Long-term iloprost infusion therapy for severe pulmonary hypertension in patients with connective tissue diseases

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.

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.

Repurposing of medications for pulmonary arterial hypertension

This manuscript on drug repurposing incorporates the broad experience of members of the Pulmonary Vascular Research Institute's Innovative Drug Development Initiative as an open debate platform for academia, the pharmaceutical industry and regulatory experts surrounding the future design of clinical trials in pulmonary hypertension. Drug repurposing, use of a drug in a disease for which it was not originally developed, in pulmonary arterial hypertension has been a remarkable success story, as highlighted by positive large phase 3 clinical trials using epoprostenol, bosentan, iloprost, and sildenafil. Despite the availability of multiple therapies for pulmonary arterial hypertension, mortality rates have modestly changed. Moreover, pulmonary arterial hypertension patients are highly symptomatic and frequently end up on parental therapy and lung transplant waiting lists. Therefore, an unmet need for new treatments exists and drug repurposing may be an important avenue to address this problem.

The effects of oral treatment for systemic sclerosis related pulmonary arterial hypertension: A systematic review and meta-analysis

OBJECTIVES

The usage of oral therapies, endothelin receptor antagonists (ERAs), phosphodiesterase type-5 (PDE-5) inhibitors and prostaglandin analogs has resulted in improved outcomes in patients with pulmonary arterial hypertension related to systemic sclerosis (SSc-PAH). However, the optimal therapeutics have not been determined.

METHODS

A systematic searching in the databases of Medline (PubMed), Embase, the Cochrane Library (Central) and unpublished clinical trials (clinicaltrials.gov) was conducted to identify the clinical studies with oral treatment for SSc-PAH patients published before 1 June 2019. The data were extracted and the quality was assessed. The main outcomes are exercise capacity and hemodynamic parameters, which were synthesized and analyzed.

RESULTS

In total, 27 clinical trials were enrolled for further analysis. It was demonstrated that bosentan treatment, the widely used drug for PAH, might improve the exercise capacity and pulmonary arterial pressure (PAP) and pulmonary vascular resistance (PVR) in this clinical setting, although without significant difference. Meanwhile, the usage of prostaglandin analogs could improve the parameters mentioned above. Furthermore, combined therapy with ambrisentan and tadalafil significantly increased the treatment efficacy of key parameters in SSc-PAH patients compared with basic treatment.

CONCLUSION

This meta-analysis reveals that combination therapy might provide more benefits to exercise capacity and hemodynamic parameters in SSc-PAH patients. Still more RCTs are needed to provide more solid evidence.

Therapeutic Challenges And Advances In The Management Of Systemic Sclerosis-Related Pulmonary Arterial Hypertension (SSc-PAH)

Systemic sclerosis (SSc) is a rare autoimmune disorder with multi-organ involvement. SSc-associated pulmonary arterial hypertension (SSc-PAH) is one of the leading causes of morbidity and mortality in the SSc population. With advances in our understanding of pulmonary arterial hypertension (PAH) diagnosis and treatment, outcomes for all PAH patients have significantly improved. While SSc-PAH patients have also benefited from these advances, significant challenges remain. Diagnosis of PAH is a challenging endeavor in SSc patients who often have many co-existing pulmonary and cardiac comorbidities. Given the significantly elevated prevalence and lifetime risk of PAH in the SSc population, screening for SSc-PAH is a critically useful strategy. Treatment with pulmonary arterial (PA) vasodilators has resulted in a dramatic improvement in the survival and quality of life of PAH patients. While therapy with PA vasodilators is beneficial in SSc-PAH patients, therapy effects appear to be attenuated when compared to responses in patients with idiopathic PAH (IPAH). This review attempts to chronicle and summarize the advances in our understanding of the optimal screening strategies to identify PAH in patients with SSc. The article also reviews the advances in the therapeutic and risk stratification strategies for SSc-PAH patients.

Antiphospholipid Syndrome and the Lungs

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterised by recurrent thromboembolic events (arterial or venous) and/or morbidity in pregnancy (fetal loss, premature birth, or recurrent embryonic losses) in the presence of laboratory evidence of antiphospholipid antibodies (aPL). APS is a multisystem disorder. Several lung manifestations may develop in patients with APS including pulmonary embolism (PE)/infarction; thromboembolic and non-thromboembolic pulmonary hypertension (PH) (pulmonary arterial hypertension); pulmonary microthrombosis; acute respiratory distress syndrome associated with catastrophic APS; diffuse alveolar haemorrhage; and pulmonary capillaritis. Postpartum syndrome and cryptogenic fibrosing alveolitis (CFA) can be associated with APS. Pulmonary manifestations are relatively rare but are more likely to be life-threatening compared with other complications of APS. Particularly in the presence of aPL, pulmonary manifestations should be suspected in any systemic lupus erythematosus patient with clinical findings such as chest pain, dyspnoea, tachypnoea, and haemoptysis. Early diagnosis and treatment of pulmonary manifestations in APS are essential for improving mortality rates in patients with this condition. The purpose of this review is to assess current evidence around the diagnosis, prognosis, and management of patients with common and rare pulmonary manifestations of APS.

