Plasma brain natriuretic peptide as a prognostic indicator in patients with primary pulmonary hypertension

Life expectancy in cancer patients with pulmonary thromboembolism: From clinical prognostic biomarkers and paraclinical investigations to therapeutic approaches (Review)

Pulmonary embolisms (PEs) are obstructions of the pulmonary arteries by thrombi, which are emboli and they most frequently originate from the deep venous system of the inferior limbs. Emboli can also come from the inferior vena cava, abdominal and pelvic veins, or the upper body venous system from the right atrium or ventricle of the heart. Thrombi can form in situ inside pulmonary arteries as well. A cancer patient is at a higher risk for thromboembolic phenomena given both the oncological pathological context and also due to the associated medical or surgical treatment they receive. PE is a high-risk medical emergency that is associated with an increased risk of early mortality, with sudden death occurring in 25% of patients. The long-term presence of this condition can result in thromboembolic pulmonary hypertension. The risk of mortality, both in the acute and long-term, is dependent on the severity of the acute form, the recurrence of the embolism and the associated conditions. The majority of deaths associated with PE can be prevented by early diagnosis. The aim of the present review was to describe the various biological and cellular parameters, together with known paraclinical investigations, to assist in the rapid diagnosis of PE. Mortality in patients with PE and neoplastic conditions may be reduced by initiating anticoagulant treatment as soon as possible. PE may be the first manifestation of an underlying silent malignancy or may represent a complication of an already diagnosed malignancy. Exclusion or confirmation of the diagnosis is of utmost importance to avoid unnecessary anticoagulant treatment associated with a high risk of bleeding or to start immediate anticoagulant treatment if required.

Unraveling the genetic landscape of pulmonary arterial hypertension in Indian patients: A transcriptome study

BACKGROUND

Pulmonary hypertension (PH) is the abnormal elevation of pressure in the pulmonary vascular system, with various underlying causes. A specific type of PH is pulmonary arterial hypertension (PAH), a severe condition characterized by high pulmonary arterial pressure resulting from structural changes in distal pulmonary vessels, altered arterial tone, and inflammation. This leads to right ventricular hypertrophy and heart failure. The molecular mechanisms behind PAH are not well understood. This manuscript aims to elucidate these mechanisms using the genetic tool, aiding in diagnosis and treatment selection.

METHOD

In our present study, we have obtained blood samples from both patients with pulmonary arterial hypertension (PAH) and healthy individuals. We conducted a comparative transcriptome analysis to identify genes that are either upregulated or downregulated in PAH patients when compared to the control group. Subsequently, we carried out a validation study focusing on the log2-fold downregulated genes in PAH, employing Quantitative Real-Time PCR for confirmation. Additionally, we quantified the proteins encoded by the validated genes using the ELISA technique.

RESULTS

The results of the transcriptome analysis revealed that 97 genes were significantly upregulated, and 6 genes were significantly downregulated. Among these, we chose to focus on and validate only four of the downregulated genes, as they were directly or indirectly associated with the hypertension pathway. We also conducted validation studies for the proteins encoded by these genes, and the results were consistent with those obtained in the transcriptome analysis.

CONCLUSION

In conclusion, the findings of this study indicate that the four validated genes identified in the context of PAH can be further explored as potential targets for both diagnostic and therapeutic applications.

Understanding pulmonary hypertension: the need for an integrative metabolomics and transcriptomics approach

Pulmonary hypertension (PH), characterised by mean pulmonary arterial pressure (mPAP) >20 mm Hg at rest, is a complex pathophysiological disorder associated with multiple clinical conditions. The high prevalence of the disease along with increased mortality and morbidity makes it a global health burden. Despite major advances in understanding the disease pathophysiology, much of the underlying complex molecular mechanism remains to be elucidated. Lack of a robust diagnostic test and specific therapeutic targets also poses major challenges. This review provides a comprehensive update on the dysregulated pathways and promising candidate markers identified in PH patients using the transcriptomics and metabolomics approach. The review also highlights the need of using an integrative multi-omics approach for obtaining insight into the disease at a molecular level. The integrative multi-omics/pan-omics approach envisaged to help in bridging the gap from genotype to phenotype is outlined. Finally, the challenges commonly encountered while conducting omics-driven studies are also discussed.

Effect of zamicastat on blood pressure and heart rate response to cold pressor test: A double-blind, randomized, placebo-controlled study in healthy subjects

AIMS

Dopamine beta-hydroxylase (DβH) inhibitors, like zamicastat, hold promise for treating pulmonary arterial hypertension. This study aimed to validate the mechanism of action of zamicastat by studying its effect on the overdrive of the sympathetic nervous system (SNS).

METHODS

A single-centre, prospective, double-blind, randomized, placebo-controlled, crossover study evaluated the effect of 400 mg zamicastat in 22 healthy male subjects. Cold pressor test (CPT) was performed at screening and each treatment period on Days -1 and 10. Plasma and 24 h-urine levels of dopamine (DA), epinephrine (EPI) and norepinephrine (NE), and plasma DβH activity, were measured.

RESULTS

Compared to placebo, zamicastat showed a - 4.62 mmHg decrease in systolic blood pressure during the cold stimulus vs. rest phases on Day 10 of CPT (P = .020). Zamicastat decreased mean arterial pressure response to cold stimulus during CPT (-2.62 mmHg; P = .025). At Day 10, zamicastat significantly increased plasma DA, before CPT (12.63 ng/L; P = .040) and after CPT (19.22 ng/L; P = .001) as well as the estimated plasma EPI change from baseline after CPT (P = .040). Inhibition of plasma DβH activity ranged from 19.8% to 25.0%. At Day 10, significant reductions in 24-h urinary excretion of EPI (P = .002) and NE (P = .001) were observed. Zamicastat Cτ geometric mean ± GSD ranged from 45.86 ± 1.46 ng/mL on Day 3 to 58.64 ± 1.52 ng/mL on Day 10, with moderate inter-individual variability (CV: 32.6%-36.6%). Steady state was already achieved on Day 6.

CONCLUSIONS

Our results demonstrated the effect of zamicastat on the overdrive sympathetic response to cold stimulus, confirming its potential as SNS modulator.

Drug-Drug Interaction between Oral Zamicastat and Continuous Epoprostenol Infusion at Steady-State Conditions in Healthy Subjects

This study intended to evaluate the interactions between zamicastat and epoprostenol in healthy human subjects. This was a single-center, open-label, two-period study. In period 1, epoprostenol 8 ng/kg/min was administered alone. In period 2, epoprostenol 8 ng/kg/min was administered following an 8-day treatment with zamicastat. Since the initial dose of epoprostenol showed to be insufficiently tolerated, it was decreased to 6 ng/kg/min. Blood samples were collected to determine the metabolites of epoprostenol and concentrations of zamicastat and its metabolites. A total of 54 subjects were enrolled and data from 28 subjects were available for pharmacokinetic analysis. The epoprostenol plus zamicastat-to-epoprostenol geometric means ratio (GMR) and corresponding 90% confidence interval (CI) for Cav,ss and area under the plasma concentration-time curve from time 0 up to 16 h at steady state (AUC0-16,ss) of the metabolites of epoprostenol were within the acceptance bioequivalence range (80.00%-125.00%). The intrasubject coefficient of variation (ISCV) was below 10% for both parameters, on both metabolites. For zamicastat AUC0-τ,ss, the zamicastat plus epoprostenol-to-zamicastat GMR and corresponding 90% CI were within the bioequivalence acceptance range, while for zamicastat Cmax,ss, the lower limit of the 90% CI was slightly below the acceptance range. For zamicastat metabolites, Cmax,ss and AUC0-τ,ss and the zamicastat plus epoprostenol-to-zamicastat GMR were below the acceptance bioequivalence range. ISCV was between 30% and 41% for Cmax,ss and between 21% and 41% for AUC0-τ,ss, for zamicastat and both metabolites. This study showed that the administration of zamicastat did not significantly modify the cardiovascular effects of epoprostenol and that the interactions between zamicastat and epoprostenol are not expected to be clinically relevant.

Association of delayed diagnosis of pulmonary arterial hypertension with its prognosis

BACKGROUND

Currently, pulmonary hypertension-targeted therapy has been shown to improve the survival of patients with pulmonary artery hypertension (PAH). However, the importance of early diagnosis has not been investigated. Therefore, this study aimed to investigate whether a delayed diagnosis of PAH is associated with its prognosis.

