Pulmonary vascular effect of insulin in a rodent model of pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is associated with metabolic derangements including insulin resistance, although their effects on the cardiopulmonary disease are unclear. We hypothesized that insulin resistance promotes pulmonary hypertension (PH) development and mutations in type 2 bone morphogenetic protein receptor (BMPR2) cause cellular insulin resistance. Using a BMPR2 transgenic murine model of PAH and two models of inducible diabetes mellitus, we explored the impact of hyperglycemia and/or hyperinsulinemia on development and severity of PH. We assessed insulin signaling and insulin-mediated glucose uptake in human endothelial cells with and without mutations in BMPR2. PH developed in control mice fed a Western diet and PH in BMPR2 mutant mice was increased by Western diet. Pulmonary artery pressure correlated strongly with fasting plasma insulin but not glucose. Reactive oxygen species were increased in lungs of insulin-resistant animals. BMPR2 mutation impaired insulin-mediated endothelial glucose uptake via reduced glucose transporter translocation despite intact insulin signaling. Experimental hyperinsulinemia is strongly associated with PH in both control and BMPR2-mutant mice, though to a greater degree in those with BMPR2 mutation. Human pulmonary endothelial cells with BMPR2 mutation have evidence of reduced glucose uptake due to impaired glucose transporter translocation. These experiments support a role for hyperinsulinemia in pulmonary vascular disease.

Enhancing Insights into Pulmonary Vascular Disease through a Precision Medicine Approach. A Joint NHLBI-Cardiovascular Medical Research and Education Fund Workshop Report

The Division of Lung Diseases of the NHLBI and the Cardiovascular Medical Education and Research Fund held a workshop to discuss how to leverage the anticipated scientific output from the recently launched "Redefining Pulmonary Hypertension through Pulmonary Vascular Disease Phenomics" (PVDOMICS) program to develop newer approaches to pulmonary vascular disease. PVDOMICS is a collaborative, protocol-driven network to analyze all patient populations with pulmonary hypertension to define novel pulmonary vascular disease (PVD) phenotypes. Stakeholders, including basic, translational, and clinical investigators; clinicians; patient advocacy organizations; regulatory agencies; and pharmaceutical industry experts, joined to discuss the application of precision medicine to PVD clinical trials. Recommendations were generated for discussion of research priorities in line with NHLBI Strategic Vision Goals that include: (1) A national effort, involving all the stakeholders, should seek to coordinate biosamples and biodata from all funded programs to a web-based repository so that information can be shared and correlated with other research projects. Example programs sponsored by NHLBI include PVDOMICS, Pulmonary Hypertension Breakthrough Initiative, the National Biological Sample and Data Repository for PAH, and the National Precision Medicine Initiative. (2) A task force to develop a master clinical trials protocol for PVD to apply precision medicine principles to future clinical trials. Specific features include: (a) adoption of smaller clinical trials that incorporate biomarker-guided enrichment strategies, using adaptive and innovative statistical designs; and (b) development of newer endpoints that reflect well-defined and clinically meaningful changes. (3) Development of updated and systematic variables in imaging, hemodynamic, cellular, genomic, and metabolic tests that will help precisely identify individual and shared features of PVD and serve as the basis of novel phenotypes for therapeutic interventions.

A systematic review of transition studies of pulmonary arterial hypertension specific medications

Pulmonary arterial hypertension (PAH) is a progressive potentially fatal disease. Multiple pharmacologic options are now available, which facilitated transitions between different therapeutic options, although the evidence for such transitions has not been well described. We sought to review the evidence supporting the safety and/or efficacy of transitioning between PAH-specific medications. We performed a systematic review of all published studies in the Medline database between 1 January 2000 and 30 June 2016 reporting on any transition between the currently Food and Drug Administration (FDA)-approved PAH-specific medications. Studies reporting on three or more adult patients published in the English language reporting on transitions between FDA-approved PAH medications were extracted and tabulated. Forty-one studies met the selection criteria, nine of which included less than eight patients (and thus were reported separately in the supplement), for a total of 32 studies. Transitioning from parenteral epoprostenol to parenteral treprostinil appears to be safe and efficacious in patients who have less severe disease and more favorable hemodynamics. Transitioning from a prostacyclin analogue to an oral medication may be successful in patients who have favorable hemodynamics and stable disease. There is conflicting evidence supporting the transition from a parenteral to an inhaled prostacyclin analogue, even in patients who are on background oral therapy. Currently, the only evidence in support of transitioning between oral PDE5 inhibitors is from sildenafil to tadalafil. Patients on higher doses of sildenafil are more likely to fail. In patients with liver abnormalities due to bosentan or sitaxentan, the transition to ambrisentan appears to be safe and can result in clinical improvement. Studies regarding PAH medication transitions are limited. Patients who have less severe disease, better functional status, and are on lower medications doses may be more successful at transitioning.