Current status and future prospects for the treatment of antiphospholipid syndrome

Antiphospholipid syndrome (APS) is a prothrombotic disease characterized by thrombosis and pregnancy morbidity in the presence of antiphospholipid antibodies (apL). Management of thrombosis is based on long-term oral anticoagulation and patients with arterial events should be treated aggressively. Primary thrombo-prophylaxis is recommended in patients with systemic lupus erythromatosus (SLE) and obstetric APS. Obstetric APS care is based on high-risk management and treatment with aspirin and heparin. Possible future therapies include statins, hydroxychloroquine, rituximab, and new anticoagulant drugs. Current research is focused on targeting components of the complement system, interfering with aPL-mediated cell activation and using tailored peptides to block the pathogenic subpopulation of aPL.

Life-threatening dermatoses due to connective tissue disorders

Connective tissue disorders such as scleroderma, dermatomyositis and lupus erythematosus are autoimmune, multi-system disorders whose clinical manifestations can be restricted to the skin or may involve many organs. The degree and rate of organ system involvement defer, as does the prognosis and rapidity of disease progression. In this article, scleroderma, dermatomyositis and lupus erythematosus will be reviewed in respect to their life-threatening potential.

Prostacyclin for pulmonary hypertension in adults

BACKGROUND

Primary pulmonary hypertension (PPH) is progressive, resulting in right ventricular failure. Pulmonary hypertension can be idiopathic or associated with other conditions. Prostacyclin is a potent vasodilator and inhibitor of platelet aggregation, and can be given orally, subcutaneously, intravenously or inhaled via a nebuliser.

OBJECTIVES

To determine the efficacy of prostacyclin or one of its analogues in idiopathic primary pulmonary hypertension.

SEARCH STRATEGY

Electronic searches were carried out with pre-specified terms. Searches were current as of July 2004.

SELECTION CRITERIA

Two reviewers selected randomised controlled trials (RCTs) involving adults with pulmonary hypertension for inclusion.

DATA COLLECTION AND ANALYSIS

Study quality was assessed and data extracted independently by two reviewers. Outcomes were analysed as continuous and dichotomous outcomes. We sub-grouped data where possible by aetiology of PH (PPH, PH secondary to connective tissue disorder or mixed populations).

MAIN RESULTS

Nine RCTs of mixed duration (3 days-52 weeks), recruiting 1175 participants were included (NYHA functional classes II-IV). Intravenous prostacyclin versus usual care (four studies): There were significant improvements in exercise capacity of around 90 metres, cardiopulmonary haemodynamics and NYHA functional class over 3 days-12 weeks. Effects were consistent in primary and secondary pulmonary hypertension. Oral prostacyclin versus placebo (two studies): Short-term data (3-6 months) indicated that there was a significant improvement in exercise capacity, but data from one study of 52 weeks reported no significant difference at 12 months. No significant differences were observed for any other outcome. Subcutaneous treprostinil versus placebo (two studies, 8-12 weeks):One large study reported a significant median improvement in exercise capacity of around 16 metres. Cardiopulmonary haemodynamics and symptom scores favoured treprostinil. Infusion site pain and withdrawals due to adverse events were more frequent with treprostinil. Inhaled prostacyclin versus placebo (one study, 12 weeks):There was a significant increase in exercise capacity of approximately 36 metres. Treatment led to better symptom scores and functional class status than with placebo. Subgroup analyses reported by individual studies showed a better exercise capacity in participants with PPH, than those participants with PH secondary to other diseases. Side effects and adverse events were common in the studies.

AUTHORS' CONCLUSIONS

There is evidence that intravenous prostacyclin in addition to conventional therapy at tolerable doses optimised by titration, can confer some short-term benefits (up to 12 weeks of treatment) in exercise capacity, NYHA functional class and cardiopulmonary haemodynamics. There is also some evidence that patients with more severe disease based upon NYHA functional class showed a greater response to treatment.

Prostacyclin for pulmonary hypertension

BACKGROUND

Primary pulmonary hypertension (PPH) is progressive, resulting in right ventricular failure. Survival seldom exceeds five years. Pulmonary hypertension can be idiopathic or associated with other conditions. It is common in patients with diffuse scleroderma and the CREST syndrome where it is clinically, haemodynamically and prognostically indistinguishable from idiopathic primary pulmonary hypertension. Prostacyclin is a potent vasodilator and inhibitor of platelet aggregation. Iloprost is a chemically stable derivative of prostacyclin with similar biologic properties and can be given orally, by infusion or nebulised.

OBJECTIVES

To determine the efficacy of prostacyclin or one of its analogues in idiopathic primary pulmonary hypertension.

SEARCH STRATEGY

A search was carried out using the Cochrane controlled clinical trial register. An update search was conducted on 12th August 2002. Four new trials met the inclusion criteria of the review.

SELECTION CRITERIA

Randomised controlled trials (RCTs) involving patients with primary pulmonary hypertension or pulmonary hypertension secondary to connective tissue disorders were selected by two reviewers.

DATA COLLECTION AND ANALYSIS

Study quality was assessed and data extracted independently by two reviewers. Outcomes were analysed as continuous and dichotomous outcomes, using standard statistical techniques.

MAIN RESULTS

Seven RCTs of short duration (8-12 weeks) were included. Three compared intravenous epoprostenol with conventional therapy. One compared intravenous Iloprost with placebo. One RCT compared oral prostacyclin with placebo, another compared subcutaneous infusion of treprostinil with placebo and a further RCT studied the effects of inhaled iloprost. All the trials showed an improvement in exercise capacity. Cardiopulmonary haemodynamics, dyspnoea scores and symptoms also improved in some of the studies. Side effects and adverse events related to the indwelling catheter (sepsis and thrombosis) were common in intravenous trials. The other routes of administration had less severe side effects.

