Andrew Hirsch

Tiotropium in Combination with Placebo, Salmeterol, or Fluticasone–Salmeterol for Treatment of Chronic Obstructive Pulmonary Disease: A Randomized Trial

Context Physicians use multiple medications to treat chronic obstructive pulmonary disease (COPD). Contribution In this multicenter trial, 449 adults with moderate or severe COPD were randomly assigned to receive tiotropium and placebo, tiotropium and salmeterol, or tiotropium and fluticasonesalmeterol for 1 year. About 63%, 65%, and 60% of patients, respectively, had exacerbations. The third group, but not the second group, had better lung function and fewer hospitalizations than the first group. Caution Many patients discontinued assigned medications. Implications Adding fluticasonesalmeterol to tiotropium may improve lung function and decrease hospitalizations, but it does not affect reduce exacerbations in patients with moderate or severe COPD. The Editors Most patients with moderate or severe chronic obstructive pulmonary disease (COPD) experience chronic progressive dyspnea that is not alleviated by short-acting bronchodilators. It is therefore not surprising that many patients are treated with multiple inhaled medications to optimize their lung function and minimize symptoms (1). Published guidelines on COPD state that the goals of pharmacologic therapy should be to control symptoms, improve health status, and reduce the frequency of COPD exacerbations (2, 3), and many published guidelines advocate combining different classes of long-acting bronchodilators or inhaled steroids to achieve these goals (2, 3). In the past several years, several studies have shown that treatment of COPD with the long-acting anticholinergic tiotropium (47); the long-acting 2-agonist salmeterol (810); or products that combine inhaled steroids and long-acting 2-agonists, such as fluticasonesalmeterol or budesonideformoterol (1114), improve dyspnea and quality of life and decrease exacerbation rates compared with placebo. However, no studies have assessed whether therapy with a combination of these products provides greater clinical benefit than does therapy with these agents used alone. 2-Agonists and anticholinergics work by different mechanisms to cause bronchodilation (15), and inhaled corticosteroids may have an anti-inflammatory effect in COPD (16). Thus, it makes theoretical and intuitive sense that combining these therapies might be more beneficial than therapy with 1 agent alone. However, safety concerns, such as side effects associated with long-term use of long-acting 2-agonists and inhaled corticosteroids, and economic issues related to the additional costs of these medications may argue against routine use of inhaled medication polypharmacy without evidence of efficacy. We therefore conducted a randomized, double-blind, placebo-controlled clinical trial to determine whether combining tiotropium with salmeterol or fluticasonesalmeterol produces greater improvements in clinical outcomes for adults with moderate or severe COPD compared with tiotropium therapy alone. Methods Design We designed a parallel-group, 3-group, randomized, double-blind, placebo-controlled trial in patients with moderate or severe COPD that was conducted from October 2003 to January 2006. The study protocol has been published elsewhere (17). The research ethics boards of all participating centers approved the study, and all trial participants provided written informed consent. Setting and Participants We enrolled patients with diagnosed moderate or severe COPD from 27 Canadian medical centers. Twenty centers were academic hospitalbased pulmonary clinics, 5 were community-based pulmonary clinics, and 2 were community-based primary care clinics. Eligible patients had to have had at least 1 exacerbation of COPD that required treatment with systemic steroids or antibiotics within the 12 months before randomization. Additional inclusion criteria were age older than 35 years; a history of 10 pack-years or more of cigarette smoking; and documented chronic airflow obstruction, with an FEV1FVC ratio less than 0.70 and a postbronchodilator FEV1 less than 65% of the predicted value. We excluded patients with a history of physician-diagnosed asthma before 40 years of age; those with a history of physician-diagnosed chronic congestive heart failure with known persistent severe left ventricular dysfunction; those receiving oral prednisone; those with a known hypersensitivity or intolerance to tiotropium, salmeterol, or fluticasonesalmeterol; those with a history of severe glaucoma or severe urinary tract obstruction, previous lung transplantation or lung volume reduction surgery, or diffuse bilateral bronchiectasis; and those who were pregnant or were breastfeeding. Persons with a recent COPD exacerbation requiring oral or intravenous antibiotics or steroids were required to wait until treatment with these agents had been discontinued for 28 days before entering the study. Randomization and Interventions We randomly assigned patients to 1 of 3 treatment groups for 52 weeks: tiotropium (Spiriva [Boehringer Ingelheim Pharma, Ingelheim, Germany]), 18 g once daily, plus placebo inhaler, 2 puffs twice daily; tiotropium, 18 g once daily, plus salmeterol (Serevent [GlaxoSmithKline, Research Triangle Park, North Carolina]), 25 g/puff, 2 puffs twice daily; or tiotropium, 18 g once daily, plus fluticasonesalmeterol (Advair [GlaxoSmithKline]), 250/25 g/puff, 2 puffs twice daily. Randomization was done through central allocation of a randomization schedule that was prepared from a computer-generated random listing of the 3 treatment allocations, blocked in variable blocks of 9 or 12 and stratified by site. Neither research staff nor patients were aware of the treatment assignment before or after randomization. All study patients were provided with inhaled albuterol and were instructed to use it when necessary to relieve symptoms. Any treatment with inhaled corticosteroids, long-acting 2-agonists, and anticholinergics that the patient may have been using before entry was discontinued on entry into the study. Therapy with other respiratory medications, such as oxygen, antileukotrienes, and methylxanthines, was continued in all patient groups. Tiotropium was administered by using a Handihaler device (Boehringer Ingelheim). Study drugs were administered through a pressurized metered-dose inhaler using a spacer device (Aerochamber Plus, Trudell Medical, London, Ontario, Canada), and patients were taught the correct inhalation technique to ensure adequate drug delivery. The metered-dose inhalers containing placebo, salmeterol, and fluticasonesalmeterol were identical in taste and appearance, and they were enclosed in identical tamper-proof blinding devices. The medication canisters within the blinding devices were stripped of any identifying labeling. Adherence to therapy was assessed by weighing the returned inhaler canisters. Measurements and Outcomes The primary outcome was the proportion of patients in each treatment group who experienced a COPD exacerbation within 52 weeks of randomization. Respiratory exacerbations were defined, according to the 2000 Aspen Lung Conference Consensus definition, as a sustained worsening of the patients respiratory condition, from the stable state and beyond normal day-to-day variations, necessitating a change in regular medication in a patient with underlying COPD (18). An acute change in regular COPD medications was defined as physician-directed, short-term use of oral or intravenous steroids, oral or intravenous antibiotics, or both therapies. Secondary outcomes were the mean number of COPD exacerbations per patient-year; the total number of exacerbations that resulted in urgent visits to a health care provider or emergency department; the number of hospitalizations for COPD; the total number of hospitalizations for all causes; and changes in health-related quality of life, dyspnea, and lung function. Health-related quality of life was assessed by using the St. Georges Respiratory Questionnaire (19), dyspnea was assessed by using the Transitional Dyspnea Index (20) and the dyspnea domain of the Chronic Respiratory Disease Questionnaire (21), and lung function was assessed by measuring the FEV1 according to established criteria of the American Thoracic Society. Follow-up Procedures Patients were monitored for exacerbations by monthly telephone calls. Exacerbations and all secondary outcomes were also assessed through patient visits at baseline and at 4, 20, 36, and 52 weeks after randomization. For every suspected exacerbation, we contacted both the patient and the patients treating physician to ensure that the medical encounter had been prompted by acute respiratory symptoms and a full report, including physician, emergency department, and hospital records that described the circumstances of each suspected exacerbation, was prepared. The assembled data from the visit for the suspected exacerbation were presented to a blinded adjudication committee for review, and the committee confirmed whether the encounter met the study definition of COPD exacerbation. For the purposes of the trial, we considered that a patient had experienced a new COPD exacerbation if he or she had not been receiving oral steroids and antibiotics for at least 14 days after the previous exacerbation. Patients were followed for the full 52-week duration of the trial, and primary and secondary outcomes were recorded throughout the 1-year period regardless of whether patients had experienced an exacerbation or discontinued treatment with study medications. We did not break the study blinding for patients who prematurely discontinued treatment with study medications. Adverse events were captured by the research coordinators through monthly patient telephone interviews and at scheduled patient visits by using checklists of potential side effects. Physicians rated events as expected or unexpected, and they were asked to rate event severity and attribute causality of adverse events to the study drugs. Statistical Analysis We designed the study to detect an 18% absolute d