METHODS AND RESULTS

A total of 66 consecutive untreated patients were diagnosed with PAH from January 2008 to December 2021 at the Kagoshima University Hospital. The time from symptom onset to diagnosis correlated with brain natriuretic peptide levels (p < 0.001), right ventricle (RV) Tei index (p < 0.001), and the tricuspid annular plane systolic excursion/systolic pulmonary artery pressure ratio (p = 0.003). These findings suggest that in patients with PAH, RV function declines with increasing time from symptom onset to diagnosis. Furthermore, older patients with PAH appeared to have a longer time from symptom onset to diagnosis. Next, patients were divided into delayed diagnosis (>3 months) and early diagnosis (≤3 months) groups based on the time from symptom onset to diagnosis. Patients were categorized into three groups according to the European Society of Cardiology (or the European Respiratory Society) risk stratification guidelines. Patients diagnosed with PAH within 3 months of symptom onset were significantly in the low- or intermediate-risk groups (p < 0.001). A Kaplan-Meier analysis revealed that the cumulative event-free rate was significantly lower (p < 0.01) in the delayed diagnosis group than in the early diagnosis group. A delayed diagnosis was significantly associated with a worse outcome than an early diagnosis, after adjusting for different sets of confounding factors.

CONCLUSIONS

A delayed PAH diagnosis is associated with a poor prognosis. Early diagnosis of PAH may lead to a low-risk treatment. Furthermore, older patients need more careful screening for PAH.

Significance of Hypocapnia in the Risk Assessment of Patients with Pulmonary Hypertension

Blood gas analysis is part of the diagnostic work-up for pulmonary hypertension (PH). Although some studies have found that the partial pressure of carbon dioxide (PaCO2) is an independent marker of mortality in individuals with pulmonary arterial hypertension (PH Group 1), there is a lack of data regarding the significance of PaCO2 in individuals with different types of PH based on the new 2022 definitions. Therefore, this study analyzed data from 157 individuals who were undergoing PH work-up, including right heart catheterization, using PH definitions from the 2022 European Society of Cardiology/European Respiratory Society guidelines. At diagnosis, N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) levels were significantly higher, but the time-course of NT-pro-BNP levels during treatment was significantly more favorable in individuals with pulmonary arterial hypertension (PH Group 1) who did versus did not have hypocapnia (p = 0.026 and p = 0.017, respectively). These differences based on the presence of hypocapnia were not seen in individuals with PH Groups 2, 3, or 4. In conclusion, using the new definition of PH, hypocapnia may correlate with worse risk stratification at diagnosis in individuals with pulmonary arterial hypertension. However, hypocapnic individuals with pulmonary arterial hypertension may benefit more from disease-specific therapy than those without hypocapnia.

Evaluating the role of serum uric acid in the risk stratification and therapeutic response of patients with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD)

Background: Pulmonary arterial hypertension (PAH) is a malignant pulmonary vascular disease that negatively impacts quality of life, exercise capacity, and mortality. This study sought to investigate the relationship between serum uric acid (UA) level and the disease severity and treatment response of patients with PAH and congenital heart disease (PAH-CHD). Methods: This study included 225 CHD patients and 40 healthy subjects. Serum UA was measured in all patients, and UA levels and haemodynamic parameters were re-evaluated in 20 patients who had received PAH-specific drug treatment for at least 7 ± 1 month. Results: Serum UA levels were significantly higher in PAH-CHD patients than in CHD patients with a normal pulmonary artery pressure and normal subjects (347.7 ± 105.7 μmol/L vs. 278.3 ± 84.6 μmol/L; 347.7 ± 105.7 μmol/L vs. 255.7 ± 44.5 μmol/L, p < 0.05). UA levels in the intermediate and high risk groups were significantly higher than those in the low-risk group (365.6 ± 107.8 μmol/L vs. 311.2 ± 82.8 μmol/L; 451.6 ± 117.6 μmol/L vs. 311.2 ± 82.8 μmol/L, p < 0.05). Serum UA levels positively correlated with mean pulmonary arterial pressure, WHO functional class, pulmonary vascular resistance, and NT-proBNP (r = 0.343, 0.357, 0.406, 0.398; p < 0.001), and negatively with mixed venous oxygen saturation (SvO2) and arterial oxygen saturation (SaO2) (r = -0.293, -0.329; p < 0.001). UA significantly decreased from 352.7 ± 97.5 to 294.4 ± 56.8 μmol/L (p = 0.001) after PAH-specific drug treatment for at least 6 months, along with significant decreases in mean pulmonary arterial pressure and pulmonary vascular resistance and increases in cardiac index and mixed SvO2. Conclusion: Serum UA can be used as a practical and economic biomarker for risk stratification and the evaluation of PAH-specific drug treatment effects for patients with PAH-CHD.

Association of red cell distribution width with pulmonary arterial hypertension in patients with mixed connective tissue disease

BACKGROUND

Pulmonary arterial hypertension (PAH) is a severe complication of mixed connective tissue disease (MCTD) and contributes to increased morbidity and mortality. Still, the demographic characteristics and risk factors of PAH in MCTD remain poorly understood. This study explored risk factors for PAH development in MCTD.

METHODS

Data from patients with MCTD and PAH hospitalized from May 2009 to December 2022 in a single center were collected and compared with patients with MCTD without PAH. The variables were analyzed by logistic regression to identify the factors associated with PAH in patients with MCTD. The receiver-operating characteristic (ROC) curve was used to assess the diagnostic value of the identified factors.

RESULTS

Finally, 119 patients with MCTD were included; 46 had PAH. The mean age at PAH onset and diagnosis was 38.9 ± 13.4 and 39.9 ± 13.7 years, respectively. The median pulmonary arterial systolic pressure (PASP) was 67.0 mmHg. The median brain natriuretic peptide (BNP) level was 180.0 pg/ml at PAH diagnosis. Red cell distribution width (RDW) (OR: 2.128; 95% confidence interval: 1.497-3.026; P < 0.001) was associated with PAH in patients with MCTD. There was a positive correlation between RDW and PASP (r = 0.716, P < 0.001). At a cutoff of 15.2%, RDW had the best sensitivity (80.4%) and specificity (82.2%) for PAH.

CONCLUSION

RDW may serve as a sensitive index to predict PAH in patients with MCTD.

Factors leading to supranormal cardiac index in pediatric pulmonary hypertension patients treated with parenteral prostanoid therapy

Parenteral prostanoid therapy (PPT) can result in supranormal cardiac index (SCI; >4 L/min/m2) in pediatric pulmonary hypertension (PPH) patients. We evaluated the incidence, hemodynamic factors, and outcomes associated with SCI in PPH. This retrospective cohort study included 22 PPH patients on PPT from 2005 to 2020. Hemodynamic profiles were compared between the baseline and 3-6 month follow-up catheterization in the SCI and non-SCI cohorts. Cox regression analysis examined time to composite adverse outcome (CAO; Potts shunt, lung transplant, or death) controlling for initial disease severity. SCI developed in 17 (77%) patients, of whom 11 (65%) developed SCI within 6 months. The SCI cohort was characterized by significant augmentation of cardiac index (CI) and stroke volume (SV) as well as reductions in systemic vascular resistance (SVR) and pulmonary vascular resistance (PVR). Conversely, the non-SCI cohort had unchanged SV despite a modest rise in CI as well as persistent vasoconstriction. After median follow-up of 4.3 years (range 0.2-13 years), non-SCI patients were at significantly increased risk for the CAO (5/5: three deaths, two Potts shunts) compared with SCI patients (5/17: two deaths, three lung transplants; adjusted hazard ratio 14.0 [95% confidence interval: 2.1-91.3], p < 0.001). A majority of PPH patients developed SCI within 6-12 months of starting PPT and demonstrated lower risk of adverse outcomes compared with non-SCI patients. These data suggest that change in SVR and SV after 3-6 months of PPT may be early markers of therapeutic response and prognosis.

Serum Biomarkers in Connective Tissue Disease-Associated Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a life-threatening complication of connective tissue diseases (CTDs) characterised by increased pulmonary arterial pressure and pulmonary vascular resistance. CTD-PAH is the result of a complex interplay among endothelial dysfunction and vascular remodelling, autoimmunity and inflammatory changes, ultimately leading to right heart dysfunction and failure. Due to the non-specific nature of the early symptoms and the lack of consensus on screening strategies-except for systemic sclerosis, with a yearly transthoracic echocardiography as recommended-CTD-PAH is often diagnosed at an advanced stage, when the pulmonary vessels are irreversibly damaged. According to the current guidelines, right heart catheterisation is the gold standard for the diagnosis of PAH; however, this technique is invasive, and may not be available in non-referral centres. Hence, there is a need for non-invasive tools to improve the early diagnosis and disease monitoring of CTD-PAH. Novel serum biomarkers may be an effective solution to this issue, as their detection is non-invasive, has a low cost and is reproducible. Our review aims to describe some of the most promising circulating biomarkers of CTD-PAH, classified according to their role in the pathophysiology of the disease.

