Registry and Survival Study in Chinese Patients With Idiopathic and Familial Pulmonary Arterial Hypertension

Survival benefits of warfarin in Korean patients with idiopathic pulmonary arterial hypertension

BACKGROUND/AIMS

Idiopathic pulmonary arterial hypertension (IPAH) is an incurable disease with high mortality. Although most studies recommend anticoagulation treatment for IPAH, the benefits are uncertain, particularly in Korea, where it has not been studied. The purpose of this study was to evaluate survival outcomes of Korean patients with IPAH treated with warfarin.

METHODS

We performed a retrospective cohort study of patients diagnosed previously with pulmonary arterial hypertension (PAH) at the Asan Medical Center in Korea, between January 1994 and February 2013. We excluded patients with associated PAH, patients who did not undergo right heart catheterization (RHC), and patients with a positive vasoreactivity test. Patients in the study cohort were classified into a "warfarin group" and a "non-warfarin group," according to the treatment they received during the first year after diagnosis.

RESULTS

We identified 31 patients with IPAH and a negative vasoreactivity test on RHC. Median patient age was 36.0 years, and 23 patients (74.2%) were female. The median time from the onset of symptoms to diagnosis was 19.0 months, and the most common presenting symptom was dyspnea. Survival rates of the patients at 1, 3, 5, and 10 years were 90.2%, 79.5%, 62.7%, and 34.8%, respectively. The mean survival period was 12.0 years in the warfarin group and 6.1 years in the non-warfarin group. Warfarin treatment had significant survival benefits in patients with IPAH (p = 0.023).

CONCLUSIONS

Warfarin treatment substantially improved survival outcomes in Korean cases of IPAH.

Baseline Characteristics of the Korean Registry of Pulmonary Arterial Hypertension

Despite recent advances in understanding of the pathobiology and targeted treatments of pulmonary arterial hypertension (PAH), epidemiologic data from large populations have been limited to western countries. The aim of the Korean Registry of Pulmonary Arterial Hypertension (KORPAH) was to examine the epidemiology and prognosis of Korean patients with PAH. KORPAH was designed as a nationwide, multicenter, prospective data collection using an internet webserver from September 2008 to December 2011. A total of 625 patients were enrolled. The patients' mean age was 47.6 ± 15.7 yr, and 503 (80.5%) were women. The diagnostic methods included right heart catheterization (n = 249, 39.8%) and Doppler echocardiography (n = 376, 60.2%). The etiologies, in order of frequency, were connective tissue disease (CTD), congenital heart disease, and idiopathic PAH (IPAH) (49.8%, 25.4%, and 23.2%, respectively). Patients with WHO functional class III or IV at diagnosis were 43.4%. In total, 380 (60.8%) patients received a single PAH-specific treatment at the time of enrollment, but only 72 (18.9%) patients received combination therapy. Incident cases during the registry represented 297 patients; therefore, the incidence rate of PAH was 1.9 patients/yr/million people. The 1st-, 2nd-, and 3rd-yr estimated survival rates were 90.8%, 87.8%, and 84.4%, respectively. Although Korean PAH patients exhibited similar age, gender, and survival rate compared with western registries, they showed relatively more CTD-PAH in the etiology and also systemic lupus erythematosus among CTD-PAH. The data suggest that earlier diagnosis and more specialized therapies should be needed to improve the survival of PAH patients.

NSFC spurs significant basic research progress of respiratory medicine in China

Over the years, research in respiratory medicine has progressed rapidly in China. This commentary narrates the role of the National Natural Science Foundation of China (NSFC) in supporting the basic research of respiratory medicine, summarizes the major progress of respiratory medicine in China, and addresses the main future research directions sponsored by the NSFC.

Saudi experience in the management of pulmonary arterial hypertension; the outcome of PAH therapy with the exclusion of chronic parenteral prostacyclin

AIMS

The purpose of this study is to present our center's experience in managing patients with pulmonary arterial hypertension (PAH). The main objective is to describe patients' management profile and treatment outcome.

METHODS

This study presents the results from a single pulmonary hypertension (PH) specialized center in Saudi Arabia. Both incidence and prevalence cases are included. We have previously reported the clinical and physiological characteristics at the time of diagnosis for this cohort of patients. In this study, we describe the clinical management and the outcome of therapy in the same cohort, who were prospectively followed for a mean of 22 months.

RESULTS

A total of 107 patients were identified as having PAH. At the time of enrollment, 56.1% of patients were in modified New York Heart Association functional class (NYHA FC) III and 16.8% were in IV. Phosphdiesterase-5 inhibitor was the most commonly used target therapy (82.2%) followed by endothelin receptors antagonist (74.4%). Only five patients (4.7%) were candidate to use calcium channel blockers. Seventy-nine patients (73.8 %) received a combination nonparenteral target therapy. Thirty-one patients (28.9%) died during the follow-up period. Modified NYHA FC III and IV patients, portopulmonary hypertension, heritable PAH, and PAH associated with connective tissue diseases had the highest mortality rate (P < 0.001).

CONCLUSION

Our patients are detected at advanced stage of the disease, and thus the mortality is still unacceptably high. Advanced functional class at presentation and certain disease subgroups are associated with increased mortality.

Management of Crashing Patients with Pulmonary Hypertension

Critically ill patients with pulmonary hypertension (PH) often seem well, but they can decompensate dramatically in a short time. PH has several causes, classes, and complications; but the natural progression eventually leads to right ventricular failure, which can be extraordinarily difficult to manage. The purpose of this review is to discuss the causes, signs, and symptoms of PH as well as its management strategies and emergent complications. Treatment options are often limited, so it is imperative that the emergency department physician can recognize and manage these patients in a timely fashion.

Validation of two predictive models for survival in pulmonary arterial hypertension

The French Pulmonary Hypertension Network (FPHN) registry and the Registry to Evaluate Early And Long-term Pulmonary Arterial Hypertension Disease Management (REVEAL) have developed predictive models for survival in pulmonary arterial hypertension (PAH). In this collaboration, we assess the external validity (or generalisability) of the FPHN ItinérAIR-HTAP predictive equation and the REVEAL risk score calculator.

Validation cohorts approximated the eligibility criteria defined for each model. The REVEAL cohort comprised 292 treatment-naïve, adult patients diagnosed <1 year prior to enrolment with idiopathic, familial or anorexigen-induced PAH. The FPHN cohort comprised 1737 patients with group 1 PAH.