The Role of Transient Receptor Potential Vanilloid 4 in Pulmonary Inflammatory Diseases

Ion channels/pumps are essential regulators of organ homeostasis and disease. In the present review, we discuss the role of the mechanosensitive cation channel, transient receptor potential vanilloid 4 (TRPV4), in cytokine secretion and pulmonary inflammatory diseases such as asthma, cystic fibrosis (CF), and acute lung injury/acute respiratory distress syndrome (ARDS). TRPV4 has been shown to play a role in lung diseases associated with lung parenchymal stretch or stiffness. TRPV4 indirectly mediates hypotonicity-induced smooth muscle contraction and airway remodeling in asthma. Further, the literature suggests that in CF TRPV4 may improve ciliary beat frequency enhancing mucociliary clearance, while at the same time increasing pro-inflammatory cytokine secretion/lung tissue injury. Currently it is understood that the role of TRPV4 in immune cell function and associated lung tissue injury/ARDS may depend on the injury stimulus. Uncovering the downstream mechanisms of TRPV4 action in pulmonary inflammatory diseases is likely important to understanding disease pathogenesis and may lead to novel therapeutics.

Mechanisms of ECG signs in chronic obstructive pulmonary disease

OBJECTIVE

Patients with chronic obstructive pulmonary disease (COPD) often have abnormal ECGs. Our aim was to separate the effects on ECG by airway obstruction, emphysema and right ventricular (RV) afterload in patients with COPD.

METHODS

A cross-sectional study was performed on 101 patients with COPD without left heart disease and 32 healthy age-matched controls. Body mass index (BMI) was measured, and pulmonary function tests, ECG, echocardiography and right heart catheterisation (only patients) were performed. Variables were grouped into (1) airway obstruction by FEV% (percentage of forced expiratory volume)_predicted, (2) emphysema by residual volume/total lung capacity and residual volume (percent of predicted) and (3) RV afterload by mean pulmonary pressure, artery compliance, vascular resistance and RV wall thickness.

RESULTS

In multivariate regression analysis, emphysema correlated negatively to R+S amplitudes in horizontal and frontal leads, RV/left ventricle (LV) end-diastolic volume ratio to horizontal amplitudes and BMI negatively to frontal amplitudes. Increased airway obstruction, RV afterload and BMI correlated with horizontal QRS-axis clockwise rotation. Airway obstruction, RV afterload, RV/LV end-diastolic volume ratio and BMI correlated to the Sokolow-Lyon Index for RV, and RV afterload negatively to Sokolow-LyonIndex for LV. Several classical ECG changes could, however, not be ascribed to specific mechanisms.

CONCLUSIONS

In COPD, the various pathophysiological mechanisms modify the ECG differently. Increased airway obstruction and RV afterload mainly increase the Sokolow-Lyon Index for RV mass and associate with clockwise rotation of the horizontal QRS-axis, whereas emphysema reduces the QRS amplitudes. BMI is an equally important determinant for the majority of the ECG changes.