Maternal Outcomes Among Pregnant Women With Congenital Heart Disease-Associated Pulmonary Hypertension

BACKGROUND

Studies focused on pregnant women with congenital heart disease (CHD)-associated pulmonary hypertension (PH) are scarce and limited by small sample sizes and single-center design. This study sought to describe the pregnancy outcomes in women with CHD with and without PH.

METHODS

Outcomes for pregnant women with CHD were evaluated retrospectively from 1993 to 2016 and prospectively from 2017 to 2019 from 7 tertiary hospitals. PH was diagnosed on the basis of echocardiogram or catheterization. The incidence of maternal death, cardiac complications, and obstetric and offspring complications was compared for women with CHD and no PH, mild, and moderate-to-severe PH.

RESULTS

A total of 2220 pregnant women with CHD had completed pregnancies. PH associated with CHD was identified in 729 women, including 398 with mild PH (right ventricle to right atrium gradient 30-50 mm Hg) and 331 with moderate-to-severe PH (right ventricle to right atrium gradient >50 mm Hg). Maternal mortality occurred in 1 (0.1%), 0, and 19 (5.7%) women with CHD and no, mild, or moderate-to-severe PH, respectively. Of the 729 patients with PH, 619 (85%) had CHD-associated pulmonary arterial hypertension, and 110 (15%) had other forms of PH. Overall, patients with mild PH had better maternal outcomes than those with moderate-to-severe PH, including the incidence of maternal mortality or heart failure (7.8% versus 39.6%; P<0.001), other cardiac complications (9.0% versus 32.3%; P<0.001), and obstetric complications (5.3% versus 15.7%; P<0.001). Brain natriuretic peptide >100 ng/L (odds ratio, 1.9 [95% CI, 1.0-3.4], P=0.04) and New York Heart Association class III to IV (odds ratio, 2.9 [95% CI, 1.6-5.3], P<0.001) were independently associated with adverse maternal cardiac events in pregnancy with PH, whereas follow-up with a multidisciplinary team (odds ratio, 0.4 [95% CI, 0.2-0.6], P<0.001) and strict antenatal supervision (odds ratio, 0.5 [95% CI, 0.3-0.7], P=0.001) were protective.

CONCLUSIONS

Women with CHD-associated mild PH appear to have better outcomes compared with women with CHD-associated moderate-to-severe PH, and with event rates similar for most outcomes with women with CHD and no PH. Multimodality risk assessment, including PH severity, brain natriuretic peptide level, and New York Heart Association class, may be useful in risk stratification in pregnancy with PH. Follow-up with a multidisciplinary team and strict antenatal supervision during pregnancy may also help to mitigate the risk of adverse maternal cardiac events.

Doppler Echocardiography Combined with NTproBNP/BNP in the Diagnosis of Pulmonary Artery Hypertension Associated with Congenital Heart Disease

Background

Pulmonary artery hypertension (PAH) is a common complication of congenital heart disease (CHD) and is associated with worse outcomes and increased mortality. The Doppler echocardiography (DE) is a commonly used imaging tool for both diagnosis and follow-up examination of PAH. Here is to evaluate the diagnostic performance of DE combined with NTproBNP/BNP as screening strategy in PAH patients with CHD.

Methods

A retrospective study in 64 patients with CHD has been carried out to compare estimate pulmonary artery systolic pressure (PASP) measured with DE to that measured with right heart catheterization (RHC). The Pearson correlation analyses were used to calculate the correlation coefficients between RHC and DE. The Bland-Altman analyses were carried out to assess the agreement between the two methods. ROC analyses were used to evaluate the diagnostic performance of DE, NTproBNP/BNP, and DE combined with NTproBNP/BNP.

Results

Our data have demonstrated that a mild correlation (r = 0.4401, P < 0.01) was observed between PASP (78.1 ± 29.0 mmHg) measured during RHC and PASP (74.9 ± 19.7 mmHg) as estimated using DE. The Bland-Altman analysis demonstrated that the bias for DE PASP estimates was 3.2 mmHg with 95% limits of agreement ranging from -49.53 to 55.90 mmHg. The results of DE showed an AUC of 0.848 (95% CI = 0.666-1; P < 0.001), the sensitivity of which was 98.3% and the specificity was 77.8%. The AUC of NTproBNP/BNP for the identification of PAH was 0.804 (95% CI = 0.651-0.956; P < 0.001), the sensitivity of which was 81.4% and the specificity was 87.5%. The AUC of DE combined with NTproBNP/BNP was 0.857 (95% CI = 0.676-1; P < 0.001), of which sensitivity was 100% and specificity was 77.8%. The positive predictive value (PPV) and negative predictive value (NPV) were 96.6% and 100%, respectively.

Conclusions

Our study shows that the Doppler echocardiography combined with NTproBNP/BNP has better diagnostic performance in pulmonary artery hypertension associated with congenital heart disease, especially when DE negative screening in PAH patients.

The Prognostic Value of B-Type Natriuretic Peptide in Patients With Cardiac Sarcoidosis Without Heart Failure: Insights From ILLUMINATE-CS

Background The prognostic role of BNP (B-type natriuretic peptide) in patients with cardiac sarcoidosis without evident heart failure is unknown. Methods and Results This is a post hoc analysis of ILLUMINATE-CS (Illustration of the Management and Prognosis of Japanese Patients With Cardiac Sarcoidosis), a multicenter, retrospective, and observational study that evaluated the clinical characteristics and prognosis of cardiac sarcoidosis. We analyzed patients with cardiac sarcoidosis without evident heart failure at the time of diagnosis. The association between baseline BNP levels and prognosis was investigated. The primary end point was the combined end point of all-cause death, heart failure hospitalization, and fatal ventricular arrhythmia. In total, 238 patients (61.0±11.1 years, 37% men) were analyzed, and 61 primary end points were observed during a median follow-up period of 3.0 (interquartile range, 1.7-5.8) years. Patients with high BNP (BNP above the median value of BNP) were older and had a lower renal function and left ventricular ejection fraction than those with low BNP values. Kaplan-Meier curve analysis indicated that high BNP levels were significantly associated with a high incidence of primary end points (log-rank P=0.004), and this association was retained even in multivariable Cox regression (hazard ratio, 2.06 [95% CI, 1.19-3.55]; P=0.010). Log-transformed BNP as a continuous variable was associated with the primary end point (hazard ratio, 2.12 [95% CI, 1.31-3.43]; P=0.002). Conclusions High baseline BNP level was an independent predictor of future adverse events in patients with cardiac sarcoidosis without heart failure at the time of diagnosis. Registration URL: https://www.umin.ac.jp/english/; Unique Identifier: UMIN-CTR: UMIN000034974.

Impact of Exercise-Induced Pulmonary Hypertension on Right Ventricular Function and on Worsening of Cardiovascular Risk in HIV Patients

Background and Aim: Exercise-induced pulmonary hypertension (ExPH) predicts clinical outcomes, such as all-cause mortality and cardiovascular (CV) hospitalizations, in patients with dyspnea on effort. We investigated its prognostic significance in human immunodeficiency virus (HIV)-affected patients. Methods: In 52 consecutive HIV patients with either low (n = 47) or intermediate probability (n = 5) of PH at rest, we evaluated—at time 0 and after 2 years—the prognostic determinants of CV risk, according to the 2015 European Society of Cardiology (ESC)/European Respiratory Society (ERS) Guidelines. Patients were classified with or without ExPH at stress echocardiography (ESE) and cardiopulmonary exercise test (CPET). We then related ExPH at time 0 with clinical worsening (CV risk score increase >20% after 2 years). Results: Right ventricle (RV) systolic function was significantly reduced in patients with ExPH compared to those without ExPH at CPET. This also occurred in patients with intermediate/high probability compared to those with low probability of ExPH at ESE. The former exhibited worse values of TAPSE and FAC (p < 0.001 and p = 0.01, respectively). A significantly higher proportion of patients with ExPH (CPET) or with intermediate/high probability of ExPH (ESE) had higher sPAP (p < 0.001), mPAP (p = 0.004) and higher TRV (p = 0.006), as well as higher right atrial area (p < 0.001) and indexed right atrial volume (p = 0.004). Total pulmonary vascular resistance (expressed by the ratio between TRV and the velocity-time integral at the level of the right ventricular outflow tract) was higher both in patients with ExPH and in those with intermediate/high probability of ExPH (p < 0.001). Patients with intermediate/high probability of ExPH at ESE showed a trend (p = 0.137) towards clinical worsening compared to those with low probability of ExPH. No patients with low probability of ExPH had a >20% increased CV risk score after 2 years. We found an association between higher NT-proBNP and the presence or intermediate/high probability of ExPH after 2 years (p = 0.048 at CPET, p = 0.033 at ESE). Conclusions: The assessment of ExPH may predict a trend of increasing CV risk score over time. If confirmed at a longer follow-up, ExPH could contribute to better risk stratification in HIV patients.

