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

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.

WHO Group 1 pulmonary arterial hypertension: current and investigative therapies

Major advances have been made in the treatment of World Health Organization Group 1 pulmonary arterial hypertension (PAH). Since the mid-1990s, nine medications have become available in the United States to target three key pathophysiologic derangements in PAH - the prostacyclin, endothelin, and nitric oxide pathways. As a group, these agents have led to improvements in functional capacity, symptoms, hemodynamics, and survival. Most patients with mild to moderate PAH are started on orally active agents such as endothelin receptor antagonists or phosphodiesterase inhibitors. Patients with more severe disease, particularly those with evidence of right heart failure, should be treated with continuous prostacyclin infusion or a combination of a prostacyclin and oral therapy. Each medication has unique properties and clinical considerations, and the selection of an appropriate therapy must be tailored to the individual patient. None of the currently available WHO Group 1 PAH therapies are curative, however, and it is the hope that new therapies in development may halt or reverse disease progression. This review will discuss the major therapeutic classes of presently available medications and their role in managing the patient with PAH. We will also review data supporting the use of combination therapy, adjuvant background therapy, and new agents currently under investigation.

Diagnosis and management of pulmonary arterial hypertension

Pulmonary arterial hypertension is a rare disease, which requires a high index of suspicion to diagnose when patients initially present. Initial symptoms can be nonspecific and include complaints such as fatigue and mild dyspnea. Once the disease is suspected, echocardiography is used to estimate the pulmonary arterial (PA) pressure and to exclude secondary causes of elevated PA pressures such as left heart disease. Right heart catheterization with vasodilator challenge is critical to the proper assessment of pulmonary hemodynamics and to determine whether patients are likely to benefit from vasodilator therapy. Pathologically, the disease is characterized by deleterious remodeling of the distal pulmonary arterial and arteriolar circulation, which results in increased pulmonary vascular resistance. In the last fifteen years, medications from three different classes have been approved for the treatment of pulmonary arterial hypertension. These include the prostanoids, endothelin receptor antagonists, and phosphodiesterase-5 inhibitors.

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.

Les traitements de l’hypertension artérielle pulmonaire à l’heure de la T2A. Recommandations du groupe de travail “Maladies vasculaires pulmonaires” de la Société de pneumologie de langue française

Activity-based financing (that is, casemix-based hospital payments, known as T2A) is intended to harmonize and improve the fairness of remuneration of public and private hospitals. T2A will ultimately rely mainly on a flat rate per admission, set according to the diagnosis-related group (DRG). Although payment for drugs is usually included in the DRG price, some expensive drugs will be reimbursed on an additional cost basis after implementation of a "best practices" agreement. Four drugs used for treatment of pulmonary arterial hypertension are eligible for this additional reimbursement: 3 prostacyclin derivatives (intravenous epoprostenol, inhaled iloprost, and subcutaneous treprostinil), and oral bosentan, an endothelin receptor antagonist. The Pulmonary Vascular Diseases working group of the French Society of Pulmonary Medicine has developed guidelines for the best practices in use of these drugs.

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.

[The methods for screening pulmonary hypertension related to systemic sclerosis in France. Descriptive survey of the French Research Group on Sclerosis]

CONTEXT AND OBJECTIVES

Pulmonary hypertension (PHT) represents one of the severest complications and is life-threatening for patients suffering from systemic sclerosis (SSc). In France, the modalities for screening and treating PHT related to SSc are not well codified and no consensus has been reached. We conducted a survey among physicians inscribed on the list of the French Research Group on Sclerosis (GRFS - Groupe de Recherche Francais sur la Sclerodermie) to gather information on the status of the management of PHT related to SSc.

METHODS

In 2002, we sent a questionnaire to 160 physicians, members of the GRFS, to assess the epidemiology and clinical profile of SSc patients as well as the modalities of screening and management of PHT in these patients.