Oxidative injury of the pulmonary circulation in the perinatal period: Short- and long-term consequences for the human cardiopulmonary system

Development of the pulmonary circulation is a complex process with a spatial pattern that is tightly controlled. This process is vulnerable for disruption by various events in the prenatal and early postnatal periods. Disruption of normal pulmonary vascular development leads to abnormal structure and function of the lung vasculature, causing neonatal pulmonary vascular diseases. Premature babies are especially at risk of the development of these diseases, including persistent pulmonary hypertension and bronchopulmonary dysplasia. Reactive oxygen species play a key role in the pathogenesis of neonatal pulmonary vascular diseases and can be caused by hyperoxia, mechanical ventilation, hypoxia, and inflammation. Besides the well-established short-term consequences, exposure of the developing lung to injurious stimuli in the perinatal period, including oxidative stress, may also contribute to the development of pulmonary vascular diseases later in life, through so-called "fetal or perinatal programming." Because of these long-term consequences, it is important to develop a follow-up program tailored to adolescent survivors of neonatal pulmonary vascular diseases, aimed at early detection of adult pulmonary vascular diseases, and thereby opening the possibility of early intervention and interfering with disease progression. This review focuses on pathophysiologic events in the perinatal period that have been shown to disrupt human normal pulmonary vascular development, leading to neonatal pulmonary vascular diseases that can extend even into adulthood. This knowledge may be particularly important for ex-premature adults who are at risk of the long-term consequences of pulmonary vascular diseases, thereby contributing disproportionately to the burden of adult cardiovascular disease in the future.

Resolution of myelofibrosis-associated pulmonary arterial hypertension following allogeneic hematopoietic stem cell transplantation

We present the case of a 62-year-old man with myelofibrosis-associated pulmonary arterial hypertension (PAH) who underwent allogeneic hematopoietic stem cell transplantation with subsequent resolution of disease and PAH. Right heart catheterization was used to guide PAH therapy before and after transplantation. Drug interactions, adverse effects, and renal insufficiency posed clinical challenges for the management of PAH-specific medications after transplantation. PAH improved soon after transplantation, and vasoactive medications were tapered off. Resolution of PAH was confirmed with repeat measurement of pulmonary hemodynamic characteristics. Although the etiology and pathophysiology for the resolution of PAH was unclear, the myelopulmonary pathophysiologic link was likely to have contributed. This is the first report describing resolution of myelofibrosis-associated PAH after allogeneic hematopoietic stem cell transplantation.

Role of B-Type Natriuretic Peptide in Predicting In-Hospital Outcomes in Acute Exacerbation of Chronic Obstructive Pulmonary Disease With Preserved Left Ventricular Function: A 5-Year Retrospective Analysis

BACKGROUND

The role of B-type natriuretic peptide (BNP) is less understood in the risk stratification of patients with an acute exacerbation of chronic obstructive pulmonary disease (AECOPD), especially in patients with normal left ventricular ejection fraction (LVEF).

METHODS

This retrospective study from 2008 to 2012 evaluated all adult patients with AECOPD having BNP levels and available echocardiographic data demonstrating LVEF ≥40%. The patients were divided into groups 1, 2, and 3 with BNP ≤ 100, 101 to 500, and ≥501 pg/mL, respectively. A subgroup analysis was performed for patients without renal dysfunction. Outcomes included need for and duration of noninvasive ventilation (NIV) and mechanical ventilation (MV), NIV failure, reintubation at 48 hours, intensive care unit (ICU) and total length of stay (LOS), and in-hospital mortality. Two-tailed P < .05 was considered statistically significant.

RESULTS

Of the total 1145 patients, 550 (48.0%) met our inclusion criteria (age 65.1 ± 12.2 years; 271 [49.3%] males). Groups 1, 2, and 3 had 214, 216, and 120 patients each, respectively, with higher comorbidities and worse biventricular function in higher categories. Higher BNP values were associated with higher MV use, NIV failure, MV duration, and ICU and total LOS. On multivariate analysis, BNP was an independent predictor of higher NIV and MV use, NIV failure, NIV and MV duration, and total LOS in groups 2 and 3 compared to group 1. B-type natriuretic peptide continued to demonstrate positive correlation with NIV and MV duration and ICU and total LOS independent of renal function in a subgroup analysis.

CONCLUSION

Elevated admission BNP in patients with AECOPD and normal LVEF is associated with worse in-hospital outcomes and can be used to risk-stratify these patients.