Biomarkers in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a severe medical condition characterized by elevated pulmonary vascular resistance (PVR), right ventricular (RV) failure, and death in the absence of appropriate treatment. The progression and prognosis are strictly related to the etiology, biochemical parameters, and treatment response. The gold-standard test remains right-sided heart catheterization, but dynamic monitoring of systolic pressure in the pulmonary artery is performed using echocardiography. However, simple and easily accessible non-invasive assays are also required in order to monitor this pathology. In addition, research in this area is in continuous development. In recent years, more and more biomarkers have been studied and included in clinical guidelines. These biomarkers can be categorized based on their associations with inflammation, endothelial cell dysfunction, cardiac fibrosis, oxidative stress, and metabolic disorders. Moreover, biomarkers can be easily detected in blood and urine and correlated with disease severity, playing an important role in diagnosis, prognosis, and disease progression.

Regnase-1 Prevents Pulmonary Arterial Hypertension Through mRNA Degradation of Interleukin-6 and Platelet-Derived Growth Factor in Alveolar Macrophages

BACKGROUND

Pulmonary arterial hypertension (PAH) is a type of pulmonary hypertension (PH) characterized by obliterative pulmonary vascular remodeling, resulting in right-sided heart failure. Although the pathogenesis of PAH is not fully understood, inflammatory responses and cytokines have been shown to be associated with PAH, in particular, with connective tissue disease-PAH. In this sense, Regnase-1, an RNase that regulates mRNAs encoding genes related to immune reactions, was investigated in relation to the pathogenesis of PH.

METHODS

We first examined the expression levels of ZC3H12A (encoding Regnase-1) in peripheral blood mononuclear cells from patients with PH classified under various types of PH, searching for an association between the ZC3H12A expression and clinical features. We then generated mice lacking Regnase-1 in myeloid cells, including alveolar macrophages, and examined right ventricular systolic pressures and histological changes in the lung. We further performed a comprehensive analysis of the transcriptome of alveolar macrophages and pulmonary arteries to identify genes regulated by Regnase-1 in alveolar macrophages.

RESULTS

ZC3H12A expression in peripheral blood mononuclear cells was inversely correlated with the prognosis and severity of disease in patients with PH, in particular, in connective tissue disease-PAH. The critical role of Regnase-1 in controlling PAH was also reinforced by the analysis of mice lacking Regnase-1 in alveolar macrophages. These mice spontaneously developed severe PAH, characterized by the elevated right ventricular systolic pressures and irreversible pulmonary vascular remodeling, which recapitulated the pathology of patients with PAH. Transcriptomic analysis of alveolar macrophages and pulmonary arteries of these PAH mice revealed that Il6, Il1b, and Pdgfa/b are potential targets of Regnase-1 in alveolar macrophages in the regulation of PAH. The inhibition of IL-6 (interleukin-6) by an anti-IL-6 receptor antibody or platelet-derived growth factor by imatinib but not IL-1β (interleukin-1β) by anakinra, ameliorated the pathogenesis of PAH.

CONCLUSIONS

Regnase-1 maintains lung innate immune homeostasis through the control of IL-6 and platelet-derived growth factor in alveolar macrophages, thereby suppressing the development of PAH in mice. Furthermore, the decreased expression of Regnase-1 in various types of PH implies its involvement in PH pathogenesis and may serve as a disease biomarker, and a therapeutic target for PH as well.

An explorative metabolomic analysis of the endothelium in pulmonary hypertension

Pulmonary hypertension (PH) is classified into five clinical diagnostic groups, including group 1 [idiopathic pulmonary arterial hypertension (IPAH) and connective tissue disease-associated PAH (CTD-aPAH)] and group 4 (chronic thromboembolic pulmonary hypertension (CTEPH)). PH is a progressive, life-threatening, incurable disease. The pathological mechanisms underlying PH remain elusive; recent evidence has revealed that abnormal metabolic activities in the endothelium may play a crucial role. This research introduces a novel approach for studying PH endothelial function, building on the genome-scale metabolic reconstruction of the endothelial cell (EC) to investigate intracellular metabolism. We demonstrate that the intracellular metabolic activities of ECs in PH patients cluster into four phenotypes independent of the PH diagnosis. Notably, the disease severity differs significantly between the metabolic phenotypes, suggesting their clinical relevance. The significant metabolic differences between the PH phenotypes indicate that they may require different therapeutic interventions. In addition, diagnostic capabilities enabling their identification is warranted to investigate whether this opens a novel avenue of precision medicine.

Prognostic value of brain natriuretic peptides in patients with pulmonary arterial hypertension: A systematic review and meta-analysis

BACKGROUND

Multiple biomarkers have been investigated in the risk stratification of patients with pulmonary arterial hypertension (PAH). This systematic review and meta-analysis is the first to investigate the prognostic value of (NT-pro)BNP in patients with PAH.

METHODS

A systematic literature search was performed using MEDLINE, Embase, Web of Science, the Cochrane Library and Google scholar to identify studies on the prognostic value of baseline (NT-pro)BNP levels in PAH. Studies reporting hazard ratios (HR) for the endpoints mortality or lung transplant were included. A random effects meta-analysis was performed to calculate the pooled HR of (NT-pro)BNP levels at the time of diagnosis. To account for different transformations applied to (NT-pro)BNP, the HR was calculated for a 2-fold difference of the weighted mean (NT-pro)BNP level of 247 pmol/L, for studies reporting a HR based on a continuous (NT-pro)BNP measurement.

RESULTS

Sixteen studies were included, representing 6999 patients (mean age 45.2-65.0 years, 97.3% PAH). Overall, 1460 patients reached the endpoint during a mean follow-up period between 1 and 10 years. Nine studies reported HRs based on cut-off values. The risk of mortality or lung transplant was increased for both elevated NT-proBNP and BNP with a pooled HR based on unadjusted HRs of 2.75 (95%-CI: 1.86-4.07) and 3.87 (95% CI 2.69-5.57) respectively. Six studies reported HRs for (NT-pro)BNP on a continues scale. A 2-fold difference of the weighted mean NT-proBNP resulted in an increased risk of mortality or lung transplant with a pooled HR of 1.17 (95%-CI: 1.03-1.32).

CONCLUSIONS

Increased levels of (NT-pro)BNP are associated with a significantly increased risk of mortality or lung transplant in PAH patients.

An Overview of Circulating Pulmonary Arterial Hypertension Biomarkers

Pulmonary arterial hypertension (PAH), also known as Group 1 Pulmonary Hypertension (PH), is a PH subset characterized by pulmonary vascular remodeling and pulmonary arterial obstruction. PAH has an estimated incidence of 15-50 people per million in the United States and Europe, and is associated with high mortality and morbidity, with patients' survival time after diagnosis being only 2.8 years. According to current guidelines, right heart catheterization is the gold standard for diagnostic and prognostic evaluation of PAH patients. However, this technique is highly invasive, so it is not used in routine clinical practice or patient follow-up. Thereby, it is essential to find new non-invasive strategies for evaluating disease progression. Biomarkers can be an effective solution for determining PAH patient prognosis and response to therapy, and aiding in diagnostic efforts, so long as their detection is non-invasive, easy, and objective. This review aims to clarify and describe some of the potential new candidates as circulating biomarkers of PAH.

The frequency of pulmonary hypertension in chronic obstructive pulmonary disease of geriatric patients: a narrative literature review

Background

Pulmonary hypertension (PH) is a serious complication with complex pathogenesis in the natural history of chronic obstructive pulmonary disease COPD, with a progressively increasing frequency with a meanwhile decreasing in functional capacity.

Purpose

Assessment of the incidence, pathogenesis, peculiarities, and complications of PH in COPD in geriatric population worldwide.