Application of FPHN parameters to REVEAL and REVEAL risk scores to FPHN demonstrated estimated hazard ratios that were consistent between studies and had high probabilities of concordance (hazard ratios of 0.72, 95% CI 0.64–0.80, and 0.73, 95% CI 0.70–0.77, respectively).

The REVEAL risk score calculator and FPHN ItinérAIR-HTAP predictive equation showed good discrimination and calibration for prediction of survival in the FPHN and REVEAL cohorts, respectively, suggesting prognostic generalisability in geographically different PAH populations. Once prospectively validated, these may become valuable tools in clinical practice.

A global perspective on the epidemiology of pulmonary hypertension

The epidemiology of pulmonary hypertension (PH) is not fully determined worldwide but is believed to vary in different regions of the world, with differences determined by genetic, geographic, environmental, and socioeconomic factors, as well as sex-related practices and inequities in access to health care. This article reviews the global epidemiology of PH, with emphasis on the prevalence, causes, forms, and underlying factors in the developing world. Left ventricular heart disease is the most common cause worldwide, but the main contributors in developing countries are chronic infectious diseases, hypertensive heart disease, cardiomyopathy, and rheumatic heart disease. Despite data suggesting a high prevalence in Sub-Saharan Africa, the available literature is very limited. International registries like the Pan African Pulmonary Hypertension Cohort are essential to provide information about the causes, comorbidities, and diagnostic classification, therapeutic management, and the natural course of PH worldwide. Moreover, there is a need to track diagnostic and management practices and challenges to identify the gaps and gradients between different regions of the world. The information gained will pinpoint areas for improvement, aiming at bridging the current divide between low-income and high-income countries.

Clinical characteristics and survival of Korean idiopathic pulmonary arterial hypertension patients based on vasoreactivity

We aimed to identify a vasoreactive subset of patients with idiopathic pulmonary arterial hypertension (IPAH) in Korea and to show their clinical characteristics and prognosis. Data on patients who were diagnosed with IPAH at Asan Medical Center between January 1994 and March 2013 were retrospectively collected. Acute vasodilator testing was performed with inhaled nitric oxide during diagnostic right heart catheterization. A positive acute response was defined as a reduction in mean pulmonary arterial pressure (PAP) ≥10 mmHg to an absolute level of mean PAP <40 mmHg without a decrease in cardiac output. Among a total of 60 IPAH patients included for analysis, 9 (15%) showed a positive acute response to acute vasodilator testing. Acute responders showed significantly lower peak velocity of a tricuspid regurgitation jet on echocardiography (4.1±0.3 m/s vs. 4.6±0.6 m/s; P=0.01) and significantly lower mean PAP hemodynamically (47±10 mmHg vs. 63±17 mmHg; P=0.003) than non-responders at baseline. The survival rate of acute responders was 88% at 1, 3, 5, and 10 yr, respectively, which was significantly higher than that of non-responders (85%, 71%, 55%, and 40%, respectively; P=0.029). In conclusion, Korean IPAH patients with vasoreactivity showed better baseline hemodynamic features and survival than those without vasoreactivity.

Gibbs J. The changing landscape of pulmonary arterial hypertension and implications for patient care

Registries have provided a wealth of information on the clinical and disease characteristics of patients living with pulmonary arterial hypertension (PAH) since the 1980s. Certain PAH demographics, such as the prevalence of various PAH subgroups and preponderance of female patients, appear to have remained stable over time. Contemporary registry data indicate that the average age of patients diagnosed with PAH has increased, at least in the Western world. Older patients with PAH are more likely to be diagnosed with a more advanced stage of the disease, have lower exercise capacity and present with multiple comorbidities. They also have worse survival compared with younger patients. Within the PAH population, there is also a subset of patients with a lower diffusing capacity of the lung for carbon monoxide who are generally older and display more severe disease characteristics. This review discusses the implications that the increased age of the PAH population at diagnosis has on the treatment and management of the disease, as well as the need for earlier and improved diagnosis in these patients.

Pulmonary arterial hypertension in Saudi Arabia: Patients' clinical and physiological characteristics and hemodynamic parameters. A single center experience

AIMS

The main objective of this study is to describe patients' clinical characteristics and physiological and hemodynamic parameters at the time of diagnosis in a pulmonary hypertension center in Saudi Arabia.

MATERIALS AND METHODS

This study reports the results from a single pulmonary hypertension specialized center in Riyadh, Saudi Arabia, namely Prince Sultan Medical Military City/Cardiac Center (PSMMC & CC). Both newly diagnosed (incidence) and referred (prevalence) cases of pulmonary arterial hypertension are included. All characteristics, including clinical, physiological, and hemodynamic parameters at the time of diagnosis are described.

RESULTS

A total of 107 patients were identified as having pulmonary arterial hypertension as diagnosed by right heart catheterization. The mean age at diagnosis was 36 (± 9) years, and there was a female preponderance of 62.6%. The mean duration between symptom onset and diagnosis was 27.8 (± 9.0) months. At the time of enrollment, 56.1% of patients were in functional class III and 16.8% were in functional class IV. Fifty five patients (51.4%) were diagnosed as idiopathic pulmonary arterial hypertension, 29 patients (27.1%) as congenital heart disease associated with pulmonary arterial hypertension, 16 patients (15.0%) as connective tissue diseases associated with pulmonary arterial hypertension, 4 patients (3.7%) as heritable pulmonary arterial hypertension, and 3 patients (2.8%) as portopulmonary hypertension.

CONCLUSION

This data highlights the current situation of pulmonary arterial hypertension in Saudi Arabia. Our patients are much younger than patients described in other international registries but still detected as late in the course of the disease. A majority of patients displays severe functional and hemodynamic compromise.

Association of Pulmonary Hypertension with Mortality in Incident Peritoneal Dialysis Patients

BACKGROUND

The prognostic value of pulmonary hypertension at the start of peritoneal dialysis (PD) in patient survival is unclear.

METHODS

We conducted a retrospective study of incident patients who initiated PD therapy from January 2007 to December 2011, and followed up through June 2013. Pulmonary hypertension was defined as an estimated systolic pulmonary artery pressure (PAP) of ≥ 35 mm Hg using echocardiography. Clinical parameters and laboratory findings were compared between patients with and without pulmonary hypertension and a logistic regression model was elaborated. Patient outcomes (all-cause and cardiovascular mortality) were recorded during follow-up. Survival curves were constructed by the Kaplan-Meier method, and the influences of pulmonary hypertension on outcomes were analyzed by Cox regression models.