Integration of complex data sources to provide biologic insight into pulmonary vascular disease (2015 Grover Conference Series)

The application of complex data sources to pulmonary vascular diseases is an emerging and promising area of investigation. The use of -omics platforms, in silico modeling of gene networks, and linkage of large human cohorts with DNA biobanks are beginning to bear biologic insight into pulmonary hypertension. These approaches to high-throughput molecular phenotyping offer the possibility of discovering new therapeutic targets and identifying variability in response to therapy that can be leveraged to improve clinical care. Optimizing the methods for analyzing complex data sources and accruing large, well-phenotyped human cohorts linked to biologic data remain significant challenges. Here, we discuss two specific types of complex data sources-gene regulatory networks and DNA-linked electronic medical record cohorts-that illustrate the promise, challenges, and current limitations of these approaches to understanding and managing pulmonary vascular disease.

Up-regulation of the mammalian target of rapamycin complex 1 subunit Raptor by aldosterone induces abnormal pulmonary artery smooth muscle cell survival patterns to promote pulmonary arterial hypertension

Activation of the mammalian target of rapamycin complex 1 (mTORC1) subunit Raptor induces cell growth and is a downstream target of Akt. Elevated levels of aldosterone activate Akt, and, in pulmonary arterial hypertension (PAH), correlate with pulmonary arteriole thickening, which suggests that mTORC1 regulation by aldosterone may mediate adverse pulmonary vascular remodeling. We hypothesized that aldosterone-Raptor signaling induces abnormal pulmonary artery smooth muscle cell (PASMC) survival patterns to promote PAH. Remodeled pulmonary arterioles from SU-5416/hypoxia-PAH rats and monocrotaline-PAH rats with hyperaldosteronism expressed increased levels of the Raptor target, p70S6K, which provided a basis for investigating aldosterone-Raptor signaling in human PASMCs. Aldosterone (10(-9) to 10(-7) M) increased Akt/mTOR/Raptor to activate p70S6K and increase proliferation, viability, and apoptosis resistance in PASMCs. In PASMCs transfected with Raptor-small interfering RNA or treated with spironolactone/eplerenone, aldosterone or pulmonary arterial plasma from patients with PAH failed to increase p70S6K activation or to induce cell survival in vitro Optimal inhibition of pulmonary arteriole Raptor was achieved by treatment with Staramine-monomethoxy polyethylene glycol that was formulated with Raptor-small interfering RNA plus spironolactone in vivo, which decreased arteriole muscularization and pulmonary hypertension in 2 experimental animal models of PAH in vivo Up-regulation of mTORC1 by aldosterone is a critical pathobiologic mechanism that controls PASMC survival to promote hypertrophic vascular remodeling and PAH.-Aghamohammadzadeh, R., Zhang, Y.-Y., Stephens, T. E., Arons, E., Zaman, P., Polach, K. J., Matar, M., Yung, L.-M., Yu, P. B., Bowman, F. P., Opotowsky, A. R., Waxman, A. B., Loscalzo, J., Leopold, J. A., Maron, B. A. Up-regulation of the mammalian target of rapamycin complex 1 subunit Raptor by aldosterone induces abnormal pulmonary artery smooth muscle cell survival patterns to promote pulmonary arterial hypertension.

Pulmonary arterial hypertension in primary amyloidosis

Amyloidosis involves extravascular deposition of fibrillar proteins within tissues and organs. Primary light chain amyloidosis represents the most common form of systemic amyloidosis involving deposition of monoclonal immunoglobulin light chains. Although pulmonary amyloid deposition is common in primary amyloidosis, clinically significant pulmonary amyloidosis is uncommon, and elevated pulmonary artery pressures are rarely observed in the absence of other underlying etiologies for pulmonary hypertension, such as elevated filling pressures secondary to cardiac amyloid. In this case report, we present a patient with primary light chain amyloidosis and pulmonary arterial hypertension in the setting of pulmonary vascular and right ventricular myocardial amyloid deposition.

