Gérald Simonneau

A Clinical Trial of Vena Caval Filters in the Prevention of Pulmonary Embolism in Patients with Proximal Deep-Vein Thrombosis

BACKGROUND The efficacy and safety of vena caval filters in the prevention of pulmonary embolism in patients with proximal deep-vein thrombosis is still a matter of debate. METHODS Using a two-by-two factorial design, we randomly assigned 400 patients with proximal deep-vein thrombosis who were at risk for pulmonary embolism to receive a vena caval filter (200 patients) or no filter (200 patients), and to receive low-molecular-weight heparin (enoxaparin, 195 patients) or unfractionated heparin (205 patients). The rates of recurrent venous thromboembolism, death, and major bleeding were analyzed at day 12 and at two years. RESULTS At day 12, two patients assigned to receive filters (1.1 percent), as compared with nine patients assigned to receive no filters (4.8 percent), had had symptomatic or asymptomatic pulmonary embolism (odds ratio, 0.22; 95 percent confidence interval, 0.05 to 0.90). At two years, 37 patients assigned to the filter group (20.8 percent), as compared with 21 patients assigned to the no-filter group (11.6 percent), had had recurrent deep-vein thrombosis (odds ratio, 1.87; 95 percent confidence interval, 1.10 to 3.20). There were no significant differences in mortality or the other outcomes. At day 12, three patients assigned to low-molecular-weight heparin (1.6 percent), as compared with eight patients assigned to unfractionated heparin (4.2 percent), had had symptomatic or asymptomatic pulmonary embolism (odds ratio, 0.38; 95 percent confidence interval, 0.10 to 1.38). CONCLUSIONS In high-risk patients with proximal deep-vein thrombosis, the initial beneficial effect of vena caval filters for the prevention of pulmonary embolism was counterbalanced by an excess of recurrent deep-vein thrombosis, without any difference in mortality. Our data also confirmed that low-molecular-weight heparin was as effective and safe as unfractionated heparin for the prevention of pulmonary embolism.

Effects of the dual endothelin-receptor antagonist bosentan in patients with pulmonary hypertension: a randomised placebocontrolled study

BACKGROUND Endothelin 1, a powerful endogenous vasoconstrictor and mitogen, might be a cause of pulmonary hypertension. We describe the efficacy and safety of bosentan, a dual endothelin-receptor antagonist that can be taken orally, in patients with severe pulmonary hypertension. METHODS In this double-blind, placebo-controlled study, 32 patients with pulmonary hypertension (primary or associated with scleroderma) were randomly assigned to bosentan (62.5mg taken twice daily for 4 weeks then 125 mg twice daily) or placebo for a minimum of 12 weeks. The primary endpoint was change in exercise capacity. Secondary endpoints included changes in cardiopulmonary haemodynamics, Borg dyspnoea index, WHO functional class, and withdrawal due to clinical worsening. Analysis was by intention to treat. FINDINGS In patients given bosentan, the distance walked in 6 min improved by 70 m at 12 weeks compared with baseline, whereas it worsened by 6 m in those on placebo (difference 76 m [95% CI 12-139], p=0.021). The improvement was maintained for at least 20 weeks. The cardiac index was 1.0 L min(-1) m(-2) (95% CI 0.6-1.4, p<0.0001) greater in patients given bosentan than in those given placebo. Pulmonary vascular resistance decreased by 223 dyn s cm(-)(5) with bosentan, but increased by 191 dyn s cm(-5) with placebo (difference -415 [-608 to -221], p=0.0002). Patients given bosentan had a reduced Borg dyspnoea index and an improved WHO functional class. All three withdrawals from clinical worsening were in the placebo group (p=0.033). The number and nature of adverse events did not differ between the two groups. INTERPRETATION Bosentan increases exercise capacity and improves haemodynamics in patients with pulmonary hypertension, suggesting that endothelin has an important role in pulmonary hypertension.