RESULTS

Pulmonary hypertension was prevalent in 99 (16.0%) of the 618 patients studied. The independent risk factors for pulmonary hypertension were female (odds ratio [OR] = 2.12; 95% confidence interval [CI]: 1.29 - 3.46), left atrial diameter (OR = 1.15; 95% CI: 1.10 - 1.20), left ventricular ejection fraction (OR = 0.97; 95% CI: 0.95 - 0.99), and serum sodium (OR = 0.94; 95% CI: 0.89 - 0.99). Over a median follow-up of 29.4 months, 93 patients (15.0%) died, 59.1% of them due to cardiovascular disease. Kaplan-Meier survival analysis showed that patients with pulmonary hypertension had worse overall rates of survival and cardiovascular death-free survival than those without pulmonary hypertension. After multivariate adjustment, pulmonary hypertension was independently associated with increased risk for both all-cause and cardiovascular mortality, with hazard ratios (HRs) of 2.10 (95% CI: 1.35 - 3.27) and 2.60 (95% CI: 1.48 - 4.56), respectively.

CONCLUSIONS

The prevalence of pulmonary hypertension at the start of PD was common and associated with increased risk of both all-cause and cardiovascular mortality in incident PD patients.

Improved survival of Korean patients with idiopathic pulmonary arterial hypertension after the introduction of targeted therapies

OBJECTIVES

We compared the survival of patients with idiopathic pulmonary arterial hypertension (IPAH), receiving conventional and targeted therapies.

BACKGROUND

IPAH is an incurable disease with high mortality. To manage IPAH, several targeted therapies have been used in Korea.

METHODS

We performed a retrospective study of 71 patients diagnosed with IPAH in a tertiary hospital between January 1994 and February 2013. Patients were classified into "conventional therapy group" (treated with conventional therapies and/or beraprost) and "targeted therapy group" (treated with targeted therapies other than beraprost).

RESULTS

The median age of the patients was 33 years and 50 patients were female. The survival rate at 1, 3, 5, and 10 years was 80.1% 62.0%, 51.5%, and 26.8%, respectively. The survival rate in the targeted therapy group was greater than in the conventional therapy group (p-value = 0.026).

CONCLUSIONS

We believe targeted therapies would improve survival benefits in IPAH patients.

Epidemiology of pulmonary arterial hypertension

The epidemiology of pulmonary arterial hypertension (PAH) has changed over the last decade. Remarkable advances in understanding the pathobiology and clinical care required in PAH have resulted in improved quality of life and survival. Despite such important progress, the long-term rate of survival is still unacceptable. The epidemiology of PAH could not be easily generalized globally, due to the fact that nearly all of the present data has been gathered from Western, multicenter, prospective registries. There are potentially marked differences in PAH patients from Western and Eastern populations, and from developed and developing countries. Therefore, it is clear that more registry data will be needed to address novel questions emerging with improved knowledge of PAH.

Effects of the endothelin receptor antagonist bosentan on hemodynamics and exercise capacity in Japanese patients with mildly symptomatic pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) trial has mostly enrolled patients with World Health Organization functional class (WHO FC) III or IV. However, PAH is rapidly progressive in nature even in patients with less severe forms at diagnosis. Following the recent studies in Western population, here we assessed the efficacy of bosentan in Japanese patients with WHO FCII PAH. In this open-label trial, bosentan 125 mg twice daily was administered for 12 weeks in 16 patients, and a hemodynamic evaluation was performed. Treatment was continued for a further 12 weeks, where the effect on exercise capacity was assessed in 13 patients. In 16 patients, mean pulmonary arterial pressure decreased from 40.4 ± 10.4 to 35.6 ± 12.6 mmHg (p = 0.018) and cardiac index increased from 2.54 ± 0.73 to 2.96 ± 0.82 L/min/m(2) (p = 0.023). Thus, pulmonary vascular resistance decreased from 792 ± 565 to 598 ± 558 dyn·sec/cm(5) (p = 0.006). In 13 patients followed up for 24 weeks, 6-min walking distance increased from baseline at Week 12 (p = 0.003) and Week 24 (p = 0.011). All patients were mildly symptomatic at baseline with dyspnea index (Borg scale) of 2.50 ± 1.58 and the specific activity scale (SAS) of 5.0 ± 1.4 METs. These values remained unchanged throughout the study. These results suggest that bosentan treatment was beneficial for Japanese patients with WHO FC II PAH and treatment should be started in the early stage of the disease.

Progress in solving the sex hormone paradox in pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a devastating and progressive disease with marked morbidity and mortality. Even though being female represents one of the most powerful risk factors for PAH, multiple questions about the underlying mechanisms remain, and two "estrogen paradoxes" in PAH exist. First, it is puzzling why estrogens have been found to be protective in various animal models of PAH, whereas PAH registries uniformly demonstrate a female susceptibility to the disease. Second, despite the pronounced tendency for the disease to develop in women, female PAH patients exhibit better survival than men. Recent mechanistic studies in classical and in novel animal models of PAH, as well as recent studies in PAH patients, have significantly advanced the field. In particular, it is now accepted that estrogen metabolism and receptor signaling, as well as estrogen interactions with key pathways in PAH development, appear to be potent disease modifiers. A better understanding of these interactions may lead to novel PAH therapies. It is the purpose of this review to 1) review sex hormone synthesis, metabolism, and receptor physiology; 2) assess the context in which sex hormones affect PAH pathogenesis; 3) provide a potential explanation for the observed estrogen paradoxes and gender differences in PAH; and 4) identify knowledge gaps and future research opportunities. Because the majority of published studies investigated 17β-estradiol and/or its metabolites, this review will primarily focus on pulmonary vascular and right ventricular effects of estrogens. Data for other sex hormones will be discussed very briefly.

The specialty of pulmonary vascular medicine in China: historical development and future directions

Over the past 40 years, Chinese experts have made great progress on research, diagnosis, and therapy of pulmonary vascular disease, including pulmonary embolism and pulmonary hypertension. These theoretical and clinical advances have increased public awareness about this group of conditions, which are associated with significant morbidity and mortality in China and worldwide. With its theoretical basis combining knowledge from cardiovascular and pulmonary medicine, pulmonary vascular disease has developed into a separate, unique specialty in hospitals across China and worldwide. This article will provide a short historical perspective but also an outlook into the future of this exciting novel discipline. We provide a Chinese perspective, based on our research and clinic experience over the past decades.

