and Speculation in Cardiorenal Syndrome

The transient receptor potential melastatin 2 (TRPM2) channel is a nonselective calcium channel that is sensitive to oxidative stress (OS), and is widely expressed in multiple organs, such as the heart, kidney, and brain, which is inextricably related to calcium dyshomeostasis and downstream pathological events. Due to the increasing global burden of kidney or cardiovascular diseases (CVDs), safe and efficient drugs specific to novel targets are imperatively needed. Notably, investigation of the possibility to regard the TRPM2 channel as a new therapeutic target in ROS-related CVDs or renal diseases is urgently required because the roles of the TRPM2 channel in heart or kidney diseases have not received enough attention and thus have not been fully elaborated. Therefore, we aimed to review the involvement of the TRPM2 channel in cardiovascular disorders related to kidney or typical renal diseases and attempted to speculate about TRPM2-mediated mechanisms of cardiorenal syndrome (CRS) to provide representative perspectives for future research about novel and effective therapeutic strategies.

Cardiorenal Syndrome in Right Heart Failure Due to Pulmonary Arterial Hypertension-The Right Ventricle as a Therapeutic Target to Improve Renal Function

Cardiorenal syndrome (CRS) due to right ventricular (RV) failure is a disease entity emerging as a key indicator of morbidity and mortality. The multifactorial aspects of CRS and the left-right ventricular interdependence complicate the link between RV failure and renal function. RV failure has a direct pathophysiological link to renal dysfunction by leading to systemic venous congestion in certain circumstances and low cardiac output in other situations, both leading to impaired renal perfusion. Indeed, renal dysfunction is known to be an independent predictor of mortality in patients with pulmonary arterial hypertension (PAH) and RV failure. Thus, it is important to further understand the interaction between the RV and renal function. RV adaptation is critical to long-term survival in patients with PAH. The RV is also known for its remarkable capacity to recover once the aggravating factor is addressed or mitigated. However, less is known about the renal potential for recovery following the resolution of chronic RV failure. In this review, we provide an overview of the intricate relationship between RV dysfunction and the subsequent development of CRS, with a particular emphasis on PAH. Additionally, we summarize potential RV-targeted therapies and their potential beneficial impact on renal function.

Tricuspid Annular Plane Systolic Excursion/Systolic Pulmonary Artery Pressure Ratio and Cardiorenal Syndrome Type 2 in the Systemic Sclerosis EUSTAR Cohort

OBJECTIVE

The aim of the study was to evaluate the association between the tricuspid annular plane systolic excursion (TAPSE)/systolic pulmonary artery pressure (sPAP) ratio and estimated glomerular filtration rate (eGFR) and their association with mortality in the European Scleroderma Trials and Research (EUSTAR) cohort.

METHODS

Patients with systemic sclerosis (SSc) from the EUSTAR database with TAPSE, sPAP, and parameters required to calculate eGFR were included. Logistic regression and Cox regression analysis were performed to evaluate TAPSE/sPAP as a risk factor for chronic kidney disease (CKD) and overall survival.

RESULTS

A total of 2,370 patients with SSc were included; 284 (12%) patients had CKD stage 3a-5. TAPSE/sPAP (odds ratio [OR] 0.479; 95% CI 0.310-0.743; P < 0.001), arterial hypertension (OR 3.118; 95% CI 2.173-4.475; P < 0.001), diastolic dysfunction (OR 1.670; 95% CI 1.148-2.428; P < 0.01), and N-terminal pro-B-type natriuretic peptide (OR 1.165; 95% CI 1.041-1.304; P < 0.01) were associated with CKD stage 3a-5. TAPSE/sPAP ≤0.32 mm/mm Hg (hazard ratio [HR] 3.589; 95% CI 2.236-5.761; P < 0.001), eGFR <60 mL/min per 1.73 m2 (HR 2.818; 95% CI 1.777-4.468; P < 0.001), and age (HR 1.782; 95% CI 1.348-2.356; P < 0.001) were the most significant predictive factors for all-cause mortality. A total of 276 patients with SSc had pulmonary hypertension (PH) confirmed by right-sided heart catheterization, with 69 (25%) having CKD stage 3a-5. No difference was found in eGFR between patients with PH with reduced or normal cardiac index.

CONCLUSION

Reduced TAPSE/sPAP ratio is independently associated with CKD. TAPSE/sPAP ratio ≤0.32 mm/mm Hg and eGFR <60 mL/min per 1.73 m2 are prognostic factors for all-cause mortality. In patients with SSc with PH, eGFR is independent by reduced cardiac output.

