Primary pulmonary hypertension: natural history and the importance of thrombosis

Nbeal2 knockout mice are not protected against hypoxia-induced pulmonary vascular remodeling and pulmonary hypertension

ABSTRACT

Inflammation drives the initiation and progression of pulmonary hypertension (PH). Platelets, increasingly recognized as immune cells, are activated and increased in the lungs of patients with PH. Platelet activation leads to the release of α-granule chemokines, many of which are implicated in PH. We hypothesized that hypoxia-induced secretion of platelet α-granule-stored proteins and PH would be prevented in Neurobeachin-like 2 knockout (Nbeal2-/-) α-granule-deficient mice. Wild-type (WT) and Nbeal2-/- mice were maintained in normoxia or exposed to 10% hypobaric hypoxia for 3, 14, 21, or 35 days. We observed macrothrombocytopenia, increased circulating neutrophils and monocytes, and increased lung interstitial macrophages (IMs) in Nbeal2-/- mice at baseline. Hypoxia-induced platelet activation was attenuated, and hypoxia-induced increase in lung platelet factor 4 (PF4) and platelets was delayed in Nbeal2-/- mice compared with in WT mice. Finally, although pulmonary vascular remodeling (PVR) and PH were attenuated at day 21, Nbeal2-/- mice were not protected against hypoxia-induced PVR and PH at day 35. Although this mutation also affected circulating monocytes, neutrophils, and lung IMs, all of which are critical in the development of experimental PH, we gained further support for the role of platelets and α-granule proteins, such as PF4, in PH progression and pathogenesis and made several observations that expand our understanding of α-granule-deficient mice in chronic hypoxia.

Tailoring oral anticoagulant treatment in the era of multi-drug therapies for PAH and CTEPH

The use of oral anticoagulants in the management of pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) presents distinct therapeutic challenges and benefits. In PAH, the benefits of oral anticoagulation are uncertain, with studies yielding mixed results on their efficacy and safety. Conversely, oral anticoagulants are a cornerstone in the treatment of CTEPH, where their use is consistently recommended to prevent recurrent thromboembolic events. The choice between vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs) remains a significant clinical question, as each type presents advantages and potential drawbacks. Furthermore, drug-drug interactions (DDIs) with concomitant PAH and CTEPH treatments complicate anticoagulant management, necessitating careful consideration of individual patient regimens. This review examines the current evidence on oral anticoagulant use in PAH and CTEPH and discusses the implications of DDIs within a context of multi-drug treatments, including targeted drugs in PAH.

The role of anticoagulation on the long-term survival of patients with pulmonary arterial hypertension: A meta-analysis of 15 cohort studies

INTRODUCTION

Anticoagulation was once recommended for patients with pulmonary arterial hypertension (PAH). However, its survival benefit still remained controversial. We performed a meta-analysis to evaluate the effect of anticoagulation on the long-term survival of PAH patients.

METHODS

The PubMed, EMBASE, Web of Science, and WanFang electronic database were searched for eligible studies. Pooled hazard ratios (HRs) with 95 % confidence intervals (CIs) were calculated for effect estimate regarding anticoagulation on the survival of PAH patients.

RESULTS

Fifteen cohort studies involving 4266 PAH patients were included. Approximately 45.8 % patients received anticoagulation. The mean follow-up period ranged from 2.1 to 14 years. Anticoagulation had a tendency to, however, did not significantly reduce mortality of PAH patients (HR: 0.86, 95 % CI: 0.73-1.02). In subgroup analysis, anticoagulation decreased the mortality risk as analyzed from retrospective studies (HR: 0.80, 95 % CI: 0.65-0.98), but not prospective studies (HR: 0.95, 95 % CI: 0.70-1.29). For both idiopathic PAH (IPAH) and connective tissue disease associated PAH (CTD-PAH), anticoagulation therapy did not significantly improve the long-term survival rate (HR: 0.83, 95 % CI: 0.65-1.07, and HR: 1.05, 95 % CI: 0.77-1.42, respectively), and this result remained unchanged when pooling data from either retrospective or prospective studies. Further analysis showed that anticoagulation had no advantage in reducing mortality in patients with systemic sclerosis associated PAH, systemic erythematosus lupus related PAH (free of antiphospholipid syndrome), or CTD-PAH of non-specified etiology.

CONCLUSION

Anticoagulation may not reduce the long-term mortality of PAH patients, including those with IPAH and CTD-PAH. In the management of PAH, anticoagulants should be prescribed with caution before comprehensive risk to benefit evaluation. Larger and more vigorously designed controlled trials are warranted.

A Single Center Experience of Pulmonary Arterial Hypertension Management in Korea: A 25-Year Comparative Analysis Following the Introduction of Targeted Therapy

BACKGROUND AND OBJECTIVES

The transformation of pulmonary arterial hypertension (PAH) treatment in Korea, ushered by targeted therapy's advent, prompted our analysis of baseline attributes, treatment trends, and survival shifts within our single-center registry.

METHODS

We examined 230 patients (72.6% female, mean age 40.6±17.4 years) diagnosed and/or treated between 1980 and 2021 in our PAH clinic. Given targeted therapy's introduction and active use since 2007, we compared diagnostic classification, demographics, and treatment patterns at that juncture. Survival analysis encompassed PAH types and the overall population. For historical survival comparison, 50 non-registry patients were retrospectively added, and age-sex matching enabled pooled analysis.

RESULTS

Congenital heart disease-associated pulmonary arterial hypertension (CHD-PAH) constituted the largest subset (43.0%), trailed by connective tissue disease-associated PAH (CTD-PAH, 29.6%) and idiopathic PAH (IPAH, 19.1%). Post-2007, CTD-PAH proportions surged, notably with an elevated initiation rate of targeted therapy (95.4%). Overall survival rates at 1, 5, and 10 years stood at 91.3%, 77.4%, and 65.8%, respectively, with CHD-PAH exhibiting superior survival to idiopathic or CTD-PAH. Age-sex matching analysis indicated survival disparities between those starting immediate targeted therapy vs. conservative treatment upon diagnosis, especially driven by IPAH.

CONCLUSIONS

In the post-introduction of the targeted therapy era, patients with PAH promptly started treatment right away, and higher survival rates of patients who started initial PAH-targeted therapy were demonstrated. The transition towards early treatment initiation might have likely contributed to the elevated survival rates observed in Korea's PAH patient cohort.

Comparison of different venous access ways for right heart catheterization-a meta-analysis

OBJECTIVES

Right heart catheterization (RHC) is a common diagnostic tool and of special importance in the diagnosis of pulmonary hypertension (PH). Until today, there have been no clear instructions or guidelines on which venous access to prefer. This meta-analysis assessed whether the choice of the venous access site for elective RHC has an impact on procedural or clinical outcomes.

METHODS

A structured literature search was performed. Single-arm reports and controlled trials reporting event data were eligible. The primary endpoint was a composite of access-related and overall complications.