Pulmonary hypertension in patients with combined pulmonary fibrosis and emphysema syndrome

This study aims to describe the haemodynamic and survival characteristics of patients with pulmonary hypertension in the recently individualised syndrome of combined pulmonary fibrosis and emphysema. A retrospective multicentre study was conducted in 40 patients (38 males; age 68±9 yrs; 39 smokers) with combined pulmonary fibrosis and emphysema, and pulmonary hypertension at right heart catheterisation. Dyspnoea was functional class II in 15%, III in 55% and IV in 30%. 6-min walk distance was 244±126 m. Forced vital capacity was 86±18%, forced expiratory volume in 1 s 78±19%, and carbon monoxide diffusion transfer coefficient 28±16% of predicted. Room air arterial oxygen tension was 7.5±1.6 kPa (56±12 mmHg). Mean pulmonary artery pressure was 40±9 mmHg, cardiac index 2.5±0.7 L·min−1·m−2 and pulmonary vascular resistance 521±205 dyn·s·cm−5. 1-yr survival was 60%. Higher pulmonary vascular resistance, higher heart rate, lower cardiac index and lower carbon monoxide diffusion transfer were associated with shorter survival. Patients with combined pulmonary fibrosis and emphysema syndrome and pulmonary hypertension confirmed by right heart catheterisation have a dismal prognosis despite moderately altered lung volumes and flows and moderately severe haemodynamic parameters.

Survival in Patients With Idiopathic, Familial, and Anorexigen-Associated Pulmonary Arterial Hypertension in the Modern Management Era

Background— Novel therapies have recently become available for pulmonary arterial hypertension. We conducted a study to characterize mortality in a multicenter prospective cohort of patients diagnosed with idiopathic, familial, or anorexigen-associated pulmonary arterial hypertension in the modern management era. Methods and Results— Between October 2002 and October 2003, 354 consecutive adult patients with idiopathic, familial, or anorexigen-associated pulmonary arterial hypertension (56 incident and 298 prevalent cases) were prospectively enrolled. Patients were followed up for 3 years, and survival rates were analyzed. For incident cases, estimated survival (95% confidence intervals [CIs]) at 1, 2, and 3 years was 85.7% (95% CI, 76.5 to 94.9), 69.6% (95% CI, 57.6 to 81.6), and 54.9% (95% CI, 41.8 to 68.0), respectively. In a combined analysis population (incident patients and prevalent patients diagnosed within 3 years before study entry; n=190), 1-, 2-, and 3-year survival estimates were 82.9% (95% CI, 72.4 to 95.0), 67.1% (95% CI, 57.1 to 78.8), and 58.2% (95% CI, 49.0 to 69.3), respectively. Individual survival analysis identified the following as significantly and positively associated with survival: female gender, New York Heart Association functional class I/II, greater 6-minute walk distance, lower right atrial pressure, and higher cardiac output. Multivariable analysis showed that being female, having a greater 6-minute walk distance, and exhibiting higher cardiac output were jointly significantly associated with improved survival. Conclusions— In the modern management era, idiopathic, familial, and anorexigen-associated pulmonary arterial hypertension remains a progressive, fatal disease. Mortality is most closely associated with male gender, right ventricular hemodynamic function, and exercise limitation.

Chronic Thromboembolic Pulmonary Hypertension

Since the last World Symposium on Pulmonary Hypertension in 2008, we have witnessed numerous and exciting developments in chronic thromboembolic pulmonary hypertension (CTEPH). Emerging clinical data and advances in technology have led to reinforcing and updated guidance on diagnostic approaches to pulmonary hypertension, guidelines that we hope will lead to better recognition and more timely diagnosis of CTEPH. We have new data on treatment practices across international boundaries as well as long-term outcomes for CTEPH patients treated with or without pulmonary endarterectomy. Furthermore, we have expanded data on alternative treatment options for select CTEPH patients, including data from multiple clinical trials of medical therapy, including 1 recent pivotal trial, and compelling case series of percutaneous pulmonary angioplasty. Lastly, we have garnered more experience, and on a larger international scale, with pulmonary endarterectomy, which is the treatment of choice for operable CTEPH. This report overviews and highlights these important interval developments as deliberated among our task force of CTEPH experts and presented at the 2013 World Symposium on Pulmonary Hypertension in Nice, France.

