ABSTRACT
Rationale: The lung allocation score (LAS) was revised in 2015 to improve waiting list mortality and rate of transplant for patients with pulmonary arterial hypertension (PAH). Objectives: We sought to determine if the 2015 revision achieved its intended goals. Methods: Using the Standard Transplant Analysis and Research file, we assessed the impact of the 2015 LAS revision by comparing the pre- and postrevision eras. Registrants were divided into the LAS diagnostic categories: group A-chronic obstructive pulmonary disease; group B-pulmonary arterial hypertension; group C-cystic fibrosis; and group D-interstitial lung disease. Competing risk regressions were used to assess the two mutually exclusive competing risks of waiting list death and transplant. Cumulative incidence plots were created to visually inspect risks. Measurements and Main Results: The LAS at organ matching increased by 14.2 points for registrants with PAH after the 2015 LAS revision, the greatest increase among diagnostic categories (other LAS categories: Δ, -0.9 to +2.8 points). Before the revision, registrants with PAH had the highest risk of death and lowest likelihood of transplant. After the 2015 revision, registrants with PAH still had the highest risk of death, now similar to those with interstitial lung disease, and the lowest rate of transplant, now similar to those with chronic obstructive pulmonary disease. Conclusions: Although the 2015 LAS revision improved access to transplant and reduced the risk of waitlist death for patients with PAH, it did not go far enough. Significant differences in waitlist mortality and likelihood of transplant persist.
Subject(s)
Cystic Fibrosis , Lung Transplantation , Pulmonary Arterial Hypertension , Pulmonary Disease, Chronic Obstructive , Tissue and Organ Procurement , Humans , Pulmonary Arterial Hypertension/surgery , Pulmonary Disease, Chronic Obstructive/surgery , Familial Primary Pulmonary Hypertension , Waiting Lists , Lung , Retrospective StudiesABSTRACT
PURPOSE OF REVIEW: Methamphetamine use is increasing in popularity globally, and chronic users suffer from various drug toxicities, including the development of pulmonary arterial hypertension. Although it was previously thought to be a possible cause of pulmonary arterial hypertension, as of the sixth World Symposium on Pulmonary Hypertension, methamphetamine use is now recognized as a definite cause of pulmonary arterial hypertension. This review will discuss the history of methamphetamine use, the link between methamphetamine use and pulmonary arterial hypertension, and the clinical characteristics of patients with pulmonary hypertension from methamphetamine use. RECENT FINDINGS: The mechanism by which methamphetamine abuse leads to pulmonary hypertension is unclear. However, recent studies have suggested that reduced expression of carboxylesterase 1 may be implicated due to maladaptation to the environmental injury of methamphetamine abuse. Based on the report of two recent cohort studies, patients with methamphetamine-associated pulmonary arterial hypertension have a worse functional class, less favorable hemodynamics, impaired health-related quality of life, increased health-care utilization, and attenuated survival, as compared to those with idiopathic pulmonary arterial hypertension. SUMMARY: Future studies are needed to better understand the mechanism by which methamphetamine use leads to pulmonary arterial hypertension. Methamphetamine-associated pulmonary arterial hypertension likely represents a more advanced disease state than idiopathic pulmonary arterial hypertension, however, it is treated less aggressively in clinical practice.
Subject(s)
Amphetamine-Related Disorders , Hypertension, Pulmonary , Methamphetamine , Pulmonary Arterial Hypertension , Amphetamine-Related Disorders/complications , Familial Primary Pulmonary Hypertension , Humans , Hypertension, Pulmonary/etiology , Methamphetamine/toxicity , Quality of LifeABSTRACT
BACKGROUND: The effect of secondhand tobacco smoke (SHS) exposure on patients with heart failure (HF) is uncertain. We investigated the association of mortality with SHS exposure for patients with HF. METHODS: Nonsmokers with clinical HF were enrolled from 2003 to 2008 in a single-center longitudinal cohort study. The effect of SHS exposure determined by high-sensitivity urinary cotinine on mortality was estimated by multivariable proportional hazards modeling. RESULTS: Mortality was assessed after median 4.3 years. Of 202 patients, enrollment urinary cotinine levels were below the limit of detection for 106 (52%) considered unexposed to SHS. The median detectable cotinine was 0.47 ng/mL (interquartile range: [0.28, 1.28]). Participants were 41% female, 65 ± 17 years old, and 57% white race. Elevated cotinine was associated with increased mortality after multivariate adjustment: hazard ratio (HR) per 1 ng/mL increase in urinary cotinine: 1.15, 95% confidence interval (CI): 1.08-1.23, P < .001. Higher age (HR per 5-year increase: 1.32, 95% CI: 1.22-1.43, P < .001), male sex (HR vs female: 1.52, 95% CI: 1.02-2.28, P = .040), and New York Heart Association class (HR for class III vs I: 2.91, 95% CI: 1.71-4.99, P < .001) were also associated with mortality. CONCLUSIONS: SHS exposure is associated with a dose-dependent increase in mortality for patients with HF.