Pulmonary hypertension and chronic kidney disease: prevalence, pathophysiology and outcomes

Pulmonary hypertension (PH) is common in patients with chronic kidney disease (CKD) or kidney failure, with an estimated prevalence of up to 78% in those referred for right-heart catheterization. PH is independently associated with adverse outcomes in CKD, raising the possibility that early detection and appropriate management of PH might improve outcomes in at-risk patients. Among patients with PH, the prevalence of CKD stages 3 and 4 is estimated to be as high as 36%, and CKD is also independently associated with adverse outcomes. However, the complex, heterogenous pathophysiology and clinical profile of CKD-PH requires further characterization. CKD is often associated with elevated left ventricular filling pressure and volume overload, which presumably leads to pulmonary vascular stiffening and post-capillary PH. By contrast, a distinct subgroup of patients at high risk is characterized by elevated pulmonary vascular resistance and right ventricular dysfunction in the absence of pulmonary venous hypertension, which may represent a right-sided cardiorenal syndrome defined in principle by hypervolaemia, salt avidity, low cardiac output and normal left ventricular function. Current understanding of CKD-PH is limited, despite its potentially important ramifications for clinical decision making. In particular, whether PH should be considered when determining the suitability and timing of kidney replacement therapy or kidney transplantation is unclear. More research is urgently needed to address these knowledge gaps and improve the outcomes of patients with or at risk of CKD-PH.

Transplantation, bridging, and support technologies in pulmonary hypertension

Despite the progress made in medical therapies for treating pulmonary hypertension (PH), a subset of patients remain susceptible to developing a maladaptive right ventricular phenotype. The effective management of end-stage PH presents substantial challenges, necessitating a multidisciplinary approach and early identification of patients prone to acute decompensation. Identifying potential transplant candidates and assessing the feasibility of such a procedure are pivotal tasks that should be undertaken early in the treatment algorithm. Inclusion on the transplant list is contingent upon a comprehensive risk assessment, also considering the specific type of PH and various factors affecting waiting times, all of which should inform the decision-making process. While bilateral lung transplantation is the preferred option, it demands expert intra- and post-operative management to mitigate the heightened risks of pulmonary oedema and primary graft dysfunction in PH patients. Despite the availability of risk assessment tools, the occurrence of acute PH decompensation episodes can be unpredictable, potentially leading to refractory right ventricular failure even with optimal medical intervention, necessitating the use of rescue therapies. Advancements in right ventricular assist techniques and adjustments to graft allocation protocols for the most critically ill patients have significantly enhanced the survival in intensive care, affording the opportunity to endure while awaiting an urgent transplant. Given the breadth of therapeutic options available, specialised centres capable of delivering comprehensive care have become indispensable for optimising patient outcomes. These centres are instrumental in providing holistic support and management tailored to the complex needs of PH patients, ultimately enhancing their chances of a successful transplant and improved long-term prognosis.

Prognostic implication of glomerular filtration rates in patients with chronic thromboembolic pulmonary hypertension who have undergone balloon pulmonary angioplasty

Chronic thromboembolic pulmonary hypertension (CTEPH) plays a key role in the deterioration of lung hemodynamics and contributes to secondary dysfunction of the right heart, which is consistently accompanied by systemic malperfusion and a reduced glomerular filtration rate (GFR). The prognosis of CTEPH is markedly influenced by renal function. The aim of the present study was to evaluate the prognostic value of GFR in patients with CTEPH who have undergone balloon pulmonary angioplasty (BPA). From December 2012 to September 2020, a total of 47 patients diagnosed with CTEPH who received BPA were retrospectively studied. Patients were categorized according to their renal function on admission into two groups: GFR >53 and ≤53. Biological, clinical and demographic data of the patients were collected. Data for the two groups in hospital and during follow-up were systematically analyzed and compared. All-cause mortality, death from right heart failure (RHF) and rehospitalization associated with RHF were considered major adverse events (MAEs). The results revealed that the 6-min walk distance, N-terminal pro-B type natriuretic peptide (NT-proBNP), Troponin I and right ventricle diameter were significantly lower, and tricuspid annular plane systolic excursion was significantly higher in the GFR >53 group compared with the GFR ≤53 group at final follow-up. In addition, GFR levels were significantly correlated with NT-proBNP at baseline and final follow-up. Furthermore, based on a multivariate analysis, it was determined that the decreased GFR was an independent predictor of MAEs during follow-up. Therefore, it may be concluded that in addition to being associated with right ventricular function, decreased GFR is also a prognostic marker in CTEPH treated with BPA.

Diagnostic Value of Serum Galectin-3 Binding Protein Level in Patients with Pulmonary Arterial Hypertension

BACKGROUND

Pulmonary arterial hypertension (PAH) still lacks effective biomarkers to assist in its diagnosis and prognosis. Galectin-3 binding protein (Gal-3BP) plays a role in immune and inflammatory diseases.

OBJECTIVE

This study aimed to evaluate Gal-3BP as a prognostic and predictive factor in patients with PAH.

METHODS

From January 2017 to December 2019, we enrolled 167 consecutive PAH patients and 58 healthy controls. Right heart catheterization (RHC) was used to diagnose PAH. Serum Gal-3BP levels were measured by high-sensitivity human enzyme-linked immunosorbent assay (ELISA).