RESULTS

Nineteen studies, including 6509 RHC procedures, were eligible. The results were analyzed in two groups. The first group compared central venous access (CVA; n = 2072) with peripheral venous access (PVA; n = 2680) and included only multi-arm studies (n = 12, C/P comparison). In the second group, all studies (n = 19, threeway comparison) were assessed to compare the three individual access ways. The overall complication rate was low at 1.0% (n = 68). The primary endpoint in the C/P comparison occurred significantly less for PVA than for CVA (0.1% vs. 1.2%; p = 0.004). In the threeway comparison, PVA had a significantly lower complication rate than femoral access (0.3% vs. 1.1%; p = 0.04). Jugular access had the numerically highest complication rate (2.0%), but the difference was not significant compared to peripheral (0.3%; p = 0.29) or femoral access (1.1%; p = 0.32).

CONCLUSION

This meta-analysis showed that PVA for RHC has a significantly lower complication rate than CVA. There was a low level of certainty and high heterogeneity. This pooled data analysis indicated PVA as the primary venous access for RHC.

Platelet hyperresponsiveness and increased platelet-neutrophil aggregates in dogs with myxomatous mitral valve disease and pulmonary hypertension

BACKGROUND

Pulmonary hypertension (PH) in dogs with myxomatous mitral valve disease (MMVD) is caused by increased pulmonary venous pressure. Thrombosis, vascular remodeling, and vasoconstriction mediated by platelets could exacerbate PH.

HYPOTHESIS

Dogs with PH will exhibit a hypercoagulable state, characterized by increased platelet activation, platelet-leukocyte, and platelet-neutrophil aggregate formation.

ANIMALS

Eleven dogs (≥3.5 kg) diagnosed with MMVD and PH and 10 dogs with MMVD lacking PH.

METHODS

Prospective cohort ex vivo study. All dogs underwent echocardiographic examination, CBC, 3-view thoracic radiographs, and heartworm antigen testing. Severity of PH and MMVD were assessed by echocardiography. Viscoelastic monitoring of coagulation was assessed using thromboelastography (TEG). Platelet activation and platelet-leukocyte/platelet-neutrophil interactions were assessed using flow cytometry. Plasma serotonin concentrations were measured by ELISA.

RESULTS

Unstimulated platelets from dogs with MMVD and PH expressed more surface P-selectin than MMVD controls (P = .03). Platelets from dogs with MMVD and PH had persistent activation in response to agonists. The number of platelet-leukocyte aggregates was higher in dogs with MMVD and PH compared with MMVD controls (P = .01). Ex vivo stimulation of whole blood resulted in higher numbers of platelet-neutrophil aggregates in dogs with MMVD and PH (P = .01). Assessment of hypercoagulability based on TEG or plasma serotonin concentrations did not differ between groups.

CONCLUSION AND CLINICAL IMPORTANCE

Platelet hyperresponsiveness and increased platelet-neutrophil interaction occur in dogs with MMVD and PH, suggesting that platelets play a role of in the pathogenesis of PH. Clinical benefits of antiplatelet drugs in dogs with MMVD and PH require further investigation.

The Early Detection of Pulmonary Hypertension

BACKGROUND

Up to 1% of the world population and 10% of all persons over age 65 suffer from pulmonary hypertension (PH). The latency from the first symptom to the diagnosis is more than one year on average, and more than three years in 20% of patients. 40% seek help from more than four different physicians until their condition is finally diagnosed.

METHODS

This review is based on publications retrieved by a selective literature search on pulmonary hypertension.

RESULTS

The most common causes of pulmonary hypertension are left heart diseases and lung diseases. Its cardinal symptom is exertional dyspnea that worsens as the disease progresses. Additional symptoms of right heart failure are seen in advanced stages. Pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) are rare, difficult to diagnose, and of particular clinical relevance because specific treatments are available. For this reason, strategies for the early detection of PAH and CTEPH have been developed. The clinical suspicion of PH arises in a patient who has nonspecific symptoms, electrocardiographic changes, and an abnormal (NT-pro-)BNP concentration. Once the suspicion of PH has been confirmed by echocardiography and, if necessary, differential-diagnostic evaluation with a cardiopulmonary stress test, and after the exclusion of a primary left heart disease or lung disease, the patient should be referred to a PH center for further diagnostic assessment, classification, and treatment.

CONCLUSION

If both the (NT-pro-)BNP and the ECG are normal, PH is unlikely. Knowledge of the characteristic clinical manifestations and test results of PH is needed so that patients can be properly selected for referral to specialists and experts in PH.

Management of Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a rare pulmonary vascular disease characterized by progressive pulmonary arterial remodeling, increased pulmonary vascular resistance, right ventricular dysfunction, and reduced survival. Effective therapies have been developed that target three pathobiologic pathways in PAH: nitric oxide, endothelin-1, and prostacyclin. Approved therapies for PAH include phosphodiesterase type-5 inhibitors, soluble guanylate cyclase stimulators, endothelin receptor antagonists, prostacyclin analogs, and prostacyclin receptor agonists. Management of PAH in the modern era incorporates multidimensional risk assessment to guide the use of these medications. For patients with PAH and without significant comorbidities, current guidelines recommend two oral medications (phosphodiesterase type-5 inhibitor and endothelin receptor antagonist) for low- and intermediate-risk patients, with triple therapy including a parenteral prostacyclin to be considered in those at high or intermediate-high risk. Combination therapy may be poorly tolerated and less effective in patients with PAH and cardiopulmonary comorbidities. Thus, a single-agent approach with individualized decisions to add-on other PAH therapies is recommended in older patients and those with significant comorbid conditions. Management of PAH is best performed in multidisciplinary teams located in experienced centers. Other core pillars of PAH management include supportive and adjunctive treatments including oxygen, diuretics, rehabilitation, and anticoagulation in certain patients. Patients with PAH who progress despite optimal treatment or who are refractory to best medical care should be referred for lung transplantation, if eligible. Despite considerable progress, PAH is often fatal and new therapies that reverse the disease and improve outcomes are desperately needed.

Pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a rare and progressive disease characterised by remodelling of the pulmonary arteries and progressive narrowing of the pulmonary vasculature. This leads to a progressive increase in pulmonary vascular resistance and pulmonary arterial pressure and, if left untreated, to right ventricular failure and death. A correct diagnosis requires a complete work-up including right heart catheterisation performed in a specialised centre. Although our knowledge of the epidemiology, pathology and pathophysiology of the disease, as well as the development of innovative therapies, has progressed in recent decades, PAH remains a serious clinical condition. Current treatments for the disease target the three specific pathways of endothelial dysfunction that characterise PAH: the endothelin, nitric oxide and prostacyclin pathways. The current treatment algorithm is based on the assessment of severity using a multiparametric risk stratification approach at the time of diagnosis (baseline) and at regular follow-up visits. It recommends the initiation of combination therapy in PAH patients without cardiopulmonary comorbidities. The choice of therapy (dual or triple) depends on the initial severity of the condition. The main treatment goal is to achieve low-risk status. Further escalation of treatment is required if low-risk status is not achieved at subsequent follow-up assessments. In the most severe patients, who are already on maximal medical therapy, lung transplantation may be indicated. Recent advances in understanding the pathophysiology of the disease have led to the development of promising emerging therapies targeting dysfunctional pathways beyond endothelial dysfunction, including the TGF-β and PDGF pathways.