REVIEWER'S CONCLUSIONS

Intravenous prostacyclin or one of its analogues in addition to conventional therapy over 12 weeks appears to improve exercise capacity, NYHA functional class and several cardiopulmonary haemodynamic variables. There is some evidence that other routes of administration of the drug may also be effective with fewer side effects, which were mainly related to the indwelling catheter.

Long-term administration of beraprost, an oral prostacyclin analogue, improves pulmonary diffusion capacity in patients with systemic sclerosis

The objective of this study was to assess the effect of beraprost sodium, an oral prostacyclin analogue, on pulmonary function in patients with systemic sclerosis. Seventeen patients, with systemic sclerosis and predicted percent values of carbon monoxide diffusion capacity (%DLCO) of less than 95, received beraprost sodium for at least 12 months. Conventional testing for pulmonary function was performed at 12-month intervals and changes were evaluated with special reference to DLCO. Twelve patients completed the treatment. Nine patients showed improvement in DLCO (12.1 +/- 2.3 to 15.5 +/- 4.4 ml/min/mmHg, P < 0.006) and 10 patients showed an increase in %DLCO (66.6 +/- 11.9 to 87.7 +/- 23.2%, P < 0.004). Total lung capacity, vital capacity and forced expiratory volume remained unchanged. This study showed that DLCO levels in patients with systemic sclerosis improved after the administration of beraprost sodium, probably due to the decrease in pulmonary vascular resistance accompanied by increased cardiac output.

The lung in the antiphospholipid syndrome

Patients with antiphospholipid syndrome (APS) may develop a broad spectrum of pulmonary disease. Pulmonary thromboembolism and pulmonary hypertension are the most common complications, but microvascular pulmonary thrombosis, pulmonary capillaritis, and alveolar haemorrhage have also been reported. Clinicians should seriously consider these types of vascular injury when evaluating patients with APS who present with dyspnoea, fever, and infiltrates on chest radiography.

[Pulmonary hypertension associated with connective tissue diseases]

PURPOSE

Pulmonary hypertension is a rare but well-known life-threatening complication of connective tissue diseases. The aim of this article is to analyse the available literature and to report the experience of a pulmonary vascular diseases centre about this complication.

CURRENT KNOWLEDGE AND KEY POINTS

Scleroderma and its limited variant, the CREST syndrome (calcification, Raynaud phenomenon, esophageal dysmotility, sclerodactily, telangiectasia), is the most common connective tissue disease affected by pulmonary hypertension. Dyspnea is the main symptom and is frequently severe. Echocardiography is an excellent exam to detect pulmonary hypertension. However, right heart catheterization is necessary to confirm the diagnosis of pulmonary hypertension and to test vasoreactivity with a potent vasodilator such as nitric oxide. Pulmonary hypertension is less severe in patients with connective tissue diseases perhaps because of an earlier diagnosis. A significantly lower proportion of patients presents an acute vasodilator response, suggesting an early constitution of irreversible pulmonary vascular lesions. Continuous intravenous epoprostenol therapy seems to be less effective as compared with patients with primitive pulmonary hypertension and does not improve survival. So, we observed dramatic improvement in rare cases after immunosuppressive therapy.

FUTURE PROSPECTS AND PROJECTS

New treatments with oral, subcutaneous or inhaled stable prostacyclin analogs or with an endothelin receptor antagonist are currently being evaluated. The role of immunosuppressive therapy has to be defined.

Treating systemic sclerosis in 2001

Systemic sclerosis (SS) is characterized by sclerosis of the dermis and internal organs and by vascular abnormalities. Although the pathophysiology of the disease has been partly elucidated, the efficacy of long-term treatments remains limited, with no significant increase in survival in prospective studies. Conventional drug treatments are disappointing in clinical practice, and in a recent prospective randomized study standard-dose D-penicillamine was not more effective than mini-dose D-penicillamine. New long-term treatments are emerging for diffuse SS, including cyclophosphamide for patients with progressive interstitial lung disease or stem cell transplantation for those with early organ involvement. The most effective treatments remain symptomatic, such as angiotensin-converting enzyme inhibitors for acute renal crisis, calcium channel antagonists for Raynaud's phenomenon, and proton pump inhibitors for the complications of gastroesophageal reflux. This review article focuses on long-term treatments that are most likely to be effective and suggests symptomatic treatment strategies tailored to specific organ involvements.