Pulmonary hypertension in Portugal: first data from a nationwide registry

Introduction. Pulmonary arterial hypertension (PAH) is a rare disease that must be managed in specialized centers; therefore, the availability of epidemiological national data is critical. Methods. We conducted a prospective, observational, and multicenter registry with a joint collaboration from five centers from Portugal and included adult incident patients with PAH or chronic thromboembolic pulmonary hypertension (CTEPH). Results. Of the 79 patients enrolled in this study, 46 (58.2%) were classified as PAH and 33 patients (41.8%) as CTEPH. PAH patients had a mean age of 43.4 ± 16.4 years. Idiopathic PAH was the most common etiology (37%). At presentation, PAH patients had elevated right atrial pressure (RAP) (7.7 ± 5.9 mmHg) and mean pulmonary vascular resistance (11.4 ± 6.5 Wood units), with a low cardiac index (2.7 ± 1.1 L·min⁻¹·m⁻²); no patient was under selective pulmonary vasodilators; however, at follow-up, most patients were on single (50%), double (28%), or triple (9%) combination vasodilator therapy. One-year survival was 93.5%, similar to CTEPH patients (93.9%), that were older (60.0 ± 12.5 years) and had higher RAP (11.0 ± 5.2 mmHg, P = 0.015). Conclusions. We describe for the first time nationwide data on the diagnosis, management, and prognosis of PAH and CTEPH patients in Portugal. Clinical presentation and outcomes are comparable with those reported on other national registries.

Pulmonary hypertension as an independent predictor of cardiovascular mortality and events in hemodialysis patients

BACKGROUND

Hemodialysis patients are at an increased risk of cardiovascular (CV) morbidity and mortality. Pulmonary hypertension (PH) has been recently reported as a new entity and unrecognized threat in maintenance hemodialysis (MHD) patients, whether PH predicts CV mortality and events in this population remains unknown. The aim of the present study was to determine the value of PH in predicting CV mortality and events in a prospective cohort of MHD patients.

METHODS

We studied 278 MHD patients (98 with and 180 without PH) in Guangdong General Hospital Blood Purification Center, Guangzhou, China. All patients had been followed up for 2 years, and in survival analysis, we considered time to death or first cardiovascular event. The endpoints were all-cause mortality, CV mortality and CV events. PH was defined as systolic pulmonary artery pressure (SPAP) ≥ 35 mmHg as determined by Doppler echocardiographic evaluation.

RESULTS

Of the 278 MHD patients, 53 (19.1 %) died as a result of all causes, 28 (10.1 %) died from CV events (52.8 % of causes of death), and 87 (31.3 %) had new-onset CV events. The survival curve showed that all-cause and CV mortality and new-onset CV events were higher in PH group than the non-PH group. In a multivariate Cox proportional hazard model, the adjusted HR for all-cause mortality, CV mortality and CV events was 1.85 [95 % confidence interval (CI) 1.03-3.34], 2.36 (95 % CI 1.05-5.31) and 2.27 (95 % CI 1.44-3.58), respectively.

CONCLUSIONS

Our study showed that PH was an independent predictor of all-cause mortality and CV mortality and events in MHD patients. We suggest to evaluate SPAP in MHD patients in order to stratify risk of death and CV events.

Pulmonary hypertension in Saudi Arabia: A single center experience

CONTEXT

Several international studies have described the epidemiology of pulmonary hypertension (PH). However, information about the incidence and prevalence of PH in Saudi Arabia is unknown.

AIMS

To report cases of PH and compare the demographic and clinical characteristics of PH due to various causes in a Saudi population.

METHODS

Newly diagnosed cases of PH [defined as mean pulmonary artery pressure >25 mmHg at right heart cauterization (RHC)] were prospectively collected at a single tertiary care hospital from January 2009 and June 2012. Detailed demographic and clinical data were collected at the time of diagnosis, along with hemodynamic parameters.

RESULTS

Of the total 264 patients who underwent RHC, 112 were identified as having PH. The mean age at diagnosis was 55.8 ± 15.8 years, and there was a female preponderance of 72.3%. About 88 (78.6%) of the PH patients were native Saudis and 24 (21.4%) had other origins. Twelve PH patients (10.7%) were classified in group 1 (pulmonary arterial hypertension), 7 (6.2%) in group 2 (PH due to left heart disease), 73 (65.2%) in group 3 (PH due to lung disease), 4 (3.6%) in group 4 (chronic thromboembolic PH), and 16 (14.3%) in group 5 (PH due to multifactorial mechanisms). PH associated with diastolic dysfunction was noted in 28.6% of group 2 patients, 31.5% of group 3 patients, and 25% of group 5 patients.

CONCLUSIONS

These results offer the first report of incident cases of PH across five groups in Saudi Arabia.

Bosentan inhibits oxidative and nitrosative stress and rescues occlusive pulmonary hypertension

Pulmonary arterial hypertension (PH) is a fatal disease marked by excessive pulmonary vascular cell proliferation. Patients with idiopathic PH express endothelin-1 (ET-1) at high levels in their lungs. As the activation of both types of ET-1 receptor (ETA and ETB) leads to increased generation of superoxide and hydrogen peroxide, this may contribute to the severe oxidative stress found in PH patients. As a number of pathways may induce oxidative stress, the particular role of ET-1 remains unclear. The aim of this study was to determine whether inhibition of ET-1 signaling could reduce pulmonary oxidative stress and attenuate the progression of disease in rats with occlusive-angioproliferative PH induced by a single dose of SU5416 (200 mg/kg) and subsequent exposure to hypoxia for 21 days. Using this regimen, animals developed severe PH as evidenced by a progressive increase in right-ventricle (RV) peak systolic pressure (RVPSP), severe RV hypertrophy, and pulmonary endothelial and smooth muscle cell proliferation, resulting in plexiform vasculopathy. PH rats also had increased oxidative stress, correlating with endothelial nitric oxide synthase uncoupling and NADPH oxidase activation, leading to enhanced protein nitration and increases in markers of vascular remodeling. Treatment with the combined ET receptor antagonist bosentan (250 mg/kg/day; day 10 to 21) prevented further increase in RVPSP and RV hypertrophy, decreased ETA/ETB protein levels, reduced oxidative stress and protein nitration, and resulted in marked attenuation of pulmonary vascular cell proliferation. We conclude that inhibition of ET-1 signaling significantly attenuates the oxidative and nitrosative stress associated with PH and prevents its progression.

Efficacy and Safety of Oral Treprostinil Monotherapy for the Treatment of Pulmonary Arterial Hypertension

Background—

Pulmonary arterial hypertension (PAH) is a progressive, fatal disease with no cure. Parenteral and inhaled prostacyclin analogue therapies are effective for the treatment of PAH, but complicated administration requirements can limit the use of these therapies in patients with less severe disease. This study was designed to evaluate the safety and efficacy of the oral prostacyclin analogue treprostinil diolamine as initial treatment for de novo PAH.