Computed Tomographic Pulmonary Angiography vs Ventilation-Perfusion Lung Scanning in Patients With Suspected Pulmonary Embolism: A Randomized Controlled Trial

CONTEXTnVentilation-perfusion (V(dot)Q(dot) lung scanning and computed tomographic pulmonary angiography (CTPA) are widely used imaging procedures for the evaluation of patients with suspected pulmonary embolism. Ventilation-perfusion scanning has been largely replaced by CTPA in many centers despite limited comparative formal evaluations and concerns about CTPAs low sensitivity (ie, chance of missing clinically important pulmonary embuli).nnnOBJECTIVESnTo determine whether CTPA may be relied upon as a safe alternative to V(dot)Q(dot scanning as the initial pulmonary imaging procedure for excluding the diagnosis of pulmonary embolism in acutely symptomatic patients.nnnDESIGN, SETTING, AND PARTICIPANTSnRandomized, single-blinded noninferiority clinical trial performed at 4 Canadian and 1 US tertiary care centers between May 2001 and April 2005 and involving 1417 patients considered likely to have acute pulmonary embolism based on a Wells clinical model score of 4.5 or greater or a positive D-dimer assay result.nnnINTERVENTIONnPatients were randomized to undergo either V(dot)Q(dot scanning or CTPA. Patients in whom pulmonary embolism was considered excluded did not receive antithrombotic therapy and were followed up for a 3-month period.nnnMAIN OUTCOME MEASUREnThe primary outcome was the subsequent development of symptomatic pulmonary embolism or proximal deep vein thrombosis in patients in whom pulmonary embolism had initially been excluded.nnnRESULTSnSeven hundred one patients were randomized to CTPA and 716 to V(dot)Q(dot scanning. Of these, 133 patients (19.2%) in the CTPA group vs 101 (14.2%) in the V(dot)Q(dot scan group were diagnosed as having pulmonary embolism in the initial evaluation period (difference, 5.0%; 95% confidence interval [CI], 1.1% to 8.9%) and were treated with anticoagulant therapy. Of those in whom pulmonary embolism was considered excluded, 2 of 561 patients (0.4%) randomized to CTPA vs 6 of 611 patients (1.0%) undergoing V(dot)Q(dot scanning developed venous thromboembolism in follow-up (difference, -0.6%; 95% CI, -1.6% to 0.3%) including one patient with fatal pulmonary embolism in the V(dot)Q(dot group.nnnCONCLUSIONSnIn this study, CTPA was not inferior to V(dot)Q(dot scanning in ruling out pulmonary embolism. However, significantly more patients were diagnosed with pulmonary embolism using the CTPA approach. Further research is required to determine whether all pulmonary emboli detected by CTPA should be managed with anticoagulant therapy.nnnTRIAL REGISTRATIONnisrctn.org Identifier: ISRCTN65486961.

Six-month exercise training program to treat post-thrombotic syndrome: a randomized controlled two-centre trial

Background Exercise training may have the potential to improve post-thrombotic syndrome, a frequent, chronic complication of deep venous thrombosis. We conducted a randomized controlled two-centre pilot trial to assess the feasibility of a multicentre-based evaluation of a six-month exercise training program to treat post-thrombotic syndrome and to obtain preliminary data on the effectiveness of such a program. Methods Patients were randomized to receive exercise training (a six-month trainer-supervised program) or control treatment (an education session with monthly phone follow-ups). Levels of eligibility, consent, adherence and retention were used as indicators of study feasibility. Primary outcomes were change from baseline to six months in venous disease-specific quality of life (as measured using the Venous Insufficiency Epidemiological and Economic Study Quality of Life [VEINES-QOL] questionnaire) and severity of post-thrombotic syndrome (as measured by scores on the Villalta scale) in the exercise training group versus the control group, assessed by t tests. Secondary outcomes were change in generic quality of life (as measured using the Short-Form Health Survey-36 [SF-36] questionnaire), category of severity of post-thrombotic syndrome, leg strength, leg flexibility and time on treadmill. Results Of 95 patients with post-thrombotic syndrome, 69 were eligible, 43 consented and were randomized, and 39 completed the study. Exercise training was associated with improvement in VEINES-QOL scores (exercise training mean change 6.0, standard deviation [SD] 5.1 v. control mean change 1.4, SD 7.2; difference 4.6, 95% CI 0.54 to 8.7; p = 0.027) and improvement in scores on the Villalta scale (exercise training mean change −3.6, SD 3.7 v. control mean change −1.6, SD 4.3; difference −2.0, 95% CI −4.6 to 0.6; p = 0.14). Most secondary outcomes also showed greater improvement in the exercise training group. Interpretation Exercise training may improve post-thrombotic syndrome. It would be feasible to definitively evaluate exercise training as a treatment for post-thrombotic syndrome in a large multicentre trial.