Drug treatment of scleroderma

Scleroderma or systemic sclerosis is a rare condition with many clinical manifestations including Raynaud's phenomenon. As with many other rarely encountered diseases, drug therapy for scleroderma is often empirical with little evidence in the form of randomised controlled trials to aid drug choice. Raynaud's phenomenon has been recognised for well over 100 years. A considerable number of clinical trials in this area have demonstrated unequivocally the use of nifedipine as a gold standard. Large studies have also demonstrated the efficacy of iloprost. However, this drug is not as yet licensed for scleroderma in the UK or elsewhere. This presents an additional problem as information regarding the use and administration of unlicensed drugs is often sparse and post-marketing surveillance to assess safety is not routinely performed. When looking at the other distinct conditions encountered by a patient with scleroderma it becomes evident that trials are often retrospective or limited in patient numbers. Studies investigating the use of methotrexate, antithymocyte globulin and cyclophosphamide in patients with scleroderma have been very small and in some cases not well designed. The major work on penicillamine was a retrospective trial. Again these drugs are not licensed for use in scleroderma. Drug therapy for pulmonary hypertension secondary to scleroderma closely follows that outlined for primary pulmonary hypertension. In the US there is a patient registry for primary pulmonary hypertension that has enabled well designed, large-scale studies to demonstrate the benefits of epoprostenol in severe primary pulmonary hypertension. Hence, research in this area has progressed considerably over the last decade. Clearly, a considerable amount of work is being carried out to elucidate new treatment regimens for scleroderma, however, evaluation of these studies is proving to be a difficult process. Designated hospital centres for scleroderma (there are currently 2 in the UK), better markers of disease activity and methods to measure improvement or deterioration in affected organs, should enable research into aetiology, disease progression and treatment to be carried out on a larger scale resulting, hopefully, in more conclusive answers.

Hemodynamic effects of Bosentan, an endothelin receptor antagonist, in patients with pulmonary hypertension

BACKGROUND

Few treatments are available for isolated pulmonary hypertension (PHT), which has a high morbidity and mortality. This trial was designed to assess the hemodynamic effects of bosentan, an endothelin receptor antagonist, in patients with PHT, in which local overproduction of endothelin-1 (ET-1) is thought to play a pathogenic role.

METHODS AND RESULTS

An open-label, dose-ranging study was performed in 7 female patients with primary PHT (n=5) or isolated PHT associated with limited scleroderma (n=2). Infusions of 50, 150, and 300 mg were administered at 2-hour intervals, and the hemodynamic responses were measured. Bosentan caused a dose-dependent fall in total pulmonary resistance (-20.0+/-11.0%, P=0.01) and mean pulmonary artery pressure (-10.6+/-11.0%, P>0.05). However, there was also a fall in the systemic vascular resistance (-26.2+/-12.8%, P<0.005) and mean arterial pressure (-19.8+/-14.4%, P<0.001). There was a slight increase in cardiac index (15+/-12%, P>0.05) and a dose-dependent rise in ET-1 but no significant change in other hemodynamic variables, gas exchange, or other vasoactive mediators.

CONCLUSIONS

Intravenous bosentan is a potent but nonselective pulmonary vasodilator at the doses tested, even in patients resistant to inhaled nitric oxide. Transient increases in plasma ET-1 were observed, consistent with a blockade of endothelial ET(B) receptors. Systemic hypotension and other significant events during the study indicate that its intravenous use in patients with severe PHT may be limited. Implications for future trial design and studies of chronic oral treatment are discussed.

Scleroderma and related disorders: therapeutic aspects

Improvements in management of systemic sclerosis have occurred through a growing understanding of pathogenic events accompanied by advances in diagnosis and assessment, as well as developments in organ-based therapeutics. Unfortunately, disease-modifying therapies of proven efficacy remain elusive and several agents in current use have been shown in well-controlled clinical trials to be of questionable benefit. More positively, there have been advances in the treatment of major visceral complications such as renal crisis, pulmonary fibrosis, pulmonary hypertension, gastrointestinal involvement and in the management of scleroderma-associated Raynaud's phenomenon. Current approaches are reviewed, evidence supporting or refuting the use of putative disease-modifying agents is discussed, and new strategies are described that are currently being considered for this fascinating but complex multisystem connective tissue disease.

Systemic sclerosis-associated pulmonary hypertension: short- and long-term effects of epoprostenol (prostacyclin)

OBJECTIVE

To evaluate the short- and long-term effects of intravenous epoprostenol in patients with pulmonary hypertension (PH) associated with systemic sclerosis (SSc).

METHODS

Sixteen patients with SSc-associated PH and New York Heart Association (NYHA) class III or IV symptomatology underwent right heart catheterization for determination of baseline hemodynamic values. Vasoreactivity was assessed with either inhaled nitric oxide or intravenous adenosine. After a medication washout period, all patients received intravenous epoprostenol in incrementally increasing doses; tolerance was assessed according to symptoms and hemodynamic findings at each dose increment and at the conclusion of the medication trial. Once a stable medication regimen was established, patients were discharged and followed up as outpatients for assessment of symptoms and exercise tolerance as measured by change in the NYHA class. Repeat hemodynamic testing was performed in 4 patients at 1 year and in 2 patients at 2 years of treatment.

RESULTS

Therapeutic response to epoprostenol, defined by a reduction in the pulmonary vascular resistance of > or =25%, was achieved in the short-term treatment period in 13 of 16 patients (81.3%). Improvement in symptoms and exercise tolerance occurred in all patients, and a significant short-term hemodynamic response was observed. Followup hemodynamic tests revealed persistent favorable responses in all 4 of the patients studied.

CONCLUSION

Most patients with PH secondary to SSc manifest favorable hemodynamic responses to epoprostenol in the short term. Long-term epoprostenol was generally well tolerated and provides a potential therapeutic option for patients with PH secondary to SSc.

