Treprostinil, a prostacyclin analogue, in pulmonary arterial hypertension associated with connective tissue disease

Pulmonary arterial hypertension associated with systemic sclerosis

Systemic sclerosis (SSc) is commonly complicated by pulmonary arterial hypertension (PAH), which is a leading cause of death in the SSc patient population. Owing to the fact that the risk of developing pulmonary hypertension is high, screening is important, although the optimal modality remains to be defined. Furthermore, despite recent advances in therapy for PAH, the response to these interventions in patients with PAH with SSc has been discouraging. The lack of clinical response to these therapies may merely reflect the limitations of traditionally employed PAH outcome measures in SSc-PAH patients or highlight the heterogeneity of the disease manifestations within SSc. Importantly, since extrapulmonary involvement of the GI tract and kidneys by SSc limit candidacy for lung transplantation, new therapies that target abnormal cellular proliferation in the pulmonary vasculature are currently under investigation and may be particularly relevant to SSc-PAH.

[Pulmonary arterial hypertension in systemic lupus erythematosus]

Pulmonary hypertension (PH) is a serious complication of connective tissue diseases. The prevalence of PH in systemic lupus erythematosus (SLE) ranges from 0.5 to 17.5%, depending on whether echocardiography or right heart catheterization is used as the gold standard for diagnosis. The recent guidelines for the diagnosis and treatment of pulmonary hypertension include several potential causes of PH in SLE, including: a primary vasculopathy similar to idiopathic pulmonary arterial hypertension (PAH); left heart diseases; post-thromboembolic disease; hypoxia and fibrosis resulting from interstitial lung disease; and the infrequent SLE-associated pulmonary veno-occlusive disease. The pathogenesis of PAH associated with lupus is yet unclear, but likely includes a role for the genetic background, the presence of antiphospholipid antibodies, and some level of endothelial dysfunction. The evolution of SLE-associated PH is highly variable and difficult to elicit because the published series have used heterogeneous inclusion criteria. Optimal therapeutic management of PAH associated with lupus is unclear because no dedicated randomized controlled trial is yet available. Treatment usually includes arterial pulmonary vasodilators and immunosuppressive agents when the patients have NYHA functional class II, III or IV dyspnea.

Management of pulmonary arterial hypertension in children

In this review we discuss the new anti- Pulmonary Arterial Hypertension [PAH] drugs and the available data on their use in paediatric PAH. Treatment of patients with PAH, children and adults, is aimed at a reduction of symptoms, survival and improvement of haemodynamics as well as exercise capacity. PAH may reflect significant different disease conditions in infants and children when compared to PAH in adults. In contrast to adult PAH, characterized mainly by idiopathic PAH and PAH associated with connective tissue disease, more than half of the cases of PAH in children are associated with congenital heart disease. Therefore, efficacy of PAH drugs in these diseases can not be extrapolated from that in adults with PAH.

Pulmonary hypertension in systemic sclerosis

OBJECTIVES

To discuss the clinical subtypes, pathogenesis, pathology, diagnostic evaluation, treatment options, and prognosis of pulmonary hypertension in systemic sclerosis (SSc-PH) and highlight its fundamental differences from idiopathic pulmonary arterial hypertension (IPAH).

METHODS

A Medline search for articles published between January 1969 and June 2010 was conducted using the following keywords: scleroderma, systemic sclerosis, pulmonary hypertension, pulmonary arterial hypertension, pulmonary veno-occlusive disease, pathogenesis, pathology, investigation, treatment, and prognosis. The essential differences from IPAH in pathogenesis and histopathologic findings were highlighted and the limitations of some of the investigations used were emphasized. The differences in response to currently accepted therapy and prognosis were also reviewed.

RESULTS

In scleroderma, pulmonary hypertension can be present in isolation or along with interstitial lung disease and left heart disease. In SSc-PH, the unique histopathologic findings in the lungs include intimal fibrosis, absence of plexiform lesions, and a high prevalence of pulmonary veno-occlusive disease-like lesions. Both "6-minute walk test" and NT-proBNP have their limitations in the evaluation of SSc-PH. For treatment, calcium channel blockers are ineffective and anticoagulation should be used with caution. Currently approved therapies are not as effective and prognosis is much worse in SSc-PH compared with IPAH.

CONCLUSIONS

SSc-PH is a complex condition with poorer response to therapy and worse outcome compared with that of IPAH. Recent findings have shed some light about the pathophysiology and pathogenesis of SSc-PH. Further research in this area is warranted to better understand the complex pathogenesis and devise better therapeutic strategies.

Subcutaneous treprostinil in pulmonary arterial hypertension: Practical considerations

Treprostinil, which is available for subcutaneous (SC) and intravenous (IV) administration, has demonstrated efficacy in increasing exercise capacity, reducing signs and symptoms of pulmonary arterial hypertension (PAH), and improving cardiopulmonary hemodynamics in patients with PAH; however, the infusion site pain commonly experienced with SC treprostinil has limited its use. Prospective and observational clinical studies have shown that the dose of SC treprostinil can be escalated at a higher rate than described in early clinical trials to achieve symptom relief, in part because of favorable tolerability of treatment and the apparent dose independence of site pain. In addition, pain management protocols that include non-pharmacologic and pharmacologic (i.e., topical and systemic) approaches provide analgesic relief from infusion site pain. With experience, physicians and patients have recognized that some infusion sites are better than others, and the frequency of site rotation can be reduced to improve tolerability. Dosing to achieve rapid onset of efficacy and proactively managing infusion site pain enhance the likelihood for a patient with PAH to maintain and derive benefit from SC treprostinil therapy.

Validation of the 6 min walk test according to the OMERACT filter: a systematic literature review by the EPOSS-OMERACT group

OBJECTIVE

To assess the validity of the 6 min walk test (6MWT) in pulmonary arterial hypertension secondary to systemic sclerosis (PAH-SSc) according to the OMERACT filter.

METHODS

A systematic literature search was conducted from 1966 through June 2009. The assessment of validation of the 6MWT was based on the OMERACT filter criteria with the domains 'truth', 'discrimination' and 'feasibility'.