Subject(s)
Heart Failure , Tobacco Smoke Pollution , Aged , Aged, 80 and over , Cohort Studies , Cotinine/analysis , Female , Heart Failure/mortality , Humans , Longitudinal Studies , Male , Middle Aged , Tobacco Smoke Pollution/statistics & numerical dataABSTRACT
BACKGROUND: To estimate oxygen uptake (VO2) from cardiopulmonary exercise testing (CPX) using simultaneously recorded seismocardiogram (SCG) and electrocardiogram (ECG) signals captured with a small wearable patch. CPX is an important risk stratification tool for patients with heart failure (HF) owing to the prognostic value of the features derived from the gas exchange variables such as VO2. However, CPX requires specialized equipment, as well as trained professionals to conduct the study. METHODS AND RESULTS: We have conducted a total of 68 CPX tests on 59 patients with HF with reduced ejection fraction (31% women, mean age 55 ± 13 years, ejection fraction 0.27 ± 0.11, 79% stage C). The patients were fitted with a wearable sensing patch and underwent treadmill CPX. We divided the dataset into a training-testing set (nâ¯=â¯44) and a separate validation set (nâ¯=â¯24). We developed globalized (population) regression models to estimate VO2 from the SCG and ECG signals measured continuously with the patch. We further classified the patients as stage D or C using the SCG and ECG features to assess the ability to detect clinical state from the wearable patch measurements alone. We developed the regression and classification model with cross-validation on the training-testing set and validated the models on the validation set. The regression model to estimate VO2 from the wearable features yielded a moderate correlation (R2 of 0.64) with a root mean square error of 2.51 ± 1.12 mL · kg-1 · min-1 on the training-testing set, whereas R2 and root mean square error on the validation set were 0.76 and 2.28 ± 0.93 mL · kg-1 · min-1, respectively. Furthermore, the classification of clinical state yielded accuracy, sensitivity, specificity, and an area under the receiver operating characteristic curve values of 0.84, 0.91, 0.64, and 0.74, respectively, for the training-testing set, and 0.83, 0.86, 0.67, and 0.92, respectively, for the validation set. CONCLUSIONS: Wearable SCG and ECG can assess CPX VO2 and thereby classify clinical status for patients with HF. These methods may provide value in the risk stratification of patients with HF by tracking cardiopulmonary parameters and clinical status outside of specialized settings, potentially allowing for more frequent assessments to be performed during longitudinal monitoring and treatment.
Subject(s)
Heart Failure , Wearable Electronic Devices , Exercise Test , Female , Heart Failure/diagnosis , Humans , Male , Middle Aged , Oxygen , Oxygen Consumption , Stroke VolumeABSTRACT
BACKGROUND: While lung transplantation (LTx) has been effective for connective tissue disease (CTD) patients with pulmonary involvement, outcomes for heart-lung transplantation (HLTx) are less defined. The aim of this study is to evaluate HLTx in CTD patients utilizing the UNOS database. METHODS: HLTx patients with CTD (HLTx-CTD) were compared to both LTx patients with CTD (LTx-CTD) and HLTx patients with all other indications (HLTx-OI) from 1999 to 2018. Primary outcome was 1- and 5-year graft survival. Secondary outcomes included freedom from first-year rejection and outcomes prior to transplant discharge. RESULTS: 1143/29 323 adults received first-time HLTx or LTx for CTD. Seventeen were HLTx-CTD (3.3% of total HLTx) and 1126 were LTx-CTD (3.9% of total LTx). There were 492 HLTx-OI. Transplant hemodynamic values including cardiac output, pulmonary capillary wedge pressure, and calculated pulmonary vascular resistance were significantly worse for HLTx-CTD vs LTx-CTD (4.2 vs 5.4 L/min, P = .005; 14 vs 10 mm Hg, P = .009; 439 vs 267 dynes, P = .007, respectively). Cardiac status 1 was more common for HLTx-CTD vs HLTx-OI (94% vs 56%, P < .001). HLTx-CTD 1 and 5-year graft survival was similar compared to LTx-CTD and HLTx-OI. CONCLUSION: HLTx-CTD is a valid option for carefully selected patients with CTD cardiac and pulmonary involvement with similar morbidity and mortality compared to LTx-CTD and HLTx-OI.