Effect of chronic infusion of Epoprostenol on echocardiographic right ventricular myocardial performance index and its relation to clinical outcome in patients with primary pulmonary hypertension

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Pulmonary capillary endothelial metabolic dysfunction: Severity in pulmonary arterial hypertension related to connective tissue disease versus idiopathic pulmonary arterial hypertension

OBJECTIVEnPulmonary endothelial dysfunction is intertwined with the development and progression of pulmonary arterial hypertension (PAH). Pulmonary endothelium is an active metabolic tissue in healthy human subjects. This study was undertaken to determine the effects of PAH on pulmonary endothelial angiotensin-converting enzyme (ACE) activity and to identify differences between common PAH types, i.e., PAH related to connective tissue disease (PAH-CTD) versus idiopathic PAH (IPAH).nnnMETHODSnNineteen patients with PAH-CTD, 25 patients with IPAH, and 23 control subjects were evaluated. The single-pass transpulmonary percent metabolism (%M) and hydrolysis (both reflecting enzyme activity per capillary) of an ACE synthetic substrate were determined. In addition, the calculated functional capillary surface area (FCSA), normalized to body surface area (BSA), was determined.nnnRESULTSnThe %M values in patients with PAH-CTD (mean+/-SEM 53.6+/-3.6%) were significantly reduced compared with those in control subjects (P<0.01) and those in patients with IPAH (P<0.03), but were similar between the IPAH and control groups (mean+/-SEM 66.2+/-3.6% and 74.7+/-2.7%, respectively). Substrate hydrolysis was also significantly reduced in patients with PAH-CTD. The FCSA/BSA was significantly reduced in patients with PAH-CTD (mean+/-SEM 1,068+/-118 ml/minute/m2) and in patients with IPAH (1,443+/-186 ml/minute/m2) compared with that in controls (2,948+/-245 ml/minute/m2; P<0.01 for both). At a given cardiac index, the FCSA/BSA tended to be lower in the PAH-CTD group than in the IPAH group. Moreover, unlike in IPAH, a linear relationship between the FCSA/BSA and the diffusing capacity for carbon monoxide (DLCO) was observed in PAH-CTD (r=0.54, P<0.03).nnnCONCLUSIONnThe metabolically functional pulmonary capillary bed appears to be reduced to an equal extent in PAH-CTD and IPAH. However, %M and hydrolysis appear to be reduced in PAH-CTD but not in IPAH, reflecting relatively diminished ACE activity on the pulmonary capillary endothelial cells of patients with PAH-CTD, and showing that pulmonary endothelial metabolic function differs between PAH types. This study also provides the first functional evidence that a reduced DLCO value in patients with PAH-CTD is related to the degree of FCSA loss.

Effect of graduated elastic compression stockings on leg symptoms and signs during exercise in patients with deep venous thrombosis: a randomized cross-over trial.