Medical Management of Pulmonary Arterial Hypertension: Current Approaches and Investigational Drugs

Pulmonary arterial hypertension (PAH) is a malignant pulmonary vascular syndrome characterized by a progressive increase in pulmonary vascular resistance and pulmonary arterial pressure, which eventually leads to right heart failure and even death. Although the exact mechanism of PAH is not fully understood, pulmonary vasoconstriction, vascular remodeling, immune and inflammatory responses, and thrombosis are thought to be involved in the development and progression of PAH. In the era of non-targeted agents, PAH had a very dismal prognosis with a median survival time of only 2.8 years. With the deep understanding of the pathophysiological mechanism of PAH as well as advances in drug research, PAH-specific therapeutic drugs have developed rapidly in the past 30 years, but they primarily focus on the three classical signaling pathways, namely the endothelin pathway, nitric oxide pathway, and prostacyclin pathway. These drugs dramatically improved pulmonary hemodynamics, cardiac function, exercise tolerance, quality of life, and prognosis in PAH patients, but could only reduce pulmonary arterial pressure and right ventricular afterload to a limited extent. Current targeted agents delay the progression of PAH but cannot fundamentally reverse pulmonary vascular remodeling. Through unremitting efforts, new therapeutic drugs such as sotatercept have emerged, injecting new vitality into this field. This review comprehensively summarizes the general treatments for PAH, including inotropes and vasopressors, diuretics, anticoagulants, general vasodilators, and anemia management. Additionally, this review elaborates the pharmacological properties and recent research progress of twelve specific drugs targeting three classical signaling pathways, as well as dual-, sequential triple-, and initial triple-therapy strategies based on the aforementioned targeted agents. More crucially, the search for novel therapeutic targets for PAH has never stopped, with great progress in recent years, and this review outlines the potential PAH therapeutic agents currently in the exploratory stage to provide new directions for the treatment of PAH and improve the long-term prognosis of PAH patients.

Electrocardiogram in patients with pulmonary hypertension

INTRODUCTION

Pulmonary hypertension (PH) is a potentially life-threatening cardiovascular disease defined by a mean pulmonary arterial pressure (mPAP) > 20 mmHg. Due to non-specific symptoms, PH is often diagnosed late and at advanced stage. In addition to other diagnostic modalities, the electrocardiogram (ECG) can help in establishing the diagnosis. Knowledge of typical ECG signs could help to detect PH earlier.

METHODS

A non-systematic literature review on the typical electrocardiographic patterns of PH was performed.

RESULTS

Characteristic signs of PH include right axis deviation, SIQIIITIII and SISIISIII patterns, P pulmonale, right bundle branch block, deep R waves in V1 and V2, deep S waves in V5 and V6, and right ventricular hypertrophy (R in V1 + S in V5, V6 > 1,05 mV). Repolarisation abnormalities such as ST segment depressions or T wave inversions in leads II, III, aVF, and V1 to V3 are common as well. Furthermore, a prolonged QT/QTc interval, an increased heart rate, or supraventricular tachyarrhythmias can be observed. Some parameters may even provide information about the patient's prognosis.

CONCLUSION

Not every PH patient shows electrocardiographic PH signs, especially in mild PH. Thus, the ECG is not useful to completely rule out PH, but provides important clues to PH when symptoms are present. The combination of typical ECG signs and the co-occurrence of electrocardiographic signs with clinical symptoms and elevated BNP levels are particularly suspicious. Diagnosing PH earlier could prevent further right heart strain and improve patient prognosis.

Liver stiffness assessed by magnetic resonance elastography predicts clinical outcomes in patients with heart failure and without chronic liver disease

OBJECTIVES

Evaluation of liver stiffness (LS) by magnetic resonance elastography (MRE) is useful for estimating right atrial pressure (RAP) in patients with heart failure (HF). However, its prognostic implications are unclear. We sought to investigate whether LS measured by MRE (LS-MRE) could predict clinical outcomes in patients with HF.

METHODS

We prospectively examined 207 consecutive HF patients between April 2018 and May 2021 after excluding those with organic liver disease. All patients underwent 3.0-T MRE. The primary outcome of interest was the composite of all-cause death and hospitalisation for HF.

RESULTS

During a median follow-up period of 720 (interquartile range [IQR] 434-1013) days, the primary outcome occurred in 44 patients (21%), including 15 (7%) all-cause deaths and 29 (14%) hospitalisations for HF. The patients were divided into two groups according to median LS-MRE of 2.54 (IQR 2.34-2.82) kPa. Patients with higher LS-MRE showed a higher incidence of the primary outcome compared to those with lower LS-MRE (p < 0.001). Multivariable Cox regression analyses revealed that LS-MRE value was independently associated with the risk of adverse events (hazard ratio 2.49, 95% confidence interval 1.46-4.24). In multivariable linear regression, RAP showed a stronger correlation with LS-MRE (β coefficient = 0.31, p < 0.001) compared to markers related to liver fibrosis.

CONCLUSIONS

In patients without chronic liver disease and presenting with HF, elevated LS-MRE was independently associated with worse clinical outcomes. Elevated LS-MRE may be useful for risk stratification in patients with HF and without chronic liver disease.

KEY POINTS

• Magnetic resonance elastography (MRE) is an emerging non-invasive imaging technique for evaluating liver stiffness (LS) which can estimate right atrial pressure. • Elevated LS-MRE, which mainly reflects liver congestion, was independently associated with worse clinical outcomes in patients with heart failure. • The assessment of LS-MRE would be useful for stratifying the risk of adverse events in heart failure patients without chronic liver disease.

Anticoagulation in pulmonary arterial hypertension - association with mortality, healthcare utilization, and quality of life: The Pulmonary Hypertension Association Registry (PHAR)

BACKGROUND

Routine long-term anticoagulation in pulmonary arterial hypertension (PAH) is controversial. To date, anticoagulation has been found to be beneficial or neutral in idiopathic disease (IPAH) and neutral-to-harmful in connective tissue disease (CTD-PAH). We sought to examine the association between anticoagulation and mortality, healthcare utilization, and quality of life (QoL) in PAH.