Subject(s)
Connective Tissue Diseases , Heart-Lung Transplantation , Lung Transplantation , Adult , Connective Tissue Diseases/surgery , Databases, Factual , Graft Survival , HumansSubject(s)
Arginine , Hypertension, Pulmonary , Humans , Arginine/pharmacokinetics , Biological AvailabilityABSTRACT
Clinical Trials in Organ Transplantation-18 (CTOT-18) is a follow-up analysis of the 200-subject multicenter heart transplant CTOT-05 cohort. CTOT-18 aimed to identify clinical, epidemiologic, and biologic markers associated with adverse clinical events past 1 year posttransplantation. We examined various candidate biomarkers including serum antibodies, angiogenic proteins, blood gene expression profiles, and T cell alloreactivity. The composite endpoint (CE) included death, retransplantation, coronary stent, myocardial infarction, and cardiac allograft vasculopathy. The mean follow-up was 4.5 ± SD 1.1 years. Subjects with serum anti-cardiac myosin (CM) antibody detected at transplantation and at 12 months had a higher risk of meeting the CE compared to those without anti-CM antibody (hazard ratio [HR] = 2.9, P = .046). Plasma VEGF-A and VEGF-C levels pretransplant were associated with CE (odds ratio [OR] = 13.24, P = .029; and OR = 0.13, P = .037, respectively). Early intravascular ultrasound findings or other candidate biomarkers were not associated with the study outcomes. In conclusion, anti-CM antibody and plasma levels of VEGF-A and VEGF-C were associated with an increased risk of adverse events. Although this multicenter report supports further evaluation of the mechanisms through which anti-CM antibody and plasma angiogenesis proteins lead to allograft injury, we could not identify additional markers of adverse events or potential novel therapeutic targets.
Subject(s)
Biomarkers/metabolism , Heart Failure/metabolism , Heart Failure/surgery , Heart Transplantation , Adult , Enzyme-Linked Immunosorbent Assay , Female , Follow-Up Studies , Gene Expression Profiling , HLA Antigens/immunology , Humans , Immune System , Male , Middle Aged , Myosins/immunology , Neovascularization, Pathologic , Proportional Hazards Models , Prospective Studies , Retrospective Studies , Risk , T-Lymphocytes/immunology , Treatment Outcome , Vascular Endothelial Growth Factor A/blood , Vascular Endothelial Growth Factor C/blood , Vimentin/immunologyABSTRACT
Pulmonary hypertension (PH) is frequent in left heart disease (LHD), as a consequence of the underlying condition. Significant advances have occurred over the past 5â years since the 5th World Symposium on Pulmonary Hypertension in 2013, leading to a better understanding of PH-LHD, challenges and gaps in evidence. PH in heart failure with preserved ejection fraction represents the most complex situation, as it may be misdiagnosed with group 1 PH. Based on the latest evidence, we propose a new haemodynamic definition for PH due to LHD and a three-step pragmatic approach to differential diagnosis. This includes the identification of a specific "left heart" phenotype and a non-invasive probability of PH-LHD. Invasive confirmation of PH-LHD is based on the accurate measurement of pulmonary arterial wedge pressure and, in patients with high probability, provocative testing to clarify the diagnosis. Finally, recent clinical trials did not demonstrate a benefit in treating PH due to LHD with pulmonary arterial hypertension-approved therapies.