RESULTS

Serum Gal-3BP levels in the PAH group were significantly higher compared with the control group (4.87±2.09 vs 2.22±0.86 μg/mL, p<0.001). Gal-3BP level was correlated with several hemodynamic parameters obtained from RHC (p<0.001). Multivariate linear regression analysis showed that Gal-3BP was a risk factor for PAH (odds ratio (OR)=2.947, 95% CI: 1.821-4.767, p<0.001). The optimal cut-off value of serum Gal-3BP level for predicting PAH was 2.89 μg/mL (area under the curve (AUC)=0.860, 95 % CI: 0.811-0.910, p<0.001). Kaplan-Meier analysis showed that Gal-3BP levels above the median (4.87 μg/mL) were associated with an increased risk of death in patients with PAH (hazard ratio (HR)=8.868, 95 % CI: 3.631-21.65, p<0.0001). Cox multivariate risk regression analysis showed that Gal-3BP was a risk factor for death in PAH patients (HR=2.779, 95 % CI: 1.823-4.237, p<0.001).

CONCLUSION

Serum Gal-3BP levels were increased in patients with PAH, and levels of Gal-3BP were associated with the severity of PAH. Gal-3BP might have predictive value for the diagnosis and prognosis of PAH.

The potential of cystatin C as a predictive biomarker in pulmonary hypertension

BACKGROUND

Cystatin C is a novel biomarker to identify renal dysfunction and cardiovascular risk.

OBJECTIVE

The aim of this study was to investigate the role of cystatin C in non-invasive risk prediction in a large cohort of patients with pre-capillary pulmonary hypertension (PH).

METHOD

We retrospectively analyzed pre-capillary PH patients with available cystatin C and hemodynamic data derived from right heart catheterization.

RESULTS

A total of 398 consecutive patients with confirmed pre-capillary PH were recruited from Fuwai Hospital between November 2020 and November 2021. Over a median duration of 282 days, 72 (18.1%) of these patients experienced clinical worsening. Cystatin C levels significantly correlated with cardiac index (r = -0.286, P < 0.001), mixed venous oxygen saturation (r = -0.216, P < 0.001), and tricuspid annular plane systolic excursion (r = -0.236, P < 0.001), and high cystatin C levels independently predicted a poor prognosis after adjusting potential confounders in different models (all P < 0.05). A three-group non-invasive risk model was constructed based on the combined assessment of the cystatin C and WHO-FC using dichotomous cut-off value. Those patients with higher cystatin C (≥ 1.0 mg/L) and a worse WHO-FC experienced the highest risk of endpoint occurrence. The predictive capacity of this model was comparable to that of an existing invasive risk stratification model (area under curve: 0.657 vs 0.643, P = 0.619).

CONCLUSIONS

Cystatin C levels were associated with disease severity and prognosis in patients with pre-capillary PH. A combination of high cystatin C and advanced WHO-FC identifies patients at particularly high risk of clinical deterioration.

Pressure Overload and Right Ventricular Failure: From Pathophysiology to Treatment

Right ventricular failure (RVF) is often caused by increased afterload and disrupted coupling between the right ventricle (RV) and the pulmonary arteries (PAs). After a phase of adaptive hypertrophy, pressure-overloaded RVs evolve towards maladaptive hypertrophy and finally ventricular dilatation, with reduced stroke volume and systemic congestion. In this article, we review the concept of RV-PA coupling, which depicts the interaction between RV contractility and afterload, as well as the invasive and non-invasive techniques for its assessment. The current principles of RVF management based on pathophysiology and underlying etiology are subsequently discussed. Treatment strategies remain a challenge and range from fluid management and afterload reduction in moderate RVF to vasopressor therapy, inotropic support and, occasionally, mechanical circulatory support in severe RVF.

Right Heart Function in Cardiorenal Syndrome

PURPOSE OF REVIEW

Since CRS is critically dependent on right heart function and involved in interorgan crosstalk, assessment and monitoring of both right heart and kidney function are of utmost importance for clinical outcomes. This systematic review aims to comprehensively report on novel diagnostic and therapeutic paradigms that are gaining importance for the clinical management of the growing heart failure population suffering from CRS.

RECENT FINDINGS

Cardiorenal syndrome (CRS) in patients with heart failure is associated with poor outcome. Although systemic venous congestion and elevated central venous pressure have been recognized as main contributors to CRS, they are often neglected in clinical practice. The delicate hemodynamic balance in CRS is particularly determined by the respective status of the right heart. The consideration of hemodynamic and CRS profiles is advantageous in tailoring treatment for better preservation of renal function. Assessment and monitoring of right heart and renal function by known and emerging tools like renal Doppler ultrasonography or new biomarkers may have direct clinical implications.