Methods

We performed an analysis of randomized, retrospective, and prospective clinical, case-control and observational studies, published at the international level, according to the subject studied and target population. Four hundred ninety-seven full articles were identified after the search through engine Google Search and databases PubMed, Hinari, SpringerLink, and Scopus (Elsevier) according to the keywords and subsequent filters.

Results

Depending on various factors, like the population examined, the definition used for mPAP (mPAP> 20 mm Hg or ≥25 mm Hg), the severity of the lung disease, and the method of measuring PAP, a varied incidence of COPD patients with PH complication was discovered, namely 10–91%. PH prevalence increases with the COPD severity. The presence of PH is associated with acute exacerbations of COPD, reduced survival, and increasing expenses for healthcare programs. Mild to moderate levels of PH (mPAP 25–34 mm Hg) are relatively common in COPD and usually are associated with severe airflow obstruction or parenchymal destruction. Only a minority of patients (1–5%) have severe PH (mPAP ≥35 mm Hg).

Conclusions

Diagnosis of PH in COPD is difficult, especially in a mild form, and requires a clinical approach associated with a comprehensive set of investigations for confirming the etiology, evaluation of the functional and hemodynamical impairment severity, and important factors in the appropriate treatment election.

Abnormal Liver Function Tests Were Related to Short- and Long-Term Prognosis in Critically Ill Patients With Primary Pulmonary Hypertension

Aim

The aim of this study was to examine the utility of liver function tests (LFTs) in predicting the prognosis of critically ill patients with primary pulmonary hypertension (PPH) with/without liver disease.

Methods

We retrieved the Medical Information Mart for Intensive Care III (MIMIC-III) database to acquire clinical data. From the database, we recruited adult patients that were equal to or older than 18 years with primary pulmonary hypertension (PPH) discharge from intensive care unit (ICU). Then, the relationship between LFTs and duration of hospitalization and ICU stays was examined based on the Spearman correlation. The chi-square assessment was conducted to examine the correlation between LFTs and death rates. Survival curves were plotted with the aid of the Kaplan-Meier technique, and the curves were subsequently compared utilizing the log-rank test. The LFTs were identified as independent predictive variables of death according to the results of multivariable logistic regression. The specificity and sensitivity for mortality were calculated utilizing receiver operating characteristic (ROC) curves and the area under the curve (AUC).

Results

In total, 198 patients satisfying the inclusion criteria were recruited, among which there were 23 patients with liver disease. Only ALB was correlated with the length of ICU stay in the total PPH group. ALB independently served as a risk variable for hospital mortality and 90-day mortality and was significantly associated with 90-day and 4-year survival rates in both total PPH and PPH without liver disease. AST was correlated with hospital mortality and 90-day survival curves in both total PPH and PPH without liver disease and independently served as a risk factor for hospital and 90-day mortality only in the total PPH group. ALT independently acted as a risk variable for hospital mortality and total bilirubin was correlated with hospital mortality in the total group. The diagnostic performance of the predictive model combining the LFTs was moderately good for the hospital, 90-day, and 4-year mortality. Both Modelı End-Stage ıLiverı Disease (MELD) score and albumin-bilirubin (ALBI) score were independent risk factors for short- and long-term prognosis. And they were also significantly associated with short- and long-term prognosis.

Conclusion

Among critically ill patients with PPH and with or without liver illness, aberrant LFT was linked to short- and long-term prognoses.

Cardiovascular Biomarkers: Lessons of the Past and Prospects for the Future

Cardiovascular diseases (CVDs) are a major healthcare burden on the population worldwide. Early detection of this disease is important in prevention and treatment to minimise morbidity and mortality. Biomarkers are a critical tool to either diagnose, screen, or provide prognostic information for pathological conditions. This review discusses the historical cardiac biomarkers used to detect these conditions, discussing their application and their limitations. Identification of new biomarkers have since replaced these and are now in use in routine clinical practice, but still do not detect all disease. Future cardiac biomarkers are showing promise in early studies, but further studies are required to show their value in improving detection of CVD above the current biomarkers. Additionally, the analytical platforms that would allow them to be adopted in healthcare are yet to be established. There is also the need to identify whether these biomarkers can be used for diagnostic, prognostic, or screening purposes, which will impact their implementation in routine clinical practice.

The Right Heart Network and Risk Stratification in Pulmonary Arterial Hypertension

BACKGROUND

Prognosis in pulmonary arterial hypertension (PAH) is closely related to indexes of right ventricular function. A better understanding of their relationship may provide important implications for risk stratification in PAH.

RESEARCH QUESTION

Can clinical network graphs inform risk stratification in PAH?

STUDY DESIGN AND METHODS

The study cohort consisted of 231 patients with PAH followed up for a median of 7.1 years. An undirected, correlation network was used to visualize the relationship between clinical features in PAH. This network was enriched for right heart parameters and included N-terminal pro-hormone B-type natriuretic peptide (NT-proBNP), comprehensive echocardiographic parameters, and hemodynamics, as well as 6-min walk distance (6MWD), vital signs, laboratory data, and diffusing capacity for carbon monoxide (Dlco). Connectivity was assessed by using eigenvector and betweenness centrality to reflect global and regional connectivity, respectively. Cox proportional hazards regression was used to model event-free survival for the combined end point of death or lung transplantation.

RESULTS

A network of closely intertwined features centered around NT-proBNP with 6MWD emerging as a secondary hub were identified. Less connected nodes included Dlco, systolic BP, albumin, and sodium. Over the follow-up period, death or transplantation occurred in 92 patients (39.8%). A strong prognostic model was achieved with a Harrell's C-index of 0.81 (0.77-0.85) when combining central right heart features (NT-proBNP and right ventricular end-systolic remodeling index) with 6MWD and less connected nodes (Dlco, systolic BP, albumin, sodium, sex, connective tissue disease etiology, and prostanoid therapy). When added to the baseline risk model, serial change in NT-proBNP significantly improved outcome prediction at 5 years (increase in C-statistic of 0.071 ± 0.024; P = .003).

INTERPRETATION

NT-proBNP emerged as a central hub in the intertwined PAH network. Connectivity analysis provides explainability for feature selection and combination in outcome models.

Utility of Plasma Volume Status in Ambulatory Patients with Pulmonary Hypertension

Plasma volume status (PVS) is a noninvasive estimate of intravascular volume status. We studied the utility of PVS to predict short‐term outcomes in patients with pulmonary hypertension. Patients with lower PVS had decreased risk of hospitalization and death within 90 days of clinic visit, compared to those with higher PVS.

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.

Advances in the management of pulmonary arterial hypertension

The management of pulmonary arterial hypertension (PAH) has significantly evolved over the last decades in the wake of more sensitive diagnostics and specialized clinical programs that can provide focused medical care. In the current era of PAH care, 1-year survival rates have increased to 86%–90% from 65% in the 1980s, and average long-term survival has increased to 6 years from 2.8 years. The heterogeneity in the etiology and disease course has opened doors to focusing research in phenotyping the disease and understanding the pathophysiology at a cellular and genetic level. This may eventually lead to precision medicine and the development of medications that may prevent or reverse pulmonary vascular remodeling. With more insight, clinical trial designs and primary end-points may change to identify the true survival benefit of pharmacotherapy. Identifying responders from non-responders to therapy may help provide individualized patient-centered care rather than an algorithm-based approach. The purpose of this review is to highlight the latest advances in screening, diagnosis, and management of PAH.

Novel Experimental Therapies for Treatment of Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a progressive and devastating disease characterized by pulmonary artery vasoconstriction and vascular remodeling leading to vascular rarefaction with elevation of pulmonary arterial pressures and pulmonary vascular resistance. Often PAH will cause death from right heart failure. Current PAH-targeted therapies improve functional capacity, pulmonary hemodynamics and reduce hospitalization. Nevertheless, today PAH still remains incurable and is often refractory to medical therapy, underscoring the need for further research. Over the last three decades, PAH has evolved from a disease of unknown pathogenesis devoid of effective therapy to a condition whose cellular, genetic and molecular underpinnings are unfolding. This article provides an update on current knowledge and summarizes the progression in recent advances in pharmacological therapy in PAH.

