Survival in patients with class III idiopathic pulmonary arterial hypertension treated with first line oral bosentan compared with an historical cohort of patients started on intravenous epoprostenol

Stress hyperglycemia is associated with poor outcome in critically ill patients with pulmonary hypertension

Background and objective

Stress hyperglycemia is common in critically ill patients and is associated with poor prognosis. Whether this association exists in pulmonary hypertension (PH) patients is unknown. The present cohort study investigated the association of stress hyperglycemia with 90-day all-cause mortality in intensive care unit (ICU) patients with PH.

Methods

Data of the study population were extracted from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. A new index, the ratio of admission glucose to HbA1c (GAR), was used to evaluate stress hyperglycemia. The study population was divided into groups according to GAR quartiles (Q1-Q4). The outcome of interest was all-cause mortality within 90 days, which was considered a short-term prognosis.

Result

A total of 53,569 patients were screened. Ultimately, 414 PH patients were enrolled; 44.2% were male, and 23.2% were admitted to the cardiac ICU. As the GAR increased from Q2 to Q4, the groups had lower creatinine levels, longer ICU stays, and a higher proportion of renal disease. After adjusting for confounding factors such as demographics, vital signs, and comorbidities, an elevated GAR was associated with an increased risk of 90-day mortality.

Conclusion

Stress hyperglycemia assessed by the GAR was associated with increased 90-day mortality in ICU patients with PH.

Right Ventricular Energy Failure Predicts Mortality in Patients With Pulmonary Hypertension

Right ventricular (RV) failure has a significant adverse impact on pulmonary hypertension (PH) prognosis. None of the currently used parameters directly assess whether RV fails to provide enough energy output to propel the blood through diseased pulmonary vascular system. Furthermore, most of the current parameters are affected by the volume status of the patient. We aimed to explore whether RV energy failure has a predictive power for mortality on top of the established prognostic risk parameters in patients with PH. We screened 723 cases from our database. A total of 3 sets of binary regression analyses were executed to determine the hazard ratios (HRs) of RV energy failure for 5-year mortality in clinical, echocardiographic, and hemodynamic context, using adjustment variables chosen according to previous studies. The final study population encompassed 549 cases. A total of 77 patients died during the 5-year follow-up (14%). RV energy failure was observed in 146 of 549 patients (26.6%). In the univariate model, RV energy failure strongly associated with increased long-term mortality (HR 4.25, 95% confidence interval [CI] 2.58 to 7.00, p <0.001). It also emerged as a significant predictor of long-term mortality in clinical and hemodynamic multivariate models (HR 2.59, 95% CI 1.43 to 4.67, p = 0.002 and HR 2.05, 95% CI 1.15 to 3.63, p = 0.015, respectively). In conclusion, our study indicates that the presence of RV energy failure independently predicts long-term mortality in PH.

Strategies for optimizing intravenous prostacyclin-analog therapy in patients with pulmonary arterial hypertension

INTRODUCTION

Intravenous prostacyclin-analogs (PCA, e.g. epoprostenol, treprostinil, iloprost) have become an essential part in the therapy of patients with pulmonary hypertension (PH), mainly pulmonary arterial hypertension (PAH). They show considerable differences in pharmacology. A combination therapy including intravenous drugs is regarded as the 'gold standard' in most of PAH patients.

AREAS COVERED

This review discusses and summarizes the studies and concepts on which this therapy is based. To date, intravenous prostacyclin-analogs are mainly administered when standard therapy fails to improve patients to low-risk status. However, preliminary data from uncontrolled studies suggest that an 'upfront triple' therapy including intravenous or subcutaneous prostacyclin-analogs could be preferable in selected patients.

EXPERT OPINION

Various IV PCA have been evaluated in the treatment of patients with PAH. Today, combination therapy is the 'gold standard' for the majority of patients. Intravenous PCA is recommended from functional class III onwards. Timing of its initiation is still a point of discussion. An escalation of therapy to IV or SC PCA is always necessary if a low-risk status cannot be achieved with other targeted therapies. Preliminary data suggest that selected patients could benefit from an 'upfront triple' therapy. Controlled studies on which such recommendation could be based are lacking.

Prediction Models and Scores in Pulmonary Hypertension: A Review

BACKGROUND

Pulmonary arterial hypertension (PAH) is a serious disease with increased morbidity and mortality. The need for an individualized patient treatment approach necessitates the use of risk assessment in PAH patients. That may include a range of hemodynamic, clinical, imaging and biochemical parameters derived from clinical studies and registry data.

OBJECTIVE

In the current systematic review, we summarize the available data on risk prognostic models and scores in PAH and we explore the possible concordance amongst different risk stratification tools in PAH.

METHODS

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines aided the performance of this systematic review. Eligible studies were identified through a literature search in the electronic databases PubMed, Science Direct, Google Scholar and Cochrane with the use of various combinations of MeSH and non-MeSH terms, with a focus on PAH.

RESULTS

Overall, 25 studies were included in the systematic review; out of them, 9 were studies deriving prognostic equations and risk scores and 16 were validating studies of an existing score. The majority of risk stratification scores use hemodynamic data for the assessment of prognosis, while others also include clinical and demographic variables in their equations. The risk discrimination in the overall PAH population was adequate, especially in differentiating the low versus high-risk patients, but their discrimination ability in the intermediate groups remained lower. Current ESC/ERS proposed risk stratification score utilizes a limited number of parameters with prognostic significance, whose prognostic ability has been validated in European patient populations.

CONCLUSION

Despite improvement in risk estimation of prognostic tools of the disease, PAH morbidity and mortality remain high, necessitating the need for the risk scores to undergo periodic re-evaluation and refinements to incorporate new data into predictors of disease progression and mortality and, thereby, maintain their clinical utility.

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.

Intravenous prostacyclin-analogue therapy in pulmonary arterial hypertension - A review of the past, present and future

Therapy with intravenous prostacyclin analogues in patients with pulmonary arterial hypertension (PAH) has been established for decades and is an integral component of the current guidelines for the treatment of pulmonary hypertension. Initially, these drugs were infused by external pump systems via tunnelled right atrial catheters with the need for cooling and frequent exchange of drug reservoirs. Associated complications included, among others, catheter-related infections. More recently, fully implantable pump systems have been developed with drug reservoirs that are filled transcutaneously, allowing intervals between refills of several weeks. This technique results in a low rate of infections. Epoprostenol, iloprost and treprostinil have all been used intravenously in PAH, but titration, dosing and dose escalation in long-term therapy are not standardized. Intravenous prostacyclin analogues are still under-used, despite available data suggesting that early and broad application of these therapies as part of risk-oriented, guideline-directed combination therapy for patients with PAH may lead to a survival benefit. This review provides a detailed overview of the drugs, infusion systems and dosing strategies used for intravenous therapy in patients with PAH.