RESULTS

From the 57 articles identified, 9 (16%) were analysed. The 6MWT had face validity as it has been accepted by the registration agencies as a surrogate of PAH-SSc. It was sensitive to change in response to therapy, with effect sizes ranging from 0.30 to 1.37 with a parallel variation of haemodynamic parameters measured by right heart catheterisation. Feasibility was also validated. Content validity was not confirmed as this test was not specific for PAH-SSc. There was some evidence that 6MWT might meet criterion/construct validity, reproducibility and sensitivity to change over time, but insufficient data were provided to fully validate these components.

CONCLUSIONS

Current evidence suggests partial validation of the 6MWT in PAH-SSc according to the OMERACT filter. Further dedicated studies are needed to validate completely the 6MWT in PAH-SSc, taking into account the comorbidities interfering with the 6MWT.

Pharmacotherapy of systemic sclerosis

IMPORTANCE OF THE FIELD

Systemic sclerosis (SSc) is an uncommon autoimmune disease with variable degrees of fibroproliferation in blood vessels and certain organs of the body. There is currently no cure. The purpose of this article is to review the current literature regarding pathogenesis and treatment of complications of SSc.

AREAS COVERED IN THIS REVIEW

All available articles regarding research related to SSc pathogenesis and treatment listed in the PubMed database were searched; relevant articles were then reviewed and used as sources of information for this review.

WHAT THE READER WILL GAIN

This review attempts to highlight for the reader some current thought regarding mechanisms of SSc pathogenesis and how autoimmunity relates to vascular changes and fibrogenesis of the disease, as well as providing a review of results of completed clinical trials and current ongoing clinical trials that address organ-specific or global therapies for this disease. This can aid physicians who provide medical care for patients with SSc.

TAKE HOME MESSAGE

SSc is a complex autoimmune disease, the pathogenesis of which, although not completely understood, is under active study; new insights into pathogenesis are continually being discovered. Although there is no effective disease-modifying treatment for patients with SSc, quality of life, morbidity and mortality can be improved by using targeted therapy directed at affecting the consequences of damage to lungs, blood vessels, kidneys and the gastrointestinal tract. Innovative approaches to treating SSc are under intense investigation.

Diagnosis and management of pulmonary hypertension in systemic sclerosis

Patients with systemic sclerosis (SSc) can develop pulmonary hypertension (PH; mean pulmonary artery pressure >/= 25 mm Hg) caused by pulmonary arterial hypertension (PAH), left ventricular disease, or pulmonary fibrosis. PAH is a pulmonary vascular disease, the diagnosis of which requires pulmonary capillary wedge pressure less than 15 mm Hg, pulmonary vascular resistance greater than 3 Wood Units, and exclusion of thromboembolism and parenchymal lung disease. Molecular mechanisms underlying PAH-SSc include activation of inflammatory and fibrogenic pathways in the vasculature and right ventricle. Circulating autoantibodies trigger endothelial damage and fibroblast activation. PAH most commonly occurs as a late complication in patients with limited cutaneous disease and anticentromere antibodies. Although echocardiography is a useful screening tool, heart catheterization is required to diagnose PAH before initiating therapy. Prognosis and therapeutic response are worse in PAH-SSc than in other PAH categories (median survival, 1-3 y). Approved therapies include prostacyclins, endothelin antagonists, and phosphodiesterase type 5 inhibitors. Research is needed to define disease mechanisms and develop effective therapies.

[Pulmonary arterial hypertension in collagenoses]

Pulmonary arterial hypertension is a rare disease of small pulmonary arteries of unknown origin characterised by endothelial dysfunction and cellular proliferation throughout all vessel layers, resulting in progressively elevated pulmonary arterial resistance with increasing right heart strain and finally right heart failure. The condition may develop in connective tissue diseases with variable frequency leading to a substantial worsening of prognosis. However, the spectrum of therapeutic options has broadened significantly in recent years. Several compounds have gained approval that act mainly as pulmonary vasodilators. Further drugs are under investigation, some of which target pulmonary vascular remodeling. Echocardiography remains the primary examination for disease detection. To classify pulmonary hypertension definite hemodynamic evaluation by means of right heart catheterisation and a thorough differential diagnosis are essential to provide the basis for further treatment. For differential therapy and assessment of follow-up profound knowledge is required, pointing to the need for close cooperation with specialised centres.

Brain natriuretic peptide in pulmonary arterial hypertension: biomarker and potential therapeutic agent

B-type natriuretic peptide (BNP) is a member of the natriuretic peptide family, a group of widely distributed, but evolutionarily conserved, polypeptide mediators that exert myriad cardiovascular effects. BNP is a potent vasodilator with mitogenic, hypertrophic and pro-inflammatory properties that is upregulated in pulmonary hypertensive diseases. Circulating levels of BNP correlate with mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) in patients with pulmonary arterial hypertension (PAH). Elevated plasma BNP levels are associated with increased mortality in patients with PAH and a fall in BNP levels after therapy is associated with improved survival. These findings have important clinical implications in that a noninvasive blood test may be used to identify PAH patients at high-risk of decompensation and to guide pulmonary vasodilator therapy. BNP also has several biologic effects that could be beneficial to patients with PAH. However, lack of a convenient method for achieving sustained increases in circulating BNP levels has impeded the development of BNP as a therapy for treating pulmonary hypertension. New technologies that allow transdermal or oral administration of the natriuretic peptides have the potential to greatly accelerate research into therapeutic use of BNP for cor pulmonale and pulmonary vascular diseases. This review will examine the basic science and clinical research that has led to our understanding of the role of BNP in cardiovascular physiology, its use as a biomarker of right ventricular function and its therapeutic potential for managing patients with pulmonary vascular disease.

Therapy for pulmonary arterial hypertension associated with systemic sclerosis

PURPOSE OF REVIEW

Systemic sclerosis is commonly complicated by pulmonary arterial hypertension (PAH-SSc) and is a leading cause of death in this population. We will review existing challenges and recent advances in the treatment of this disease.