Methods and Results—

Three hundred forty-nine patients (intent-to-treat population) not receiving endothelin receptor antagonist or phosphodiesterase type-5 inhibitor background therapy were randomized (treprostinil, n=233; placebo, n=116). The primary analysis population (modified intent-to-treat) included 228 patients (treprostinil, n=151; placebo, n=77) with access to 0.25-mg treprostinil tablets at randomization. The primary end point was change from baseline in 6-minute walk distance at week 12. Secondary end points included Borg dyspnea index, clinical worsening, and symptoms of PAH. The week 12 treatment effect for 6-minute walk distance (modified intent-to-treat population) was 23.0 m ( P =0.0125). For the intent-to-treat population, 6-minute walk distance improvements were observed at peak (26.0 m; P =0.0001) and trough (17.0 m; P =0.0025) plasma study drug concentrations. Other than an improvement in the combined 6-minute walk distance/Borg dyspnea score, there were no significant changes in secondary end points. Oral treprostinil therapy was generally well tolerated; the most common adverse events (intent-to-treat) were headache (69%), nausea (39%), diarrhea (37%), and pain in jaw (25%).

Conclusions—

Oral treprostinil improves exercise capacity in PAH patients not receiving other treatment. Oral treprostinil could provide a convenient, first-line prostacyclin treatment option for PAH patients not requiring more intensive therapy.

Clinical Trial Registration:—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00325403 .

The impact of pulmonary arterial hypertension-targeted therapy on survival in Chinese patients with idiopathic pulmonary arterial hypertension

The survival rates of Chinese patients with idiopathic pulmonary arterial hypertension (IPAH) and familial pulmonary arterial hypertension (PAH) on conventional therapy at 1 and 3 years were 68.0% and 38.9%, respectively. Our aim was to update recent knowledge on the demographics, clinical course, hemodynamic features, disease management, and survival of adult patients with IPAH. This retrospective and observational study was conducted at the largest tertiary referral center in China. Ninety patients with IPAH who underwent initial evaluation at Fu Wai Hospital from January 2006 through November 2009 were retrospectively enrolled. The primary outcome was death. Statistical analyses used included independent sample t test, nonparametric test, Kaplan-Meier method, and Cox proportional hazards analysis. Of the 90 patients enrolled, the median age was 32 years with female predominance. The median interval from onset of symptoms to diagnosis was 14 months. Patients exhibited severe exercise limitation and hemodynamic abnormalities at diagnosis. Only 10.6% had a positive vasoreactivity test, while calcium channel blockers were given to 22.2% of patients. Fifty-nine patients (65.6%) received PAH-targeted therapies during follow-up. Our survival rates of 84.1%, 73.7%, and 70.6% at 1-, 2-, and 3-years compared favorably with predicted survival based on the National Institutes of Health equation which showed 1-, 2-, and 3-years survival rates of 67.7%, 55.9%, and 47%, respectively. For the patients receiving conventional therapy solely, the 1- and 3-years survival rates were 67.0% and 49.3%, respectively. Younger age, lower body mass index, presence of pericardial effusion, and absence of PAH-targeted therapy were independently associated with mortality. We concluded that patients with IPAH were still diagnosed too late, and while survival rates have improved in the modern treatment era, there is still room for improvement.

Elderly patients diagnosed with idiopathic pulmonary arterial hypertension: results from the COMPERA registry

BACKGROUND

Originally reported to occur predominantly in younger women, idiopathic pulmonary arterial hypertension (IPAH) is increasingly diagnosed in elderly patients. We aimed to describe the characteristics of such patients and their survival under clinical practice conditions.

METHODS

Prospective registry in 28 centers in 6 European countries. Demographics, clinical characteristics, hemodynamics, treatment patterns and outcomes of younger (18-65 years) and elderly (>65 years) patients with newly diagnosed IPAH (incident cases only) were compared.

RESULTS

A total of 587 patients were eligible for analysis. The median (interquartile, [IQR]) age at diagnosis was 71 (16) years. Younger patients (n=209; median age, 54 [16] years) showed a female-to-male ratio of 2.3:1 whereas the gender ratio in elderly patients (n=378; median age, 75 [8] years) was almost even (1.2:1). Combinations of PAH drugs were widely used in both populations, albeit less frequently in older patients. Elderly patients were less likely to reach current treatment targets (6 min walking distance>400 m, functional class I or II). The survival rates 1, 2, and 3 years after the diagnosis of IPAH were lower in elderly patients, even when adjusted for age- and gender-matched survival tables of the general population (p=0.006 by log-rank analysis).

CONCLUSIONS

In countries with an aging population, IPAH is now frequently diagnosed in elderly patients. Compared to younger patients, elderly patients present with a balanced gender ratio and different clinical features, respond less well to medical therapy and have a higher age-adjusted mortality. Further characterization of these patients is required.

CLINICAL TRIALS REGISTRATION

NCT01347216.

Pulmonary hypertension associated with rheumatic diseases: baseline characteristics from the Korean registry

OBJECTIVES

The REgistry of Pulmonary Hypertension Associated with Rheumatic Disease (REOPARD) was established in Korea. The baseline data are described from the second year of the registry's operation.

METHODS

Patients with a connective tissue disease (CTD) who met the modified definition of the WHO group I pulmonary arterial hypertension (PAH) were enrolled. PAH was defined as a systolic pulmonary arterial pressure> 40 mmHg by echocardiography or mean pulmonary arterial pressure> 25 mmHg by right heart catheterization. Hemodynamic parameters and clinical data such as demographics, functional class, underlying disease, organ involvement, laboratory tests and current treatment were recorded.

RESULTS

A total of 321 patients were enrolled during the 2-year study period from 2008 to 2010. The mean age of the patients at registration was 51.9 years and 87.5% were female. Most patients were diagnosed by echocardiography and only 24 patients (7.5%) underwent cardiac catheterization. Exertional dyspnea was present in 63.6% of patients and 31.8% were New York Heart Association class III or IV. Among the patients, systemic lupus erythematosus accounted for 35.3%, systemic sclerosis 28.3%, rheumatoid arthritis 7.8%, overlap syndrome 9.0%, and mixed connective tissue disease 5.9%. There were no significant differences in hemodynamics, functional class, diffusing capacity and N-terminal pro-brain natriuretic peptide levels between the disease subgroups. Treatments consisted of calcium antagonists (57.0%), endothelin antagonists (32.7%), prostanoids (27.1%), phosphodiesterase-5 inhibitors (14.3%) and combinations (37.4%).