Acute vasoreactivity testing predicts outcome of idiopathic pulmonary arterial hypertension patients with a negative acute response

BACKGROUND

Acute vasoreactivity testing (AVT) during right heart catheterization (RHC) is performed in certain subsets of patients with pulmonary arterial hypertension (PAH) in order to identify those who benefit from calcium channel blockers. The present study aimed to investigate the prognostic value of pre-AVT, post-AVT, and changes in AVT (ΔAVT) parameters for idiopathic PAH (IPAH) patients with a negative acute response, and to identify sex differences that could be of prognostic value.

METHODS

A total of 487 incident IPAH patients (171 males and 316 females) with a negative acute response to AVT were recruited from Shanghai Pulmonary Hospital between 2009 and 2018. Outcomes were predicted using the Kaplan-Meier curve and univariate/multivariate Cox regression analyses. All patients were followed up till January 2020, with outcome specified as all-cause mortality.

RESULTS

Inhalation of iloprost aerosol improved the hemodynamic parameters for all patients. Post-PVR was decreased, and post-cardiac output (post-CO) and post-cardiac index (post-CI) were increased compared with pre-AVT parameters among males. Increased post- artery oxygen saturation (post-SaO2) and decreased post-mean right atrium pressure (post-mRAP) were also observed in females. For all patients, pre-CO ≥3.25 L/min, post-mPAP <53 mmHg, and post-mixed venous oxygen saturation (post-SvO2) ≤63% were parameters suggesting better prognosis. For males, patients with pre-PVR <12.47 Wood units, pre-SvO2 ≥64%, and post-mean pulmonary artery pressure (post-mPAP) <51 mmHg had a better prognosis. For females, patients with ΔmPAP ≥-4 mmHg and ΔPVR ≥-0.25 Wood units had better outcomes.

CONCLUSIONS

AVT parameters, including pre-AVT, post-AVT and ΔAVT, have a more important prognostic value than currently used for identify a small subgroup of patients with PAH who are suitable for high-dose calcium channel blockers. Sex differences in AVT parameters suggest that sex should be taken into account in estimating prognosis.

Identification of Potential Biomarkers for Anti-PD-1 Therapy in Melanoma by Weighted Correlation Network Analysis

Melanoma is the most malignant form of skin cancer, which seriously threatens human life and health. Anti-PD-1 immunotherapy has shown clinical benefits in improving patients' overall survival, but some melanoma patients failed to respond. Effective therapeutic biomarkers are vital to evaluate and optimize benefits from anti-PD-1 treatment. Although the establishment of immunotherapy biomarkers is well underway, studies that identify predictors by gene network-based approaches are lacking. Here, we retrieved the existing datasets (GSE91061, GSE78220 and GSE93157, 79 samples in total) on anti-PD-1 therapy to explore potential therapeutic biomarkers in melanoma using weighted correlation network analysis (WGCNA), function validation and clinical corroboration. As a result, 13 hub genes as critical nodes were traced from the key module associated with clinical features. After receiver operating characteristic (ROC) curve validation by an independent dataset (GSE78220), six hub genes with diagnostic significance were further recovered. Moreover, these six genes were revealed to be closely associated not only with the immune system regulation, immune infiltration, and validated immunotherapy biomarkers, but also with excellent prognostic value and significant expression level in melanoma. The random forest prediction model constructed using these six genes presented a great diagnostic ability for anti-PD-1 immunotherapy response. Taken together, IRF1, JAK2, CD8A, IRF8, STAT5B, and SELL may serve as predictive therapeutic biomarkers for melanoma and could facilitate future anti-PD-1 therapy.

Combined Methods (Formal Adjusted Indirect Comparison, Meta-Analysis and Principal Component Analysis) Comparisons of the Safety and Efficacy of Ambrisentan, Bosentan, and Sildenafil in the Patients With Pulmonary Arterial Hypertension

BACKGROUND

Three oral drugs (ambrisentan, bosentan, and sildenafil) have been widely used to treat patients with pulmonary arterial hypertension (PAH). 1) There are no studies that directly compare the safety and efficacy of these three drugs. Existing studies could not meet the physician's need to select the most beneficial drugs for patients. 2) Principal component analysis is mainly used for scale analysis and has not been reported in clinical field. 3) When the results of the indirect meta-analysis were not satisfactory, no new solutions have been proposed in existing meta-analysis studies.

METHODS

The overall process of this study is divided into 4 steps 1) literature search and data extraction; 2) principal component analysis; 3) common reference-based indirect comparison meta-analysis; 4) formal adjusted indirect comparison.

RESULTS

Nine randomized controlled trials (RCTs) experiments and eight long-term experiments were selected. The main influencing factors are mortality, 6-min walk distance (6MW), mean pulmonary arterial pressure (PAP), cardiac index (CI) by principal component analysis. There was no significant heterogeneity among the indirect meta-analysis of three drugs. But in the formal adjusted indirect comparison 1) the level of PAP of sildenafil group (60.5 ± 22.35, 220) was higher than that of the other three groups, placebo (53.5 ± 17.63, 507) (p < 0.001), ambrisentan (49.5 ± 15.08, 130) (p < 0.001), and bosentan (54.6 ± 118.41, 311) (p < 0.001); 2) the level of CI of sildenafil group (54 ± 18, 311) was higher than that of the other three groups, placebo (2.7 ± 1.09, 518) (p < 0.001), ambrisentan (2.5 ± 0.75, 130) (p < 0.001), and bosentan (2.5 ± 1.06, 333) (p < 0.001). In addition, sildenafil significantly improved the survival rate comparing with ambrisentan and bosentan.

CONCLUSIONS

The results of this study suggest that sildenafil might be more suitable for long-term treatment of PAH patients than ambrisentan and bosentan. In order to enable clinicians to draw conclusions more quickly and directly in the data-rich literature, we suggest the use of principal component analysis combined with formal adjusted indirect comparison to compare the efficacy and safety of drugs.