METHODS

The PHAR is a prospective registry of PAH patients referred to 58 pulmonary hypertension care centers in the United States. We compared patients who received anticoagulation during enrollment (questionnaire documented) to those who did not. Cox proportional hazard models were used for mortality, Poisson multivariate regression models for healthcare utilization, and generalized estimating equations for QOL RESULTS: Of 1175 patients included, 316 patients were treated with anticoagulation. IPAH/hereditary PAH (HPAH) comprised 46% of the cohort and CTD-PAH comprised 33%. After adjustment for demographics, clinical characteristics, site and disease severity, anticoagulation was not associated with mortality in the overall population (HR, 1.00; 95% CI, 0.72-1.36), IPAH/HPAH (HR, 1.19; 95% CI, 0.74-1.94), or CTD-PAH (HR 0.87; 95% CI, 0.53-1.42). Anticoagulation was associated with an increased rate of emergency department visits (IRR: 1.41), hospitalizations (IRR: 1.30), and hospital days (IRR 1.33). QOL measured by emPHasis-10 score was worse in patients receiving anticoagulation (mean difference 1.74; 95% CI 0.40-3.09).

CONCLUSIONS

Anticoagulation is not associated with higher mortality, but is associated with increased healthcare utilization in the PHAR. PAH-specific QoL may be worse in patients receiving anticoagulation. The risks and benefits surrounding routine prescription of anticoagulation for PAH should be carefully considered.

Role of solid lipid nanoparticle for the delivery of Lipophilic Drugs and Herbal Medicines in the treatment of pulmonary hypertension

Pulmonary arterial hypertension (PAH) is an uncommon condition marked by elevated pulmonary artery pressure that leads to right ventricular failure. The majority of drugs are now been approved by FDA for PAH, however, several biopharmaceutical hindrances lead to failure of the therapy. Various novel drug delivery systems are available in the literature from which lipid-based nanoparticles i.e. solid lipid nanoparticle is widely investigated for improving the solubility and bioavailability of drugs. In this paper, the prototype phytoconstituents used in pulmonary arterial hypertension have limited solubility and bioavailability. We highlighted the novel concepts of SLN for lipophilic phytoconstituents with their potential applications. This paper also reviews the present state of the art regarding production techniques for SLN like High-Pressure Homogenization, Micro-emulsion Technique, and Phase Inversion Temperature Method, etc. Furthermore, toxicity aspects and in vivo fate of SLN are also highlighted in this review. In a nutshell, safer delivery of phytoconstituents by SLN added a novel feather to the cap of successful drug delivery technologies.

Pregnancy in Pulmonary Arterial Hypertension: A Multidisciplinary Approach

Pulmonary arterial hypertension (PAH), a female predominant disease, carries a high maternal and fetal mortality in pregnancy despite improved insight and the development of novel therapies. The high risk is attributed to the adaptive changes that take place to promote healthy fetal development during pregnancy, which can adversely affect the already compromised right ventricle in patients with PAH. While in the prior era emphasis was placed on termination of pregnancy, here we will illustrate through a multidisciplinary approach and meticulous planning at an expert center, these high-risk women can undergo successful childbirth.

The Potential Application and Promising Role of Targeted Therapy in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a rare yet serious progressive disorder that is currently incurable. This female-predominant disease unfolds as a pan-vasculopathy that affects all layers of the vessel wall. Five classes of pharmacological agents currently exist to target the three major cellular signaling pathways identified in PAH but are incapable of effectively reversing the disease progression. While several targets have been identified for therapy, none of the current PAH specific therapies are curative and cost-effective as they fail to reverse vascular remodeling and do not address the cancer-like features of PAH. Our purpose is to review the current literature on the therapeutic management of PAH, as well as the molecular targets under consideration for therapy so as to shed light on the potential role and future promise of novel strategies in treating this high-mortality disease. This review study summarizes and discusses the potential therapeutic targets to be employed against PAH. In addition to the three major conventional pathways already used in PAH therapy, targeting PDGF/PDGFR signaling, regulators in glycolytic metabolism, PI3K/AKT pathways, mitochondrial heat shock protein 90 (HSP90), high-mobility group box-1 (HMGB1), and bromodomain and extra-terminal (BET) proteins by using their specific inhibitors, or a pharmacological induction of the p53 expression, could be attractive strategies for treating PAH.

Off-Label Use and Inappropriate Dosing of Direct Oral Anticoagulants in Cardiopulmonary Disease

Direct oral anticoagulants (DOACs) are increasingly used in clinical practice and have become essential in the management of atrial fibrillation and VTE. The enthusiasm for DOACs has fueled the off-label application of these agents in cardiopulmonary disease, and their use has often outpaced the evidence supporting their application. This article reviews the evidence and current off-label use of DOACs in various cardiopulmonary disease states.

Update on the Treatment of Pulmonary Arterial Hypertension

In the last decades, important advances have been made in the treatment of pulmonary arterial hypertension (PAH), a severe, progressive, incurable, and potentially fatal disease. For an adequate therapy, correct hemodynamic diagnosis and etiology classification are fundamental. Many etiologies - rheumatic disease, portal hypertension, congenital heart diseases, schistosomiasis - require specific measures, in addition to drug therapy for PAH. The specific therapy for PAH is based on medications that act on three pathophysiological pathways - prostacyclin, endothelin, and nitric oxide pathways. These drugs have multiple presentations (oral, intravenous, subcutaneous, and inhaled) and have changed the history of PAH. This review presents an overview of drug therapy strategies and different forms and peculiarities of PAH.

Long term prognosis in patients with pulmonary hypertension undergoing catheter ablation for supraventricular tachycardia

Various forms of supraventricular tachycardia (SVT) occur in patients with severe pulmonary hypertension (PH). Despite the high efficacy of radiofrequency catheter ablation (RFCA) for SVT, insufficient data exist regarding patients with PH. Thirty SVTs in 23 PH patients (age 47 [35–60] years; mean pulmonary artery pressure 44 [32–50] mmHg) were analyzed. Procedural success rate, short- and long-term clinical outcomes, were evaluated during a median follow-up of 5.1 years. Single-procedure success rate was 83%; 94% (17/18) in typical atrial flutter, 73% (8/11) in atrial tachycardia (AT), and 100% (1/1) in atrioventricular nodal reentrant tachycardia. Antiarrhythmic drugs, serum brain natriuretic peptide levels and number of hospitalizations significantly decreased after RFCA than that before (p = 0.002, 0.04, and 0.002, respectively). Four patients had several procedures. After last RFCA, 12 patients had SVT and 8 patients died. Kaplan–Meier curves showed that patients with SVT after the last RFCA had a lower survival rate compared to those without (p = 0.0297). Multivariate analysis identified any SVT after the last RFCA as significant risk factor of mortality (hazard ratio: 9.31; p = 0.016). RFCA for SVT in patients with PH is feasible and effective in the short-term, but SVT is common during long-term follow-up and associated with lower survival.