Renal Replacement Therapy in Patients With Acute Decompensated Pulmonary Hypertension Admitted to the Intensive Care Unit

Background: Pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension (PH) are characterized hemodynamically by pre-capillary PH. Acute worsening of systemic congestion and/or reduced right ventricular flow output in patients with pre-capillary PH characterizes an episode of acute decompensated PH. Acute kidney injury (AKI) is a common complication in this population and those patients frequently use renal replacement therapy (RRT). Predictors and timing for RRT in acute decompensated PH are unknown and mortality of patients who require this therapy is high. We hypothesize that AKI and hypervolemia are associated with use of RRT during episodes of acute decompensated PH in patients with pre-capillary PH requiring intensive care unit (ICU) admission.

Aim: Explore variables associated with RRT use, develop a decision tree model to predict use of RRT in acute decompensated PH and analyze ICU, in-hospital and 90-days mortality in this population.

Materials and methods: Multicenter retrospective cohort study including patients with pulmonary arterial hypertension and chronic thromboembolic PH with unplanned admission in the ICU for acute decompensated PH. Acute decompensated PH was defined by acute right ventricular failure leading to low cardiac output and elevated right ventricle filling pressures. We employed two multivariable logistic regression models using directed acyclic graphs to identify confounders. Unadjusted and adjusted odds ratios and 95% confidence intervals were used to measure the association between variables and RRT use.

Results: Some 73 patients were included, 16.4% (n=12) of patients required RRT during ICU stay. In the univariate analysis, right atrial pressure (RAP) on last right heart catheterization, and creatinine upon ICU admission were associated with use of RRT and were included in the multivariable model and in the decision tree model. The decision tree model based on RAP and creatinine showed sensitivity of 58.3% and specificity of 100% with area under the receiver operating characteristic curve of 0.81 for predicting RRT use in the ICU. In-hospital mortality and 90-days mortality of patients who used RRT were higher than in patients that did not use RRT (75.0% vs. 34.4%, p < 0.01 and 83.3% vs. 42.6%, p = 0.01, respectively).

Conclusion: The decision tree model based on creatinine upon admission and RAP, which is a surrogate of hypervolemia, can identify patients at risk for RRT. Increased ICU, in-hospital, and 90-days mortality were observed in patients with acute decompensated PH who used RRT in the ICU. 

Development of an Electronic Frailty Index for Predicting Mortality and Complications Analysis in Pulmonary Hypertension Using Random Survival Forest Model

BACKGROUND

The long-term prognosis of the cardio-metabolic and renal complications, in addition to mortality in patients with newly diagnosed pulmonary hypertension, are unclear. This study aims to develop a scalable predictive model in the form of an electronic frailty index (eFI) to predict different adverse outcomes.

METHODS

This was a population-based cohort study of patients diagnosed with pulmonary hypertension between January 1st, 2000 and December 31st, 2017, in Hong Kong public hospitals. The primary outcomes were mortality, cardiovascular complications, renal diseases, and diabetes mellitus. The univariable and multivariable Cox regression analyses were applied to identify the significant risk factors, which were fed into the non-parametric random survival forest (RSF) model to develop an eFI.

RESULTS

A total of 2,560 patients with a mean age of 63.4 years old (interquartile range: 38.0-79.0) were included. Over a follow-up, 1,347 died and 1,878, 437, and 684 patients developed cardiovascular complications, diabetes mellitus, and renal disease, respectively. The RSF-model-identified age, average readmission, anti-hypertensive drugs, cumulative length of stay, and total bilirubin were among the most important risk factors for predicting mortality. Pair-wise interactions of factors including diagnosis age, average readmission interval, and cumulative hospital stay were also crucial for the mortality prediction. Patients who developed all-cause mortality had higher values of the eFI compared to those who survived (P < 0.0001). An eFI ≥ 9.5 was associated with increased risks of mortality [hazard ratio (HR): 1.90; 95% confidence interval [CI]: 1.70-2.12; P < 0.0001]. The cumulative hazards were higher among patients who were 65 years old or above with eFI ≥ 9.5. Using the same cut-off point, the eFI predicted a long-term mortality over 10 years (HR: 1.71; 95% CI: 1.53-1.90; P < 0.0001). Compared to the multivariable Cox regression, the precision, recall, area under the curve (AUC), and C-index were significantly higher for RSF in the prediction of outcomes.

CONCLUSION

The RSF models identified the novel risk factors and interactions for the development of complications and mortality. The eFI constructed by RSF accurately predicts the complications and mortality of patients with pulmonary hypertension, especially among the elderly.