Changed hemodynamics in acute vasoreactivity testing: prognostic predictors in chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is similar to pulmonary arterial hypertension (PAH) in its pathogenesis. Changed hemodynamic parameters in acute vasoreactivity testing (AVT) have proved to be prognostic predictors of PAH. We wanted to determine whether these changed indices also impacted the prognosis of CTEPH. Data was retrieved for 86 CTEPH patients who underwent right heart catheterization (RHC) with AVT at Shanghai Pulmonary Hospital from 2009 to 2018 and following up for 20 ± 15 months for event. Cox proportional hazards models were performed to determine the predictors of independent event-free survival. Receiver operating characteristic curve was plotted to determine the cut-off value of independent parameters in CTEPH. Kaplan-Meier method and log-rank test were used to perform the Survival analyses. Forty seven patients had an event. Many hemodynamic indices improved after AVT. The event-free group had better mean right atrial pressure, mean pulmonary arterial pressure, pulmonary vascular resistance (PVR) and oxygen saturation of mixed venous blood (SvO2) both at baseline and after AVT. The event-free group also showed higher cardiac output (CO) and cardiac index (CI) after AVT. Among the changed hemodynamic parameters during the AVT, ΔCO, ΔCO/baseline CO, ΔCI, ΔCI/baseline CI and ΔPVR/baseline PVR were significantly higher in the event-free group. Foremost, ΔPVR/baseline PVR, PVR after AVT and baseline SvO2 were independent predictors for event-free survival. Patients with SvO2 ≥ 61.65% at baseline or PVR < 8.09 WU after AVT or ΔPVR/baseline PVR ≥ 0.054 had significantly better survival. Hemodynamic indices both at baseline and after AVT as well as the changes in these indices reflected the severity of CTEPH. Baseline SvO2, PVR after AVT, and ΔPVR/baseline PVR could be used as independent predictors to estimate the outcomes of CTEPH patients.

Bosentan for Treatment of Pediatric Idiopathic Pulmonary Arterial Hypertension: State-of-the-Art

Idiopathic pulmonary arterial hypertension (IPAH) is a complex disease associated with progressive deterioration. Targeted therapy for IPAH has improved in the last several decades. However, there remain many challenges to current treatment of children with IPAH, including poor prognosis and a median survival of 0.8 years. Endothelin-1 (ET-1) appears to be a key mediator in the pathogenesis of IPAH, with elevated concentrations in the plasma. Bosentan, an endothelin receptor antagonist, has been confirmed in Food and Drug Administration (FDA) to effectively treat IPAH when administered in recent studies. This review focuses on related studies and advance of bosentan in the treatment of IPAH in children.

Anxiety and depression in patients with pulmonary hypertension: impact and management challenges

Background

Anxiety and depression are frequent disorders in patients with pulmonary arterial hypertension (PAH), but despite this only less than one-fourth of them is treated. Our aim was to review the studies regarding the prevalence and the impact of anxiety and depression and to propose management challenges.

Methods

A literature review regarding 1) anxiety and depression studies in PAH patients and caregivers, 2) psychological interventions, 3) slow breathing approach, and 4) pharmacological approach was performed, based on evidence of effectiveness through a search of the most well-known databases (Cochrane Library, Medline, PsychINFO [2004–2018]).

Results

The prevalence of mental disorders in PAH patients lies between 7.5% and 53% for depression and 19% and 51% for anxiety and panic disorders. The latest guidelines of the European Society of Cardiology recommend a psychological support with a class of recommendation I and a level of evidence c. The analysis of psychological intervention shows that at present there is no evidence of specific psychological interventions in these patients. However, treatment approaches based on other chronic illnesses are suggested, especially based on relaxation training, slow breathing, and cognitive behavioral therapy. Finally, data concerning the use of antidepressant drugs are conflicting.

Conclusion

Firstly, our data demonstrate a common underestimation of mental disorders by health professionals and secondly, the need of implementing appropriate methods of screening for mental disorders in PAH patients. However, the paucity of large observational studies in this area requires the attention of researchers. The evidence about optimal approaches for managing anxiety and depression in PAH also remains unclear and largely speculative. The challenge is the introduction of routine psychological intervention, as suggested by the European Society of Cardiology and already applied in other chronic disease.

A modified risk score in one-year survival rate assessment of group 1 pulmonary arterial hypertension

BACKGROUND

Risk assessment of pulmonary arterial hypertension (PAH) contributes to its management. Unfortunately, the existing risk assessment approaches are defective for clinicians to practice in daily clinical settings to some extent.

METHODS

We designed a modified Risk Assessment Score of PAH (mRASP) comprising four non-invasive variables which were World Health Organization functional class(WHO FC), 6-min walk distance (6MWD), N-terminal of the pro-hormone brain natriuretic peptide(NT-pro BNP), and right atrial area(RAA), then validated it in the prediction of one-year survival rate for patients with PAH by contrast with the REVEAL risk score.

RESULTS

For the validation cohort(n = 216), the predicted one-year survival rate were 95-100%, 90-95%, and < 90% in the mRASP risk score strata of 0-2, 3-5, and 6-8, respectively; meanwhile, the observed one-year survival rates were 97.1, 92.6, and 52.2%, in each corresponding stratum, respectively. The mRASP (c-index = 0.727) demonstrated similar predictive power in contrast with the REVEAL risk assessment score (c-index = 0.715) in the prediction of one-year survival rate.

CONCLUSION

The mRASP is an eligible risk assessment tool for the prognostic assessment of PAH. In contrast with the REVEAL score, it demonstrated similar predictive power and accuracy, with extra simplicity and convenience.

Risk stratification strategy and assessment of disease progression in patients with pulmonary arterial hypertension: Updated Recommendations from the Cologne Consensus Conference 2018

In the summer of 2016, delegates from the German Respiratory Society, the German Society of Cardiology and the German Society of Pediatric Cardiology met in Cologne, Germany, to define consensus-based practice recommendations for the management of patients with pulmonary arterial hypertension (PAH). These recommendations were built on the 2015 European Pulmonary Hypertension guidelines and included new evidence, where available, and were last updated in the spring of 2018. This article focusses on the proposed risk stratification and assessment of disease progression in patients with pulmonary arterial hypertension (PAH), covering 3 parts: In part 1, methods and markers that are recommended to assess severity and progression of PAH are discussed and commented. These updated comments incorporate most recent data as well as challenges arising from the variability of phenotypes of PAH patients with increasing cardiopulmonary comorbidities. In part 2, the proposed ESC/ERS risk stratification strategy is discussed, together with a review of the recent validation studies from different European registries. Finally, in part 3, the working group of the Cologne Consensus Conference provides recommendations on how risk assessment may be implemented in routine clinical practice and may serve clinical decision making.