[Pulmonary involvement in systemic scleroderma. Part II. Isolated pulmonary arterial hypertension, bronchopulmonary cancer, alveolar hemorrhage]

INTRODUCTION

Pulmonary interstitial fibrosis is the most frequent cause of lung disease in systemic sclerosis. However, other pulmonary complications exist, including lung cancer, alveolar hemorrhage, and in particular isolated pulmonary arterial hypertension, which is still considered the bête noire as regards this disease.

CURRENT KNOWLEDGE AND KEY POINTS

The prevalence of pulmonary arterial hypertension has been reported to range from 5 to 60% in cases of systemic sclerosis; isolated pulmonary arterial hypertension has been principally observed in subjects with a ten-year history of limited forms of the disease. As the patient remains asymptomatic for a long period, with nonspecific respiratory clinical manifestations, the diagnosis is made at a much later stage in the course of the disease. The diagnostic method of choice is echocardiography-doppler, which should be performed during the preliminary investigation, and at follow-up. The prognosis is poor, and patient survival rate at 2 years after onset of symptoms amounts to 40%. To date, no curative therapy for pulmonary arterial hypertension has yet been found.

FUTURE PROSPECTS AND PROJECTS

A knowledge of the mechanisms involved in the development of isolated pulmonary arterial hypertension is essential to the determination of new and relevant therapeutic strategies. Vasodilatory treatment, notably calcium channel blockers, prostacyclin and analogs such as iloprost, may be effective at an early stage of the disease before the appearance of permanent vascular damage.

Cyclosporin A and iloprost treatment of systemic sclerosis: clinical results and interleukin-6 serum changes after 12 months of therapy

OBJECTIVES

The main aim was to analyse the long-term therapeutic effects on systemic sclerosis (SSc) patients of treatment with either (i) iloprost alone or (ii) low-dose oral cyclosporin A (CyA) associated with iloprost. A secondary aim was to analyse interleukin-6 (IL-6) serum levels in SSc patients before and after 1 yr of treatment.

METHODS

A clinical trial was performed in which 20 consecutive SSc patients were alternately randomized into two homogeneous groups receiving either monthly i.v. iloprost (1 ng/kg/min in 6 h i.v. infusion, for 5 consecutive days, 1 week per month) (Group I) or low-dose CyA (2.5 mg/kg/day) associated with iloprost administration (Group II). IL-6 concentrations were evaluated by ELISA in the sera of each patient before and after 1 yr of therapy and in 20 healthy subjects.

RESULTS

After 1 yr of therapy, a significant improvement of skin (P=0.008), microvascular (P=0.004) and oesophageal (P=0.05) morphological and functional parameters was observed only in Group II patients. Furthermore, after 1 yr of treatment, a significant reduction (P=0.007) of IL-6 serum concentration was observed only in Group II patients.

CONCLUSIONS

Collectively, our data suggest that the combination of low-dose CyA with iloprost administration may be of clinical utility in SSc and that a mechanism of action of CyA in SSc may include the decrease in IL-6 production.

Novel therapeutic strategies in scleroderma

Optimal management for scleroderma (systemic sclerosis) is likely to require treatment of the underlying disease process, which remains incompletely understood, and also of the organ-based complications of this heterogeneous condition. Clinical trials evaluating several potential agents have been completed recently, including D-penicillamine and interferon alpha. Unfortunately none of these studies has suggested significant efficacy. This article focuses on new treatment approaches using existing therapeutic agents, such as prostacyclin, and considers the potential usefulness of new agents (eg, relaxin, halofuginone) or strategies such as intensive immunosuppression with peripheral stem cell rescue. Ultimately, a better understanding of disease pathogenesis may facilitate the development of targeted therapy against key events or mediators, but for the present better evaluation of existing agents and a focus on optimizing protocols for organ-based complications, such as pulmonary vascular disease or hypertensive renal crisis, are important goals.

Pulmonary hypertension secondary to systemic lupus erythematosus: prolonged survival following treatment with intermittent low dose iloprost

Pulmonary hypertension (PHT) associated with systemic lupus erythematosus (SLE) has a dismal prognosis. Vasodilators and immunosuppressive therapy have been tried over the years with discouraging results. Prostacyclin (PGI2) which has potent vasodilatatory and anti-platelet effects has been demonstrated to significantly decrease pulmonary arterial pressure and pulmonary vascular resistance during acute infusion. Satisfactory response has been reported in SLE patients with PHT treated with short-term intravenous continuous PGI2 infusion. We report here a 48-month experience of the use of monthly low dose infusion of a PGI2 analogue, iloprost, in a SLE patient with pulmonary hypertension in New York Heart Association functional Class III. There was an initial haemodynamic response to an acute infusion of iloprost. Repeated infusions were followed by marked improvement in her functional status and her mean pulmonary arterial pressure dropped from 80 mmHg in the first few months and remained static at around 55 mmHg for the subsequent years.

Pulmonary hypertension in collagen vascular disease

Pulmonary hypertension associated with collagen vascular disease often eludes diagnosis, sometimes causing considerable morbidity or even death before being identified. This review details its characteristic clinical features, appropriate diagnostic and treatment approaches, and expected outcomes.

[Antiphospholipid antibody syndrome]

BACKGROUND

Antiphospholipid antibodies comprise a family of auto-antibodies mainly characterized by the presence of the lupus anticoagulant (LA) and anticardiolipin antibodies (ACA).