Retinal vessel changes in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is classically considered an isolated small vessel vasculopathy of the lungs with peripheral pulmonary vascular obliteration. Systemic manifestations of PAH are increasingly acknowledged, but data remain limited. We hypothesized that retinal vascular changes occur in PAH. PAH subjects underwent retinal fluorescein angiography (FA) and routine disease severity measures were collected from the medical record. FA studies were analyzed using VESsel GENerational Analysis (VESGEN), a noninvasive, user‐interactive computer software that assigns branching generation to large and small vessels. FAs from controls (n = 8) and PAH subjects (n = 9) were compared. The tortuosity of retinal arteries was higher in PAH subjects compared to unmatched controls (1.17, 95% confidence interval: [1.14, 1.20] in PAH vs. 1.13, 95% CI: [1.12, 1.14] in controls, p = 0.01). Venous tortuosity was higher and more variable in PAH (1.17, 95% CI: [1.14, 1.20]) compared to controls (1.13, 95% CI: [1.12, 1.15]), p = 0.02. PAH subjects without connective tissue disease had the highest degree of retinal tortuosity relative to controls (arterial, p = 0.01; venous, p = 0.03). Younger PAH subjects had greater retinal arterial tortuosity, which attenuated with age and was not observed in controls. Retinal vascular parameters correlated with some clinical measures of disease in PAH subjects. In conclusion, PAH subjects exhibit higher retinal vascular tortuosity. Retinal vascular changes may track with pulmonary vascular disease progression. Use of FA and VESGEN may facilitate early, noninvasive detection of PAH.

miR-1226-3p Promotes eNOS Expression of Pulmonary Arterial Endothelial Cells to Mitigate Hypertension in Rats via Targeting Profilin-1

In pulmonary arterial hypertension (PAH), microRNAs (miRNAs) are related with dysfunction of pulmonary arterial endothelial cells. miR-1226-3p was found to be downregulated in the serum of PAH patients, while few studies have illustrated the regulation mechanism of miR-1226-3p on PAH. In this study, we aimed to systematically investigate the role of miR-1226-3p in PAH. Sprague-Dawley (SD) rats were treated with monocrotaline (MCT) to establish the PAH models. The right ventricular systolic pressure (RVSP), ratio of the right ventricle to the left ventricle with septum (RV/(LV+S) ratio), and nitric oxide (NO) content were used to reflect the symptom of the rats. The rat models were used to observe the regulation mechanism of miR-1226-3p on PAH, and dual-luciferase reporter assay was used to verify the binding effect of miR-1226-3p to Pfn1. Besides, the qRT-PCR and western blot were used to measure the expression levels of miR-1226-3p and some keys proteins such as eNOS and Pfn1, respectively. The results showed that the PAH models were established successfully. The RVSP levels and the RV/(LV+S) ratio of the PAH rats were higher than those indexes in normal rats, while the NO content showed the opposite trends. Besides, the decreased miR-1226-3p and eNOS were, respectively, found in the PAH rats and rPAECs, and overexpressed miR-1226-3p could reverse the disadvantages of the PAH rats including increased RVSP, high RV/(LV+S) ratio, and decreased NO content. Furthermore, miR-1226-3p could directly target the 3'-UTR of Profilin-1 (Pfn1). Overexpressed Pfn1 led to decreased eNOS, while miR-1226-3p could partly inhibit the expression of Pfn1 and increase the expression level of eNOS in rPAECs. In summary, this study suggests miR-1226-3p as a protector to increase eNOS, improve NO content in rPAECs of the PAH rats via targeting Pfn, and finally protect the rats from the injury induced by PAH.

Pulmonale Hypertonie und Rechtsherzinsuffizienz

Pulmonale Hypertonie (PH) beschreibt einen hämodynamischen Zustand, der durch eine Druckerhöhung im kleinen Kreislauf charakterisiert ist und der insbesondere bei älteren Patienten häufig zu beobachten ist. In Abhängigkeit der Ätiologie differenziert die klinische Klassifikation der pulmonalen Hypertonie 5 Hauptgruppen. Unabhängig von der zugrunde liegenden Ursache führt eine PH zu einer chronischen Rechtsherzbelastung und Rechtsherzinsuffizienz. Aktuelle Studien zeigen, dass bereits eine moderate Erhöhung des pulmonalarteriellen Druckes sowie des pulmonalvaskulären Widerstands prognoserelevant sind. Im Einzelfall ist die konsequente differenzialdiagnostische Abklärung einer PH essenziell, da sich die Behandlungsoptionen je nach zugrunde liegender Ursache grundlegend unterscheiden.

Hemodynamic Response to Treatment and Outcomes in Pulmonary Hypertension Associated With Interstitial Lung Disease Versus Pulmonary Arterial Hypertension in Systemic Sclerosis: Data From a Study Identifying Prognostic Factors in Pulmonary Hypertension Associated With Interstitial Lung Disease

OBJECTIVE

Patients with systemic sclerosis and both pulmonary hypertension and interstitial lung disease (SSc-PH-ILD) generally carry a worse prognosis than patients with SSc and pulmonary arterial hypertension (SSc-PAH) without ILD. There is no evidence of the efficacy of PAH therapies in SSc-PH-ILD. We undertook this study to compare survival of and response to treatment in patients with SSc-PH-ILD and those with SSc-PAH.