Platelets, extracellular vesicles and coagulation in pulmonary arterial hypertension

Pulmonary arterial hypertension is a rare disease of the pulmonary vasculature, characterised pathologically by proliferation, remodelling and thrombosis in situ. Unfortunately, existing therapeutic interventions do not reverse these findings and the disease continues to result in significant morbidity and premature mortality. A number of haematological derangements have been described in pulmonary arterial hypertension which may provide insights into the pathobiology of the disease and opportunities to explore new therapeutic pathways. These include quantitative and qualitative platelet abnormalities, such as thrombocytopaenia, increased mean platelet volume and altered platelet bioenergetics. Furthermore, a hypercoagulable state and aberrant negative regulatory pathways can be observed, which could contribute to thrombosis in situ in distal pulmonary arteries and arterioles. Finally, there is increasing interest in the role of extracellular vesicle autocrine and paracrine signalling in pulmonary arterial hypertension, and their potential utility as biomarkers and novel therapeutic targets. This review focuses on the potential role of platelets, extracellular vesicles and coagulation pathways in the pathobiology of pulmonary arterial hypertension. We highlight important unanswered clinical questions and the implications of these observations for future research and pulmonary arterial hypertension-directed therapies.

Pulmonary arterial hypertension patients display normal kinetics of clot formation using thrombelastography

Pulmonary arterial hypertension is characterized by endothelial dysfunction and microthrombi formation. The role of anticoagulation remains controversial, with studies demonstrating inconsistent effects on pulmonary arterial hypertension mortality. Clinical anticoagulation practices are currently heterogeneous, reflecting physician preference. This study uses thrombelastography and hematology markers to evaluate whether clot formation and fibrinolysis are abnormal in pulmonary arterial hypertension patients. Venous blood was collected from healthy volunteers (n = 20) and patients with pulmonary arterial hypertension (n = 20) on stable medical therapy for thrombelastography analysis. Individual thrombelastography parameters and a calculated coagulation index were used for comparison. In addition, hematologic markers, including fibrinogen, factor VIII activity, von Willebrand factor activity, von Willebrand factor antigen, and alpha2-antiplasmin, were measured in pulmonary arterial hypertension patients and compared to healthy volunteers. Between group differences were analyzed using t tests and linear mixed models, accounting for repeated measures when applicable. Although the degree of fibrinolysis (LY30) was significantly lower in pulmonary arterial hypertension patients compared to healthy volunteers (0.3% ± 0.6 versus 1.3% ± 1.1, p = 0.04), all values were within the normal reference range (0–8%). All other thrombelastography parameters were not significantly different between pulmonary arterial hypertension patients and healthy volunteers (p ≥ 0.15 for all). Similarly, alpha2-antiplasmin activity levels were higher in pulmonary arterial hypertension patients compared to healthy volunteers (103.7% ± 13.6 versus 82.6% ± 9.5, p < 0.0001), but all individual values were within the normal range (75–132%). There were no other significant differences in hematologic markers between pulmonary arterial hypertension patients and healthy volunteers (p ≥ 0.07 for all). Sub-group analysis comparing thrombelastography results in patients treated with or without prostacyclin pathway targeted therapies were also non-significant. In conclusion, treated pulmonary arterial hypertension patients do not demonstrate abnormal clotting kinetics or fibrinolysis by thrombelastography.

Association Between Anticoagulation Outcomes and Venous Thromboembolism History in Chronic Thromboembolic Pulmonary Hypertension

Background: The association between anticoagulation outcomes and prior history of venous thromboembolism (VTE) in chronic thromboembolic pulmonary hypertension (CTEPH) has not been established. This study aimed to compare the efficacy and safety of anticoagulation treatment in CTEPH patients with and without prior history of VTE.

Methods: A total of 333 CTEPH patients prescribed anticoagulants were retrospectively included from May 2013 to April 2019. The clinical characteristics were collected at their first admission. Incidental recurrent VTE and clinically relevant bleeding were recorded during follow-up. The Cox proportional regression models were used to identify potential factors associated with recurrent VTE and clinically relevant bleeding.

Results: Seventy patients (21%) without a prior history of VTE did not experience recurrent VTE during anticoagulation. Compared to CTEPH patients without a prior history of VTE, those with a prior history of VTE had an increased risk of recurrent VTE [2.27/100 person-year vs. 0/100 person-year; hazard ratio (HR), 8.92; 95% confidence interval (CI), 1.18–1142.00; P = 0.029] but a similar risk of clinically relevant bleeding (3.90/100 person-year vs. 4.59/100 person-year; HR, 0.83; 95% CI, 0.38–1.78; P = 0.623). Multivariate Cox analyses suggested that a prior history of VTE and interruption of anticoagulation treatments were significantly associated with an increased risk of recurrent VTE, while anemia and glucocorticoid use were significantly associated with a higher risk of clinically relevant bleeding.

Conclusions: This study is the first to reveal that a prior history of VTE significantly increases the risk of recurrent VTE in CTEPH patients during anticoagulation treatment. This finding should be further evaluated in prospective studies.

Perioperative Management of Pulmonary Hypertension. a Review

Pulmonary hypertension is a rare and progressive pathology defined by abnormally high pulmonary artery pressure mediated by a diverse range of aetiologies. It affects up to twenty-six individuals per one million patients currently living in the United Kingdom (UK), with a median life expectancy of 2.8 years in idiopathic pulmonary hypertension. The diagnosis of pulmonary hypertension is often delayed due to the presentation of non-specific symptoms, leading to a delay in referral to specialists services. The complexity of treatment necessitates a multidisciplinary approach, underpinned by a diverse disease aetiology from managing the underlying disease process to novel specialist treatments. This has led to the formation of dedicated specialist treatment centres within centralised UK cities. The article aimed to provide a concise overview of pulmonary hypertension's clinical perioperative management, including key definitions, epidemiology, pathophysiology, and risk stratification.

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

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

Anticoagulation in Pulmonary Arterial Hypertension: Do We Know the Answer?

The shear stress and hypoxia in the pulmonary artery in patients with pulmonary arterial hypertension(PAH) causes endothelial dysfunction, smooth muscle proliferation and activation of thrombotic pathways leading to in situ thrombosis. Targeting the thrombotic pathways is a proposed mechanism to slow disease progression and improve survival. Over the years, the survival in patients with PAH has improved due to multiple factors with the increased use of anticoagulation as one of them. Both European Respiratory Society/European Society of Cardiology and American College of Cardiology/American Heart Association guidelines make grade II recommendations for using anticoagulation in PAH. The guidelines are based on weak observational studies with high risk of bias which have only studied warfarin as the choice of anticoagulation. In this article, we review the pathophysiology, rationale and the current literature investigating the role of anticoagulation in PAH.

Endothelial Dysfunction in Pulmonary Hypertension: Cause or Consequence?

Pulmonary arterial hypertension (PAH) is a rare, complex, and progressive disease that is characterized by the abnormal remodeling of the pulmonary arteries that leads to right ventricular failure and death. Although our understanding of the causes for abnormal vascular remodeling in PAH is limited, accumulating evidence indicates that endothelial cell (EC) dysfunction is one of the first triggers initiating this process. EC dysfunction leads to the activation of several cellular signalling pathways in the endothelium, resulting in the uncontrolled proliferation of ECs, pulmonary artery smooth muscle cells, and fibroblasts, and eventually leads to vascular remodelling and the occlusion of the pulmonary blood vessels. Other factors that are related to EC dysfunction in PAH are an increase in endothelial to mesenchymal transition, inflammation, apoptosis, and thrombus formation. In this review, we outline the latest advances on the role of EC dysfunction in PAH and other forms of pulmonary hypertension. We also elaborate on the molecular signals that orchestrate EC dysfunction in PAH. Understanding the role and mechanisms of EC dysfunction will unravel the therapeutic potential of targeting this process in PAH.