CLINICAL APPEARANCE

The antiphospholipid antibody syndrome is defined by the appearance of frequent thromboses, repeated fetal losses and thrombocytopenia. Other clinical manifestations associated with APA include migraine, chorea, hemolytic anemia, heart valve disease, Budd-Chiari syndrome, perpetual pancreatitic episodes, intestinal infarctions, malignant hypertension, livedo reticularis, pre-eclampsia, fetal growth retardation or catastrophic antiphospholipid syndrome. LA and ACA occur in a variety of clinical conditions (secondary antiphospholipid antibody syndrome, SAPS), including other autoimmune disorders, infectious diseases, neoplastic disorders, in association with the use of certain drugs or in otherwise healthy individuals (primary antiphospholipid antibody syndrome, PAPS).

TREATMENT

Patients with thrombosis associated with APA should receive long-term anticoagulation therapy, whereas treatment of asymptomatic patients seems to be not indicated, because only approximately 10% of patients with APA may develop thrombotic complications. In patients with PAPS there is no evidence that the prophylactic administration of immunosuppressive drugs will prevent thromboembolic events.

Acute effects of nebulised epoprostenol in pulmonary hypertension due to systemic sclerosis

Pulmonary hypertension often has a lethal outcome in systemic sclerosis and the treatment is challenging. Epoprostenol is a potent pulmonary vasodilator and its efficacy has been demonstrated when delivered by the intravenous and aerosolized routes. We report the haemodynamic and functional benefits of epoprostenol administered by inhalation to a spontaneously breathing patient with partially reversible pulmonary hypertension due to systemic sclerosis. Aerosolized epoprostenol, equivalent to the maximum tolerated intravenous dose (31.2 micrograms), produced a 58% fall in pulmonary vascular resistance, increased the cardiac output by 42% and improved functional performance by one MET (3.5 ml kg-1 min-1 of oxygen uptake) without any significant side-effects. Selective distribution of epoprostenol by the inhaled route may offer a new strategy for treatment of pulmonary hypertension.

Recognition and management of pulmonary hypertension

Pulmonary hypertension (mean pulmonary arterial pressure > 20mm Hg at rest or > 30mm Hg during exercise) occurs (i) as primary pulmonary hypertension (no known underlying cause), (ii) as persistent pulmonary hypertension of the newborn or (iii) secondary to a variety of lung and cardiovascular diseases. In the last 10 to 15 years there have been significant advances in the medical management of this debilitating and life-threatening disorder. The main drugs in current use are anticoagulants (warfarin, heparin) and vasodilators, especially oral calcium antagonists, intravenous prostacyclin (prostaglandin I2; epoprostenol) and inhaled nitric oxide. Calcium antagonists, (e.g. nifedipine, diltiazem) are used chiefly in primary pulmonary hypertension. They are effective in patients who give a pulmonary vasodilator response to an acute challenge with a short acting vasodilator (e.g. prostacyclin, nitric oxide or adenosine), and are used in doses greater than are usual in the treatment of other cardiovascular disorders. Prostacyclin, given by continuous intravenous infusion, is effective in patients even if they do not respond to an acute vasodilator challenge. The long term benefit in these patients is thought to reflect the antiproliferative effects of the drug and/or its ability to inhibit platelet aggregation. It is used either as long term therapy or as a bridge to transplantation. Inhaled nitric oxide, which is used mainly in persistent pulmonary hypertension of the newborn, has the particular benefit of being pulmonary selective, due to its route of administration and rapid inactivation. Anticoagulants have a specific role in the treatment of pulmonary thromboembolic pulmonary hypertension and are also used routinely in patients with primary pulmonary hypertension. Nondrug treatments for pulmonary hypertension include (i) supplemental oxygen (> or = 15 h/day), which is the primary therapy in patients with pulmonary hypertension secondary to chronic obstructive pulmonary disease and (ii) heart-lung or lung transplantation, which nowadays is regarded as a last resort. Different types of pulmonary hypertension require different treatment strategies. Future advances in the treatment of pulmonary hypertension may come from the use of drug combinations, the development of new drugs, such as endothelin antagonists, nitric oxide donors and potassium channel openers, or the application of gene therapy.

Manifestations of scleroderma pulmonary disease

Scleroderma is a multisystem disease of unknown cause characterized by synthesis and deposition of excessive extracellular matrix and vascular anti-GBM antibodies, leading to pulmonary hemorrhage and glomerulonephritis with rapidly progressive renal insufficiency. Recent advances in the understanding of disease pathogenesis and diagnosis and treatment have significantly improved our ability to recognize the syndrome, distinguish it from other similar disorders, and offer successful treatment. This article focuses on the pathogenetic features, clinical manifestations, diagnostic strategies, and therapeutic principles of anti-GBM disease.

Long-term intravenous prostaglandin (epoprostenol or iloprost) for treatment of severe pulmonary hypertension

OBJECTIVE

To investigate the relation between the severity of pulmonary hypertension and the outcome of medical treatment.

METHODS

98 patients with primary pulmonary hypertension--nine (6%) with systemic disease and pulmonary hypertension and 39 (27%) with thromboembolic pulmonary hypertension--received medical treatment and were followed between 1982 and 1995. They were given long term intravenous prostaglandin treatment (either epoprostenol (n = 61) or iloprost (n = 13)) or conventional treatment with oral anticoagulants (n = 24) with or without calcium channel blockers. Event-free survival was measured to death or transplant surgery, or pulmonary thromboendarterectomy.