METHODS

We analyzed 128 patients (66 with SSc-PH-ILD and 62 with SSc-PAH) from 15 centers, in whom PH was diagnosed by right-sided heart catheterization; they were prospectively included in the PH registry. All patients received PAH-specific therapy. Computed tomography of the chest was used to confirm or exclude ILD.

RESULTS

At baseline, patients with SSc-PH-ILD had less severe hemodynamic impairment than those with SSc-PAH (pulmonary vascular resistance 5.7 Wood units versus 8.7 Wood units; P = 0.0005) and lower diffusing capacity for carbon monoxide (median 25% [interquartile range (IQR) 18%, 35%] versus 40% [IQR 31%, 51%]; P = 0.0005). Additionally, patients with SSc-PH-ILD had increased mortality (8.1% at 1 year, 21.2% at 2 years, and 41.5% at 3 years) compared to those with SSc-PAH (4.1%, 8.7%, and 21.4%, respectively; P = 0.04). Upon treatment with PAH-targeted therapy, no improvement in the 6-minute walk distance was observed in either group. Improvement in the World Health Organization functional class was observed less frequently in patients with SSc-ILD-PH compared to those with SSc-PAH (13.6% versus 33.3%; P = 0.02). Hemodynamics improved similarly in both groups.

CONCLUSION

ILD confers a worse prognosis to SSc-PH. Response to PAH-specific therapy is clinically poor in SSc-PH-ILD but was not found to be hemodynamically different from the response observed in SSc-PAH.

Renal protective effect of sodium ferulate on pulmonary hypertension patients undergoing computed tomography pulmonary angiography

This study aimed to explore the correlation of sodium ferulate and the renal protective effect on computed tomography pulmonary angiography in patients suffering from pulmonary hypertension. This prospective study enrolled 92 consecutive patients with pulmonary hypertension diagnosed by echocardiography, and all included patients underwent computed tomography pulmonary angiography after admission. The participants were randomized, divided into sodium ferulate group (n = 49) and control group (n = 43), of which patients in the sodium ferulate group received intravenous sodium ferulate 3.0 g per day from 12 h before computed tomography pulmonary angiography examination to 72 h after that, and patients in the control group were provided with routine treatment. Renal function was assessed by measuring serum creatinine, estimated glomerular filtration rate, Cystatin-C as well as 24 h, 48 h, and 72 h after computed tomography pulmonary angiography, followed by the calculation of the incidence of contrast-induced nephropathy for contrast-induced nephropathy and non-contrast-induced nephropathy grouping. Besides, renal resistive index was determined via Doppler ultrasound examination before, after 1 h and 24 h after computed tomography pulmonary angiography. There were no significant differences between the two groups in serum creatinine at baseline and 24 h after computed tomography pulmonary angiography (P > 0.05, respectively), but at 48 h and 72 h, it was lower in the sodium ferulate group (P < 0.05). There were no significant differences of estimated glomerular filtration rate between the two groups (P > 0.05). The level of Cystatin-C at 48 h and 72 h after computed tomography pulmonary angiography was lower than in the sodium ferulate group (P < 0.05). Contrast-induced nephropathy was identified in nine patients (9.78%). Sodium ferulate was associated with a decline in the incidence of contrast-induced nephropathy (4.08 vs. 16.28 %, P < 0.05). Compared to patients with contrast-induced nephropathy, lower renal resistive index were observed at 1 h and 24 h after computed tomography pulmonary angiography in patients without contrast-induced nephropathy (P < 0.05). Infusion of sodium ferulate before and after computed tomography pulmonary angiography was associated with a decline in incidence of contrast-induced nephropathy.

Mid-regional pro-atrial natriuretic peptide and copeptin as indicators of disease severity and therapy response in CTEPH

BACKGROUND

Chronic thromboembolic pulmonary hypertension (CTEPH) leads to right heart failure. Pulmonary endarterectomy (PEA) or balloon pulmonary angioplasty (BPA) restore pulmonary haemodynamics and allow cardiac recovery. This study examined the relationship of copeptin and mid-regional pro-atrial natriuretic peptide (MR-proANP) levels to disease severity and therapy response.

METHODS

This observational cohort study included 125 patients (55 PEA/70 BPA) who underwent treatment and completed a 6-/12-month follow-up. Biomarkers, measured at baseline, prior to every BPA and at follow-up, were compared to 1) severe disease at baseline (right atrial pressure (RAP) ≥8 mmHg and cardiac index ≤2.4 L·min-1·m-2) and 2) optimal therapy response (no persistent pulmonary hypertension combined with a normalised RAP (mean PAP ≤25 mmHg, pulmonary vascular resistance (PVR) ≤3 WU and RAP ≤6 mmHg) or a reduction in mean PAP ≥25%, PVR ≥35% and RAP ≥25%).