Pulmonary Hypertension in Pregnancy

Pulmonary hypertension in pregnancy carries a high maternal and fetal morbidity, and mortality. In recent times, there has been significant progress in the field of pulmonary vascular disease with a better understanding of the disease and novel targeted therapies, which have ultimately resulted in improved outcomes. In addition, the development of an individualized and multidisciplinary approach to the management of pulmonary hypertension during pregnancy is essential for improved outcomes.

Coagulation Profiles of Pulmonary Arterial Hypertension Patients, Assessed by Non-Conventional Hemostatic Tests and Markers of Platelet Activation and Endothelial Dysfunction

Many pathophysiologic processes of pulmonary arterial hypertension (PAH), namely, excess vasoconstriction, vascular remodeling and in situ thrombosis, involve the coagulation cascade, and more specifically, platelets. The aim of this study was to globally assess coagulation processes in PAH, by using non-conventional hemostatic tests, along with markers of platelet activation and endothelial dysfunction. We studied 44 new PAH patients (22 with idiopathic PAH and 22 with connective tissue disease) and 25 healthy controls. The following tests were performed: platelet function analyzer-100 (PFA-100), light transmission aggregometry (LTA), rotational thromboelastometry (ROTEM), endogenous thrombin potential (ETP), serotonin, thromboxane A2 and p-selectin plasma levels, and von Willebrand antigen (VWF:Ag) and activity (VWF:Ac). Our results showed that PAH patients had diminished platelet aggregation, presence of disaggregation, defective initiation of the clotting process and clot propagation, and diminished thrombin formation capacity. Serotonin, thromboxane A2 and p-selectin levels were increased, and VWF:Ag and VWF:Ac decreased in the same population. The results of this study suggest that the platelets of PAH patients are activated and present functional abnormalities. The procoagulant activity, in general, appears to be impaired probably due to a sustained and prolonged activation of the procoagulant processes. Larger observational studies are warranted to confirm these laboratory findings.

Can anticoagulants improve the survival rate for patients with idiopathic pulmonary arterial hypertension? A systematic review and meta-analysis

BACKGROUND

Anticoagulant therapy is believed to be an important component of treatment for idiopathic pulmonary arterial hypertension (IPAH). Recent data suggest that therapy that does not include anticoagulants results in no significant difference in patient survival. We sought to evaluate the effect of anticoagulants on survival in patients with IPAH.

METHODS

A systematic review and a random-effects meta-analysis to estimate hazard ratio (HR) and 95% confidence intervals (CI) were performed. PubMed/MEDLINE, Web of Knowledge and other databases were searched for eligible literature. Review articles and references were also screened.

RESULTS

8 studies with a total of 1812 patients with IPAH were included in this analysis. No randomized controlled trials (RCT) were identified. All the 8 studies had a mean complete follow-up ranging from 3 to 14 years. In this analysis, use of anticoagulants did not significantly decrease mortality risk (P = 0.07, HR = 0.77, 95% CI [0.58, 1.02]). Sensitivity analysis showed similar results (P = 0.12, HR = 0.80, 95% CI [0.60, 1.06]). Subgroup analysis showed that anticoagulants performed no significant advantages with the use of PAH-specific therapies (P = 0.82, HR = 0.95, 95% CI [0.63, 1.44]).

CONCLUSIONS

No randomized evidence to support the use of anticoagulants in IPAH. No significant benefit for patients' survival was found in our analysis. The potential biases of included observational studies made it hard to achieve a meaningful conclusion. The necessity of anticoagulants for IPAH patients remains to be evaluated.

Increased levels of platelet-derived microparticles in pulmonary hypertension

INTRODUCTION

Thrombosis and coagulation abnormalities are thought to be involved in disease progression of pulmonary hypertension. Platelet-derived microparticles (PDMP) are released from platelets following stimulation and have recently been demonstrated to play an important role in pathogenesis of various diseases. This study aimed to evaluate PDMP levels in patients with pulmonary hypertension.

MATERIALS AND METHODS

Our cross-sectional study enrolled a total of 113 participants including 73 patients with pulmonary hypertension and 40 participants to serve as a control group. PDMP levels were measured using a PDMP ELISA kit, which detects glycoproteins CD42a and CD42b. Clinical parameters, including exercise capacity and hemodynamic parameters, were collected, and the relationship to PDMP levels were evaluated.

RESULTS

PDMP levels were significantly higher in patients than in participants in the control group (23.2 ± 39.4 U/mL and 7.8 ± 3.6 U/mL, respectively, P < 0.05). PDMP levels in patients with chronic thromboembolic pulmonary hypertension were correlated with right atrial pressure and cardiac index. PDMP levels were higher in male patients with idiopathic pulmonary arterial hypertension. Furthermore, patients administered a higher dose of epoprostenol had a tendency for lower PDMP levels.

CONCLUSIONS

The data suggest that PDMP levels are increased in patients with pulmonary hypertension. Further study is needed to understand the mechanism and impact of PDMP on disease progression.

Emerging role of cardiovascular magnetic resonance imaging in the management of pulmonary hypertension

Pulmonary hypertension (PH) is a clinical condition characterised by elevation of pulmonary arterial pressure (PAP) above normal range due to various aetiologies. While cardiac right-heart catheterisation (RHC) remains the gold standard and mandatory for establishing the diagnosis of PH, noninvasive imaging of the heart plays a central role in the diagnosis and management of all forms of PH. Although Doppler echocardiography (ECHO) can measure a range of haemodynamic and anatomical variables, it has limited utility for visualisation of the pulmonary artery and, oftentimes, the right ventricle. Cardiovascular magnetic resonance (CMR) provides comprehensive information about the anatomical and functional aspects of the pulmonary artery and right ventricle that are of prognostic significance for assessment of long-term outcomes in disease progression. CMR is suited for serial follow-up of patients with PH due to its noninvasive nature, high sensitivity to changes in anatomical and functional parameters, and high reproducibility. In recent years, there has been growing interest in the use of CMR derived parameters as surrogate endpoints for early-phase PH clinical trials. This review will discuss the role of CMR in the diagnosis and management of PH, including current applications and future developments, in comparison to other existing major imaging modalities.