The Regulation of Pulmonary Vascular Tone by Neuropeptides and the Implications for Pulmonary Hypertension

Pulmonary hypertension (PH) is an incurable, chronic disease of small pulmonary vessels. Progressive remodeling of the pulmonary vasculature results in increased pulmonary vascular resistance (PVR). This causes secondary right heart failure. PVR is tightly regulated by a range of pulmonary vasodilators and constrictors. Endothelium-derived substances form the basis of most current PH treatments. This is particularly the case for pulmonary arterial hypertension. The major limitation of current treatments is their inability to reverse morphological changes. Thus, there is an unmet need for novel therapies to reduce the morbidity and mortality in PH. Microvessels in the lungs are highly innervated by sensory C fibers. Substance P and calcitonin gene-related peptide (CGRP) are released from C-fiber nerve endings. These neuropeptides can directly regulate vascular tone. Substance P tends to act as a vasoconstrictor in the pulmonary circulation and it increases in the lungs during experimental PH. The receptor for substance P, neurokinin 1 (NK1R), mediates increased pulmonary pressure. Deactivation of NK1R with antagonists, or depletion of substance P prevents PH development. CGRP is a potent pulmonary vasodilator. CGRP receptor antagonists cause elevated pulmonary pressure. Thus, the balance of these peptides is crucial within the pulmonary circulation (Graphical Abstract). Limited progress has been made in understanding their impact on pulmonary pathophysiology. This is an intriguing area of investigation to pursue. It may lead to promising new candidate therapies to combat this fatal disease. This review provides a summary of the current knowledge in this area. It also explores possible future directions for neuropeptides in PH.

Exercise training in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is characterized by a continuous increase in pre-capillary pulmonary vascular resistance (PVR) with a progressive reduction of cardiac output (CO). Similar to what occurs in left heart failure (HF), this represents the initial phase of a syndrome characterized by the progressive development of dyspnea and fatigue with increasing deterioration of exercise tolerance. Although the therapies introduced in the last two decades have determined a significant improvement of the clinical conditions of PAH patients, they have a little impact on exercise capacity and prognosis. However, as previously demonstrated for HF, recent pilot studies have reported that physical and respiratory rehabilitation may have a specific role in the management of PAH. Despite potential risks, so far all studies agree that exercise training (ET) improves exercise capacity, quality of life (QoL), muscle function and pulmonary circulation. We will review the pathophysiological mechanisms underlying the functional incompetence of PAH patients, the effects of ET on clinical and functional parameters, the selection criteria for inclusion of patients in a training program, the suggested monitoring of beneficial effects or possible side effects induced by ET. Finally, we discuss of the possible exercise induced amelioration of prognosis in PAH.

Oral pulmonary vasoactive drugs achieve hemodynamic eligibility for liver transplantation in portopulmonary hypertension

BACKGROUND AND AIMS

Portopulmonary hypertension (POPH) hampers survival of patients with cirrhosis and portal hypertension and may preclude liver transplantation (LT). Management of such patients with oral pulmonary vasoactive drugs (PVD) has not been standardized. Our aim was to assess the efficacy and safety of oral PVD for management of POPH.

METHODS

All patients treated by oral PVD (bosentan, ambrisentan, sildenafil, tadalafil) for POPH were retrospectively studied. Significant response was defined for the patients who reached the following LT eligibility criteria: mean pulmonary artery pressure (MPAP) <35mmHg or MPAP between 35 and 50mmHg with pulmonary vascular resistance (PVR) <250dynscm^-5.

RESULTS

20 patients were followed for 38 (19-57) months. Oral PVD improved MPAP (-8 [-19, +2]mmHg), PVR (-201 [-344, -68]dynscm^-5) and 6-min walk distance (+52 [-51, +112] m). Fifty-three percent of evaluable patients reached eligibility to LT criteria, of whom 5 were transplanted. Baseline MPAP>51mmHg and/or PVR>536dynscm^-5 predicted non response to treatment. Five-years survival was 53%. No worsening of cirrhosis or serious adverse effect was recorded.

CONCLUSION

Oral pulmonary vasoactive drugs are safe in cirrhotic patients with POPH. These treatments improved hemodynamic conditions allowing patients access to liver transplantation eligibility.

Epoprostenol and pulmonary arterial hypertension: 20 years of clinical experience

Epoprostenol was the first therapy to be approved for the treatment of pulmonary arterial hypertension (PAH). In the 20 years since the introduction of this prostacyclin analogue, the outlook for patients with PAH has improved, with survival rates now double those from the era before the development of disease-specific treatments. Today, there are a large amount of data on the clinical role of prostacyclin treatments and a body of evidence attesting the efficacy of epoprostenol in improving exercise capacity, key haemodynamic parameters and PAH symptoms, as well as in reducing mortality. The place of epoprostenol in the therapeutic management of PAH continues to evolve, with the development of new formulations and use in combination with other drug classes. In this review, we provide a historical perspective on the first 20 years of epoprostenol, a therapy that led to evidence-based study of PAH-specific treatments and the subsequent expansion of treatment options for PAH.

The evolution of the place of epoprostenol in the management of pulmonary arterial hypertensionhttp://ow.ly/OkY3303N2CX

Cost Effectiveness of First-Line Oral Therapies for Pulmonary Arterial Hypertension: A Modelling Study

BACKGROUND

In recent years, a significant number of costly oral therapies have become available for the treatment of pulmonary arterial hypertension (PAH). Funding decisions for these therapies requires weighing up their effectiveness and costs.

OBJECTIVE

The aim of this study was to assess the cost effectiveness of monotherapy with oral PAH-specific therapies versus supportive care as initial therapy for patients with functional class (FC) II and III PAH in Canada.

METHODS

A cost-utility analysis, from the perspective of a healthcare system and based on a Markov model, was designed to estimate the costs and quality-adjusted life-years (QALYs) associated with bosentan, ambrisentan, riociguat, tadalafil, sildenafil and supportive care for PAH in treatment-naïve patients. Separate analyses were conducted for cohorts of patients commencing therapy at FC II and III PAH. Transition probabilities, based on the relative risk of improving and worsening in FC with treatment versus placebo, were derived from a recent network meta-analysis. Utility values and costs were obtained from published data and clinical expert opinion. Extensive sensitivity analyses were conducted.

RESULTS

Analysis suggests that sildenafil is the most cost-effective therapy for PAH in patients with FC II or III. Sildenafil was both the least costly and most effective therapy, thereby dominating all other treatments. Tadalafil was also less costly and more effective than supportive care in FC II and III; however, sildenafil was dominant over tadalafil. Even given the uncertainty within the clinical inputs, the probabilistic sensitivity analysis showed that apart from sildenafil and tadalafil, the other PAH therapies had negligible probability of being the most cost effective.

CONCLUSION

The results show that initiation of therapy with sildenafil is likely the most cost-effective strategy in PAH patients with either FC II or III disease.