Medical Therapy For Pulmonary Arterial Hypertension* ACCP Evidence-Based Clinical Practice Guidelines

Pulmonary arterial hypertension (PAH) is often difficult to diagnose and challenging to treat. Untreated, it is characterized by a progressive increase in pulmonary vascular resistance leading to right ventricular failure and death. The past decade has seen remarkable improvements in therapy, driven largely by the conduct of randomized controlled trials. Still, the selection of most appropriate therapy is complex, and requires familiarity with the disease process, evidence from treatment trials, complicated drug delivery systems, dosing regimens, side effects, and complications. This chapter will provide evidence-based treatment recommendations for physicians involved in the care of these complex patients. Due to the complexity of the diagnostic evaluation required, and the treatment options available, it is strongly recommended that consideration be given to referral of patients with PAH to a specialized center.

Long-term response to calcium-channel blockers in non-idiopathic pulmonary arterial hypertension

AIMS To assess the acute vasodilator response and long-term response to calcium-channel blockers (CCB) in pulmonary arterial hypertension (PAH) with associated conditions. METHODS AND RESULTS The response to acute vasodilator testing [>20% decrease in mean pulmonary artery pressure (mPAP) and total pulmonary resistance] was assessed in 663 consecutive PAH patients with connective tissue disease (CTD; n = 168), portal hypertension (PoPH; n = 153), anorexigen use (n = 127), human immunodeficiency virus infection (HIV; n = 124), congenital heart disease (CHD; n = 50), and pulmonary veno-occlusive disease or capillary haemangiomatosis (PVOD/PCH; n = 41). An acute vasodilator response was observed in 13.4% of PAH-anorexigen patients, 12.2% of PVOD/PCH, 10.1% of CTD, 1.6% of HIV, 1.3% of PoPH, and was absent in CHD. A long-term response to CCB (marked haemodynamic improvement at 3-4 months and New York Heart Association functional class I or II after 1 year) was reported in 9.4% of PAH-anorexigen patients but was rare in HIV, PoPH, CTD (1.6, 0.7, and 0.6%, respectively) and absent in PVOD/PCH. All patients with a long-term CCB response were alive after 5 years; two deaths not related to PAH occurred after this time. Recent criteria for acute response based on the fall in mPAP to <40 mmHg are more specific to detect long-term responders to CCB. CONCLUSION A long-term CCB response was reported in patients with PAH associated with anorexigen use, but was rare in patients with PoPH or HIV and absent in PVOD/PCH, CHD, and the vast majority of CTD. The prognosis of long-term responders was favourable and related to the underlying cause of PAH.

A comparison of low-molecular-weight heparin with unfractionated heparin for acute pulmonary embolism

BACKGROUND Low-molecular-weight heparin appears to be at least as effective and safe as standard, unfractionated heparin for the treatment of deep-vein thrombosis, but only limited data are available on the use of low-molecular-weight heparin to treat acute symptomatic pulmonary embolism. METHODS We randomly assigned 612 patients with symptomatic pulmonary embolism who did not require thrombolytic therapy or embolectomy to either subcutaneous low-molecular-weight heparin (tinzaparin) given once daily in a fixed dose or adjusted-dose, intravenous unfractionated heparin. Oral anticoagulant therapy was begun between the first and the third day and was given for at least three months. We compared the treatments at day 8 and day 90 with respect to a combined end point of recurrent thromboembolism, major bleeding, and death. RESULTS In the first eight days of treatment, 9 of 308 patients assigned to receive unfractionated heparin (2.9 percent) reached at least one of the end points, as compared,with 9 of 304 patients assigned to low-molecular-weight heparin (3.0 percent; absolute difference, 0.1 percentage point; 95 percent confidence interval, -2.7 to 2.6). By day 90, 22 patients assigned to unfractionated heparin (7.1 percent) and 18 patients assigned to low-molecular-weight heparin (5.9 percent) had reached at least one end point (P=0.54; absolute difference, 1.2 percentage points; 95 percent confidence interval, -2.7 to 5.1). The risk of major bleeding was similar in the two treatment groups throughout the study. CONCLUSIONS Under the conditions of this study, initial subcutaneous therapy with the low-molecular-weight heparin tinzaparin appeared to be as effective and safe as intravenous unfractionated heparin in patients with acute pulmonary embolism.