Subject(s)
Hypertension, Pulmonary/diagnosis , Hypertension, Pulmonary/epidemiology , Ventricular Dysfunction, Left/diagnosis , Ventricular Dysfunction, Left/epidemiology , Humans , Hypertension, Pulmonary/therapy , Pulmonary Wedge Pressure , Randomized Controlled Trials as Topic , Vascular Resistance , Ventricular Dysfunction, Left/therapyABSTRACT
Despite limitations in sensitivity and specificity, estimation of the pulmonary artery systolic pressure (ePASP) on echocardiography is used for portopulmonary hypertension (PoPH) screening in liver transplant (LT) candidates. We proposed that alternative echocardiographic models, such as estimated pulmonary vascular resistance (ePVR), may provide improved testing characteristics in PoPH screening. In a retrospective analysis of 100 LT candidates, we found that the formula ePVR = ePASP/VTIRVOT + 3 if MSN (VTIRVOT = right ventricular outflow tract time velocity integral; MSN = mid-systolic notching of the VTIRVOT Doppler signal) significantly improves accuracy of PoPH screening compared to ePASP. We determined the optimal ePVR cutoff for PoPH screening to be 2.76 Wood units, as this cutoff provided 100% sensitivity and 73% specificity in screening for clinically significant PoPH. Comparatively, ePASP at a cutoff of 40 mm Hg provided 91% sensitivity and 48% specificity. We devised a new screening algorithm based on the use of ePVR at intermediate ePASP values (35-54 mm Hg), and we confirmed the testing characteristics of this algorithm in a separate validation cohort of 50 LT candidates. In screening LT candidates for PoPH, the ePASP lacks accuracy, leading to unnecessary RHCs and undiagnosed cases of PoPH. A screening algorithm which incorporates the ePVR may be more reliable.
Subject(s)
Hypertension, Portal/diagnosis , Hypertension, Pulmonary/diagnosis , Liver Transplantation/statistics & numerical data , Ultrasonography, Doppler/methods , Vascular Resistance , Cardiac Catheterization/methods , Echocardiography/methods , Female , Follow-Up Studies , Humans , Hypertension, Portal/diagnostic imaging , Hypertension, Pulmonary/diagnostic imaging , Male , Middle Aged , Prognosis , ROC Curve , Retrospective StudiesABSTRACT
PURPOSE OF REVIEW: Pulmonary hypertension (PH) frequently complicates heart failure and portends a worse prognosis. This review will summarize and discuss recent updates in the classification and management of patients with PH due to left heart disease. RECENT FINDINGS: Careful hemodynamic assessment is critical to the classification of patients with PH and heart failure. Two hemodynamic subgroups of PH in heart failure patients have been described: isolated post-capillary pulmonary hypertension and combined post- and precapillary pulmonary hypertension. The cornerstone in management of PH due to left heart disease is the treatment of the underlying left heart pathology; however, ongoing trials have been designed to test pulmonary vasodilators in this cohort. PH-specific therapies have not demonstrated a benefit in patients with pulmonary hypertension due to left heart disease. Understanding the distinct pathobiology of each hemodynamic subgroup may lead to the development of useful biomarkers and effective targeted therapies.
Subject(s)
Heart Diseases/complications , Heart Failure , Hypertension, Pulmonary/etiology , Ventricular Dysfunction, Left/complications , Heart Diseases/physiopathology , Hemodynamics , Humans , Hypertension, Pulmonary/physiopathology , Vasodilator Agents , Ventricular Dysfunction, Left/physiopathologyABSTRACT
In patients with left ventricular heart failure (HF), the development of pulmonary hypertension (PH) and right ventricular (RV) dysfunction are frequent and have important impact on disease progression, morbidity, and mortality, and therefore warrant clinical attention. Pulmonary hypertension related to left heart disease (LHD) by far represents the most common form of PH, accounting for 65-80% of cases. The proper distinction between pulmonary arterial hypertension and PH-LHD may be challenging, yet it has direct therapeutic consequences. Despite recent advances in the pathophysiological understanding and clinical assessment, and adjustments in the haemodynamic definitions and classification of PH-LHD, the haemodynamic interrelations in combined post- and pre-capillary PH are complex, definitions and prognostic significance of haemodynamic variables characterizing the degree of pre-capillary PH in LHD remain suboptimal, and there are currently no evidence-based recommendations for the management of PH-LHD. Here, we highlight the prevalence and significance of PH and RV dysfunction in patients with both HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), and provide insights into the complex pathophysiology of cardiopulmonary interaction in LHD, which may lead to the evolution from a 'left ventricular phenotype' to a 'right ventricular phenotype' across the natural history of HF. Furthermore, we propose to better define the individual phenotype of PH by integrating the clinical context, non-invasive assessment, and invasive haemodynamic variables in a structured diagnostic work-up. Finally, we challenge current definitions and diagnostic short falls, and discuss gaps in evidence, therapeutic options and the necessity for future developments in this context.