CONCLUSION

Compared with previous studies, the results showed some differences: underlying diseases, functional status and treatments. This may be due to differences in ethnic background and diagnostic methods of our study.

Nicorandil prevents right ventricular remodeling by inhibiting apoptosis and lowering pressure overload in rats with pulmonary arterial hypertension

Background

Most of the deaths among patients with severe pulmonary arterial hypertension (PAH) are caused by progressive right ventricular (RV) pathological remodeling, dysfunction, and failure. Nicorandil can inhibit the development of PAH by reducing pulmonary artery pressure and RV hypertrophy. However, whether nicorandil can inhibit apoptosis in RV cardiomyocytes and prevent RV remodeling has been unclear.

Methodology/Principal Findings

RV remodeling was induced in rats by intraperitoneal injection of monocrotaline (MCT). RV systolic pressure (RVSP) was measured at the end of each week after MCT injection. Blood samples were drawn for brain natriuretic peptide (BNP) ELISA analysis. The hearts were excised for histopathological, ultrastructural, immunohistochemical, and Western blotting analyses. The MCT-injected rats exhibited greater mortality and less weight gain and showed significantly increased RVSP and RV hypertrophy during the second week. These worsened during the third week. MCT injection for three weeks caused pathological RV remodeling, characterized by hypertrophy, fibrosis, dysfunction, and RV mitochondrial impairment, as indicated by increased levels of apoptosis. Nicorandil improved survival, weight gain, and RV function, ameliorated RV pressure overload, and prevented maladaptive RV remodeling in PAH rats. Nicorandil also reduced the number of apoptotic cardiomyocytes, with a concomitant increase in Bcl-2/Bax ratio. 5-hydroxydecanoate (5-HD) reversed these beneficial effects of nicorandil in MCT-injected rats.

Conclusions/Significance

Nicorandil inhibits PAH-induced RV remodeling in rats not only by reducing RV pressure overload but also by inhibiting apoptosis in cardiomyocytes through the activation of mitochondrial ATP-sensitive K⁺ (mitoK_ATP) channels. The use of a mitoK_ATP channel opener such as nicorandil for PAH-associated RV remodeling and dysfunction may represent a new therapeutic strategy for the amelioration of RV remodeling during the early stages of PAH.

Macrophage migration inhibitory factor mediates hypoxia-induced pulmonary hypertension

Pulmonary hypertension (PH) is a devastating disease leading to progressive hypoxemia, right ventricular failure, and death. Hypoxia can play a pivotal role in PH etiology, inducing pulmonary vessel constriction and remodeling. These events lead to increased pulmonary vessel wall thickness, elevated vascular resistance and right ventricular hypertrophy. The current study examined the association of the inflammatory cytokine macrophage migration inhibitory factor (MIF) with chronic lung disease and its role in the development of hypoxia-induced PH. We found that plasma MIF in patients with primary PH or PH secondary to interstitial lung disease (ILD) was significantly higher than in the control group (P = 0.004 and 0.007, respectively). MIF involvement with hypoxia-induced fibroblast proliferation was examined in both a human cell-line and primary mouse cells from wild-type (mif⁺/⁺) and MIF-knockout (mif⁻/⁻) mice. In vitro, hypoxia-increased MIF mRNA, extracellular MIF protein accumulation and cell proliferation. Inhibition of MIF inflammatory activity reduced hypoxia-induced cell proliferation. However, hypoxia only increased proliferation of mif⁻/⁻ cells when they were supplemented with media from mif⁺/⁺ cells. This growth increase was suppressed by MIF inhibition. In vivo, chronic exposure of mice to a normobaric atmosphere of 10% oxygen increased lung tissue expression of mRNA encoding MIF and accumulation of MIF in plasma. Inhibition of the MIF inflammatory active site, during hypoxic exposure, significantly reduced pulmonary vascular remodeling, cardiac hypertrophy and right ventricular systolic pressure. The data suggest that MIF plays a critical role in hypoxia-induced PH, and its inhibition may be beneficial in preventing the development and progression of the disease.

Pediatric Pulmonary Hypertension in the Netherlands

Background—

Incidence and prevalence rates for pediatric pulmonary hypertension (PH) and pulmonary arterial hypertension (PAH) are unknown. This study describes the nationwide epidemiological features of pediatric PH in the Netherlands during a 15-year period and the clinical course of pediatric PAH.

Methods and Results—

Two registries were used to retrospectively identify children (0–17 years) with PH. Overall, 3263 pediatric patients were identified with PH due to left heart disease (n=160; 5%), lung disease/hypoxemia (n=253; 8%), thromboembolic disease (n=5; <1%), and transient (n=2691; 82%) and progressive (n=154; 5%) PAH. Transient PAH included persistent PH of the newborn and children with congenital heart defects (CHD) and systemic-to-pulmonary shunt, in whom PAH resolved after successful shunt correction. Progressive PAH mainly included idiopathic PAH (n=36; iPAH) and PAH associated with CHD (n=111; PAH-CHD). Pulmonary arterial hypertension associated with CHD represented highly heterogeneous subgroups. Syndromes were frequently present, especially in progressive PAH (n=60; 39%). Survival for PAH-CHD varied depending on the subgroups, some showing better and others showing worse survival than for iPAH. Survival of children with Eisenmenger syndrome appeared worse than reported in adults. For iPAH and PAH-CHD, annual incidence and point prevalence averaged, respectively, 0.7 and 4.4 (iPAH) and 2.2 and 15.6 (PAH-CHD) cases per million children. Compared to studies in adults, iPAH occurred less whereas PAH-CHD occurred more frequently.

Conclusions—

Pediatric PH is characterized by various age-specific diagnoses, the majority of which comprise transient forms of PAH. Incidence of pediatric iPAH is lower whereas incidence of pediatric PAH-CHD is higher than reported in adults. Pediatric PAH-CHD represents a heterogeneous group with highly variable clinical courses.