RECENT FINDINGS

Traditionally employed outcome measures in pulmonary arterial hypertension research may not be applicable in PAH-SSc. Importantly, new therapies that target abnormal cellular proliferation in the pulmonary vasculature are currently under investigation and may be particularly relevant to PAH-SSc.

SUMMARY

Pulmonary arterial hypertension complicating systemic sclerosis occurs commonly and portends a poor prognosis. However, recent advances in our understanding of the disease in the context of systemic sclerosis may lead to novel diagnostic and therapeutic strategies that will ultimately improve quality of life and survival in this population.

Comparison of baseline characteristics and survival between patients with idiopathic and connective tissue disease-related pulmonary arterial hypertension

BACKGROUND

Both idiopathic pulmonary arterial hypertension (IPAH) and pulmonary arterial hypertension (PAH) related to connective tissue diseases (CPAH) are classified in the group of PAH disorders. However, CPAH has a particularly worse prognosis than IPAH. Few studies have compared the clinical, functional and hemodynamic profiles of IPAH and CPAH.

METHODS

We performed a retrospective cohort study of patients with IPAH or CPAH. Demographic characteristics, functional status (FE), pulmonary function test and hemodynamic values at the time of diagnosis were compared between the two etiologies. Global cumulative survival rates free from transplantation (SFT) and survival according to date of diagnosis were analyzed.

RESULTS

Despite similar PAH severity, patients with CPAH showed a more severe baseline impairment of 6-minute walking test (6MWT) (307 +/- 116 m vs 378 +/- 101 m) and diffusion capacity of the lung for carbon monoxide (DLCO) (57 +/- 25% vs 75 +/- 30% of predicted) than IPAH (p < 0.01). Survival rates at 1, 3 and 5 years of follow-up were 87%, 71% and 63% for IPAH, and 70%, 53% and 42% for CPAH, respectively (p < 0.05). IPAH showed better survival when treatment was started after Year 2000 (p = 0.01). However, CPAH showed a poorer prognosis than IPAH in the more recent era (p < 0.05). CPAH (hazard ratio [HR] = 2.03), DLCO <80% (HR = 1.98) and treatment before Year 2000 (HR = 2.27) were associated with an independent increased risk of death or transplantation.

CONCLUSIONS

Despite similar functional and hemodynamic severity, patients with CPAH showed a more severe baseline impairment of 6MWT and DLCO and worse overall prognosis than IPAH. Both IPAH and CPAH survival improved in the current era. Nevertheless, CPAH still showed a poorer prognosis than IPAH.

Pulmonary arterial hypertension: the most devastating vascular complication of systemic sclerosis

Pulmonary arterial hypertension (PAH) is a devastating vascular complication of a number of CTDs. In patients with SSc, PAH has a dramatic impact on prognosis and survival and is the single most common cause of disease-related death.Yearly echocardiographic screening for PAH is recommended in patients with SSc. If suspected, confirmation of PAH diagnosis by right heart catheterization is necessary. Treatment goals for patients with PAH associated with SSc (PAH-SSc) aim to slow disease progression and improve quality of life. Some measures used to gauge the effect of treatment in patients with PAH-SSc remain to be fully validated; the 6-min walk distance, for example, is a simple and reproducible means of assessing exercise capacity, but there exists a need to understand what constitutes a clinically relevant change in this specific patient population. Currently, pharmacological intervention in PAH-SSc may target one or more of three pathophysiological pathways in PAH. The prostacyclin analogue epoprostenol has been shown to improve exercise capacity and haemodynamics in PAH-SSc patients and similar data are available from smaller studies on trepostinil and iloprost. The dual endothelin receptor antagonist bosentan has been shown to improve exercise capacity and haemodynamics in PAH-SSc, and similar data have been obtained in small numbers of patients treated with the endothelin receptor A antagonists sitaxsentan and ambrisentan. Impaired production of nitric oxide may be addressed by inhibiting phosphodiesterase type-5 with sildenafil or possibly tadalafil. Combinations of multiple targeted therapies may be beneficial to this patient population.

EULAR recommendations for the treatment of systemic sclerosis: a report from the EULAR Scleroderma Trials and Research group (EUSTAR)

PURPOSE

The optimal treatment of systemic sclerosis (SSc) is a challenge because the pathogenesis of SSc is unclear and it is an uncommon and clinically heterogeneous disease affecting multiple organ systems. The aim of the European League Against Rheumatism (EULAR) Scleroderma Trials and Research group (EUSTAR) was to develop evidence-based, consensus-derived recommendations for the treatment of SSc.

METHODS

To obtain and maintain a high level of intrinsic quality and comparability of this approach, EULAR standard operating procedures were followed. The task force comprised 18 SSc experts from Europe, the USA and Japan, two SSc patients and three fellows for literature research. The preliminary set of research questions concerning SSc treatment was provided by 74 EUSTAR centres.

RESULTS

Based on discussion of the clinical research evidence from published literature, and combining this with current expert opinion and clinical experience, 14 recommendations for the treatment of SSc were formulated. The final set includes the following recommendations: three on SSc-related digital vasculopathy (Raynaud's phenomenon and ulcers); four on SSc-related pulmonary arterial hypertension; three on SSc-related gastrointestinal involvement; two on scleroderma renal crisis; one on SSc-related interstitial lung disease and one on skin involvement. Experts also formulated several questions for a future research agenda.

CONCLUSIONS

Evidence-based, consensus-derived recommendations are useful for rheumatologists to help guide treatment for patients with SSc. These recommendations may also help to define directions for future clinical research in SSc.

Limitations to the 6-minute walk test in interstitial lung disease and pulmonary hypertension in scleroderma

OBJECTIVE

To determine factors that influence 6-minute walk distance (6MWD) in patients with scleroderma (systemic sclerosis, SSc)-interstitial lung disease (ILD), SSc-pulmonary hypertension (PH), and idiopathic pulmonary fibrosis (IPF).