RESULTS

Prognosis (hazard ratio) was affected by: New York Heart Association grade, 1.52 (95% confidence interval 1.11 to 2.09); mixed venous oxygen saturation (SvO2%), 0.97 (0.95 to 0.98); cardiac index, 0.72 (0.49 to 1.06); mean right atrial pressure, 1.04 (1.01 to 1.07); and pulmonary vascular resistance, 1.02 (1.00 to 1.04). The median event-free survival time of patients with SvO2 < 60% was 239 days (0 to 502) on conventional treatment (n = 22) and 585 days (300 to 870) on prostaglandin treatment (n = 42). No difference was seen in patients with SvO2 > or = 60% between conventional treatment and prostaglandin treatment, survival being 1275 days (732 to 1818; (n = 48)) and 986 days (541 to 1431; n = 30)), respectively. Capacity for pulmonary vasodilatation did not predict outcome of treatment.

CONCLUSIONS

Continuous intravenous prostaglandins were more effective than anticoagulants, with or without calcium channel blockers, in prolonging survival in patients with right heart failure. In these patients a capacity to vasodilate did not predict outcome from medical treatment.

Management of systemic sclerosis: the art and science

There have been substantial strides in the therapy of systemic sclerosis (SSc) in recent years, particularly in the management of individual organ manifestations. Effective treatments are available for SSc renal crisis and many of the gastrointestinal manifestations of the disease. Raynaud's phenomenon, a nearly universal problem in SSc, also may be effectively managed. Treatment of the pulmonary complications, pulmonary hypertension and interstitial lung disease, remains difficult. Patients with early, diffuse SSc are the best candidates for experimental therapies intended to modify the overall disease process. Most disease-modifying agents have been directed at the fibrotic and inflammatory processes characteristic of SSc and have achieved little success. Future therapies may target mediators of vascular dysfunction in SSc. The success of future therapeutic trials will depend on collaborative efforts between treatment centers.

The acute effects of prostacyclin on pulmonary hemodynamics in patients with pulmonary hypertension secondary to systemic sclerosis

OBJECTIVE

To determine whether patients with isolated pulmonary hypertension secondary to systemic sclerosis (SSc) have a pulmonary vasculature that is responsive to treatment with vasodilators.

METHODS

Seven SSc patients with pulmonary hypertension underwent right heart catheterization. Pulmonary pressures and cardiac output were measured before and during a systemic intravenous infusion of prostacyclin.

RESULTS

Both pulmonary arterial mean pressure and pulmonary vascular resistance decreased significantly with prostacyclin infusion (median decrease 11% and 32%, respectively), with a concomitant increase in cardiac output (median increase 26%). No adverse hemodynamic effects were noted during the infusion.

CONCLUSION

Vasospasm contributes to the pulmonary hypertension complicating SSc. This feature may be amenable to treatment with vasodilators.

Treatment of pulmonary hypertension with the continuous infusion of a prostacyclin analogue, iloprost

OBJECTIVE

To compare prostacyclin with an analogue, iloprost, in treatment of severe pulmonary hypertension.

PATIENTS

Eight patients with severe pulmonary hypertension: primary in five, thromboembolic pulmonary hypertension in three.

METHODS

All patients underwent right heart catheterisation. Mean (SEM) right atrial pressure was 9.9 (2.2) mm Hg, mean pulmonary artery pressure 67.4 (3.0) mm Hg, cardiac index 1.75 (0.13) l/min/m2 and mixed venous oxygen saturation 59.1(3.1)%. Continuous intravenous epoprostenol (prostacyclin, PGI2) or iloprost was given for phase I (three to six weeks); the patients were then crossed over to receive the alternate drug in an equivalent phase II.

MAIN OUTCOME MEASURES

Exercise tolerance was measured at baseline and at the end of phase I and II with a 12 minute walk; distance covered, rest period, percentage drop in arterial oxygen saturation (delta Sao2%) and percentage rise in heart rate (delta HR%).

RESULTS

Walking distance covered rose from (mean (SEM)) 407.5 (73) to 591 (46) m with PGI2 (p = 0.004) and to 602.5 (60) m while on iloprost (p = 0.008). Rest period decreased from 192 (73) seconds at baseline to 16 (16) seconds with PGI2 (p = 0.01) and to 58 (34) seconds with iloprost (p = 0.008). Delta HR% was 37.5(6)% at baseline, 35(3)% on PGI2, and 24(6)% on iloprost (p = 0.04).

CONCLUSIONS

Both intravenous PGI2 and iloprost caused significant improvement in exercise tolerance. Iloprost offers an alternative to PGI2 treatment of severe pulmonary hypertension.