RESULTS

Severely diseased patients had higher levels of MR-proANP (320 (246-527) pmol·L-1 versus 133 (82-215) pmol·L-1; p=0.001) and copeptin (12.7 (7.3-20.6) pmol·L-1 versus 6.8 (4.4-12.8) pmol·L-1; p=0.015) at baseline than the rest of the cohort. At baseline, MR-proANP (area under the curve (AUC) 0.91; cut-off value 227 pmol·L-1; OR 56, 95% CI 6.9-454.3) and copeptin (AUC 0.70; cut-off value 10.9 pmol·L-1; OR 1.5, 95% CI 1.2-1.9) identified severely diseased patients. After PEA/BPA, levels of MR-proANP (99 (58-145) pmol·L-1; p<0.001) and copeptin (6.3 (3.7-12.6) pmol·L-1; p=0.009) decreased and indicated optimal therapy response (MR-proANP <123 pmol·L-1 (AUC 0.70) and copeptin <10.1 pmol·L-1 (AUC 0.58)).

CONCLUSION

MR-proANP and copeptin levels are affected in CTEPH and decrease after therapy. MR-proANP identifies a severe disease status and optimal therapy response.

The Renal Resistive Index: A New Biomarker for the Follow-up of Vascular Modifications in Systemic Sclerosis

Objective.

The aim of the present retrospective observational study was to evaluate the change of Renal Resistive Index (RRI) over time (ΔRRI) and under treatment in patients with systemic sclerosis (SSc) as well as to correlate these changes with disease complications.

Methods.

Two hundred thirty patients [29 male, median age 57 (IQR 48–67) yrs] were enrolled. At baseline and follow-up (3.43, IQR 2.81–4.45 yrs), we collected the following data: disease variables, nailfold videocapillaroscopy (NVC) pattern, forced vital capacity (FVC), diffusing lung capacity for carbon monoxide (DLCO), systolic pulmonary arterial pressure (sPAP), presence of interstitial lung disease, RRI, evaluation of glomerular filtration rate, and new onset of pulmonary arterial hypertension (PAH).

Results.

RRI value is high in SSc patients with digital ulcers and anticentromere antibodies, active and late NVC patterns, and limited cutaneous SSc. A significant correlation was observed between ΔRRI and ΔsPAP (R = 0.17, P = 0.02), with statistically higher ΔRRI (0.08 ± 0.02 vs 0.03 ± 0.05, P = 0.04) in patients complicated by PAH onset. No other new-onset complication was associated with ΔRRI. The receiver-operating characteristic curve analysis confirmed the predictive role of ΔRRI in development of new PAH (area under the curve 0.84, 95% CI 0.75–0.93, P = 0.02). In patients with SSc never exposed to sildenafil, ΔRRI was higher (0.04 ± 0.05) compared to both patients exposed to sildenafil during the study period (0.01 ± 0.05, P = 0.03) or in those exposed at the time of baseline evaluation (0.00 ± 0.05, P = 0.01).

Conclusion.

RRI and its variation in time are a reliable marker of SSc-related vasculopathy, both in renal and extrarenal compartments.

Systemic Consequences of Pulmonary Hypertension and Right-Sided Heart Failure

Pulmonary hypertension (PH) is a feature of a variety of diseases and continues to harbor high morbidity and mortality. The main consequence of PH is right-sided heart failure which causes a complex clinical syndrome affecting multiple organ systems including left heart, brain, kidneys, liver, gastrointestinal tract, skeletal muscle, as well as the endocrine, immune, and autonomic systems. Interorgan crosstalk and interdependent mechanisms include hemodynamic consequences such as reduced organ perfusion and congestion as well as maladaptive neurohormonal activation, oxidative stress, hormonal imbalance, and abnormal immune cell signaling. These mechanisms, which may occur in acute, chronic, or acute-on-chronic settings, are common and precipitate adverse functional and structural changes in multiple organs which contribute to increased morbidity and mortality. While the systemic character of PH and right-sided heart failure is often neglected or underestimated, such consequences place additional burden on patients and may represent treatable traits in addition to targeted therapy of PH and underlying causes. Here, we highlight the current state-of-the-art understanding of the systemic consequences of PH and right-sided heart failure on multiple organ systems, focusing on self-perpetuating pathophysiological mechanisms, aspects of increased susceptibility of organ damage, and their reciprocal impact on the course of the disease.

Diagnostic and Prognostic Significance of Serum Levels of SeP (Selenoprotein P) in Patients With Pulmonary Hypertension