METHODS

We retrospectively evaluated all patients with SSc or IPF who performed a 6-minute walk test (6MWT) at a university hospital between 1999 and 2003. Chi-square, ANOVA, simple linear regression, and backwards elimination multivariable regressions were performed.

RESULTS

Forty-eight consecutive IPF patients with 6MWT were compared to 33 patients with SSc-ILD, 13 with SSc-PH, 19 with both SSc-ILD and SSc-PH (SSc-Both), and 15 with SSc without ILD or PH (SSc-Neither). Mean 6MWD did not differ between groups. Limitations to 6MWT trended toward dyspnea in IPF and lower extremity pain in SSc. SSc-Both had dyspnea limitation more than other SSc subgroups (p = 0.017). Percentage predicted forced vital capacity (FVC%) and percentage predicted carbon monoxide diffusing capacity (DLCO%) were more strongly predictive of 6MWD in IPF than in SSc; however, exclusion of SSc subjects with pain limitation improved the predictive value. Significant correlates of 6MWD in multivariable analysis differed between subgroups.

CONCLUSION

Pain limitations confound the utility of the 6MWT, particularly in SSc. Pain may cause failure to reach a dyspnea limitation during 6MWT, especially in SSc patients without both ILD and PH. Correlates of 6MWD differ between SSc subgroups and IPF; therefore, the 6MWT distance is not always reflective of the same physiological process. 6MWT interpretation should include consideration of vascular, pulmonary, and musculoskeletal exercise limitations.

Connective tissue disease-associated pulmonary arterial hypertension in the modern treatment era

RATIONALE

Pulmonary arterial hypertension in association with connective tissue disease (CTD-PAH) has historically had a poor prognosis, with a 1-year survival rate among patients with systemic sclerosis-associated pulmonary arterial hypertension (SSc-PAH) of 45%. However, more therapies have become available.

OBJECTIVES

To investigate the survival and characteristics of all patients diagnosed with CTD-PAH in the U.K. pulmonary hypertension service.

METHODS

National registry of all incident cases of CTD-PAH diagnosed consecutively between January 2001 and June 2006.

MEASUREMENTS AND MAIN RESULTS

Patients with CTD-PAH (429; 73% SSc-PAH) were diagnosed by a catheter-based approach. One- and 3-year survival rates were 78 and 47% for patients with isolated SSc-PAH. Survival was worse for those with respiratory disease-associated SSc-PAH (3-yr survival, 28%; P = 0.005) whereas survival among patients with exercise-induced SSc-PAH was superior (3-yr survival, 86%; P = < 0.001). Age, sex, mixed venous oxygen saturation, and World Health Organization functional class were independent predictors of survival in isolated SSc-PAH. Nineteen percent of patients with exercise-induced SSc-PAH and 39% of patients with isolated SSc-PAH who were in functional classes I and II had evidence of disease progression. The prevalence of diagnosed SSc-PAH is 2.93 per 1 million. The 3-year survival rate of 75% for those with pulmonary arterial hypertension associated with systemic lupus erythematosus (SLE-PAH) was significantly better than that for patients with SSc-PAH (P = 0.01).

CONCLUSIONS

Survival of patients with SSc-PAH in the modern treatment era is better than in historical series. A significant proportion of patients with mild functional impairment or exercise-induced SSc-PAH have evidence of disease progression. Survival of patients with respiratory disease-associated pulmonary hypertension is inferior. SLE-PAH has a better prognosis than SSc-PAH.

Health-related quality of life and patient-reported outcomes in pulmonary arterial hypertension

Advances in our understanding of the basic pathophysiology of pulmonary arterial hypertension (PAH) has led to an expanding number of therapeutic options. The ultimate goals of therapy are to lengthen survival while improving symptoms and quality of life. A wealth of research in other conditions has established health-related quality of life (HRQoL) to be an important clinical endpoint. Until recently, however, little was known about HRQoL in PAH, and how best to measure it. Over the past few years, several studies have begun contributing to this growing area of research. Instruments used to assess HRQoL have varied between studies. The extent to which these instruments are valid in PAH depend on their specific measurement properties. In this article, we provide an overview of the different types of patient-reported outcomes (PROs) used in PAH, focusing in particular on the measurement of HRQoL. In the process, we review the current literature on HRQoL in PAH, summarize the available data from randomized controlled trials, and discuss the implications of these findings on future research. Despite significant progress, the study of HRQoL in PAH remains a nascent field relative to other conditions. As the use of PROs continues to increase, additional work will be needed to begin standardizing the reporting and interpretation of such outcomes in future clinical trials.

Systemic sclerosis: an update for clinicians

Recent advances in the management of systemic sclerosis highlight the importance of early diagnosis and assessment, before irreversible tissue injury has occurred. This review will discuss diagnosis, subtyping, and the major clinical features and their management.

Long-term effects of bosentan on quality of life, survival, safety and tolerability in pulmonary arterial hypertension related to connective tissue diseases

OBJECTIVES

This study investigated the long-term effects of bosentan, an oral endothelin ET(A)/ET(B) receptor antagonist, in patients with pulmonary arterial hypertension (PAH) exclusively related to connective tissue diseases (CTD).

METHODS

A total of 53 patients with PAH related to connective tissue diseases (PAH-CTD) in World Health Organization (WHO) functional class III received bosentan 62.5 mg twice a day for 4 weeks and then 125 mg twice a day for 44 weeks in this open non-comparative study. Assessments at weeks 16 and 48 included WHO class, clinical worsening, quality of life (Short-Form Health Survey (SF-36) and health assessment questionnaire (HAQ) modified for scleroderma), and survival (week 48 only). Safety and tolerability were monitored throughout the study.

RESULTS

At week 48, WHO class improved in 27% of patients (95% CI 16-42%) and worsened in 16% (95% CI 7-29%). Kaplan-Meier estimates were 68% (95% CI 55-82%) for absence of clinical worsening and 92% (95% CI 85-100%) for survival. Overall changes in quality of life were minimal. There were no unexpected side effects observed during the study.