Left bronchial compression and pulmonary hypertension related to anomalous right pulmonary artery

Anomalous origin of a pulmonary artery from the ascending aorta is a congenital defect that can be complicated by pulmonary arterial hypertension, typically due to vascular disease if the anomaly is left uncorrected past 6 months of age. We describe a unique case of severe pulmonary arterial hypertension with this defect in a 1-month-old infant unexpectedly caused instead by bronchial compression from her dilated left pulmonary artery.

Abnormalities in hyperpolarized (129)Xe magnetic resonance imaging and spectroscopy in two patients with pulmonary vascular disease

The diagnosis of pulmonary vascular disease (PVD) is usually based on hemodynamic and/or clinical criteria. Noninvasive imaging of the heart and proximal vasculature can also provide useful information. An alternate approach to such criteria in the diagnosis of PVD is to image the vascular abnormalities in the lungs themselves. Hyperpolarized (HP) (129)Xe magnetic resonance imaging (MRI) is a novel technique for assessing abnormalities in ventilation and gas exchange in the lungs. We applied this technique to two patients for whom there was clinical suspicion of PVD. Two patients who had significant hypoxemia and dyspnea with no significant abnormalities on computed tomography imaging or ventilation-perfusion scan and only mild or borderline pulmonary arterial hypertension at catheterization were evaluated. They underwent HP (129)Xe imaging and subsequently had tissue diagnosis obtained from lung pathology. In both patients, HP (129)Xe imaging demonstrated normal ventilation but markedly decreased gas transfer to red blood cells with focal defects on imaging, a pattern distinct from those previously described for idiopathic pulmonary fibrosis or obstructive lung disease. Pathology on both patients later demonstrated severe PVD. These findings suggest that HP (129)Xe MRI may be useful in the diagnosis of PVD and monitoring response to therapy. Further studies are required to determine its sensitivity and specificity in these settings.

Gestational pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a progressive disease marked by the irreversible pulmonary vascular changes of vasoconstriction, thrombosis, and proliferation of smooth muscle and endothelial cells. The untreated clinical course is characterized by progressive dyspnea and a median survival of less than 3 years. Many of these patients are of child-bearing age; however, pregnancy leads to physiologic changes that are particularly poorly tolerated in PAH, conferring a 30%-56% mortality. We present a case of PAH that spontaneously resolved after termination of pregnancy and recurred during each of two subsequent pregnancies. To our knowledge, this case is unique, because no cases of spontaneous resolution of idiopathic PAH have been reported in adults, nor have there been any reports of pulmonary hypertension that is isolated to the gestational period.

Endothelial HIF signaling regulates pulmonary fibrosis-associated pulmonary hypertension

Pulmonary hypertension (PH) complicating chronic parenchymal lung disease, such as idiopathic pulmonary fibrosis, results in significant morbidity and mortality. Since the hypoxia-inducible factor (HIF) signaling pathway is important for development of pulmonary hypertension in chronic hypoxia, we investigated whether HIF signaling in vascular endothelium regulates development of PH related to pulmonary fibrosis. We generated a transgenic model in which HIF is deleted within vascular endothelial cells and then exposed these mice to chronic intraperitoneal bleomycin to induce PH associated with lung fibrosis. Although no differences in the degree of fibrotic remodeling were observed, we found that endothelial HIF-deficient mice were protected against development of PH, including right ventricle and pulmonary vessel remodeling. Similarly, endothelial HIF-deficient mice were protected from PH after a 4-wk exposure to normobaric hypoxia. In vitro studies of pulmonary vascular endothelial cells isolated from the HIF-targeted mice and controls revealed that endothelial HIF signaling increases endothelial cell expression of connective tissue growth factor, enhances vascular permeability, and promotes pulmonary artery smooth muscle cell proliferation and wound healing ability, all of which have the potential to impact the development of PH in vivo. Taken together, these studies demonstrate that vascular endothelial cell HIF signaling is necessary for development of hypoxia and pulmonary fibrosis associated PH. As such, HIF and HIF-regulated targets represent a therapeutic target in these conditions.