Right Ventricular Strain, Brain Natriuretic Peptide, and Mortality in Congenital Diaphragmatic Hernia

Rationale: Brain-type natriuretic peptide (BNP) correlates with pulmonary hypertension as demonstrated by echocardiogram in congenital diaphragmatic hernia (CDH); however, its association with right ventricular (RV) function and mortality is unknown.Objectives: To characterize the relationships between echocardiogram-derived RV strain, BNP, and mortality in diaphragmatic hernia.Methods: We performed a single-center retrospective cohort study of infants with CDH and at least one BNP-echocardiogram pair within a 24-hour period. RV global longitudinal strain (GLS) and free-wall strain (FWS) were measured on existing echocardiograms. Associations among strain, BNP, and mortality were tested using mixed-effect linear and logistic regression models. Survival analysis was stratified by BNP and strain abnormalities.Results: There were 220 infants with 460 BNP-echocardiogram pairs obtained preoperatively (n = 237), ≤1 week postoperatively (n = 35), and >1 week postoperatively ("recovery"; n = 188). Strain improved after repair (P < 0.0001 for all periods). Higher BNP level was associated with worse strain in recovery but not before or immediately after operation (estimate [95% confidence interval] for recovery: GLS, 1.03 [0.50-1.57]; P = 0.0003; FWS, 0.62 [0.01-1.22]; P = 0.047). BNP and strain abnormalities were associated with an extracorporeal-membrane oxygenation requirement. Higher BNP level in recovery was associated with greater mortality (odds ratio, 11.2 [1.2-571.3]; P = 0.02). Abnormal strain in recovery had high sensitivity for detection of mortality (100% for GLS; 100% for FWS) but had low specificity for detection of mortality (28% for GLS; 48% for FWS).Conclusions: Persistent RV dysfunction after CDH repair may be detected by a high BNP level and abnormal RV strain.

Use of Handheld Ultrasound to Estimate Right Atrial Pressure in a Pulmonary Hypertension Clinic

RATIONALE

Point-of-care ultrasonography is an invaluable asset for inpatient decision-making. Whether handheld ultrasound can be utilized in the outpatient management of pulmonary hypertension (PH) is unknown.

OBJECTIVES

We investigated whether a handheld ultrasound estimate of right atrial pressure correlates with B-type natriuretic peptide (BNP) and clinical outcome over time in PH outpatients.

METHODS

This prospective study included outpatients in a PH Comprehensive Care Center clinic who had a same-day BNP level. We used a handheld ultrasound to measure inferior vena cava (IVC) size and collapsibility, which were used to estimate right atrial pressure (eRAP) and categorize it as normal, intermediate, or high. Correlation analysis was used to compare these ultrasound measurements to BNP at baseline and over time. Cox regression was used to determine if these measurements were associated with time to clinical worsening.

RESULTS

Ninety patients (60% Group 1 PH) were enrolled. Patients with an intermediate or high eRAP category at baseline had higher BNP levels than patients with normal eRAP. For every transition in eRAP category (e.g. from normal to intermediate) between clinic visits, BNP changed by an average of 155 pg/mL (95% CI 84 to 227). Higher baseline eRAP category was independently associated with more than two-fold increased risk for clinical worsening (HR 2.44, 95% CI 1.47-4.07).

CONCLUSIONS

Right atrial pressure estimated by portable handheld ultrasound correlates with BNP at baseline and serially over time. Furthermore, eRAP is independently associated with clinical worsening. The use of portable handheld ultrasound to estimate right atrial pressure should be considered in PH clinics. Clinical trial registered at clinicaltrials.gov (NCT02873039).

Soluble ST2 and mixed venous oxygen saturation for prediction of mortality in patients with pulmonary hypertension

Background

Although soluble suppression of tumorigenicity-2 (sST2) has been identified as a clinical biomarker for pulmonary hypertension (PH) by previous studies, the implication of sST2 combined with hemodynamic parameters in PH has not been well studied. This study aimed to evaluate the relationship between sST2 and hemodynamic parameters and to evaluate the predictive value of sST2 for mortality in patients with PH.

Methods

One hundred eighty-four incident patients with PH and 14 healthy controls were retrospectively enrolled by Shanghai Pulmonary Hospital for this retrospective study. After all patients underwent right heart catheterization, blood samples were collected and serum sST2 concentration was assessed by the Presage™ ST2 assay. Kaplan-Meier curve and Cox regression analyses were used to predict survival and the association between survival and different factors such as sST2, SvO₂.

Results

During a follow-up of 44.9 (IQR 28.5–64.4) months, 65 patients died. The median concentration of sST2 in PH patients was 33.1 ng/mL, which is higher than that in control group (23.1 ng/mL, P=0.005). Furthermore, for PH group, the level of sST2 was higher in non-survivors than that in survivors. Cox regression analyses demonstrated that sST2 and SvO₂ were independent risk factors for survival. In Kaplan-Meier curve analyses, elevated sST2 level and reduced SvO₂ predicted a poor outcome for patients with PH.

Conclusions

Higher sST2 was independently associated with increased mortality, as well as lower SvO₂ in patients with PH. Especially, the combination of higher sST2 and lower SvO₂ had the strongest predictive value of mortality in patients with PH.

Comorbidity in idiopathic pulmonary fibrosis - what can biomarkers tell us?

Idiopathic pulmonary fibrosis (IPF) is characterized by progressive parenchymal scarring, leading to dyspnoea, respiratory failure and premature death. Although IPF is confined to the lungs, the importance of IPF comorbidities such as pulmonary hypertension and ischaemic heart disease, lung cancer, emphysema/chronic obstructive pulmonary disease, gastroesophageal reflux, sleep apnoea and depression has been increasingly recognized. These comorbidities may be associated with increased mortality and significant loss of quality of life, so their identification and management are vital. The development of good-quality biomarkers could lead to numerous gains in the management of these patients. Biomarkers can be used for the identification of predisposed individuals, early diagnosis, assessment of prognosis, selection of best treatment and assessment of response to treatment. However, the role of biomarkers for IPF comorbidities is still quite limited, and mostly based on evidence coming from populations without IPF. The future development of new biomarker studies could be informed by those that have been studied independently for each of these conditions. For now, clinicians should be mostly attentive to clinical manifestations of IPF comorbidities, and use validated diagnostic methods for diagnosis. As research on biomarkers of most common diseases continues, it is expected that useful biomarkers are developed for these diseases and then validated for IPF populations. The reviews of this paper are available via the supplemental material section.

Update on pediatric pulmonary arterial hypertension

PURPOSE OF REVIEW

Pulmonary arterial hypertension (PAH) causes high morbidity and mortality in children. In this review, we discuss advances in diagnosis and treatment of this disorder.

RECENT FINDINGS

Proceedings published from the 2018 World Symposium updated the definition of pulmonary hypertension to include all adults and children with mean pulmonary artery pressure more than 20 mmHg. Targeted PAH therapy is increasingly used off-label, but in 2017, bosentan became the first Food and Drug Administration-targeted PAH therapy approved for use in children.

SUMMARY

In recent years, advanced imaging and clinical monitoring have allowed improved risk stratification of pulmonary hypertension patients. New therapies, approved in adults and used off-label in pediatric patients, have led to improved outcomes for affected children.

Pulmonary Hypertension

Pulmonary hypertension is the term used to describe a group of disorders characterized by abnormally high pressures in the pulmonary arteries. Initial evaluation is focused on identifying the cause, which helps guide appropriate treatment. Pulmonary hypertension is often a feature of advanced common diseases, such as chronic obstructive pulmonary disease and left heart disease, and treatment is focused primarily on the underlying disease. More rarely, pulmonary hypertension results from chronic organized thromboemboli or a primary vasculopathy. The former requires evaluation for surgical intervention, and the latter is treated with advanced medical therapies.

Neurohormonal modulation in pulmonary arterial hypertension

Pulmonary hypertension is a fatal condition of elevated pulmonary pressures, complicated by right heart failure. Pulmonary hypertension appears in various forms; one of those is pulmonary arterial hypertension (PAH) and is particularly characterised by progressive remodelling and obstruction of the smaller pulmonary vessels. Neurohormonal imbalance in PAH patients is associated with worse prognosis and survival. In this back-to-basics article on neurohormonal modulation in PAH, we provide an overview of the pharmacological and nonpharmacological strategies that have been tested pre-clinically and clinically. The benefit of neurohormonal modulation strategies in PAH patients has been limited by lack of insight into how the neurohormonal system is changed throughout the disease and difficulties in translation from animal models to human trials. We propose that longitudinal and individual assessments of neurohormonal status are required to improve the timing and specificity of neurohormonal modulation strategies. Ongoing developments in imaging techniques such as positron emission tomography may become helpful to determine neurohormonal status in PAH patients in different disease stages and optimise individual treatment responses.