CONCLUSIONS

In most patients, bosentan was associated with improvement or stability of clinical status. The 92% estimate for survival at 48 weeks is a significant achievement in this patient population.

Treatment of complications associated with systemic sclerosis

PURPOSE

Current and emerging drug therapy options for patients suffering from the complications of systemic sclerosis are presented.

SUMMARY

Systemic sclerosis is a devastating and rare, chronic, autoimmune disease and is characterized by various disease complications due to skin thickening, vascular damage, and inflammation affecting numerous organs. There are two major subtypes of systemic sclerosis: limited cutaneous scleroderma and diffuse cutaneous scleroderma. Patients suffer from Raynaud's phenomenon, skin changes, musculoskeletal changes, gastrointestinal complications, pulmonary complications, scleroderma renal crisis, and dryness of the eyes and mouth. Currently, there is no cure for systemic sclerosis, but research is focusing on decreasing the progression and symptoms of this disease. Raynaud's phenomenon is the temporary vasoconstriction of the small vessels of the fingers, toes, tip of the nose, and earlobes. Skin thickening is the cardinal symptom of systemic sclerosis, with as many as 50% of patients developing digital ulcers. Care of these ulcers is crucial in the prevention of osteomyelitis and other infections. Malabsorption syndrome may also occur in patients, many of whom will eventually require parenteral nutrition to maintain their caloric needs. Pulmonary interstitial fibrosis and pulmonary arterial hypertension are additional serious complications of systemic sclerosis. The use of prostacyclin analogues, phosphodiesterase inhibitors, calcium-channel blockers, cyclophosphamide, bosentan, and other agents has been investigated in patients suffering from the complications of systemic sclerosis.

CONCLUSION

Systemic sclerosis is characterized by various circulatory, dermatological, gastrointestinal, musculoskeletal, pulmonary, and renal complications. Although there is no cure for systemic sclerosis, management of its associated complications can help improve patients' quality of life.

Current drug therapy for scleroderma and secondary Raynaud's phenomenon: evidence-based review

(1) Scleroderma and secondary Raynaud's phenomenon are frequently associated with increased morbidity for which no specific standardised treatment guidelines exist. (2) Current therapies for scleroderma target the immune system, with the goal of reducing inflammation and secondary tissue injury and fibrosis. Therapy targeting underlying vascular disease is designed to improve the symptoms of Raynaud's phenomenon and to reduce ischemic injury to involved organs. (3) Few controlled trials of therapy used for scleroderma are completed, and current treatments are largely based on organ-specific therapy and uncontrolled case series suggesting disease modification. (4) Recent randomised, controlled trials in scleroderma demonstrate promising results in the treatment of interstitial lung disease with cyclophosphamide, and vascular disease of the lungs and digits with endothelin receptor antagonists, the phosphodiesterase inhibitor sildenafil and prostacyclins, while trials with methotrexate show only modest benefit in controlling scleroderma-associated skin disease. (5) Prostacyclins are a therapeutic option in patients with secondary Raynaud's phenomenon. Modest benefits have also been shown with alpha1-antagonists and calcium channel blockers, while the effect of ACE inhibitors has been variable. Some data suggest some benefits to the use of the phosphodiesterase inhibitor sildenafil, the serotonin uptake inhibitor fluoxetine and the angiotensin receptor inhibitor losartan.

Screening and therapy of pulmonary hypertension in systemic sclerosis

PURPOSE OF REVIEW

Systemic sclerosis is a major risk factor for the development of pulmonary arterial hypertension. Often this disease is far advanced by the time it is detected in the individual patient, severely impacting quality of life and survival.

RECENT FINDINGS

Therapeutic options available for patients with scleroderma-associated pulmonary arterial hypertension have increased significantly over the last few years, fueling our desire to improve early detection of disease.

SUMMARY

During the course of this manuscript I will review the literature examining approaches towards screening for scleroderma-associated pulmonary arterial hypertension. I will then discuss the most recent studies examining therapeutic options for patients with this disease.

Initial experience using continuous intravenous treprostinil to manage pulmonary arterial hypertension in patients with end-stage liver disease

Treprostinil is a prostacyclin analog and has been used on idiopathic pulmonary arterial hypertension (PAH). There is only limited clinical experience using treprostinil to manage PAH in patients with end-stage liver disease (ESLD). We report three ESLD patients with PAH, who were treated with continuous intravenous treprostinil. A 59-year-old woman with ESLD secondary to alcoholic hepatitis had portopulmonary hypertension with mean pulmonary arterial pressure (mPAP) of 44 mmHg and transpulmonary gradient (TPG) of 23 mmHg. Treprostinil at 45 ng/kg/min for 6 months decreased mPAP to 23 (TPG to 8). A 53-year-old man had ESLD secondary to alcoholic hepatitis with PAH caused by multiple pulmonary embolisms (mPAP of 32 and TPG of 23). Treprostinil at 36 ng/kg/min for 3 months decreased mPAP to 23 and TPG to 14. Both patients underwent uneventful liver transplantation. A 48-year-old man had ESLD secondary to hepatitis C and portopulmonary hypertension with mPAP of 60 and TPG of 44. Two years after intravenous treprostinil at 106 ng/kg/min, his mPAP decreased to 44 and TPG to 30. These results demonstrate that for a selected group of ESLD patients with PAH, a continuous intravenous infusion of treprostinil appears to be safe and effective.

Selective endothelin A receptor antagonism with sitaxsentan for pulmonary arterial hypertension associated with connective tissue disease

INTRODUCTION

Endothelin receptor antagonism has become an important component in the treatment of pulmonary arterial hypertension (PAH) associated with connective tissue disease (CTD). The purpose of this study was to analyse the safety and effectiveness of sitaxsentan, a selective antagonist of the ET(A) receptor, in a cohort of patients with PAH and CTD. Short-term clinical and haemodynamic effects and longer-term follow-up data are presented.