Present and future treatment strategies for pulmonary arterial hypertension : focus on phosphodiesterase-5 inhibitors

Idiopathic pulmonary arterial hypertension (IPAH) is a rare progressive disorder historically associated with mortality in <3 years post-diagnosis. The etiology of PAH is complex, multifactorial, and likely involves the interplay between genetic and environmental factors. These are reviewed with emphasis on the nitric oxide pathway. Use of treatment modalities including vasodilator therapy have resulted in improved symptoms, hemodynamics, and survival in these patients. Vasodilators, including the calcium channel antagonists, prostanoids, and endothelin receptor antagonists, have been used to counteract potential imbalances in vasoactive mediators in PAH patients; all have produced improved long-term symptomatology and hemodynamics. Only the prostanoid epoprostenol has improved survival in IPAH patients. Although these medications have worked well in many patients with PAH, each of them has limitations. The phosphodiesterase-5 (PDE-5) inhibitors are a relatively new form of treatment for PAH. They are designed to potentiate the effects of cyclic guanosine monophosphate, thereby mimicking endogenous nitric oxide within the vasculature. PDE-5 inhibitors are selective pulmonary vasodilators effective in animal models of pulmonary hypertension. The published clinical studies evaluating their use have been small in size to date but appear to demonstrate benefit. The recently completed 12-week randomized placebo-controlled Sildenafil Use in Pulmonary Hypertension (SUPER-1) trial demonstrated improvement in 6-minute walk distance and hemodynamics in patients receiving sildenafil. These data suggest that the PDE-5 inhibitors are effective in treating PAH and that it is likely that their usage will increase over time. The purpose of this review is to present a current view of the pathogenesis and treatment of PAH, with an emphasis on the use of PDE-5 inhibitors in these patients.

2015 ESC/ERS Guidelines for the diagnosis and treatment of pulmonary hypertension

Guidelines summarize and evaluate all available evidence on a particular issue at the time of the writing process, with the aim of assisting health professionals in selecting the best management strategies for an individual patient with a given condition, taking into account the impact on outcome, as well as the risk–benefit ratio of particular diagnostic or therapeutic means. Guidelines and recommendations should help health professionals to make decisions in their daily practice. However, the final decisions concerning an individual patient must be made by the responsible health professional(s) in consultation with the patient and caregiver as appropriate.

Endothelial NO-Synthase Gene-Enhanced Progenitor Cell Therapy for Pulmonary Arterial Hypertension: The PHACeT Trial

RATIONALE

Pulmonary arterial hypertension (PAH) remains a progressive and eventually lethal disease characterized by increased pulmonary vascular resistance because of loss of functional lung microvasculature, primarily at the distal (intracinar) arteriolar level. Cell-based therapies offer the potential to repair and regenerate the lung microcirculation and have shown promise in preclinical evaluation in experimental models of PAH.

OBJECTIVE

The Pulmonary Hypertension and Angiogenic Cell Therapy (PHACeT) trial was a phase 1, dose-escalating clinical study of the tolerability of culture-derived endothelial progenitor cells, transiently transfected with endothelial nitric oxide synthase, in patients with PAH refractory to PAH-specific therapies.

METHODS AND RESULTS

Seven to 50 million endothelial nitric oxide synthase-transfected endothelial progenitor cells, divided into 3 doses on consecutive days, were delivered into the right atrium via a multiport pulmonary artery catheter during continuous hemodynamic monitoring in an intensive care unit setting. Seven patients (5 women) received treatment from December 2006 to March 2010. Cell infusion was well tolerated, with no evidence of short-term hemodynamic deterioration; rather, there was a trend toward improvement in total pulmonary resistance during the 3-day delivery period. However, there was 1 serious adverse event (death) which occurred immediately after discharge in a patient with severe, end stage disease. Although there were no sustained hemodynamic improvements at 3 months, 6-minute walk distance was significantly increased at 1, 3, and 6 months.

CONCLUSION

Delivery of endothelial progenitor cells overexpressing endothelial nitric oxide synthase was tolerated hemodynamically in patients with PAH. Furthermore, there was evidence of short-term hemodynamic improvement, associated with long-term benefits in functional and quality of life assessments. However, future studies are needed to further establish the efficacy of this therapy.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00469027.

Recent strategies in treatment of pulmonary arterial hypertension, a review

Pulmonary arterial hypertension (PAH) is a disease characterized by an elevation in pulmonary artery pressure that can lead to right ventricular failure and death. The pulmonary circulation has to accommodate the entire cardiac output in each cardiac cycle and evolution has adapted to this by making it a low-pressure high-flow system. However, pathology can affect both the arterial and venous components of this system. Pulmonary venous hypertension mainly refers to diseases that result in elevated venous pressure and occurs mainly from mitral valve and left-sided heart disease. Standard treatment options include oral anticoagulation, diuretics, oxygen supplementation, and for a small percentage of patients, calcium channel blockers. Newer treatments include prostacyclin analogues, endothelin receptor antagonists, and phosphodiesterase type 5 inhibitors. This article reviews the current treatments strategies for PAH and provides guidelines for its management.

Optimal management of pulmonary arterial hypertension: prognostic indicators to determine treatment course

Pulmonary arterial hypertension (PAH) is a rapidly progressive pulmonary vascular disease with a multifactorial etiopathogenesis that can result in right-sided heart failure and death. A number of studies indicate that an early therapeutic intervention yields better results on disease progression as compared to delayed treatment. In this review, we will analyze treatment strategies that may be used for monitoring disease progression and for guiding treatment decisions. Several factors (ie, symptoms, functional class, exercise capacity as assessed by a walking test and cardiopulmonary stress testing, hemodynamic parameters, cardiac magnetic resonance imaging, and plasma levels of biochemical markers) have been prognostic of survival. These indicators may be used both at the time of diagnosis and during treatment follow-up. No resolutive therapy is currently available for PAH; however, in the last decade, the advent of specific pharmacological treatments has given new hope to patients suffering from this debilitating disease with a poor prognosis. Combination drug therapies offer increased benefits over monotherapy, and current guidelines recommend a sequential “add on” design approach for patients in functional class II–IV. The goal-oriented “treat to target” therapy sets the timing for treatment escalation in case of inadequate response to currently known prognostic indicators. To date, further longitudinal studies should be urgently conducted to identify new goals that may improve therapeutic strategies in order to optimize personalized treatment in PAH patients.