Gut microbiota modification suppresses the development of pulmonary arterial hypertension in an SU5416/hypoxia rat model

The pathogenesis of pulmonary arterial hypertension is closely associated with dysregulated inflammation. Recently, abnormal alterations in gut microbiome composition and function were reported in a pulmonary arterial hypertension experimental animal model. However, it remains unclear whether these alterations are a result or the cause of pulmonary arterial hypertension. The purpose of this study was to investigate whether alterations in the gut microbiome affected the hemodynamics in SU5416/hypoxia rats. We used the SU5416/hypoxia rat model in our study. SU5416/hypoxia rats were treated with a single SU5416 injection (30 mg/kg) and a three-week hypoxia exposure (10% O2). Three SU5416/hypoxia rats were treated with a combination of four antibiotics (SU5416/hypoxia + ABx group) for four weeks. Another group was exposed to hypoxia (10% O2) without the SU5416 treatment, and control rats received no treatment. Fecal samples were collected from each animal, and the gut microbiota composition was analyzed by 16S rRNA sequencing. The antibiotic treatment significantly suppressed the vascular remodeling, right ventricular hypertrophy, and increase in the right ventricular systolic pressure in SU5416/hypoxia rats. 16S rRNA sequencing analysis revealed gut microbiota modification in SU5416/hypoxia + ABx group. The Firmicutes-to-Bacteroidetes ratio in SU5416/hypoxia rats was significantly higher than that in control and hypoxia rats. Compared with the control microbiota, 14 bacterial genera, including Bacteroides and Akkermansia, increased, whereas seven bacteria, including Rothia and Prevotellaceae, decreased in abundance in SU5416/hypoxia rats. Antibiotic-induced modification of the gut microbiota suppresses the development of pulmonary arterial hypertension. Dysbiosis may play a causal role in the development and progression of pulmonary arterial hypertension.

Pulmonary Arterial Hypertension: A Palliative Medicine Review of the Disease, Its Therapies, and Drug Interactions

Pulmonary arterial hypertension (PAH) is often a progressive and ultimately fatal disease. It is characterized by an elevated mean pulmonary arterial pressure because of disease of the small pulmonary arterioles. PAH leads to a constellation of symptoms, including dyspnea, fatigue, syncope, chest discomfort, and peripheral edema. Disease-targeted therapies for PAH produce symptomatic and functional improvement, but long-term survival remains uncommon without lung transplantation. Palliative care is appropriate to support patients with advanced PAH who typically have a high symptom burden. However, palliative care has historically focused on supporting patients with malignant disease, rather than progressive chronic disease such as PAH. Our aim is to provide palliative care clinicians with a background in the classification, pathophysiology, and modern treatment of PAH. This review describes disease-targeted therapies and their effects on symptoms, physical functioning, and health-related quality of life. We also review the unique physiology of PAH and its implication for palliative interventions. Pharmacological interactions with, and precautions related to commonly used palliative care medications, are discussed.

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.

Assessment of Right Ventricular Function in the Research Setting: Knowledge Gaps and Pathways Forward. An Official American Thoracic Society Research Statement

BACKGROUND

Right ventricular (RV) adaptation to acute and chronic pulmonary hypertensive syndromes is a significant determinant of short- and long-term outcomes. Although remarkable progress has been made in the understanding of RV function and failure since the meeting of the NIH Working Group on Cellular and Molecular Mechanisms of Right Heart Failure in 2005, significant gaps remain at many levels in the understanding of cellular and molecular mechanisms of RV responses to pressure and volume overload, in the validation of diagnostic modalities, and in the development of evidence-based therapies.

METHODS

A multidisciplinary working group of 20 international experts from the American Thoracic Society Assemblies on Pulmonary Circulation and Critical Care, as well as external content experts, reviewed the literature, identified important knowledge gaps, and provided recommendations.

RESULTS

This document reviews the knowledge in the field of RV failure, identifies and prioritizes the most pertinent research gaps, and provides a prioritized pathway for addressing these preclinical and clinical questions. The group identified knowledge gaps and research opportunities in three major topic areas: 1) optimizing the methodology to assess RV function in acute and chronic conditions in preclinical models, human studies, and clinical trials; 2) analyzing advanced RV hemodynamic parameters at rest and in response to exercise; and 3) deciphering the underlying molecular and pathogenic mechanisms of RV function and failure in diverse pulmonary hypertension syndromes.

CONCLUSIONS

This statement provides a roadmap to further advance the state of knowledge, with the ultimate goal of developing RV-targeted therapies for patients with RV failure of any etiology.

Clinical Outcomes and Treatment Options in Patients With Pulmonary Hypertension Who Received Pulmonary Hypertension-Specific Drugs - Single-Center Case Series

Background: Recent progress in the development of pulmonary hypertension (PH)-specific pharmaceutical agents has improved mortality and morbidity remarkably. Today, these PH-specific drugs have become a standard treatment for PH. Methods and Results: We herein summarize the treatment options and longitudinal clinical outcomes of 21 patients with PH who received PH-specific drugs at the present institution. Sixteen patients began treatment with a single PH-specific drug; 9 of them needed additional PH-specific drugs, but the other 7 were still taking the same drug at the last follow-up. Five patients began treatment with a combination of 2 or 3 PH-specific drugs, and their drugs were not discontinued. Most patients (17/21) were taking a phosphodiesterase type 5 (PDE5) inhibitor at the last follow-up. During the 6.5±4.4 years' follow-up, 5 patients died, but only 1 death was related to PH. At 5 and 10 years, the estimated PH-related death-free and lung transplantation-free survival rate was 100% (95% CI: 100-100%) and 87.5% (95% CI: 38.7-98.1%), respectively. The estimated 5- and 10-year estimated overall survival rates were 77.9% (95% CI: 50.8-91.3%) and 68.2% (95% CI: 37.4-86.2%), respectively. Conclusions: PDE5 inhibitors played a central role in the treatment options. The long-term prognosis of PH was favorable at the present institution.

Is Anticoagulation Beneficial in Pulmonary Arterial Hypertension?

Background Data about anticoagulation in pulmonary arterial hypertension (PAH) patients are inconsistent. The objective of this study was to examine the impact of adjunctive oral anticoagulants in patients with PAH through meta-analysis, and to further assess whether response differs by PAH subtype. Methods and Results Cochrane CENTRAL, Medline, and Scopus databases were searched for randomized or nonrandomized studies that assessed the association between anticoagulation and outcomes in patients with PAH. Hazard ratios (HRs) for mortality were pooled using the random effects model. Subgroup analyses were performed for type of PAH and study design. Twelve nonrandomized studies, at moderate risk of bias, were included. These consisted of 2512 patients (1342 receiving anticoagulation and 1170 controls). Anticoagulation significantly reduced mortality in the overall PAH cohort (HR, 0.73 [0.57, 0.93]; P=0.001; I²=64%). On subgroup analysis, a significant mortality reduction was seen in idiopathic PAH patients (HR, 0.73 [0.56, 0.95]; P=0.02; I²=46%), whereas no significant difference was observed in connective tissue disease-related PAH (HR, 1.16 [0.58, 2.32]; P=0.67; I²=71%). Sensitivity analysis specific to scleroderma-associated PAH demonstrated a significant increase in mortality with anticoagulant use (HR, 1.58 [1.08, 2.31]; P=0.02; I²=9%). Conclusions This meta-analysis shows that use of anticoagulation may improve survival in idiopathic PAH patients, while increasing mortality when used in scleroderma-associated-PAH patients. Currently, no randomized clinical trials have been published, and until randomized data are available, anticoagulant use in PAH should be tailored to PAH subtype.