OBJECTIVE

Despite the recent progress in upfront combination therapy for pulmonary arterial hypertension (PAH), useful biomarkers for the disorder still remain to be developed. SeP (Selenoprotein P) is a glycoprotein secreted from various kinds of cells including pulmonary artery smooth muscle cells to maintain cellular metabolism. We have recently demonstrated that SeP production from pulmonary artery smooth muscle cells is upregulated and plays crucial roles in the pathogenesis of PAH. However, it remains to be elucidated whether serum SeP levels could be a useful biomarker for PAH. Approach and Results: We measured serum SeP levels and evaluated their prognostic impacts in 65 consecutive patients with PAH and 20 controls during follow-up (mean, 1520 days; interquartile range, 1393-1804 days). Serum SeP levels were measured using a newly developed sol particle homogeneous immunoassay. The patients with PAH showed significantly higher serum SeP levels compared with controls. Higher SeP levels (cutoff point, 3.47 mg/L) were associated with the outcome (composite end point of all-cause death and lung transplantation) in patients with PAH (hazard ratio, 4.85 [1.42-16.6]; P<0.01). Importantly, we found that the absolute change in SeP of patients with PAH (ΔSeP) in response to the initiation of PAH-specific therapy significantly correlated with the absolute change in mean pulmonary artery pressure, pulmonary vascular resistance (ΔPVR), and cardiac index (ΔCI; R=0.78, 0.76, and -0.71 respectively, all P<0.0001). Moreover, increase in ΔSeP during the follow-up predicted poor outcome of PAH.

CONCLUSIONS

Serum SeP is a novel biomarker for diagnosis and assessment of treatment efficacy and long-term prognosis in patients with PAH.

Hot topics in the mechanisms of pulmonary arterial hypertension disease: cancer-like pathobiology, the role of the adventitia, systemic involvement, and right ventricular failure

In order to intervene appropriately and develop disease-modifying therapeutics for pulmonary arterial hypertension, it is crucial to understand the mechanisms of disease pathogenesis and progression. We herein discuss four topics of disease mechanisms that are currently highly debated, yet still unsolved, in the field of pulmonary arterial hypertension. Is pulmonary arterial hypertension a cancer-like disease? Does the adventitia play an important role in the initiation of pulmonary vascular remodeling? Is pulmonary arterial hypertension a systemic disease? Does capillary loss drive right ventricular failure? While pulmonary arterial hypertension does not replicate all features of cancer, anti-proliferative cancer therapeutics might still be beneficial in pulmonary arterial hypertension if monitored for safety and tolerability. It was recognized that the adventitia as a cell-rich compartment is important in the disease pathogenesis of pulmonary arterial hypertension and should be a therapeutic target, albeit the data are inconclusive as to whether the adventitia is involved in the initiation of neointima formation. There was agreement that systemic diseases can lead to pulmonary arterial hypertension and that pulmonary arterial hypertension can have systemic effects related to the advanced lung pathology, yet there was less agreement on whether idiopathic pulmonary arterial hypertension is a systemic disease per se. Despite acknowledging the limitations of exactly assessing vascular density in the right ventricle, it was recognized that the failing right ventricle may show inadequate vascular adaptation resulting in inadequate delivery of oxygen and other metabolites. Although the debate was not meant to result in a definite resolution of the specific arguments, it sparked ideas about how we might resolve the discrepancies by improving our disease modeling (rodent models, large-animal studies, studies of human cells, tissues, and organs) as well as standardization of the models. Novel experimental approaches, such as lineage tracing and better three-dimensional imaging of experimental as well as human lung and heart tissues, might unravel how different cells contribute to the disease pathology.

Development of renal function during staged balloon pulmonary angioplasty for inoperable chronic thromboembolic pulmonary hypertension

Balloon pulmonary angioplasty (BPA), for chronic thromboembolic pulmonary hypertension, improves pulmonary and systemic hemodynamics. The kidney might benefit from this effect. However, staged BPA therapy comes along with repetitive administration of contrast agent. This study examined the overall effect of BPA therapy on renal function. This study included consecutive patients who underwent BPA treatment and completed a 6-month follow-up between March 2014 and March 2017. Biomarker-based evaluation of renal function was performed at baseline, consecutively prior to and after each BPA and at 6-month follow-up. The 51 patients underwent an average of 5 (±2) BPA sessions. In this course, patients received 133 (±48; 21-300) mL of contrast agent per session and 691 (±24; 240-1410) mL during the whole sequence. Acute kidney injury occurred after 6 (2.3%) procedures. The creatinine [80.1 (IQR 67.8-96.8) µmol/L vs. 77.4 (IQR 66.9-91.5) µmol/L, p = .02] and urea level [13.7 (IQR10.7-16.6) mmol/L vs. 12.5 (IQR 10.0-15.5) mmol/L, p = .02] decreased from baseline to the 6-month follow-up. The estimated glomerular filtration rate (eGFR) [79 (IQR 59-94) mL/min/m² vs. 79.6 (IQR 67.1-95.0) mL/min/m², p = .11] did not change. The Chronic kidney disease (CKD) stages at baseline were: G1:15; G2:23; G3a:10; G3b:2; G4:1; G5:0. Among patients with a CKD-stage ≥2, analysis revealed an increase of eGFR, decrease of creatinine and urea from baseline to 6-month follow-up. Among those patients, the baseline-CKD-stage improved in 14 (41.2%) patients. BPA therapy improves pulmonary and systemic hemodynamics, with positive effects on renal function. Repetitive administration of contrast agent seems not to be harmful regarding renal function.