Summary.u2003 Graduated elastic compression stockings (ECS) are often prescribed after deep venous thrombosis (DVT) to alleviate acute symptoms and to prevent and treat post‐thrombotic syndrome (PTS). In patients with DVT, leg symptoms tend to worsen with exercise. The effects of ECS use during exercise have not been studied. Objectives were to determine whether ECS improve symptoms and signs and increase exercise capacity when worn during treadmill exercise by patients with prior DVT, with or without PTS. The methods employed a randomized cross‐over trial. We recruited subjects who had a first episode of unilateral DVT at least 1u2003year earlier and categorized them as having, or not having, the PTS using a validated scale. Subjects underwent two identical treadmill exercise sessions at least 1u2003week apart, and were randomly assigned to wear knee‐length 30u2003mmHg ECS on the affected leg during one of the two sessions. Venous symptoms, leg volume, leg circumference and calf muscle flexibility were measured in the affected leg before and after both exercise sessions. Subjects achieved similar percentage maximum predicted heart rates during both sessions. Comparing the ECS to no ECS session, there were no significant differences in treadmill time (21.2 vs. 21.2u2003min, Pu2003=u20030.94), gain in leg volume (71 vs. 73 mL, Pu2003=u20030.83), or change in soleus or gastrocnemius flexibility, whether or not PTS was present. Symptoms in general worsened slightly with exercise regardless of whether or not ECS were worn and did not differ according to PTS status. Per‐subject analysis showed that use of ECS resulted in global improvement of symptoms in 25% of subjects, global worsening in 33% of subjects, and had no or inconsistent effects in 42% of subjects. Whether or not PTS was present, the use of ECS during exercise by patients with prior DVT did not improve symptoms and signs during exercise or increase exercise capacity.

Prevalence and impact of coronary artery disease in patients with pulmonary arterial hypertension.

The occurrence and impact of coronary artery disease (CAD) among patients with pulmonary arterial hypertension (PAH) are unknown. We aimed to determine the prevalence, clinical correlates, and effect of CAD in patients with PAH. We reviewed the medical records of consecutive patients diagnosed with PAH at a university-based referral center for pulmonary vascular disease from January 1990 to May 2010. The patients systematically underwent right heart catheterization and coronary angiography as a part of their evaluation. The patients with PAH with CAD (defined as ≥50% stenosis in ≥1 major epicardial coronary artery) were compared to patients without CAD. Among the 162 patients with PAH, the prevalence of CAD was 28.4%. The presence of CAD was associated with older age (66.6 ± 11.5 vs 49.2 ± 14.0 years, p <0.001), systemic hypertension, and dyslipidemia. The patients with PAH and CAD had a lower mean pulmonary arterial pressure (44.6 ± 11.1 vs 49.2 ± 14.0 mm Hg; p = 0.02) than patients without CAD. During a median follow-up of 36 months, 73 patients died. The presence of CAD was a predictor of all-cause mortality on univariate analysis (hazard ratio 1.97, 95% confidence interval 1.21 to 3.20) but not on multivariate analysis, which identified older age (hazard ratio 1.03, 95% confidence interval 1.01 to 1.05) and right atrial pressure (hazard ratio 1.08, 95% confidence interval 1.03 to 1.14) as the only independent predictors. In conclusion, our study has demonstrated that CAD is common among patients with PAH. CAD prevalence increases with age, dyslipidemia, and hypertension, but we did not detect an independent prognostic effect of CAD on mortality.

Pulmonary capillary endothelial metabolic function in chronic thromboembolic pulmonary hypertension

Summary.u2002 Background:u2002Chronic thromboembolic pulmonary hypertension (CTEPH) causes physical plugging of large pulmonary arteries as well as a distal micro‐vasculopathy. Pulmonary endothelium is an active metabolic tissue in normal humans. The effects of CTEPH on pulmonary endothelial metabolism are unknown. Objectives:u2002We studied pulmonary capillary endothelium‐bound angiotensin converting enzyme (ACE) activity as an index of endothelial metabolism in patients with CTEPH. Patients/methods:u2002We measured single‐pass transpulmonary per cent metabolism (%M) and hydrolysis of an ACE synthetic substrate and calculated functional capillary surface area (FCSA), normalized to body surface area (BSA), in 13 patients with CTEPH and 23 controls. Results:u2002Mean %M for CTEPH (71.6u2003±u20034.0% SE) was similar to controls (74.7u2003±u20032.7%). Substrate hydrolysis (v) was similar for CTEPH (1.47u2003±u20030.22) and controls (1.51u2003±u20030.11). However, FCSA/BSA was reduced (Pu2003<u20030.01) for CTEPH (1530u2003±u2003218u2003mLu2003min−1*m−2) as compared with controls (2948u2003±u2003245). Conclusions:u2002The metabolically functional pulmonary capillary bed is reduced in CTEPH. However, because %M and hydrolysis are preserved, this points to a reduction in functional capillary surface area rather than reduced ACE activity on the pulmonary capillary endothelial cell. The reduction in functional capillary surface area may just be a result of decreased capillary recruitment because of upstream vascular plugging by chronic organized thrombus.