RESULTS

Eighty-eight physicians in 71 centres replied to the questionnaire. Each centre followed-up a mean of 33 SSc patients, with a global distribution of 53% limited and 47% diffused SSc. These physicians saw a mean of 5 new cases of SSc per year. The patients had been referred by town practitioners (53%) or from the hospital (47%). The mean number of SSc patients with PHT was of 5.1 per physician (1.5 new SSc + PHT patients per year). Almost all the centres (65/67) who replied systematically screened for PHT in SSc patients using Doppler echocardiography a mean of every 1.3 years. For the management of the patients exhibiting PHT, the majority (41/63) of centres collaborated with a specialized unit. Around one third of the centres treated these patients with calcium channel inhibitors (82%) and/or prostacyclin (90%). All the patients were followed-up by Doppler echocardiography. The majority of the physicians (72%) were interested in a research protocol on the subject and each could have included 4 patients, i.e., a total of 160.

CONCLUSION

Pulmonary hypertension, a severe complication of SSc is screened for by the physicians of the GRFS using echocardiography with a frequency similar to Who guidelines (1.3 versus once/year).

Hemodynamics and survival in patients with pulmonary arterial hypertension related to systemic sclerosis

STUDY OBJECTIVES

The goal of this study was to determine whether the survival of patients with pulmonary hypertension related to systemic sclerosis (SScPH) was different from that of patients with other forms of pulmonary arterial hypertension.

DESIGN

Retrospective cohort study.

SETTING

Tertiary care medical center.

PATIENTS

Our cohort was composed of 33 patients with pulmonary hypertension that is sporadic, familial, or related to anorexigen use (PPH) and 22 patients with SScPH who underwent initial pulmonary artery catheterization and vasodilator study at our center between January 1997 and June 2001.

MEASUREMENTS AND RESULTS

Patients with SScPH had somewhat lower percentage of predicted lung volumes than patients with PPH (total lung capacity, 80% vs 92%; p = 0.06) and had lower percentage of predicted diffusion capacity of the lung for carbon monoxide (42% vs 68%; p = 0.0002). Right atrial pressure, pulmonary artery pressure, and cardiac index were similar between the groups. Patients with SScPH and PPH were treated with usual medical therapies, such as digoxin, warfarin, and continuous IV epoprostenol. Despite these similarities, the risk of death in patients with SScPH was higher than in patients with PPH (unadjusted hazard ratio, 2.9; 95% confidence interval, 1.1 to 7.8; p = 0.03). This increased risk appeared to persist after adjustment for a variety of demographic, hemodynamic, or treatment variables.

CONCLUSIONS

Despite having similar hemodynamics, patients with SScPH have a higher risk of death than patients with PPH. Future studies of the mechanism and therapy of pulmonary arterial hypertension should focus on the distinctions between the different forms of this disease.

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.

Pulmonary hypertension associated with connective tissue disease

Pulmonary arterial hypertension is a life threatening complication of several connective tissue diseases including scleroderma (both diffuse and limited scleroderma, or the CREST syndrome--calcinosis cutis, Raynaud's phenomenon, esophageal dysfunction, sclerodactyly, and telangectasia), systemic lupus erythomatosis (SLE), mixed connective tissue disease (MCTD), and less commonly, rheumatoid arthritis (RA) and dermatomyositis/polymyositis. This report reviews the occurrence of this complication, potential etiologies, clinical presentation, and treatment options.