Saudi guidelines on the diagnosis and treatment of pulmonary hypertension: 2014 updates

The Saudi Association for Pulmonary Hypertension (previously called Saudi Advisory Group for Pulmonary Hypertension) has published the first Saudi Guidelines on Diagnosis and Treatment of Pulmonary Arterial Hypertension back in 2008.[1] That guideline was very detailed and extensive and reviewed most aspects of pulmonary hypertension (PH). One of the disadvantages of such detailed guidelines is the difficulty that some of the readers who just want to get a quick guidance or looking for a specific piece of information might face.

All efforts were made to develop this guideline in an easy-to-read form, making it very handy and helpful to clinicians dealing with PH patients to select the best management strategies for the typical patient suffering from a specific condition. This Guideline was designed to provide recommendations for problems frequently encountered by practicing clinicians involved in management of PH. This publication targets mainly adult and pediatric PH-treating physicians, but can also be used by other physicians interested in PH.

Myocardial and anti-inflammatory effects of chronic bosentan therapy in monocrotaline-induced pulmonary hypertension

INTRODUCTION AND OBJECTIVES

Endothelin-1 antagonists are increasingly used in the treatment of pulmonary hypertension despite the lack of knowledge of their myocardial and systemic effects. We assessed the right ventricular myocardial and systemic effects of endothelin-1 antagonists in monocrotaline-induced pulmonary hypertension.

METHODS

Male Wistar rats (180-200 g, n=57) randomly received 60 mg/kg monocrotaline or vehicle subcutaneously. Two days later, bosentan was randomly started (300 mg/kg/day) by oral route in a subgroup of monocrotaline-injected rats, while the other monocrotaline-injected and control rats received vehicle. At 25-30 days, invasive hemodynamic assessment was performed under anesthesia, arterial blood samples were collected for gas analysis and plasma was extracted for quantification of endothelin-1, cytokines, nitrates and 6-keto-prostaglandin F1α. Right ventricular myocardium was collected for assessment of cyclooxygenase and nitric oxide synthase activity and gene expression.

RESULTS

The monocrotaline group developed pulmonary hypertension, low cardiac output, right ventricular hypertrophy and dilation, changes in gene expression and inflammatory activation that were attenuated in the group treated with bosentan. From a functional point of view, this group had improved right ventricular function and preserved ventriculo-vascular coupling, without deterioration in arterial gas parameters or systemic hypotension. In molecular terms, they showed reduced endothelin-1 and cytokine levels, decreased right ventricular inducible nitric oxide synthase and cyclooxygenase-2 activity and increased nitrate plasma levels compared with the non-treated group.

CONCLUSIONS

In this study we demonstrate that besides attenuating pulmonary hypertension, bosentan has beneficial hemodynamic, myocardial and anti-inflammatory effects.

Attenuation of monocrotaline-induced pulmonary hypertension by luminal adeno-associated virus serotype 9 gene transfer of prostacyclin synthase

Idiopathic pulmonary arterial hypertension (iPAH) is associated with high morbidity and mortality. We evaluated whether luminal delivery of the human prostacyclin synthase (hPGIS) cDNA with adeno-associated virus (AAV) vectors could attenuate PAH. AAV serotype 5 (AAV5) and AAV9 vectors containing the hPGIS cDNA under the control of a cytomegalovirus-enhanced chicken β-actin (CB) promoter or vehicle (saline) were instilled into lungs of rats. Two days later, rats were injected with monocrotaline (MCT, 60 mg/kg) or saline. Biochemical, hemodynamic, and morphologic assessments were performed when the rats developed symptoms (3-4 weeks) or at 6 weeks. Luminal (airway) administration of AAV5 and AAV9CBhPGIS vectors (MCT-AAV5 and MCT-AAV9 rats) significantly increased plasma levels of 6-keto-PGF1(α) as compared with MCT-controls, and closely resembled levels measured in rats not treated with MCT (saline-saline). Right ventricular (RV)/left ventricular (LV)+septum (S) ratios and RV systolic pressure (RVSP) were greater in MCT-control rats than in saline-saline rats, whereas the ratios and RVSP in MCT-AAV5CBhPGIS and MCT-AAV9CBhPGIS rats were similar to saline-saline rats. Thickening of the muscular media of small pulmonary arteries of MCT-control rats was detected in histological sections, whereas the thickness of the muscular media in MCT-AAV5CBhPGIS and MCT-AAV9CBhPGIS rats was similar to saline-saline controls. In experiments with different promoters, a trend toward increased levels of PGF1(α) expression was detected in lung homogenates, but not plasma, of MCT-treated rats transduced with an AAV9-hPGIS vector containing a CB promoter. This correlated with significant reductions in the RV/LV+S ratio and RVSP in MCT-AAV9CBhPGIS rats that resembled levels in saline-saline rats. No changes in levels of PGF1(α), RV/LV+S, or RVSP were detected in rats transduced with AAV9-hPGIS vectors containing a modified CB promoter (CB7) or a distal epithelial cell-specific promoter (CC10). Thus, AAV9CBhPGIS vectors prevented development of MCT-induced PAH and associated pulmonary vascular remodeling.

Prognostic Value of Cardiovascular Magnetic Resonance Imaging Measurements Corrected for Age and Sex in Idiopathic Pulmonary Arterial Hypertension

Background—

There are limited data on the prognostic value of cardiovascular magnetic resonance measurements in idiopathic pulmonary arterial hypertension, with no studies investigating the impact of correction of cardiovascular magnetic resonance indices for age and sex on prognostic value.

Methods and Results—

Consecutive patients with idiopathic pulmonary arterial hypertension underwent cardiovascular magnetic resonance imaging at 1.5T. Steady-state free precession cardiac volumes and mass measurements were corrected for age, sex, and body surface area according to reference data and prognostic significance assessed. A total of 80 patients with idiopathic pulmonary arterial hypertension were identified, and 23 patients died during the mean follow-up of 32±14 months. Corrected for age, sex, and body surface area, right ventricular end-systolic volume ( P =0.004) strongly predicted mortality, independent of World Health Organization functional class, mean right atrial pressure, cardiac index, and mixed venous oxygen saturations.

Conclusions—

Consideration should be given to correcting cardiovascular magnetic resonance measures for age, sex, and body surface area, particularly given the changing demographics of patients with idiopathic pulmonary arterial hypertension. Corrected right ventricular end-systolic volume is a strong prognostic marker in idiopathic pulmonary arterial hypertension, independent of invasively derived measurements, mean right atrial pressure cardiac index, and mixed venous oxygen saturations.