Pulmonary hypertension in systemic autoimmune disease

Rare in occurrence, insidious in onset, and relentless in its course, pulmonary hypertension in systemic autoimmune disease remains one of the most challenging entities to diagnose and treat today. The subtlety and nonspecificity of its symptoms and signs, the lack of availability of sensitive, noninvasive, accurate diagnostic tests, the rudimentary understanding we have of its pathogenesis, the multiplicity of findings on histopathologic survey, and the paucity of data from large-scale therapeutic trials in this population all pose many frustrations for patient and physician. Although supportive, symptomatic therapy remains the mainstay of treatment, we continue to await the results of carefully conducted clinical trials investigating antiinflammatory drugs and vasodilators. Careful scrutiny of the histologic lesions seen in pulmonary hypertension has shown striking similarity with the changes of PPH in some patients, and close follow-up of patients diagnosed with PPH has shown that some of them later develop evidence of a specific autoimmune disease like scleroderma. A natural tendency to extrapolate the use of therapeutic modalities of PPH to patients with autoimmune disease-associated pulmonary hypertension then results. We are thus encouraged by the lessons learned from the past about PPH; studies of patients with PPH have identified a subset of them who enjoy a distinct survival advantage with use of vasodilators or transplantation. We remain hopeful that future investigations in the treatment of autoimmune disease-associated pulmonary hypertension will yield similar information, and that we will be able to provide afflicted individuals some long-awaited improvements in quality and duration of life.

Clinical trials in pulmonary hypertension

Progress in treatment of pulmonary hypertension has been impaired by the lack of formal clinical trials. This is now beginning to change, and the impact on our approach to treating patients with pulmonary hypertension in substantial. As with other relatively uncommon medical disorders, randomized, controlled, multi-center trials are needed to assess the safety and efficacy of potential therapeutic modalities. Treatments showing promise at the level of small pilot studies within a single center should be studied more rigorously.

[Primary pulmonary hypertension: a rare but often fatal complication of Crest syndrome]

In a retrospective study of 194 systemic sclerosis, we selected 37 Crest syndrome patients. Among these 37 patients, five presented a primary pulmonary hypertension. For three of these patients, the evolution of this primary pulmonary hypertension was rapidly fatal, one died of another cause. One died without certitude that death is imputable to HTAP. Diagnosis and management of the evolution of primary pulmonary hypertension may be easily assessed by doppler-echocardiography.

Scleroderma. Clinical problems. The lungs

A recent follow-up study found that patients with pulmonary involvement (with no renal or cardiac involvement) survived a median of 78 +/- 17 months. Another study found death from SSc was most frequently due to pulmonary hypertension. Improved diagnostic modalities and better understanding of the pathophysiology of SSc lung disease are essential, because mortality from this SSc lung disease remains high. During the past decade, advances have been made in the understanding of the alveolitis of SSc lung disease. Although the inciting injury remains uncertain, a cascade of inflammatory and fibrosing mediators culminates in a chronic state of interstitial lung disease. There is increasing evidence that the fibrogenic cytokines PDGF and TGF-beta are major contributors to the pathophysiology of interstitial lung disease, including that of SSc. Future research aimed at modifying the biologic response to such cytokines may yield novel therapeutic approaches to the management of this type of lung disease. Similarly, improved understanding of mediators of vascular tone, such as endothelin and nitric oxide, may yield much-needed treatments for pulmonary hypertension.

Treatment of systemic sclerosis

Guidelines for the conduct of clinical trials in progressive systemic sclerosis have been recommended to determine drug efficacy better. To date, the results of disease-modifying drugs in scleroderma have been disappointing. The treatment of esophagitis has been revolutionized by omeprazole. Raynaud's phenomenon can be treated with calcium channel blockers and iloprost. Scleroderma renal crisis can be treated with aggressive blood pressure control using angiotensin converting enzyme inhibitors. The best treatment for rapidly progressive scleroderma lung is still unknown. Future treatments in scleroderma should be tested with the use of recommended guidelines.

Acute hemodynamic responses to inhaled nitric oxide in patients with limited scleroderma and isolated pulmonary hypertension

BACKGROUND

Inhaled nitric oxide (NO) is a selective pulmonary vasodilator that reduces pulmonary vascular resistance (PVR) in patients with primary pulmonary hypertension. Their responses to inhaled NO predict their responses to other vasodilators, such as prostacyclin, and provide an estimate of the "fixed" component of their increased PVR. Some patients with limited cutaneous systemic sclerosis develop isolated pulmonary hypertension with a similar clinical course. Therefore, we have measured the acute hemodynamic response to inhaled NO in such patients.

METHODS AND RESULTS

Seven patients were studied during inhalation of increasing concentrations of NO (0 to 80 ppm). Complete hemodynamic data were collected on five patients. They demonstrated a selective, dose-dependent, and rapidly reversible fall in PVR (34%) and mean pulmonary artery pressure (17%). There was a nonsignificant increase in cardiac index but no change in mean arterial pressure or systemic vascular resistance. The mean right atrial pressure fell (27%), but there was no change in pulmonary artery occlusion pressure. Of the seven patients, five responded to inhaled NO ( < or = 40 ppm) with a decrease in total pulmonary resistance of at least 20%.

CONCLUSIONS

Inhaled NO is an effective and selective pulmonary vasodilator in a significant number of patients with pulmonary hypertension associated with limited cutaneous systemic sclerosis. It may be useful in determining the potentially reversible contribution to the increased PVR and should be considered for patients with acute pulmonary vascular crisis.

a 49-year-old woman with dyspnoea, palpitations and syncope

Pulmonary hypertension is rarely described in association with Sjögren's syndrome. The authors report the case of a patient in which pulmonary hypertension was the inaugural clinical manifestation of primary Sjögren's syndrome. Clinical assessment, differential diagnosis, etiopathological implications, and therapeutic approach are discussed.