Life-threatening complications of systemic sclerosis

Pulmonary arterial hypertension is common in patients with SSc. Fig. 1 shows the diagnostic and therapeutic approach to PAH in SSc. Doppler echocardiography may suggest the diagnosis, but RHC is necessary to confirm PAH and to measure vasoreactivity. Therapy is directed at the underlying connective tissue disease. Vasoreactive patients often benefit from therapy with high-dose calcium-channel [figure: see text] blockers, but most patients are not vasoreactive. Intravenous epoprostenol and oral endothelin-1 receptor antagonists improve hemodynamic measurements and symptoms in SSc-associated PAH. The therapy of right ventricular failure is focused on vasodilators, inotropes, and diuretics with careful attention to avoiding systemic hypotension. The scleroderma pulmonary-renal syndrome and the scleroderma renal crisis are distinct syndromes with different clinical presentations, histopathologic manifestations, treatments, and outcomes. The scleroderma pulmonary renal syndrome is an autoimmune vasculitis of kidney and lung associated with normal blood pressure. Treatment is supportive, and prognosis is dismal. In contrast, scleroderma renal crisis is associated with systemic hypertension, onion skinning of afferent arterioles, and response to ACE inhibition and renal replacement therapy. Pericardial effusions are common but only occasionally lead to tamponade. Esophageal dysmotility is often associated with aspiration, leading to pulmonary fibrosis, pneumonia, or ARDS. Diffuse bowel involvement may result in pseudo-obstruction, bacterial overgrowth, or malabsorption. Prokinetic agents, antibiotics, and parenteral nutrition may be required.

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.

Current treatment options in systemic Sclerosis (Scleroderma)

Systemic Sclerosis (SSc) or Scleroderma is a generalized autoimmune disease with variable involvement of the skin and major organs. Etiology and pathogenesis are still largely unknown, but a variety of humoral and cellular autoimmune phenomena can be observed, and a pivotal role of T lymphocytes in SSc pathogenesis is postulated. The rarity of the disease, the wide spectrum of clinical manifestations and severity as well as a variable course render therapy in SSc a major challenge. In view of the immunopathogenesis of SSc, many (presumed) immunomodulatory agents have been used, but no single agent has been proven to be convincingly effective. Trials with extracorporeal therapies (such as photopheresis, plasmapheresis) or even stem cell transplantation are in progress. In contrast to the hitherto unsuccessful therapeutic approaches for the overall disease course, some life-threatening organ manifestations can often be treated successfully, e.g. interstitial pneumonitis with i.v. cyclophosphamide and scleroderma renal crisis with ACE inhibitors and haemodialysis, respectively. Furthermore, pharmacological and supportive treatment of Raynaud's phenomenon and gastrointestinal involvement can alleviate the burden of the disease. Current therapeutic options as well as hitherto investigated immunomodulators are reviewed in this article.

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.

[Pulmonary hypertension screening in systemic scleroderma: a cohort study of 67 patients]

PURPOSE

Pulmonary hypertension is a severe complication of systemic sclerosis and has emerged as a major cause of morbidity and mortality in this condition. Treatment is all the more efficient as pulmonary hypertension is early diagnosed. A good knowledge of the clinical, biological and functional features of pulmonary hypertension in systemic sclerosis is therefore necessary to suspect and to diagnose pulmonary hypertension as early as possible.

METHODS

Sixty seven patients with systemic sclerosis were retrospectively studied. We compared clinical, immunological, functional (spirometry) and morphological (pulmonary fibrosis) features according to the presence (n = 25) and the characteristic of pulmonary hypertension (isolated or secondary) or the absence (n = 42) of pulmonary hypertension, assessed by Doppler echocardiography.

RESULTS

CREST syndrome (calcinosis, Raynaud's phenomenon, oesophageal involvement, sclerodactyly and telangiectasia) was more frequent in patients with isolated pulmonary hypertension than in patients without PH (72.7% vs 28.5%, P < 0.05; odds-ratio [OR] = 6.6) and dyspnea was more severe (P < 0.001; OR = 11.4). The age at time of pulmonary hypertension diagnosis was higher in patients with secondary pulmonary hypertension than in patients with isolated from (median: 62.5 years (range: 32-35) vs 53 years (range: 37-85), P < 0.05). Patients with isolated pulmonary hypertension had anticardiolipin antibodies more frequently than patients without pulmonary hypertension (72.7% vs 35.7%, P < 0.05). Isolated reduction of diffusing capacity was preferentially observed among patients with isolated pulmonary hypertension than among those without pulmonary hypertension. A linear relation between systolic pulmonary artery pressure values and diffusing capacity values (r = 0.72, P < 0.01) was found. Isolated reduction of diffusing capacity was more frequent in patients with isolated pulmonary hypertension than in patients without pulmonary hypertension (63.6% vs 14.3%, P < 0.001; OR = 10.5).