Convex probe endobronchial ultrasound: applications beyond conventional indications

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is maturing and gaining acceptance by more and more clinicians for lymph node staging of lung cancer and diagnosis of mediastinal and hilar masses or lymph node enlargement by convex probe endobronchial ultrasound (CP-EBUS). The application of CP-EBUS, however, is not limited to conventional indications. Diagnostically, elastography is a new technology for the differentiation of benign and malignant lymph nodes before aspiration. CP-EBUS can also be used for pulmonary vascular diseases, such as pulmonary embolism (PE) and non-thrombotic endovascular lesions (NELs). Therapeutically, CP-EBUS can be used for cyst drainage and drug injections. CP-EBUS is not limited to observation and aspiration of mediastinal masses and lymph nodes, but is also suitable for exploration of other tissues external to the central airway, which necessitates unprecedented skills for the bronchoscopist.

Early pulmonary vascular disease in preterm infants at risk for bronchopulmonary dysplasia

RATIONALE

Pulmonary hypertension (PH) is associated with poor outcomes among preterm infants with bronchopulmonary dysplasia (BPD), but whether early signs of pulmonary vascular disease are associated with the subsequent development of BPD or PH at 36 weeks post-menstrual age (PMA) is unknown.

OBJECTIVES

To prospectively evaluate the relationship of early echocardiogram signs of pulmonary vascular disease in preterm infants to the subsequent development of BPD and late PH (at 36 wk PMA).

METHODS

Prospectively enrolled preterm infants with birthweights 500-1,250 g underwent echocardiogram evaluations at 7 days of age (early) and 36 weeks PMA (late). Clinical and echocardiographic data were analyzed to identify early risk factors for BPD and late PH.

MEASUREMENTS AND MAIN RESULTS

A total of 277 preterm infants completed echocardiogram and BPD assessments at 36 weeks PMA. The median gestational age at birth and birthweight of the infants were 27 weeks and 909 g, respectively. Early PH was identified in 42% of infants, and 14% were diagnosed with late PH. Early PH was a risk factor for increased BPD severity (relative risk, 1.12; 95% confidence interval, 1.03-1.23) and late PH (relative risk, 2.85; 95% confidence interval, 1.28-6.33). Infants with late PH had greater duration of oxygen therapy and increased mortality in the first year of life (P < 0.05).

CONCLUSIONS

Early pulmonary vascular disease is associated with the development of BPD and with late PH in preterm infants. Echocardiograms at 7 days of age may be a useful tool to identify infants at high risk for BPD and PH.

Advances in paediatric pulmonary vascular disease associated with bronchopulmonary dysplasia

Pulmonary hypertension (PH) is a common finding in infants with bronchopulmonary dysplasia (BPD). The aim of this review is to describe recent advances in the diagnosis and treatment of PH and discuss whether they will benefit infants and children with BPD related PH. Echocardiography remains the mainstay of diagnosis but has limitations, further developments in diagnostic techniques and identification of biomarkers are required. There are many potential therapies for PH associated with BPD. Inhaled nitric oxide has been shown to improve short term outcomes only. Sidenafil in resource limited settings was shown in three randomized trials to significantly reduce mortality. The efficacy of other therapies including prostacyclin, PDE3 inhibitors and endothelin receptor blockers has only been reported in case reports or case series. Randomized controlled trials with long term follow up are required to appropriately assess the efficacy of therapies aimed at improving the outcome of children with PH.

The role of phosphodiesterase inhibitors in the management of pulmonary vascular diseases

Phosphodiesterase inhibitors (PDE) can be used as therapeutic agents for various diseases such as dementia, depression, schizophrenia and erectile dysfunction in men, as well as congestive heart failure, chronic obstructive pulmonary disease, rheumatoid arthritis, other inflammatory diseases, diabetes and various other conditions. In this review we will concentrate on one type of PDE, mainly PDE5 and its role in pulmonary vascular diseases.

Impaired right ventricular-pulmonary vascular function in myeloproliferative neoplasms

BACKGROUND

Increased bone marrow hemangioblast numbers, alterations in erythroid/myeloid lineages, increased reticulin, and greater circulating bone marrow progenitor cells are present in patients with pulmonary arterial hypertension (PAH). The data suggest that myeloid progenitors contribute to the pathogenesis of PAH, but there are little data on the prevalence of pulmonary vascular disease among the different forms of myeloid diseases. We hypothesized that there would be a higher prevalence of pulmonary vascular disease in myeloproliferative neoplasms that have high circulating progenitor cells, such as myelofibrosis and chronic myelogenous leukemia (CML), compared with those with low circulating progenitors, such as in aplastic anemia.