Impact of sildenafil on survival of patients with idiopathic pulmonary arterial hypertension

It has been reported that short-term sildenafil therapy is safe and effective for patients with pulmonary arterial hypertension. However, data regarding the impact of sildenafil on the survival of patients with idiopathic pulmonary arterial hypertension remain limited. The study was conducted on 77 patients with newly diagnosed idiopathic pulmonary arterial hypertension at Fu Wai Hospital between September 2005 and September 2009. Patients were divided into 2 groups: the sildenafil group and the conventional group. Nine patients treated with sildenafil were re-evaluated by right heart catheterization after 3 months. Our data demonstrated that the 6-minute walk distance, World Health Organization functional class, mixed venous oxygen saturation, and hemodynamics significantly improved after 3 months of sildenafil therapy (P < .05). The baseline characteristics of the sildenafil group were similar to those of the conventional group. The 1-, 2-, and 3-year survival rates in the sildenafil group were 88%, 72%, and 68% compared with 61%, 36%, and 27% in the conventional group (P < .001). The absence of sildenafil therapy, lower body mass index, and lower mixed venous oxygen saturation were found to be independent predictors of mortality. In conclusion, sildenafil therapy was found to be associated with improved survival in patients with idiopathic pulmonary arterial hypertension.

Cardiopulmonary exercise testing in the assessment of pulmonary hypertension

The assessment of patients with suspected or confirmed pulmonary arterial hypertension (PAH) and secondary pulmonary hypertension (PH) continues to evolve and, in recent years, evidence demonstrating that cardiopulmonary exercise testing (CPX) provides valuable information has grown at an impressive rate. The key premise supporting the use of CPX is that certain variables obtained provide insight into the degree of ventilation/perfusion mismatching secondary to altered pulmonary hemodynamics. In this article, we discuss the pathophysiology of PAH and secondary PH and its impact on cardiac function, review the clinical presentation of patients with elevated pulmonary pressures and outline a case for the use of CPX as an integral assessment technique, discuss CPX technology and testing procedures, and review the current state of available evidence and provide clinical recommendations for CPX in the setting of known or suspected PAH and secondary PH.

Sex differences in the diagnosis, treatment, and outcome of patients with pulmonary arterial hypertension enrolled in the registry to evaluate early and long-term pulmonary arterial hypertension disease management

BACKGROUND

Pulmonary arterial hypertension (PAH) is a life-threatening disease that affects more women than men. The reasons for the female preponderance are unclear, and there are limited data available for men with PAH.

METHODS

Data from the Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL Registry) were analyzed to explore sex differences among patients with PAH with regard to 2-year survival from enrollment and 5-year survival from time of diagnosis.

RESULTS

The data set included 2,318 women and 651 men. More women had PAH associated with connective tissue disease (P < .001), and more men had portopulmonary hypertension (P < .001) and HIV-associated PAH (P < .001). More women had congenital heart disease-associated PAH (P = .017), thyroid disease (P < .001), and depression reported (P ≤ .001). At diagnosis, men had higher mean pulmonary artery pressure (53 ± 14 vs 51 ± 14.3 mm Hg; P = .013) and mean right atrial pressure (10 ± 6 vs 9 ± 6 mm Hg; P = .031). Women had better survival estimates for 2 years from enrollment and for 5 years from diagnosis. Stratifying by age showed that survival from enrollment was similar between men and women aged < 60 years at enrollment, whereas men aged ≥ 60 years have lower survival rates compared with women aged ≥ 60 years.

CONCLUSIONS

Our findings highlight similarities and differences between men and women with PAH, raising questions for future exploration regarding the role of hormones and sex in causation and survival in PAH.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT00370214; URL: www.clinicaltrials.gov.

Delay in recognition of pulmonary arterial hypertension: factors identified from the REVEAL Registry

BACKGROUND

Pulmonary arterial hypertension (PAH) is a progressive and fatal disorder. Despite the emergence of effective therapy, PAH is commonly at an advanced stage when recognized. Factors associated with a prolonged symptomatic period before the recognition of PAH have not been fully evaluated.

METHODS

The Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL Registry) enrolled 2,967 US adult patients with PAH from March 2006 to September 2007. Patients were considered to have delayed disease recognition if > 2 years elapsed between symptom onset and the patient receiving a PAH diagnosis, starting on PAH-specific therapy, or receiving a diagnosis by right-sided heart catheterization.

RESULTS

In 21.1% of patients, symptoms were experienced for > 2 years before PAH was recognized. Patients with onset of PAH symptoms before age 36 years showed the highest likelihood of delayed disease recognition (OR, 3.07; 95% CI, 2.03-4.66). History of obstructive airways disease (OR, 1.93; 95% CI, 1.5-2.47) and sleep apnea (OR, 1.72; 95% CI, 1.33-2.22) were independently associated with delayed PAH recognition. Six-minute walk distance < 250 m (OR, 1.91; 95% CI, 1.16-3.13), right atrial pressure < 10 mm Hg (OR, 1.77; 95% CI, 1.26-2.48), and pulmonary vascular resistance < 10 Wood units (OR, 1.28; 95% CI, 1.02-1.60) were also associated with delayed disease recognition, but sex, race/ethnicity, and geographic region showed no association.

CONCLUSIONS

One in five patients in the REVEAL Registry who were diagnosed with PAH reported symptoms for > 2 years before their disease was recognized. Younger individuals and patients with histories of common respiratory disorders were most likely to experience delayed PAH recognition.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT00370214; URL: www.clinicaltrials.gov.

Survival of Chinese patients with pulmonary arterial hypertension in the modern treatment era

BACKGROUND

In a previous study of Chinese patients with idiopathic pulmonary arterial hypertension (IPAH) in the nontargeted therapy era (defined as the time before 2006 when new pulmonary arterial hypertension-specific drugs were not available in China), we reported 1- and 3-year survival estimates of only 68% and 39%, respectively. However, it is not yet known whether the survival of patients with pulmonary arterial hypertension is improved in the modern treatment era (defined in China as after 2006).

METHODS

A retrospective cohort study was undertaken in 276 consecutive patients with newly diagnosed incident IPAH and connective tissue disease-related pulmonary arterial hypertension (CTDPAH) who were referred between 2007 and 2009. Baseline characteristics and survival rates in the two groups were compared.

RESULTS

The 1- and 3-year survival estimates were 92.1% and 75.1%, respectively, in patients with IPAH, and 85.4% and 53.6%, respectively, in patients with CTDPAH. Patients with CTDPAH had a significantly lower mean pulmonary artery pressure, more pericardial effusion, and more severe impairment of the diffusion capacity of the lung for carbon monoxide than patients with IPAH. A diagnosis of CTDPAH, World Health Organization functional class III or IV, single-breath diffusion capacity of the lung for carbon monoxide < 80% predicted, and the presence of pericardial effusion were independent predictors of mortality. The 1- and 3-year survival rates of male patients were 93.5% and 77.5%, respectively, in those with IPAH, and 71.1% and 47.4%, respectively, in those with CTDPAH.