A multicenter, retrospective study of patients with pulmonary arterial hypertension transitioned from parenteral prostacyclin therapy to inhaled iloprost

Pulmonary arterial hypertension (PAH) is characterized by progressive increases in pulmonary vascular resistance, leading to right heart failure and death. Guidelines recommend customization of treatment, necessitating the development of effective strategies for transitioning patients among treatments. In this study, we characterized our experience with patient transitions from parenteral prostacyclin to inhaled iloprost. We retrospectively assessed records from 11 centers of 37 consecutive patients with PAH aged ≥ 18 years who were treated with intravenous (IV) or subcutaneous (SC) prostacyclin analogues and transitioned to inhaled iloprost. The transition period began on the first day of inhaled iloprost with the intent of discontinuing parenteral prostacyclin and ended on the first day on inhaled iloprost free of parenteral prostacyclin. Persistence was defined as the absence of (1) parenteral prostacyclin while remaining on inhaled iloprost during post-transition Days 1-90 and (2) no reinitiation of parenteral prostacyclin during post-transition Days 90-365. All patients were clinically stable before transitioning to inhaled iloprost. The mean age was 46.5 years, 70.3% were female, 51.4% had idiopathic PAH, and 43.0% were in New York Heart Association Functional Class III. Among patients with an overlapping transition, the mean transition period was 10.5 days. A transition dosing algorithm was used in 10 patients (27.0%). At one year, 78.4% of the patients remained persistent on inhaled iloprost and 81.1% were free of clinical worsening. In selected patients on background oral PAH therapy, transitioning from parenteral prostacyclin to inhaled iloprost appears safe and feasible and is associated with long-term success. Further study is needed to define the optimal patient selection criteria and transition algorithm.

Pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a chronic and progressive disease leading to right heart failure and ultimately death if untreated. The first classification of PH was proposed in 1973. In 2008, the fourth World Symposium on PH held in Dana Point (California, USA) revised previous classifications. Currently, PH is devided into five subgroups. Group 1 includes patients suffering from idiopathic or familial PAH with or without germline mutations. Patients with a diagnosis of PAH should systematically been screened regarding to underlying mutations of BMPR2 gene (bone morphogenetic protein receptor type 2) or more rarely of ACVRL1 (activine receptor-like kinase type 1), ENG (endogline) or Smad8 genes. Pulmonary veno occusive disease and pulmonary capillary hemagiomatosis are individualized and designated as clinical group 1'. Group 2 'Pulmonary hypertension due to left heart diseases' is divided into three sub-groups: systolic dysfonction, diastolic dysfonction and valvular dysfonction. Group 3 'Pulmonary hypertension due to respiratory diseases' includes a heterogenous subgroup of respiratory diseases like PH due to pulmonary fibrosis, COPD, lung emphysema or interstitial lung disease for exemple. Group 4 includes chronic thromboembolic pulmonary hypertension without any distinction of proximal or distal forms. Group 5 regroup PH patients with unclear multifactorial mechanisms. Invasive hemodynamic assessment with right heart catheterization is requested to confirm the definite diagnosis of PH showing a resting mean pulmonary artery pressure (mPAP) of ≥ 25 mmHg and a normal pulmonary capillary wedge pressure (PCWP) of ≤ 15 mmHg. The assessment of PCWP may allow the distinction between pre-capillary and post-capillary PH (PCWP > 15 mmHg). Echocardiography is an important tool in the management of patients with underlying suspicion of PH. The European Society of Cardiology and the European Respiratory Society (ESC-ERS) guidelines specify its role, essentially in the screening proposing criteria for estimating the presence of PH mainly based on tricuspid regurgitation peak velocity and systolic artery pressure (sPAP). The therapy of PAH consists of non-specific drugs including oral anticoagulation and diuretics as well as PAH specific therapy. Diuretics are one of the most important treatment in the setting of PH because right heart failure leads to fluid retention, hepatic congestion, ascites and peripheral edema. Current recommendations propose oral anticoagulation aiming for targeting an International Normalized Ratio (INR) between 1.5-2.5. Target INR for patients displaying chronic thromboembolic PH is between 2–3. Better understanding in pathophysiological mechanisms of PH over the past quarter of a century has led to the development of medical therapeutics, even though no cure for PAH exists. Several specific therapeutic agents were developed for the medical management of PAH including prostanoids (epoprostenol, trepoprostenil, iloprost), endothelin receptor antagonists (bosentan, ambrisentan) and phosphodiesterase type 5 inhibitors (sildenafil, tadalafil). This review discusses the current state of art regarding to epidemiologic aspects of PH, diagnostic approaches and the current classification of PH. In addition, currently available specific PAH therapy is discussed as well as future treatments.

Combination therapy in pulmonary arterial hypertension

Many potential therapeutic options are now available for patients with pulmonary arterial hypertension. Interest has emerged in using therapies in various combinations. Retrospective experience has suggested that this approach is common and can be efficacious. Data are emerging supporting the benefit of combination therapy; however, limitations and questions remain about this strategy. This report reviewed the rationale for combination therapy and summarized the results from clinical trials.

Pulmonary hypertension: Hemodynamic evaluation. Updated Recommendations of the Cologne Consensus Conference 2011

The 2009 European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension have been adopted for Germany. The guidelines contain detailed recommendations for the diagnosis of pulmonary hypertension. However, the practical implementation of the European Guidelines in Germany requires the consideration of several country-specific issues and already existing novel data. This requires a detailed commentary to the guidelines, and in some aspects an update already appears necessary. In June 2010, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany. This conference aimed to solve practical and controversial issues surrounding the implementation of the European Guidelines in Germany. To this end, a number of working groups was initiated, one of which was specifically dedicated to the invasive hemodynamic evaluation of pulmonary hypertension. This manuscript describes in detail the results and recommendations of the working group which were last updated in October 2011.

Treatment of pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a chronic progressive disease of the pulmonary vasculature characterized by elevated pulmonary arterial pressure and secondary right ventricular failure. PAH is considered a life-threatening condition unless treated. This article provides a comprehensive review of controlled and uncontrolled trials to define the risk-benefit for different therapeutic options of this clinical disorder. Relevant published articles were identified through searches of the National Center for Biotechnology PubMed database. All therapeutic measures for PAH were discussed. Six drugs have been approved in the United States for the treatment of PAH. Extensive medical advancement has been achieved in treatment of PAH. However, none of the approved therapies have shown ability to cure the disease. New research should be performed to develop promising new therapies.

Clinical trials with endothelin receptor antagonists: what went wrong and where can we improve?