Subject(s)
Heart Failure/complications , Hypertension, Pulmonary/etiology , Ventricular Dysfunction, Left/etiology , Heart Failure/physiopathology , Heart Failure/therapy , Hemodynamics/physiology , Humans , Hypertension, Pulmonary/physiopathology , Hypertension, Pulmonary/therapy , Mitral Valve Insufficiency/surgery , Phenotype , Pulmonary Circulation/physiology , Ventricular Dysfunction, Left/physiopathology , Ventricular Dysfunction, Left/therapySubject(s)
Atenolol/administration & dosage , Blood Pressure/drug effects , Furosemide/administration & dosage , Histoplasmosis , Hypertension, Pulmonary , Female , Histoplasmosis/drug therapy , Histoplasmosis/physiopathology , Humans , Hypertension, Pulmonary/drug therapy , Hypertension, Pulmonary/physiopathology , Middle AgedABSTRACT
BACKGROUND: In the current era, where advanced heart failure (AHF) has become an American Board of Internal Medicine-certified subspecialty, new data are needed to benchmark and value levels of clinical effort performed by AHF specialists (AHFMDs). METHODS AND RESULTS: A 36-question survey was sent to 728 AHFMDs, members of the Heart Failure Society of America, and 224 (31%) responded. Overall, 56% worked in academic medical centers (AMCs) and were younger (48 ± 9 y vs 52 ± 10 y; P < .01) and were represented by a higher proportion of women (34% vs 21%, P < .01) compared with non-AMCs. The percentage of time in clinical care was lower in AMCs (64 ± 19% vs 78 ± 18%; P = .002), with similar concentration on evaluation and management services (79 ± 18% in AMCs vs 72 ± 18 % in non-AMCs; P = NS). The majority of nonclinical time was spent in program administration (10% in both AMCs and non-AMCs) and education/research (15% in AMC vs 5% in non-AMCs). Although 69% of respondents were compensated by work-relative value units (wRVUs), only a small percentage knew their target or the amount of RVUs generated. The mean annual wRVUs generated were lower in AMCs compared to non-AMCs (5,452 ± 1,961 vs 9,071 ± 3,484; P < .001). The annual compensation in AMCs was lower than in non-AMCs (45% vs 10% <$250,000 and 17% vs 61% >$350,000; P < .001) and the satisfaction with compensation was higher in non-AMCs. CONCLUSIONS: AHFMDs' compensation is largely dependent by practice type (AMC vs non-AMC) and clinical productivity as measured by wRVUs. These data provide an opportunity for benchmarking work effort and compensation for AHFMDs, allowing distinction from segments of cardiologists with greater opportunity to accrue procedural wRVUs. They also show several differences between AMCs and non-AMCs that should be considered when formulating work assignment and compensation for AHFMDs.
Subject(s)
Heart Failure/therapy , Income/trends , Outcome Assessment, Health Care , Practice Patterns, Physicians'/standards , Specialization/statistics & numerical data , Surveys and Questionnaires , Academic Medical Centers , Adult , Aged , Attitude of Health Personnel , Benchmarking , Cardiology/standards , Cardiology/trends , Female , Health Care Surveys , Heart Failure/diagnosis , Hospitals, Private , Humans , Male , Middle Aged , Practice Patterns, Physicians'/economics , Severity of Illness Index , Societies, Medical , Specialization/economics , United StatesABSTRACT
Pulmonary hypertension (PH), a common complication of left heart diseases (LHD), negatively impacts symptoms, exercise capacity, and outcome. Although the true prevalence of PH-LHD is unknown, a subset of patients might present significant PH that cannot be explained by a passive increase in left-sided filling pressures. The term "out-of-proportion" PH has been used to identify that population without a clear definition, which has been found less than ideal and created confusion. We propose a change in terminology and a new definition of PH due to LHD. We suggest to abandon "out-of-proportion" PH and to distinguish "isolated post-capillary PH" from "post-capillary PH with a pre-capillary component" on the basis of the pressure difference between diastolic pulmonary artery pressure and pulmonary artery wedge pressure. Although there is no validated treatment for PH-LHD, we provide insights into management and discuss completed and randomized trials in this condition. Finally, we provide recommendations for future clinical trials to establish safety and efficacy of novel compounds to target this area of unmet medical need. (J Am Coll Cardiol 2013;62:D100-8) ©2013 by the American College of Cardiology Foundation.