METHODS

Patients with myelofibrosis, CML, and aplastic anemia who underwent echocardiographic evaluation of cardiac function in preparation for bone marrow transplantation at the Cleveland Clinic between 1997 and 2012 were identified and their electronic medical records were queried for demographic data, blood cell counts, and pulmonary function tests. All echocardiograms were uniformly analyzed in a blinded fashion by an advanced sonographer and cardiologist for measures of right and left ventricular function and estimation of pulmonary vascular disease.

RESULTS

Gender and race distribution among disease groups was similar. Patients with myelofibrosis (n = 19) and aplastic anemia (n = 30) had increased right ventricle (RV) wall thickness compared with CML (n = 82) patients (aplastic anemia, 0.7 ± 0.1; CML, 0.5 ± 0.1; and myelofibrosis, 0.7 ± 0.1; p = 0.02). Patients with myelofibrosis had higher levels of estimated RV systolic pressure compared with the other groups (aplastic anemia, 29.9 ± 1.5; CML, 26.2 ± 1.1; and myelofibrosis, 36.7 ± 3.7 mm Hg; p < 0.01).

CONCLUSIONS

The findings suggest an important role for myeloid progenitors in the maintenance of pulmonary-vascular health, in which abnormal myeloproliferative progenitors are associated with RV pathology.

Prevalence of overestimation or underestimation of the functional capacity using MRC score as compared to 6-minute walk test in patients with cardio-respiratory disorders

OBJECTIVES

The first objective of our study was to assess whether patients diagnosed with cardio-respiratory disorders report overestimation or underestimation on recall (Medical Research Council (MRC) dyspnea scale) of their true functional capacity (walked distance during a 6-minute walk test (6MWT)). The second objective was to assess whether the measurement of breathlessness at the end of a 6MWT (Borg score) may help to identify dyspneic patients on recall.

METHODS

The 6MWTs of 746 patients aged from 40 to 80 years who were diagnosed with either chronic obstructive pulmonary disease (COPD, n = 355), diffuse parenchymal lung disease (n = 140), pulmonary vascular diseases (n = 188) or congestive heart failure (n = 63) were selected from a prospective Clinical Database Warehouse.

RESULTS

The percentage of patients who overestimated (MRC ≤ 2 with distance < lower limit of normal (LLN), 61/746, 8%; 95% confidence interval (CI): 6 to 10%) or underestimated (MRC > 2 with distance ≥LLN, 121/746, 16%; 95%CI: 14 to 19%) on recall their capacity was elevated. The overestimation seemed related to self-limitation, while the underestimation seemed related to patients who "work through" their breathing discomfort. These two latter groups of patients were mainly diagnosed with COPD. A Borg dyspnea score >3 (upper limit of normal) at the end of the 6MWT had 84% specificity for the prediction of a MRC score >1.

CONCLUSION

Almost one fourth of patients suffering from cardio-pulmonary disorders overestimate or underestimate on recall their true functional capacity. An elevated Borg dyspnea score at the end of the 6MWT has a good specificity to predict dyspnea on recall.

Pulmonary hypertension due to left heart diseases

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.

Capillary hemangiomatosis like-lesions in lung biopsies from children with congenital heart defects

The morphological findings in the lung vessels of children with pulmonary arterial hypertension associated with uncorrected congenital cardiac shunts may be qualitatively and quantitatively assessed by lung biopsy in selected cases. Among 297 lung biopsies collected over a period of 11 years two cases were detected presenting the typical findings of pulmonary capillary hemangiomatosis, a rare disorder usually associated with pulmonary veno-occlusive disease. We report the clinical and histological findings and discuss about the impact of this unexpected and not-previously described associated lesion on the prognosis and on the therapeutic strategy in patients with pulmonary hypertension associated with congenital heart disease.

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.