Pulmonary Arterial Hypertension and Therapeutic Interventions

Pulmonary hypertension is an uncommon disease that carries a significant morbidity and mortality. Pulmonary arterial hypertension is a subtype of pulmonary hypertension that describes a group of disease entities that lead to an elevation in precapillary pulmonary artery pressure. Despite advances in the diagnosis and treatment of pulmonary arterial hypertension, it remains a difficult disease to recognize and manage. In this review article, we will discuss the definition and diagnosis of pulmonary arterial hypertension. Additionally, we will discuss the ever-expanding management options, their mechanisms and strategies, including combination therapy and the most recent advances and future directions.

Pulmonary hypertension with a low cardiac index requires a higher PaO2 level to avoid tissue hypoxia

BACKGROUND AND OBJECTIVE

The optimal oxygen supplementation needed to avoid tissue hypoxia in patients with pulmonary hypertension (PH) remains unclear. This study aimed to identify the arterial oxygen tension (PaO₂ ) level needed to avoid tissue hypoxia which results in a poor prognosis in patients with PH.

METHODS

We retrospectively analysed the data for 1571 right heart catheterizations in patients suspected of having PH between 1983 and 2017 at our institution. Examinations were classified according to mean pulmonary arterial pressure (mPAP), cardiac index (CI) and the presence of lung disease, pulmonary arterial hypertension (PAH) or chronic thromboembolic PH (CTEPH). The PaO₂ levels needed to avoid tissue hypoxia were compared in each subgroup.

RESULTS

The estimated PaO₂ equivalent to a mixed venous oxygen tension (PvO₂ ) of 35 mm Hg (tissue hypoxia) was 63.2 mm Hg in all patients, 77.0 mm Hg in those with decreased CI (<2.5 L/min/m² ) and 57.0 mm Hg in those with preserved CI. Multivariate regression analysis identified mPAP, CI and PaO₂ to be independent predictors of extremely low PvO₂ . Similar results were observed regardless of the severity of PH or the presence of lung disease, PAH or CTEPH. The PaO₂ level needed to avoid tissue hypoxia was higher in patients with mild PH and decreased CI than in those with severe PH and preserved CI (70.2 vs 61.5 mm Hg).

CONCLUSION

These findings indicate that a decreased CI rather than increased mPAP induces tissue hypoxia in PH. Patients with PH and decreased CI may need adjustment of oxygen therapy at higher PaO₂ levels compared with patients with preserved CI.

Pulmonary Hypertension During Pregnancy in New York State, 2003-2014

Objectives This study examined the prevalence and temporal trends in (a) pulmonary hypertension (PH) during pregnancy and (b) mortality and morbidity during pregnancy with and without PH. Methods This was a retrospective observational study of the 2003-2014 New York State Inpatient Database. PH was categorized as primary or secondary and pregnancy as loss or termination of pregnancy, preterm birth, or term birth. The Centers for Disease Control and Prevention definition of maternal morbidity was used, including 17 diagnoses and 5 procedures. Changes were assessed using Cochran-Armitage trend tests. Results Of 2,940,868 pregnancy-related discharges, 746 indicated a diagnosis of PH (25/100,000; 95% CI 24-27). PH was secondary in 677/746 (91%) discharges and 488/746 were term births (65%). Prevalence of secondary PH increased from 17 to 30/100,000 between 2003- 2004 and 2013-2014 (+ 69%; P < 0.001), with an increase in the prevalence of heart valve disease, obesity, and systemic hypertension. Primary PH decreased 81% (P = 0.002). Term-birth PH discharges increased from 13 to 22/100,000 between 2003-2004 and 2013-2014 (+ 66%; P = 0.003), without change in preterm births and loss or termination of pregnancies. No change in morbidity in PH discharges was observed between 2003-2004 and 2013-2014, contrasting with a 64% increase in discharges without PH. Conclusions for Practice Prevalence of secondary PH during pregnancy markedly increased since 2003, underscoring the importance of screening for PH, especially in women with heart valve disease, obesity, or systemic hypertension.

Hypercoagulability in Pulmonary Hypertension

Pulmonary hypertension (PH) is divided into varied pathophysiological and etiologic groupings, as classified by the World Health Organization (WHO). Pulmonary arterial hypertension (PAH), which falls under WHO group 1 PH, is a progressive and potentially fatal disease characterized by a vasoconstrictive, proliferative, and thrombotic phenotype, which leads to increased pulmonary artery pressure, right heart failure, and death. Pathologically, in situ thromboses are found in the small distal pulmonary arteries. Dysregulation of coagulation, platelet function, and endothelial cells may contribute to a prothrombotic state. There is mixed evidence for the use of anticoagulation or antiplatelet therapy in PAH patients.

Relevance of the TAPSE/PASP ratio in pulmonary arterial hypertension

BACKGROUND

The ratio of echocardiography-derived tricuspid annular plane systolic excursion (TAPSE) and pulmonary arterial systolic pressure (PASP) has recently been reported as an independent prognostic parameter in heart failure. The TAPSE/PASP ratio has not been evaluated in detail in patients with pulmonary arterial hypertension (PAH).

METHODS

We analyzed TAPSE/PASP in 290 patients with PAH entered into the Giessen Pulmonary Hypertension Registry between November 2003 and July 2014. The prognostic relevance of TAPSE/PASP was assessed with multivariate Cox regression models, adjusting for clinical covariates, echocardiographic parameters, or hemodynamics, and was confirmed by Kaplan-Meier analyses.

RESULTS

When stratified by tertile of TAPSE/PASP (low: <0.19 mm/mmHg; middle: 0.19-0.32 mm/mmHg; high: >0.32 mm/mmHg), patients in the low tertile showed significantly compromised hemodynamic, functional, and echocardiographic status compared with patients in the middle and high tertiles. In all multivariate models, TAPSE/PASP remained independently associated with overall mortality: the hazard ratio (95% confidence interval) was 1.87 (1.35-2.59) when adjusting for clinical covariates (p < .001), 5.21 (2.17-12.5) when adjusting for echocardiographic parameters (p < .001), 1.92 (1.30-2.83) when adjusting for hemodynamics (p = .001), and 4.13 (2.02-8.48) when adjusting for a selection of previously identified independent echocardiographic and hemodynamic prognostic indicators (p < .001). Kaplan-Meier analyses showed better overall survival in the middle and high tertiles versus the low tertile (log-rank p < .001).

CONCLUSIONS

The TAPSE/PASP ratio is a meaningful prognostic parameter in patients with PAH and is associated with hemodynamics and functional class.