Increased MAO-A Activity Promotes Progression of Pulmonary Arterial Hypertension

Monoamine oxidases (MAOs), a class of enzymes bound to the outer mitochondrial membrane, are important sources of reactive oxygen species. Increased MAO-A activity in endothelial cells and cardiomyocytes contributes to vascular dysfunction and progression of left heart failure. We hypothesized that inhibition of MAO-A can be used to treat pulmonary arterial hypertension (PAH) and right ventricular (RV) failure. MAO-A levels in lung and RV samples from patients with PAH were compared with levels in samples from donors without PAH. Experimental PAH was induced in male Sprague-Dawley rats by using Sugen 5416 and hypoxia (SuHx), and RV failure was induced in male Wistar rats by using pulmonary trunk banding (PTB). Animals were randomized to receive either saline or the MAO-A inhibitor clorgyline at 10 mg/kg. Echocardiography and RV catheterization were performed, and heart and lung tissues were collected for further analysis. We found increased MAO-A expression in the pulmonary vasculature of patients with PAH and in experimental experimental PAH induced by SuHx. Cardiac MAO-A expression and activity was increased in SuHx- and PTB-induced RV failure. Clorgyline treatment reduced RV afterload and pulmonary vascular remodeling in SuHx rats through reduced pulmonary vascular proliferation and oxidative stress. Moreover, clorgyline improved RV stiffness and relaxation and reversed RV hypertrophy in SuHx rats. In PTB rats, clorgyline had no direct clorgyline had no direct effect on the right ventricle effect. Our study reveals the role of MAO-A in the progression of PAH. Collectively, these findings indicated that MAO-A may be involved in pulmonary vascular remodeling and consecutive RV failure.

Longitudinal B-Type Natriuretic Peptide Levels Predict Outcome in Infants with Congenital Diaphragmatic Hernia

OBJECTIVE

To evaluate B-type natriuretic peptide (BNP) as a longitudinal biomarker of clinical outcome in infants with congenital diaphragmatic hernia (CDH).

STUDY DESIGN

We conducted a retrospective study of 49 infants with CDH, classifying the cohort by respiratory status at 56 days, based on a proposed definition of bronchopulmonary dysplasia for infants ≥32 weeks' gestation: good outcome (alive with no respiratory support) and poor outcome (ongoing respiratory support or death). BNP levels were available at age 1-5 weeks. Longitudinal BNP trends were assessed using mixed-effects modeling. Receiver operating characteristic curves were generated to identify BNP cutoffs maximizing correct outcome classification at each time point. The time to reach BNP cutoff by outcome was assessed using Kaplan-Meier curves for weeks 3-5.

RESULTS

Twenty-nine infants (59%) had a poor outcome. Infants with a poor outcome were more likely than those with a good outcome to have liver herniated into the thorax (90% vs 50%; P = .002) and to undergo nonprimary repair (93% vs 35%; P < .001). Mixed-effects modeling demonstrated a differing decline in BNP over time by outcome group (P = .003 for interaction). BNP accurately predicted outcome at 3-5 weeks (area under the curve, 0.81-0.82). BNP cutoffs that maximized correct outcome classification decreased over time from 285 pg/mL at 3 weeks to 100 pg/mL at 4 weeks and 48 pg/mL at 5 weeks. Time to reach the cutoffs of 100 pg/mL and 48 pg/mL were longer in the poor outcome group (log-rank P = .006 and <.0001, respectively).

CONCLUSIONS

Elevated BNP accurately predicts poor outcome in infants with CDH at age 3-5 weeks, with declining cutoffs over 3-5 weeks of age.

The prognostic effect of brain natriuretic peptide levels on outcomes of hospitalized patients with COVID-19

Natriuretic peptides are biomarkers of myocardial stress and are frequently elevated among patients with severe respiratory illnesses, typically in the absence of elevated cardiac-filling pressures or clinical heart failure. Elevation of brain natriuretic peptide (BNP) or NT-proBNP is associated with worse outcomes among patients with Acute Respiratory Distress Syndrome (ARDS). We conducted a retrospective cohort study based on a comprehensive review of Electronic Medical Records (EMRs) of patients with Coronavirus Disease 2019 (COVID-19) to evaluate whether BNP on admission has prognostic value on mortality and hospital length of stay (LOS) among patients admitted with confirmed COVID-19 along with the inclusion of additional prognostic variables. Overall, 146 patients were included after analyzing 230 patients' EMR and excluding potential confounding factors for abnormal BNP. Our statistical analysis did not show a statistically significant association between BNP level and mortality rate (P = 0.722) or ICU LOS ( P = 0.741). A remarkable secondary outcome to our study was that impaired renal function (GFR<60) on admission was significantly associated with an increased mortality rate (P = 0.026) and an increased ICU LOS (P = 0.022). Although various studies have presented the predictive role of pro-BNP among patients with respiratory distress in the past years, our study did not find BNP to be an accurate predictive and prognostic factor among patients with COVID-19 in our study population. Renal impairment and high Acute Physiology and Chronic Health Evaluation (APACHE) II scores on admission, on the other hand, have demonstrated to be strong predictors for COVID-19 morbidity and mortality. This study could represent an introduction to more prominent multicenter studies to evaluate additional prognostic factors and minimize the ordering of nonspecific testing.

[Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation (Sechenov University), Moscow]

Aim      To study changes in markers for myocardial direct injury and dysfunction and endothelial dysfunction (ED) indexes in patients with indolent lymphoma during the antitumor treatment.Material and methods  Current antitumor therapy for lymphoma is often associated with cardio- and vasculotoxicity, studying of which is a relevant scientific direction. Markers for myocardial direct injury and dysfunction and ED indexes were studied in patients with indolent lymphomas receiving polychemotherapy (PCT). The study included 77 patients with newly diagnosed indolent type lymphoma. The main group (n=52): mean age, 63.4±2.8 years, 15 (28.8 %) men who had received one course of PCT. The comparison group (n=25): mean age, 61.8±3.7 years, 8 (32 %) men who had not received PCT. Troponin I (TnI), high-sensitivity troponin I (hs-сTnI), heart-type fatty acid binding protein (h-FAВР), and N-terminal pro-B-type natriuretic peptide (NT-prоBNP) were measured in patients of both groups. ED was evaluated by measuring the level of vascular cell adhesion molecule (VCAM) and by assessing the structure and function condition of small blood vessels using photoplethysmography. In both groups, the study parameters were determined at the start of the study (T1) and following the PCT course in the main group; if the PCT schedule included anthracycline antibiotics, the second point (T2) was assessed at 6 h following the drug administration.Results In both groups, the level of NT-proBNP was increased. This increase was significantly more pronounced in the comparison group (49.896±23.228 vs 20.877±8.534 pmol/l, respectively, p=0.011) whereas a tendency to its increase was observed after the PCT course. Before the start of the treatment, laboratory and instrumental signs of ED were noticed: the level of VCAM was 4951±1297 and 3225±757 ng/ml in the comparison group and the main group, respectively (р=0.246); reflection index was &lt;1.8 in 23 (44.2%) patients of the main group and in 16 (64%) patients of the comparison group (р=0.098). During the PTC course, the endothelial function significantly improved; the level of VCAM decreased by 748 ng/ml (p=0.016), which was associated with significant decreases in erythrocyte sedimentation rate by 2.71 mm/h (р=0.027) and lactate dehydrogenase level by 62.38 U/l (р=0.026). Statistically significant decreases in other inflammatory markers (alpha-2-globulin, fibrinogen, C-reactive protein, neutrophil count) were not observed.Conclusion      The level of NT-proBNP showed the highest sensitivity in assessing the cardiotoxic effect of PCT. The dynamics of VCAM level suggested a possible role of the disease itself in the development of ED in this patient group.

Follow-Up Functional Class and 6-Minute Walk Distance Identify Long-Term Survival in Pulmonary Arterial Hypertension

PURPOSE

Guidelines recommend specific treatment goals for pulmonary arterial hypertension (PAH) patients: functional class I or II, 6-min walk distance (6MWD) ≥ 380 to 440 m, normal natriuretic peptide levels, and normal right-sided invasive hemodynamics. Only observational registry data support this recommendation. Our aim was to test these goals in a large group 1 PAH cohort against long-term survival.

METHODS

We analyzed the PHIRST and TRIUMPH populations (n = 563, age 53.5 ± 14.7 years, female sex 79%). The predictor variables were the treatment goals measured at the end of the placebo-controlled phase (16 and 12 weeks, respectively). The primary outcome was all-cause mortality at the end of follow-up during the open-label extension phase.