CONCLUSION

The severity of pulmonary hypertension in systemic sclerosis justifies a systematic screening by Doppler echocardiography and diffusing capacity measurement. Our results allow us to better define the characteristics of sclerodermic patients with isolated or secondary pulmonary hypertension. The search for pulmonary hypertension should be repeated with time and clinicians should be particularly vigilant in the case of a patient presenting these characteristics.

Epoprostenol (prostacyclin) therapy in HIV-associated pulmonary hypertension

Although HIV-associated pulmonary hypertension and primary pulmonary hypertension (PPH) are clinically and histologically similar, treatment options for the former are limited. Treatment with calcium channel blockers (CCB), proven to be beneficial in a subset of patients with PPH, has been disappointing in HIV-associated pulmonary hypertension and there are no data examining the effects of long-term epoprostenol in this entity. Six patients with severe HIV-associated pulmonary hypertension were treated with continuous intravenous epoprostenol infusions. Acute infusion of epoprostenol resulted in a significant (p < 0.05) decrease in mean pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR) of 16. 4 and 32.7%, respectively, and a significant (p < 0.05) increase in mean cardiac output (CO) of 36.9%. At 1 yr, mean PAP and PVR had decreased by 21.7 and 54.9% (p < 0.05), respectively, and mean CO had increased by 51.4% (p < 0.05) when compared with baseline values. Repeat catheterizations of three patients at 2 yr and one patient at 40 mo demonstrated further improvement or maintenance of hemodynamics. In addition, NYHA functional class improved in all patients. We conclude that epoprostenol infusion is effective in improving hemodynamic and functional status in this cohort of six patients with HIV-associated pulmonary hypertension acutely and long-term.

Hemodynamic effects of epoprostenol in patients with systemic sclerosis and pulmonary hypertension

STUDY OBJECTIVES

To determine the cause of pulmonary hypertension (PH) in systemic sclerosis (SSc) patients since PH can occur because of pulmonary arteriopathy, pulmonary parenchymal destruction, and left ventricular cardiac dysfunction.

DESIGN AND SETTING

Consecutive case series in a university hospital.

PATIENTS

Nine SSc patients with PH (mean pulmonary artery pressure, 41 mm Hg), with (n = 6) or without (n = 3) concomitant interstitial lung disease (ILD).

METHODS

Acute infusion of epoprostenol was begun at 2 ng/kg/min and was titrated upward at a rate of 2 ng/kg/min every 30 min until symptomatic complications developed or pulmonary artery vascular resistance (PVR) was reduced by 50%.

RESULTS

Eight of nine patients demonstrated a reduction of > or = 20% in PVR, suggesting that vasoreactivity is common despite the presence of significant ILD. A single patient had no response to infusion with unchanged hemodynamics and oxygenation. One patient developed hypoxemia as cardiac output increased, suggesting a worsening of ventilation/perfusion matching or the presence of an anatomic shunt. Acute pulmonary edema developed in one patient at an infusion rate of 6 ng/kg/min. The results of cardiac catheterization suggested that pulmonary edema was caused by SSc heart disease.

CONCLUSION

SSc patients with ILD have diverse and sometimes multiple causes of PH that can be determined by short-term epoprostenol infusion. Beneficial effects can be obtained from epoprostenol despite extensive ILD.

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.

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.

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.

Successful treatment with immunosuppression, anticoagulation and vasodilator therapy of pulmonary hypertension in SLE associated with secondary antiphospholipid syndrome

Severe pulmonary hypertension (PHT) occurring in patients with systemic lupus erythematosus (SLE) is uncommon. Different modalities have been tried in the treatment for this condition but have not been effective because of progressive increase of pulmonary resistance over time. Our patient with SLE and PHT with antiphospholipid syndrome (APS), a condition which has previously never been described, responded rapidly to combination treatment with immunosuppression, anticoagulation and vasodilator therapy.