Step climbing capacity in patients with pulmonary hypertension.

BackgroundPatients with pulmonary hypertension (PH) typically have exercise intolerance and limitation in climbing steps.ObjectivesTo explore the exercise physiology of step climbing in PH patients, on a laboratory-based step test.MethodsWe built a step oximetry system from an ‘aerobics’ step equipped with pressure sensors and pulse oximeter linked to a computer. Subjects mounted and dismounted from the step until their maximal exercise capacity or 200 steps was achieved. Step-count, SpO2 and heart rate were monitored throughout exercise and recovery. We derived indices of exercise performance, desaturation and heart rate. A 6-min walk test and serum NT-proBrain Natriuretic Peptide (BNP) level were measured. Lung function tests and hemodynamic parameters were extracted from the medical record.ResultsEighty-six subjects [52 pulmonary arterial hypertension (PAH), 14 chronic thromboembolic PH (CTEPH), 20 controls] were recruited. Exercise performance (climbing time, height gained, velocity, energy expenditure, work-rate and climbing index) on the step test was significantly worse with PH and/or worsening WHO functional class (ANOVA, pxa0<xa00.001). There was a good correlation between exercise performance on the step and 6-min walking distance–climb index (rxa0=xa0−0.77, pxa0<xa00.0001). The saturation deviation (mean of SpO2 values <95xa0%) on the step test correlated with diffusion capacity of the lung (ρxa0=xa0−0.49, pxa0=xa00.001). No correlations were found between the step test indices and other lung function tests, hemodynamic parameters or NT-proBNP levels.ConclusionsPatients with PAH/CTEPH have significant limitation in step climbing ability that correlates with functional class and 6-min walking distance. This is a significant impediment to their daily activities.

Hemodynamic Stability After Transitioning Between Endothelin Receptor Antagonists in Patients With Pulmonary Arterial Hypertension

BACKGROUNDnMaintenance of a favourable hemodynamic profile is central to therapeutic success in pulmonary arterial hypertension (PAH). There is little information about the safety of transitioning patients between oral therapies for PAH. Endothelin receptor antagonists (ERAs) have been a therapeutic mainstay in PAH, providing benefit to many patients. Three ERAs, bosentan, sitaxsentan, and ambrisentan have been approved for clinical use. Sitaxsentan was voluntarily withdrawn from the market in late 2010 resulting in the need to quickly transition a large number of stable patients.nnnMETHODSnWe transitioned 30 clinically stable patients to either ambrisentan or bosentan. Patients underwent a right heart catheterization, measurement of serum N-terminal pro-brain natriuretic peptide (NT-proBNP), and assessment of functional class before changing ERA and again 4 months later. We present a retrospective analysis of those data.nnnRESULTSnOf the 30 patients transitioned (15 to ambrisentan, 15 to bosentan), 23 had complete hemodynamic data. No significant change was observed in the groups in right atrial, mean pulmonary artery, and pulmonary artery wedge pressures, or in cardiac output, pulmonary vascular resistance, or NT-proBNP levels. There was no change in World Health Organization functional class. Four ambrisentan and 2 bosentan-treated patients reported fluid retention, and 3 bosentan-treated patients had elevation of hepatic transaminases. Two of the patients had a right atrial pressure increase of ≥5 mm Hg, and 4 had pulmonary artery wedge pressure increase of ≥5 mm Hg.nnnCONCLUSIONSnTransitioning between ERAs in stable PAH patients does not result in hemodynamic or clinical deterioration during the first 4 months posttransition. A minority of patients have developed increased cardiac filling pressures.