ABSTRACT
Chronic obstructive lung disease (COPD) and diffuse parenchymal lung diseases (DPLD), including idiopathic pulmonary fibrosis (IPF) and sarcoidosis, are associated with a high incidence of pulmonary hypertension (PH), which is linked with exercise limitation and a worse prognosis. Patients with combined pulmonary fibrosis and emphysema (CPFE) are particularly prone to the development of PH. Echocardiography and right heart catheterization are the principal modalities for the diagnosis of COPD and DPLD. For discrimination between group 1 PH patients with concomitant respiratory abnormalities and group 3 PH patients (PH caused by lung disease), patients should be transferred to a center with expertise in both PH and lung diseases for comprehensive evaluation. The task force encompassing the .authors of this article provided criteria for this discrimination and suggested using the following definitions for group 3 patients, as exemplified for COPD, IPF, and CPFE: COPD/IPF/CPFE without PH (mean pulmonary artery pressure [mPAP]<25mmHg); COPD/IPF/CPFE with PH (mPAP25mmHg); PH-COPD, PH-IPF, and PH-CPFE); COPD/IPF/CPFE with severe PH (mPAP 35 mmHg or mPAP 25 mmHg with low cardiac index [CI <2.0.l/min/m2]; severe PH-COPD, severe PH-IPF, and severe PH-CPFE). The "severe PH group" includes only a minority of chronic lung disease patients who are suspected of having strong general vascular abnormalities (remodeling) accompanying the parenchymal disease and with evidence of an exhausted circulatory reserve rather than an exhausted ventilatory reserve underlying the limitation of exercise capacity. Exertional dyspnea disproportionate to pulmonary function tests, low carbon monoxide diffusion capacity, and rapid decline of arterial oxygenation upon exercise are typical clinical features of this subgroup with poor prognosis. Studies evaluating the effect of pulmonary arterial hypertension drugs currently not approved for group 3 PH patients should focus on this severe PH group, and for the time being, these patients should be transferred to expert centers for individualized patient care. (J Am Coll Cardiol 2013;62:D109-16) ©2013 by the American College of Cardiology Foundation.
ABSTRACT
Information on factors leading to pulmonary arterial hypertension (PAH) treatment discontinuation is limited. This study analyzed 12,902 new PAH medication users to identify predictors of treatment discontinuation. Treatment by accredited pulmonary hypertension centers and combination therapy with PAH agents from different classes were less likely to result in discontinuation.
ABSTRACT
BACKGROUND: Female sex is a significant risk factor for pulmonary arterial hypertension (PAH), yet males with PAH have worse survival - a phenomenon referred to as the "sex paradox" in PAH. METHODS: All adult PAH patients in the Pulmonary Hypertension Association Registry (PHAR) with congruent sex and gender were included. Baseline differences in demographics, hemodynamics, functional parameters, and quality of life were assessed by sex. Kaplan-Meier survival analysis was used to evaluate survival by sex. Mediation analysis was conducted with Cox proportional hazards regression by comparing the unadjusted hazard ratios for sex before and after adjustment for covariates. The plausibility of collider-stratification bias was assessed by modeling how large an unmeasured factor would have to be to generate the observed sex-based mortality differences. Subgroup analysis was performed on idiopathic and incident patients. RESULTS: Among the 1,891 patients included, 75% were female. Compared to men, women had less favorable hemodynamics, lower 6-minute walk distance, more PAH therapies, and worse functional class; however, sex-based differences were less pronounced when accounting for body surface area or expected variability by gender. On multivariate analysis, women had a 48% lower risk of death compared to men (Hazard Ratio 0.52, 95% Confidence interval 0.36 - 0.74, p < 0.001). Modeling found that under reasonable assumptions collider-stratification could account for sex-based differences in mortality. CONCLUSIONS: In this large registry of PAH patients new to a care center, men had worse survival than women despite having more favorable baseline characteristics. Collider-stratification bias could account for the observed greater mortality among men.