METHODS

A post hoc subgroup analysis was performed on 42 patients who had PAH associated with CTD, out of a group of 178 patients enrolled in a 12-week, double-blind, randomised clinical trial of sitaxsentan versus placebo. Data from 33 patients assigned to sitaxsentan 100 mg or 300 mg daily were pooled and compared with nine placebo-treated patients. There were 41 patients entered into the blinded extension study, in which all patients received either 100 mg or 300 mg sitaxsentan once daily.

RESULTS

Patients treated with sitaxsentan had a mean (SD) increase in 6 minute walk distance of 20 (5) m from baseline to week 12 (p = 0.037), whereas the placebo group had a decrease of 38 (84) m, resulting in a placebo-subtracted treatment effect of 58 m (p = 0.027). Parallel improvements in quality of life and haemodynamics were also observed. No patient discontinued their drug during the 12-week trial. In the blinded extension study (median treatment duration 26 weeks), more patients were in functional class I-II than in III-IV (p<0.001) at the end of the study compared with the start of active therapy. Elevation of hepatic transaminase levels occurred in two patients.

CONCLUSIONS

Sitaxsentan appears to be efficacious in patients with PAH associated with CTD.

Current therapies for pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a progressive disease of the pulmonary vasculature, characterized by relentless deterioration and death. Patients with PAH are known to be at increased risk for anesthetic complications and surgical morbidity and mortality. However, outcomes in patients have improved with the recent development of new drug therapies. The 3 major drug classes for treatment of PAH are prostanoids, endothelin-receptor antagonists, and phosphodiesterase-5 inhibitors. In this review, the authors provide an overview of each drug class, its mechanism of action, indications, and current supportive literature. Surgical and interventional treatments of PAH, including atrial septostomy, pulmonary thromboendarterectomy, and transplantation, are briefly reviewed, and the rationale, indications, and selection criteria for each are discussed. Although available medical and surgical therapies for PAH have improved patient outcomes, acute decompensated right heart failure (RHF) remains a common and challenging complication of PAH. The authors review this topic and provide an outline of the general pathophysiology of RHF and an approach to its management.

Lupus-associated pulmonary hypertension: long-term response to vasoactive therapy

INTRODUCTION

Pulmonary hypertension (PH) is a serious complication of lupus. The effectiveness of current vasoactive therapy has not been well described.

METHODS

Retrospective analysis of 12 patients with lupus-associated PH (age 43+/-10 years, mean+/-SD, all female) treated with pulmonary vasodilators.

RESULTS

At baseline, patients had severe PH: median six-minute walk distance (6MWD) 266 m (95% confidence interval [CI], 106 to 362); functional class III (n=7) and IV (n=5); mean pulmonary artery pressure (mPAP) 52 mmHg and cardiac index 2.23 L/min/m(2). Eight patients were started on epoprostenol and 2 each on bosentan or treprostinil. After a mean follow-up of 41+/-25 months, 5 patients were on combination therapy (3 epoprostenol plus bosentan, 1 treprostinil plus bosentan, 1 bosentan plus sildenafil) and 7 were on monotherapy (2 epoprostenol, 4 bosentan, 1 sildenafil); 6MWD increased by 139 m (95% CI, 36 to 259, p=0.007), 8 patients were functional class I or II and 4 were class III; right ventricular systolic pressure (RVSP) decreased by 22 mmHg (95% CI, 6 to 36; p=0.012), mPAP decreased by 18 mmHg (95% CI, 8 to 29; p=0.014), and cardiac index increased by 1.44 L/min/m(2) (95% CI, 0.76 to 2.08; p=0.016). There was no mortality or need for lung transplantation. Therapy was well tolerated.

CONCLUSIONS

Vasoactive therapy can achieve sustained clinical and hemodynamic improvement in lupus-associated PH.

Therapy of pulmonary arterial hypertension in systemic sclerosis: An update

Pulmonary arterial hypertension (PAH) affects 10% to 15% of patients with systemic sclerosis and is a major cause for disease-related morbidity and mortality. Over the past decade, significant progress has been made in the understanding of the pathophysiologic mechanisms underlying PAH. This progress led to the development of several new treatment options and, as a result, dramatically improved survival among this severely affected cohort. The outcome in patients with scleroderma-related PAH is much worse than that in patients with idiopathic PAH, and unfortunately only a few studies have assessed treatment and outcome among patients suffering from connective tissue disease-related PAH. In recent years, publications of connective tissue disease subgroup analysis from large trials in PAH have emerged. We review the current treatment options for PAH and the evidence for their use in scleroderma-related PAH.

Treprostinil potentiates the positive inotropic effect of catecholamines in adult rat ventricular cardiomyocytes

BACKGROUND AND PURPOSE

Prostanoids have been shown to improve exercise tolerance, hemodynamics and quality of life in patients with pulmonary arterial hypertension (PAH). We investigated whether treprostinil exerts direct contractile effects on cardiomyocytes that may explain partly the beneficial effects of these drugs.

EXPERIMENTAL APPROACH

Ventricular cardiomyocytes from adult rats were paced at a constant frequency of 0.5 to 2.0 Hz and cell shortening was monitored via a cell edge detection system. Twitch amplitudes, expressed as percent cell shortening of the diastolic cell length, and maximal contraction velocity, relaxation velocity, time to peak of contraction and time to reach 50% of relaxation were analyzed.

KEY RESULTS

Treprostinil (0.15 - 15 ng ml(-1)) slightly increased contractile dynamics of cardiomyocytes at clinically relevant concentrations. However, the drug significantly improved cell shortening of cardiomyocytes in the presence of isoprenaline, a beta-adrenoceptor agonist. Treprostinil exerted this effect at all beating frequencies under investigation. Treprostinil mimicked this potentiating effect in a Langendorff preparation as well. The potentiating effect of treprostinil on isoprenaline-dependent cell shortening was no longer seen after phosphodiesterase inhibition. Long-term cultivation of cardiomyocytes with treprostinil did not modify load free cell shortening of these cells, but reduces the duration of contraction.