CONCLUSIONS

The survival rates of patients with pulmonary arterial hypertension have improved in China in the modern treatment era, despite the high costs of treatment and financial constraints. However, the survival rates of patients with CTDPAH are inferior to those of patients with IPAH. Our study also indicates poorer survival rates in male patients with CTDPAH.

Estrogens and development of pulmonary hypertension: interaction of estradiol metabolism and pulmonary vascular disease

Severe pulmonary arterial hypertension (PAH) is characterized by clustered proliferation of endothelial cells (ECs) in the lumina of small size pulmonary arteries resulting in concentric obliteration of the lumina and formation of complex vascular structures known as plexiform lesions. This debilitating disease occurs more frequently in women, yet both animal studies in classical models of PAH and limited clinical data suggest protective effects of estrogens: the estrogen paradox in pulmonary hypertension. Little is known about the role of estrogens in PAH, but one line of evidence strongly suggests that the vascular protective effects of 17β-estradiol (estradiol; E2) are mediated largely by its downstream metabolites. Estradiol is metabolized to 2-hydroxyestradiol (2HE) by CYP1A1/CYP1B1, and 2HE is converted to 2-methoxyestradiol (2ME) by catechol-O-methyl transferase. 2ME is extensively metabolized to 2-methoxyestrone, a metabolite that lacks biologic activity, but which may be converted back to 2ME. 2ME has no estrogenic activity, and its effects are mediated by estrogen receptors–independent mechanism(s). Notably, in systemic and pulmonary vascular ECs, smooth muscle cells, and fibroblasts, 2ME exerts stronger antimitotic effects than E2 itself. E2 and 2ME, despite having similar effects on other cardiovascular cells, have opposing effects on ECs; that is, in ECs, E2 is promitogenic, proangiogenic, and antiapoptotic, whereas 2ME is antimitogenic, antiangiogenic, and proapoptotic. This may have significant ramifications in severe PAH that involves uncontrolled proliferation of monoclonal apoptosis-resistant ECs. Based on its cellular effects, 2ME should be expected to attenuate the progression of disease and provide protection in severe PAH. In contrast, E2, due to its mitogenic, angiogenic, and antiapoptotic effects (otherwise desirable in normal quiescent ECs), may even adversely affect endothelial remodeling in PAH, and this may be even more significant if the E2's effects on injured endothelium are not opposed by 2ME (eg, in the event of reduced E2 conversion to 2ME due to hypoxia, inflammation, drugs, environmental factors, or genetic polymorphism of metabolizing enzymes). This review focuses on the effects of estrogens and their metabolites on pulmonary vascular pathobiology and the development of experimental PAH and offers potential explanation for the estrogen paradox in PAH. Furthermore, we propose that unbalanced estradiol metabolism may lead to the development of PAH. Recent animal data and studies in patients with PAH support this concept.

Assessment of pulmonary hypertension in the pediatric catheterization laboratory: current insights from the Magic registry

OBJECTIVES

To assess protocols, demographics, and hemodynamics in pediatric patients undergoing catheterization for pulmonary hypertension (PH).

BACKGROUND

Pediatric specific data is limited on PH.

METHODS

Review of the Mid-Atlantic Group of Interventional Cardiology (MAGIC) collaboration PH registry dataset.

RESULTS

Between November 2003 and October 2008, seven institutions submitted data from 177 initial catheterizations in pediatric patients with suspected PH. Pulmonary arterial hypertension associated with congenital heart disease (APAH-CHD) (n = 61, 34%) was more common than idiopathic PAH (IPAH) (n = 36, 20%). IPAH patients were older with higher mean pulmonary arterial pressures (mPAP) (P < 0.01). Oxygen lowered mPAP in patients with IPAH (P < 0.01) and associated PAH not related to congenital heart disease (APAH-non CHD) (P < 0.01). A synergistic effect was seen with inhaled nitric oxide (iNO) (P < 0.01). Overall 9/30 (29%) patients with IPAH and 8/48 (16%) patients with APAH-non CHD were reactive to vasodilator testing. Oxygen lowered pulmonary vascular resistance index (PVRI) in patients with APAH-CHD (P < 0.01). There was no additive effect with iNO but a subset of patients required iNO to lower PVRI below 5 WU·m(2). General anesthesia (GA) lowered systemic arterial pressure (P < 0.01) with no difference between GA and procedural sedation on mPAP or PVRI. Adverse events were rare (n = 7) with no procedural deaths.

CONCLUSIONS

Pediatric patients with PH demonstrate a higher incidence of APAH-CHD and neonatal specific disorders compared to adults. Pediatric PH patients may demonstrate baseline mPAP < 40 mm Hg but > 50% systemic illustrating the difficulty in applying adult criteria to children with PH. Catheterization in children with PH is relatively safe.

Integration of clinical and hemodynamic parameters in the prediction of long-term survival in patients with pulmonary arterial hypertension

BACKGROUND

Current management guidelines for pulmonary arterial hypertension (PAH) recommend a treatment choice based primarily on World Health Organization (WHO) functional class. This study was designed to assess how the incorporation of readily obtained clinical and test-based information may significantly improve the prediction of outcomes over functional class alone.

METHODS

Clinical and hemodynamic variables were assessed in 484 consecutive patients presenting with WHO group 1 PAH. The primary outcome measure was time to all-cause mortality over 5 years from the index presentation (data available in all). Follow-up was censored at the time of lung or heart/lung transplant in 21 patients or at 5 years. Predictors of mortality were assessed sequentially using Cox models, with the step-wise incorporation of clinical variables, echocardiographic, and catheterization findings. Results were further compared with the REVEAL (Registry to Evaluate Early and Long-term Pulmonary Arterial Hypertension Disease Management) prediction score.

RESULTS

Overall median survival was 237 weeks (95% CI, 196-266), corresponding to 1-year, 3-year, and 5-year survival rates of 81.1% (77.0, 84.7), 61.1% (56.5, 65.3), and 47.9% (43.2, 52.4), respectively. The prediction of mortality was improved incrementally by incorporating clinical and echocardiographic measures with a concordance index (c-index) of 0.84 compared with that of 0.60 with functional class alone. The REVEAL prediction score was validated independently in this cohort to predict both 1-year and 5-year mortality. It had a prediction c-index of 0.71.

CONCLUSIONS

The integration of routine PAH clinical (predominantly noninvasive) parameters predicts long-term outcome better than functional class and, hence, should be incorporated into medical management decisions.