In the early 1990s, within three years of cloning of endothelin receptors, orally active endothelin receptor antagonists (ERAs) were tested in humans and the first clinical trial of ERA therapy in humans was published in 1995. ERAs were subsequently tested in clinical trials involving heart failure, pulmonary arterial hypertension, resistant arterial hypertension, stroke/subarachnoid hemorrhage and various forms of cancer. The results of most of these trials - except those for pulmonary arterial hypertension and scleroderma-related digital ulcers - were either negative or neutral. Problems with study design, patient selection, drug toxicity, and drug dosing have been used to explain or excuse failures. Currently, a number of pharmaceutical companies who had developed ERAs as drug candidates have discontinued clinical trials or further drug development. Given the problems with using ERAs in clinical medicine, at the Twelfth International Conference on Endothelin in Cambridge, UK, a panel discussion was held by clinicians actively involved in clinical development of ERA therapy in renal disease, systemic and pulmonary arterial hypertension, heart failure, and cancer. This article provides summaries from the panel discussion as well as personal perspectives of the panelists on how to proceed with further clinical testing of ERAs and guidance for researchers and decision makers in clinical drug development on where future research efforts might best be focused.

Current pathophysiological concepts and management of pulmonary hypertension

Pulmonary hypertension (PH), increasingly recognized as a major health burden, remains underdiagnosed due mainly to the unspecific symptoms. Pulmonary arterial hypertension (PAH) has been extensively investigated. Pathophysiological knowledge derives mostly from experimental models. Paradoxically, common non-PAH PH forms remain largely unexplored. Drugs targeting lung vascular tonus became available during the last two decades, notwithstanding the disease progresses in many patients. The aim of this review is to summarize recent advances in epidemiology, pathophysiology and management with particular focus on associated myocardial and systemic compromise and experimental therapeutic possibilities. PAH, currently viewed as a panvasculopathy, is due to a crosstalk between endothelial and smooth muscle cells, inflammatory activation and altered subcellular pathways. Cardiac cachexia and right ventricular compromise are fundamental determinants of PH prognosis. Combined vasodilator therapy is already mainstay for refractory cases, but drugs directed at these new pathophysiological pathways may constitute a significant advance.

Pulmonary arterial hypertension: advances in pathophysiology and management

Pulmonary arterial hypertension (PAH) is a heterogeneous, hemodynamic, and pathophysiological state which is commonly found throughout the world, but the disease burden is greater in India and in other developing countries. It is a disease characterized by vascular obstruction and vasoconstriction leading to progressive increase in pulmonary vascular resistance and right ventricular failure. PAH is a progressive disorder carrying a poor prognosis; however, dramatic progress has occurred in our knowledge of its pathogenesis and consequently, its treatment over the last two decades. In this article, we attempt to provide an overview of the etiology, pathophysiology, and current therapeutic modalities in the treatment of PAH. Patients suspected to have PAH should be submitted to a battery of investigations which help in establishing the diagnosis, identifying the etiology, guiding in treatment and informing the prognosis. All patients should be considered for standard therapy with oxygen, anticoagulation, and diuretics for right heart failure. Oral calcium channel blockers should be used in patients with a favorable response to acute vasodilator challenge. Disease targeted therapies include prostacyclines, endothelin receptor blockers, and phosphodiesterase-5 inhibitors. A brief mention of new and potential therapeutic strategies is also included.

Pulmonary arterial hypertension: an update

Pulmonary arterial hypertension (PAH), defined as group 1 of the World Heart Organisation (WHO) classification of pulmonary hypertension, is an uncommon disorder of the pulmonary vascular system. It is characterised by an increased pulmonary artery pressure, increased pulmonary vascular resistance and specific histological changes. It is a progressive disease finally resulting in right heart failure and premature death. Typical symptoms are dyspnoea at exercise, chest pain and syncope; furthermore clinical signs of right heart failure develop with disease progression. Echocardiography is the key investigation when pulmonary hypertension is suspected, but a reliable diagnosis of PAH and associated conditions requires an intense work-up including invasive measurement by right heart catheterisation. Treatment includes general measures and drugs targeting the pulmonary artery tone and vascular remodelling. This advanced medical therapy has significantly improved morbidity and mortality in patients with PAH in the last decade. Combinations of these drugs are indicated when treatment goals of disease stabilisation are not met. In patients refractory to medical therapy lung transplantation should be considered an option.

Overview of current therapeutic approaches for pulmonary hypertension

There have been tremendous strides in the management of pulmonary hypertension over the past 20 years with the introduction of targeted medical therapies and overall improvements in surgical treatment options and general supportive care. Furthermore, recent data shows that the survival of those with pulmonary arterial hypertension is improving. While there has been tremendous progress, much work remains to be done in improving the care of those with secondary forms of pulmonary hypertension, who constitute the majority of patients with this disorder, and in the optimal treatment approach in those with pulmonary arterial hypertension. This article will review general and targeted medical treatment, along with surgical interventions, of those with pulmonary hypertension.

Endothelin receptor antagonists -- their role in pulmonary medicine

INTRODUCTION

Understanding of the function of endothelin-1 in the pathophysiology of endothelial disease, in particular pulmonary arterial hypertension (PAH), has paved the way for the development of endothelin-receptor antagonists (ERAs) and explains the leading role they now play in the treatment armamentarium for this disease.

BACKGROUND

Three active ERA drugs (bosentan, sitaxentan, ambrisentan) are currently approved for the treatment of PAH in France. Several randomised clinical trials have demonstrated their efficacy and safety in PAH.

PERSPECTIVES AND CONCLUSION

Besides its vasoconstrictor effect, endothelin-1 (ET-1) plays a pivotal role in cell proliferation and apoptosis. ERAs are innovative drugs potentially useful in some pulmonary disorders such as idiopathic pulmonary fibrosis or systemic sclerosis, even though the preliminary results published remain insufficient or controversial.

CONCLUSION

ERAs play a major role in the management of pulmonary vascular disease. Other drugs, still under study, could prove useful in the treatment of infiltrating pneumonias.

Pharmacoeconomic evidence of bosentan for pulmonary arterial hypertension

In this article, we review randomized controlled trials, open-label trials and pharmacoeconomic models of bosentan for the management of patients with pulmonary arterial hypertension. Bosentan consistently improves WHO functional class and quality of life, slows clinical worsening and is associated with improved survival compared with historical treatment. Although head-to-head trials are scarce, data directly comparing bosentan with sildenafil indicate no clinically significant differences between treatments as measured by the 6-min walk distance alone. Compared with historical care, bosentan treatment, over a 15-30-year period, increases the number of quality-adjusted life years (3.49 years). Economic modeling suggests that the cost-effectiveness of bosentan is similar to that of ambrisentan (US$43,725-57,778 per quality-adjusted life year), not as cost effective as sildenafil (at 20 mg three-times daily) and more cost effective than iloprost. More randomized controlled trials of longer duration are required to confirm the results from these economic models.