CONCLUSIONS AND IMPLICATIONS

We conclude that the clinically used prostanoid treprostinil potentiates the positive inotropic effects of catecholamines in adult ventricular cardiomyocytes. This newly described effect may contribute to the beneficial clinical effects of prostanoids in patients with PAH.

Prostanoid therapy for pulmonary arterial hypertension

Epoprostenol and the structurally related compounds treprostinil, iloprost, and beraprost are collectively referred to as prostanoids. The discovery of epoprostenol in 1976 and unequivocal demonstration of its efficacy in 1996 dramatically altered the approach to therapy for pulmonary arterial hypertension (PAH). Development of prostanoids available through multiple routes of administration and the discovery and development of other agents acting through alternative pathways continue to expand the array of therapeutic options. The use of prostanoids in combination with other PAH drugs and for treating pulmonary hypertensive disorders outside of the PAH classification are areas of ongoing research.

Quality of life in pulmonary arterial hypertension: improvement and maintenance with bosentan

BACKGROUND

Bosentan (an oral dual endothelin receptor antagonist) improves symptoms and cardiac hemodynamics and reduces clinical worsening in patients with pulmonary arterial hypertension (PAH). The VITAL study assessed the effect of bosentan on quality of life in patients with WHO Functional Class III or IV PAH (idiopathic or associated with connective tissue diseases).

METHODS

Quality of life was assessed prospectively using the MOS SF-36 and AQOL questionnaires. Baseline readings and scores at 3 and 6 months were collected, in addition to other efficacy and safety data.

RESULTS

Among the 177 study patients, SF-36 scores were significantly improved at 3 months in the domains of physical functioning (27.3 to 34.8; p < 0.0001), role-physical (16.6 to 30.9; p < 0.0001), vitality (35.2 to 41.1; p = 0.0003), social functioning (48.0 to 58.6; p < 0.0001), mental health (64.2 to 72.0; p = 0.005) and role-emotional (44.8 to 58.1; p = 0.001). Improvements were seen in all etiologic sub-groups and were maintained in patients who remained on bosentan. An improvement in AQOL measures at 3 months was also noted for patients with baseline WHO Functional Class III.

CONCLUSIONS

Bosentan significantly improves quality of life in patients with idiopathic PAH or PAH associated with connective tissue diseases.

[Pulmonary arterial hypertension in collagenoses: clinical features, epidemiology, pathogenesis, diagnosis and treatment]

Pulmonary arterial hypertension (PAH) is a severe vasculopathy, which is characterised by progressive narrowing and obliteration of the pulmonary arterioles and increased endothelin-1 levels. The increase of vascular resistance in the lung vessels leads to chronic pressure overload and to right heart failure, if untreated. PAH often occurs in association with rheumatic-inflammatory diseases (e.g., in 15% of patients with systemic sclerosis (SSc), especially in the limited form or in CREST patients) and determines their prognosis: in advanced stages, untreated patients die within a short period. Therefore all SSc patients, particularly the newly diagnosed ones, should be screened for PAH with echocardiography. If PAH is suspected, a right heart catheter should be performed, and if PAH is confirmed, adequate treatment should be initiated. While few years ago lung transplantation was the only option for patients with severe PAH, in recent years enormous progress was seen in drug treatment. Today prostanoids (Ventavis) and the endothelin receptor antagonist bosentan (Tracleer) are available for patients with PAH in WHO/NYHA stage III: they have substantially improved the prognosis of PAH in the last years. Since few months, also the phosphodiesterase inhibitor sildenafil (Revatio) is available. The combination of drugs with different mode of action will likely further improve the prognosis of PAH patients.

Pharmacologic treatment for pulmonary arterial hypertension

PURPOSE OF REVIEW

Pulmonary arterial hypertension (PAH) has been a disease with limited treatment options and poor prognosis. This article reviews the recent advances that took place in the medical management of PAH.

RECENT FINDINGS

Sildenafil is a type 5 cGMP-specific phosphodiesterase inhibitor originally developed to treat erectile dysfunction. Multiple uncontrolled and randomized controlled trials have proven that it is useful in the treatment of PAH and it was approved by the US Food and Drug Administration. The switch from continuous intravenous infusion of epoprostenol to subcutaneous infusion of treprostinil has been proven feasible and safe. Bosentan has been shown effective as a monotherapy and it also improves survival in patients with functional classes III and IV. In smaller clinical trials bosentan has improved symptoms in different forms of PAH. Combinations of drugs of different classes such as prostanoids, endothelin receptor blockers and sildenafil are tested, and such a strategy improves both symptoms and survival. Animal models and anecdotal clinical experience suggest the possibility of using imatinib mesylate in PAH.

SUMMARY

With the approval of sildenafil, treatment options for this difficult disease have improved significantly. Combinations of drugs of different groups are promising and need further exploration.

Six-Minute Walk Test for the Evaluation of Pulmonary Disease Severity in Scleroderma Patients

BACKGROUND

Pulmonary involvement is the leading cause of systemic sclerosis (SSc)-related deaths. A simple test to evaluate exercise capacity is the 6-min walk test (6MWT), and the walk distance is used as a primary outcome in clinical trials. Hemoglobin desaturation during a 6MWT is predictive of mortality in patients with primary pulmonary hypertension. Our objectives were to evaluate the walk distance and resting oxygen saturation - oxygen saturation after the 6-min period (DeltaSat) during the 6MWT in patients with SSc, and to establish correlations between the 6MWT results and other clinical variables.

METHODS

We analyzed 110 SSc patients. DeltaSat was defined as a fall of end-of-test saturation >or= 4%. Clinical and demographic data were collected. All the patients were submitted to chest radiographs and high-resolution CT (HRCT) and underwent pulmonary function testing and echocardiography, and the presence of autoantibodies was determined.

RESULTS

The variables associated with a walk distance < 400 m (p < 0.05) were age, dyspnea index, fibrosis on radiography, pulmonary arterial systolic pressure (PASP) >or= 30 mm Hg, and desaturation. The variables associated with DeltaSat (p < 0.05) were age, positive anti-Scl-70 autoantibody, dyspnea index, fibrosis on radiography, FVC < 80% of predicted, PASP >or= 30 mm Hg, and ground-glass or reticular opacities on HRCT. In the multivariate logistic regression analysis, three variables were significant when tested with walk distance: age, race, and dyspnea index; four variables were significant when tested with DeltaSat: age, dyspnea index, positive anti-Scl-70 autoantibody, and FVC < 80% of predicted.