Tadalafil Therapy for Pulmonary Arterial Hypertension

Background— Treatment options for pulmonary arterial hypertension target the prostacyclin, endothelin, or nitric oxide pathways. Tadalafil, a phosphodiesterase type-5 inhibitor, increases cGMP, the final mediator in the nitric oxide pathway. Methods and Results— In this 16-week, double-blind, placebo-controlled study, 405 patients with pulmonary arterial hypertension (idiopathic or associated), either treatment-naive or on background therapy with the endothelin receptor antagonist bosentan, were randomized to placebo or tadalafil 2.5, 10, 20, or 40 mg orally once daily. The primary end point was the change from baseline to week 16 in the distance walked in 6 minutes. Changes in World Health Organization functional class, clinical worsening, and health-related quality of life were also assessed. Patients completing the 16-week study could enter a long-term extension study. Tadalafil increased the distance walked in 6 minutes in a dose-dependent manner; only the 40-mg dose met the prespecified level of statistical significance (P<0.01). Overall, the mean placebo-corrected treatment effect was 33 m (95% confidence interval, 15 to 50 m). In the bosentan-naive group, the treatment effect was 44 m (95% confidence interval, 20 to 69 m) compared with 23 m (95% confidence interval, −2 to 48 m) in patients on background bosentan therapy. Tadalafil 40 mg improved the time to clinical worsening (P=0.041), incidence of clinical worsening (68% relative risk reduction; P=0.038), and health-related quality of life. The changes in World Health Organization functional class were not statistically significant. The most common treatment-related adverse events reported with tadalafil were headache, myalgia, and flushing. Conclusions— In patients with pulmonary arterial hypertension, tadalafil 40 mg was well tolerated and improved exercise capacity and quality of life measures and reduced clinical worsening.

Treatment of patients with mildly symptomatic pulmonary arterial hypertension with bosentan (EARLY study): a double-blind, randomised controlled trial

BACKGROUND Treatments for pulmonary arterial hypertension have been mainly studied in patients with advanced disease (WHO functional class [FC] III and IV). This study was designed to assess the effect of the dual endothelin receptor antagonist bosentan in patients with WHO FC II pulmonary arterial hypertension. METHODS Patients with WHO FC II pulmonary arterial hypertension aged 12 years or over with 6-min walk distance of less than 80% of the normal predicted value or less than 500 m associated with a Borg dyspnoea index of 2 or greater were enrolled in this double-blind, placebo-controlled, multicentre trial. 185 patients were randomly assigned to receive bosentan (n=93) or placebo (n=92) for the 6-month double-blind treatment period via a centralised integrated voice recognition system. Primary endpoints were pulmonary vascular resistance at month 6 expressed as percentage of baseline and change from baseline to month 6 in 6-min walk distance. Analyses of the primary endpoints were done with all randomised patients who had a valid baseline assessment and an assessment or an imputed value for month 6. This trial was registered with ClinicalTrials.gov, number NCT00091715. FINDINGS Analyses were done with 168 patients (80 in the bosentan group, 88 in the placebo group) for pulmonary vascular resistance and with 177 (86 and 91) for 6-min walking distance. At month 6, geometric mean pulmonary vascular resistance was 83.2% (95% CI 73.8-93.7) of the baseline value in the bosentan group and 107.5% (97.6-118.4) of the baseline value in the placebo group (treatment effect -22.6%, 95% CI -33.5 to -10.0; p<0.0001). Mean 6-min walk distance increased from baseline in the bosentan group (11.2 m, 95% CI -4.6 to 27.0) and decreased in the placebo group (-7.9 m, -24.3 to 8.5), with a mean treatment effect of 19.1 m (95% CI 3.6-41.8; p=0.0758). 12 (13%) patients in the bosentan group and eight (9%) in the placebo group reported serious adverse events, the most common of which were syncope in the bosentan group and right ventricular failure in the placebo group. INTERPRETATION Bosentan treatment could be beneficial for patients with WHO FC II pulmonary arterial hypertension.