RESULTS

There were 73 deaths during median follow of 1072 days (range 27 to 2177). Patients who achieved a functional class I or II had better survival. Both a 6MWD ≥ 380 m and ≥ 440 m were associated with lower mortality, but survival was better in patients able to walk ≥ 440 m. The best long-term survival was achieved with functional class I or II and 6MWD ≥ 440 m. In a subset of the population, cardiac index > 2.5 L/min/m² was weakly associated with better survival.

CONCLUSION

WHO functional class I or II, 6MWD ≥ 440 m and CI > 2.5 L/min/m² measured 12-16 weeks after the introduction of PAH-targeted therapy are associated with better long-term survival in PAH. Best survival is observed by reaching both the functional class and the 6MWD goals.

Pediatric Pulmonary Arterial Hypertension

Pulmonary hypertension (PH), the syndrome of increased pressure in the pulmonary arteries, is associated with significant morbidity and mortality for affected children and is associated with a variety of potential underlying causes. Several pulmonary arterial hypertension-targeted therapies have become available to reduce pulmonary artery pressure and improve outcome, but there is still no cure for most patients. This review provides a description of select causes of PH encountered in pediatrics and an update on the most recent data pertaining to evaluation and management of children with PH. Available evidence for specific classes of PH-targeted therapies in pediatrics is discussed.

Nitric Oxide Stroke Volume Index as a New Hemodynamic Prognostic Parameter for Patients with Pulmonary Arterial Hypertension

The aim of the study was to determine the prognostic value of hemodynamic parameters measured during initial diagnostic right heart catheterization (RHC) in standard conditions and using a nitric oxide reversibility test. A retrospective observational study of 62 patients with pulmonary arterial hypertension (PAH) was performed. Clinical, biochemical, echocardiographic, and hemodynamic data obtained at the time of the PAH diagnosis were precisely analyzed. Patients were followed for five years. Death or lung transplantation was considered as a primary endpoint. The mean follow-up period was 1090 ± 703 days and the median age was 46.84 years. In the studied group, 25 patients survived, 36 patients died, and one underwent a lung transplantation. From all the examined parameters, only stroke volume index during reversibility test with iNO (SVI_{(NO test)}) (HR = 0.910; 95% confidence interval 0.878–0.944; p < 0.001) and initial arterial oxygen saturation (SaO₂) (HR = 0.910; 95% confidence interval 0.843–0.982; p = 0.015) have been established as independent predictors of death or lung transplantation in the five-year follow–up. An SVI_{(NO test)} value above 39.86 mL/m² was associated with 100% five-year survival rate (AUC = 0.956; 95% confidence interval 0.899–1.000; p < 0.001; specificity/sensitivity: 100/84%). The results of the analysis suggest that the SVI_{(NO test)} measured during the initial diagnostic RHC could be a very valuable prognostic factor in the PAH patients.

Pulmonary hypertension: Proteins in the blood

The plasma proteome is rich in information. It comprises proteins that are secreted or lost from cells as they respond to their local environment. Changes in the constitution of the plasma proteome offer a relatively non-invasive report on the health of tissues. This is particularly true of the lung in pulmonary hypertension, given the large surface area of the pulmonary vasculature in direct communication with blood. So far, this is relatively untapped; we have relied on proteins released from the heart, specifically brain natriuretic peptide and troponin, to inform clinical management. New technology allows the measurement of a larger number of proteins that cover a broad range of molecular pathways in a single small aliquot. The emerging data will yield more than just new biomarkers of pulmonary hypertension for clinical use. Integrated with genomics and with the help of new bioinformatic tools, the plasma proteome can provide insight into the causative drivers of pulmonary vascular disease and guide drug development.

Association of N-Terminal Pro Brain Natriuretic Peptide and Long-Term Outcome in Patients With Pulmonary Arterial Hypertension

BACKGROUND

NT-proBNP (N-terminal pro brain natriuretic peptide) levels are included in the multiparametric risk assessment approach for pulmonary arterial hypertension (PAH) outlined in PAH guidelines. However, data supporting the use of NT-proBNP risk thresholds in assessing prognosis in PAH are limited. The GRIPHON trial (Prostacyclin [PGI₂] Receptor Agonist In Pulmonary Arterial Hypertension) provides an opportunity to assess the prognostic value of NT-proBNP thresholds in a controlled clinical trial and to evaluate the response to selexipag according to these thresholds.

METHODS

The event-driven GRIPHON trial randomly assigned patients to selexipag or placebo. NT-proBNP was measured at regular intervals in GRIPHON. Here, patients were categorized post hoc into low, medium, and high NT-proBNP subgroups according to 2 independent sets of thresholds: (1) baseline tertiles: <271 ng/L; 271 to 1165 ng/L; >1165 ng/L; and (2) 2015 European Society of Cardiology/European Respiratory Society guidelines cutoffs: <300 ng/L; 300 to 1400 ng/L; >1400 ng/L. Hazard ratios (selexipag versus placebo) with 95% CIs were calculated for the primary end point (composite morbidity/mortality events) by NT-proBNP category at baseline using Cox proportional-hazards models, and at any time during the exposure period using a time-dependent Cox model.

RESULTS

With both thresholds, baseline and follow-up NT-proBNP categories were highly prognostic for future morbidity/mortality events during the study ( P<0.0001). In the time-dependent analysis, the risk of experiencing a morbidity/mortality event was 92% and 83% lower in selexipag-treated patients with a low and medium NT-proBNP level, and 90% and 56% lower in placebo-treated patients with a low and medium NT-proBNP level, in comparison with patients with a high NT-proBNP level. Selexipag reduced the risk of morbidity/mortality events across all 3 NT-proBNP categories in both the baseline and time-dependent analyses, with a more pronounced treatment benefit of selexipag seen in the medium and low NT-proBNP subgroups (interaction P values 0.20 and 0.007 in the baseline and time-dependent analyses).

CONCLUSIONS

These analyses further establish the prognostic relevance of NT-proBNP levels in PAH and provide first evidence for the association of NT-proBNP level and treatment response. Using 2 similar sets of thresholds, these analyses support the relevance of the low, medium, and high NT-proBNP categories as part of the multiparametric risk assessment approach outlined in the European Society of Cardiology/European Respiratory Society guidelines for the management of PAH patients.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01106014.

Metabolic syndrome, neurohumoral modulation, and pulmonary arterial hypertension

Pulmonary vascular disease, including pulmonary arterial hypertension (PAH), is increasingly recognized to be affected by systemic alterations including up-regulation of the renin-angiotensin-aldosterone system and perturbations to metabolic pathways, particularly glucose and fat metabolism. There is increasing preclinical and clinical data that each of these pathways can promote pulmonary vascular disease and right heart failure and are not simply disease markers. More recently, trials of therapeutics aimed at neurohormonal activation or metabolic dysfunction are beginning to shed light on how interventions in these pathways may affect patients with PAH. This review will focus on underlying mechanistic data that supports neurohormonal activation and metabolic dysfunction in the pathogenesis of PAH and right heart failure as well as discussing early translational data in patients with PAH.

Demographic and clinical characteristics of pulmonary arterial hypertension caused by schistosomiasis are indistinguishable from other etiologies

INTRODUCTION:

Pulmonary arterial hypertension (PAH) is a serious pulmonary circulation disease caused by several etiologies, including schistosomiasis. The present study retrospectively evaluated the clinical and hemodynamic characteristics of patients with schistosomal PAH (PAH-Sch) compared to those of non-Sch PAH patients (non-Sch PAH).

METHODS:

Patients treated at the Pronto-Socorro Cardiológico de Pernambuco and diagnosed by right cardiac catheterization were divided into PAH-Sch and non-Sch PAH groups. Their socio-demographic and clinical characteristics, N-terminal-pro B-type natriuretic peptide (NT-proBNP), and echocardiography and hemodynamic parameters were retrospectively reviewed.

RESULTS:

Among the included 98 patients (mean age, 45 ± 14 years; 68 women [69.4%]), we found 56 PAH-Sch and 42 non-Sch PAH. The age distribution was heterogeneous in the PAH-Sch group, with patients predominantly ranging from 50-59 (p <0.004). Dyspnea was the most common symptom, reported by 92 patients (93.8%), and commonly present for over two years prior to diagnosis. Clinical symptoms were similar in both groups, with no differences in functional class, pulmonary artery systolic pressure (p = 0.102), 6-minute walk test score (p = 0.234), NT-proBNP serum levels (p = 0.081), or hemodynamic parameters.

CONCLUSIONS:

Patients with PAH-Sch present clinical, laboratory, and hemodynamic profiles similar to those with PAH resulting from other etiologies of poor prognosis. PAH is an important manifestation of schistosomiasis in endemic regions that is often diagnosed late.