CONCLUSIONS

Desaturation during a 6MWT provides additional information regarding severity of disease in scleroderma patients with pulmonary manifestations.

Hypertension artérielle pulmonaire associée à la sclérodermie systémique

Pulmonary arterial hypertension (PAH) is a serious complication of systemic sclerosis (SSc) and a leading cause of death in patients with it. Recent publications suggest that a prevalence of 10-15% is likely. The prognosis remains poor compared to that of idiopathic PAH. WHO recommends annual echocardiography for PAH screening of patients with SSc. Right heart catheterization is necessary to confirm the diagnosis. Nevertheless, more than half of all SSc patients have symptoms classified as WHO functional class III or IV at diagnosis. Prostacyclin therapy, delivered via continuous intravenous infusion (epoprostenol), has been demonstrated to be effective in patients with severe PAH (both idiopathic and scleroderma-related). Prostacyclin analogs (such as treprostinil and iloprost) are other options. Bosentan is the first endothelin receptor antagonist approved in the EU for the treatment of PAH, both idiopathic and related to connective tissue diseases such as scleroderma, in patients in WHO functional class III. Sildenafil by its selective inhibition of phosphodiesterase type 5 is also effective against both types of PAH. It too is now approved in the EU for this purpose in patients in WHO functional class III, but we do not yet have any information about its long-term effects in scleroderma.

Pulmonary endarterectomy

Chronic thromboembolic pulmonary hypertension is a condition that is recognised in an increased percentage of patients. Pulmonary endarterectomy is recognised as being the only curative option for a subgroup of those patients, but anaesthesiologists and intensivists face many challenges in how they manage these patients perioperatively. Ultimately, it is the combination of skills in a multidisciplinary team that leads to a successful procedure and dramatically improves patient's quality of life and life expectancy.

Favorable Effects of Inhaled Treprostinil in Severe Pulmonary Hypertension

OBJECTIVES

This study sought to investigate the effects of inhaled treprostinil on pulmonary hemodynamics and gas exchange in severe pulmonary hypertension.

BACKGROUND

Inhaled iloprost therapy has a proven clinical efficacy in pulmonary arterial hypertension, but this therapy necessitates 6 to 9 inhalation sessions per day. Treprostinil has a longer plasma half-life and might provide favorable properties when applied by inhalation.

METHODS

Three different studies were conducted on a total of 123 patients by means of right heart catheterization: 1) a randomized crossover-design study (44 patients), 2) a dose escalation study (31 patients), and 3) a study of reduction of inhalation time while keeping the dose fixed (48 patients). The primary end point was the change in pulmonary vascular resistance (PVR).

RESULTS

The mean pulmonary arterial pressure of the enrolled patients was approximately 50 mm Hg in all studies. In study 1, both treprostinil and iloprost at an inhaled dose of 7.5 mug displayed a comparable PVR decrease, with a significantly different time course (p < 0.001), treprostinil showing a more sustained effect on PVR (p < 0.0001) and fewer systemic side effects. In study 2, effects of inhalation were observed for 3 h. A near-maximal acute PVR decrease was observed at 30 mug treprostinil. In study 3, treprostinil was inhaled at increasing concentrations with a pulsed ultrasonic nebulizer, mimicking a metered dose inhaler. A dose of 15 mug treprostinil was inhaled with 18, 9, 3, 2 pulses, or 1 pulse, each mode achieving comparable, sustained pulmonary vasodilation without significant side effects.

CONCLUSIONS

Inhaled treprostinil exerts sustained pulmonary vasodilation with excellent tolerability at relatively low doses and may be inhaled in a few breaths.

Bosentan therapy of pulmonary arterial hypertension in connective tissue diseases

BACKGROUND

Pulmonary arterial hypertension (PAH) is a life-threatening and debilitating complication of several connective tissue diseases. We aimed to evaluate the effects of long-term treatment with bosentan, an oral dual endothelin ET(A)/ET(B) receptor antagonist, in a cohort of patients with PAH related to connective tissue diseases.

MATERIALS AND METHODS

In the present prospective, noncontrolled study, 13 patients (nine with systemic sclerosis, two with systemic lupus erythematosus, one with mixed connective tissue disease and one with overlap syndrome including scleroderma and myositis), mostly nonresponders to prostanoids therapy, were treated for 1 year with bosentan. Cardiac haemodynamics and the diagnosis of PAH were performed by Doppler ultrasound examination. Exercise capacity was assessed by 6-min walking test at baseline and at 3, 6 and 12 months of therapy.

RESULTS

During bosentan treatment, progressive improvement of exercise capacity was observed. Walk distance increased in seven patients, remained unchanged in three and slightly decreased in three patients. A progressive significant decrease of right ventricular systolic pressure was also observed, whereas pulmonary artery mean pressure remained unchanged. Adverse effects related to bosentan (elevation of hepatic aminotransferases) were noted in two patients.

CONCLUSION

Long-term treatment with bosentan was effective in improving exercise capacity and pulmonary haemodynamics in patients with PAH related to connective tissue diseases.

[Treatment of systemic sclerosis]

Systemic sclerosis (SSc, scleroderma) is a multisystem disease with a bad prognosis. No drugs have been shown to cure this disease. In view of its pathogenesis, in which immune responses are presumed to play an important role, immune suppressive therapies are widely applied in the treatment of SSc. Recent placebo-controlled trials with cyclophosphamide in patients with SSc complicated by alveolitis, show a modest but significant difference in pulmonary function tests in favour for the cyclophosphamide treated group. Treatment with prostacyclin analogues and endothelin-1 receptor antagonists appear to stabilize pulmonary arterial hypertension, a thus far fatal complication of SSc.