Pulmonary arterial hypertension in primary myelofibrosis is common and associated with an altered angiogenic status

Ten years of treatment with ruxolitinib for myelofibrosis: a review of safety

Myelofibrosis (MF) is a chronic myeloproliferative neoplasm characterized by bone marrow fibrosis, anemia, extramedullary hematopoiesis, and splenomegaly. Patients with MF are at risk for reduced survival versus the general population and often experience burdensome signs and symptoms that reduce quality of life. The oral Janus kinase (JAK) 1/JAK2 inhibitor ruxolitinib was initially approved by the US Food and Drug Administration in 2011 for the treatment of patients with intermediate or high-risk MF, including primary MF, post-polycythemia vera MF, and post-essential thrombocythemia MF, based on efficacy and safety findings from the randomized, controlled, phase 3 COMFORT trials. Over a decade later, ruxolitinib continues to be the standard of care in higher-risk MF, and dose optimization and management remain crucial for safely maximizing clinical benefits of ruxolitinib. This review summarizes the safety profile of ruxolitinib in patients with MF in the COMFORT trials leading up to approval and in the subsequent JUMP, ROBUST, EXPAND, and REALISE trials; in pooled analyses; and in postmarketing analyses in the 10 years following approval. There is a focus on the occurrence of common hematologic and nonhematologic adverse events, with guidance provided on the management of patients with anemia or thrombocytopenia, including dosing strategies based on findings from the REALISE and EXPAND trials. Finally, to ensure a greater understanding of the safety profile of ruxolitinib, practical considerations are discussed.

Pulmonary hypertension is associated with poor cardiovascular and hematologic outcomes in patients with myeloproliferative neoplasms and cardiovascular disease

Cardiovascular events and hematologic progression to myelofibrosis or leukemia are leading causes of morbidity and mortality among patients with myeloproliferative neoplasms (MPN). Pulmonary hypertension (PH) is also associated with MPN and cardiovascular disease (CVD), though its prognostic significance in MPN is not well characterized. Our primary objective was to investigate the effect of PH, defined as right-ventricular systolic pressure (RVSP) ≥ 50 mmHg on echocardiogram or mean pulmonary artery pressure (mPAP) ≥ 20 on right heart catheterization, on cardiovascular and all-cause mortality and hematologic progression in patients with MPN and CVD (atrial fibrillation, heart failure hospitalization, and myocardial infarction after MPN diagnosis). Of the 197 patients included (86 ET, 80 PV, 31 PMF), 92 (47%) had PH and 98 (50%) were male. All-cause mortality (58 vs 37%, p = 0.004), cardiovascular death (35 vs 9%, p < 0.0001), and hematologic progression (23 vs 11%, p = 0.037) occurred more frequently in patients with PH. Multivariable competing-risk and proportional hazards regression showed that PH was associated with increased risk of all-cause death (adjusted hazard ratio [HR], 1.80, 95% CI 1.10-2.93), CV death (adjusted subdistribution HR 3.71, 95% CI 1.58-8.73), and hematologic progression (adjusted subdistribution HR 1.99, 95% CI 1.21-3.27).

[Pulmonary Hypertension and Polycythemia vera]

INTRODUCTION

 Chronic myeloproliferative diseases are rare causes of PH class 5 according to Nice classification 2018. The present case reports show different courses, on the one hand with a primary manifestation of a PH and subsequently a PV, on the other hand with the development of a PH in the context of a PV.

CASE REPORTS

 1) At first contact, a 75-year-old female patient who complained progressive dyspnea and had evidence of stress-PH in the right heart catheter. During the course she developed a resting PH of up to 70 mmHg systolic despite initial monotherapy and subsequent dual therapy for PH. After 5 years she had the diagnosis of polycythemia vera, treated with hydroxycarbamide and subsequent phlebotomies. In the further course increasing cardiac decompensation and death. 2) 74-year-old female patient at the time of diagnosis of chronic megakaryocytic-granulocytic myelosis. After 7 years, evidence of polycythemia vera (V617F mutation in the JAK2 gene), a monoclonal gammopathy. In the case of splenomegaly, irradiation of the spleen was carried out and, after 1 year, therapy with ruxolitinib was started. After another 2 years, with increasing dyspnea, pulmonary hypertension (CTEPH) with a PA-mean of 43 mmHg and a PVR of 4.5 WE were detected. With anticoagulation and riociguat therapy exercise capacity and PA pressures were only temporarily improved. Within 1 year restrictive ventilation, hypoxemia, heart failure (EF 45 %) with leading right heart decompensation and cardiorenal syndrome developed. Dialysis showed only short-term recompensation, and the patient died.

DISCUSSION

 The case reports are characterized by a combination of PV and PH, with different temporal sequence, as well as only a low influence of PH-specific therapy, with subsequent progressive cardiac decompensation. Thus, they reflect the different etiologies, clinical manifestations, and the low therapeutic influence of PH in myeloproliferative disorders. The value of PH-specific therapy remains unclear, especially in view of different pathomechanisms in the genesis of PH.

CONCLUSION

 Patients with myeloproliferative diseases require screening for PH. In the course of PH, myeloproliferative disease can unmask or develop. The therapeutic influence on PH is limited.

Integrated bioinformatic analysis reveals the underlying molecular mechanism of and potential drugs for pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a devastating cardiovascular disease without a clear mechanism or drugs for treatment. Therefore, it is crucial to reveal the underlying molecular mechanism and identify potential drugs for PAH. In this study, we first integrated three human lung tissue datasets (GSE113439, GSE53408, GSE117261) from GEO. A total of 151 differentially expressed genes (DEGs) were screened, followed by KEGG and GO enrichment analyses and PPI network construction. Five hub genes (CSF3R, NT5E, ANGPT2, FGF7, and CXCL9) were identified by Cytoscape (Cytohubba). GSEA and GSVA were performed for each hub gene to uncover the potential mechanism. Moreover, to repurpose known and therapeutic drugs, the CMap database was retrieved, and nine candidate compounds (lypressin, ruxolitinib, triclabendazole, L-BSO, tiaprofenic acid, AT-9283, QL-X-138, huperzine-a, and L-741742) with a high level of confidence were obtained. Then ruxolitinib was selected to perform molecular docking simulations with ANGPT2, FGF7, NT5E, CSF3R, JAK1, JAK2, JAK3, TYK2. A certain concentration of ruxolitinib could inhibit the proliferation and migration of rat pulmonary artery smooth muscle cells (rPASMCs) in vitro. Together, these analyses principally identified CSF3R, NT5E, ANGPT2, FGF7 and CXCL9 as candidate biomarkers of PAH, and ruxolitinib might exert promising therapeutic action for PAH.

The Role of JAK/STAT Molecular Pathway in Vascular Remodeling Associated with Pulmonary Hypertension

Pulmonary hypertension is defined as a group of diseases characterized by a progressive increase in pulmonary vascular resistance (PVR), which leads to right ventricular failure and premature death. There are multiple clinical manifestations that can be grouped into five different types. Pulmonary artery remodeling is a common feature in pulmonary hypertension (PH) characterized by endothelial dysfunction and smooth muscle pulmonary artery cell proliferation. The current treatments for PH are limited to vasodilatory agents that do not stop the progression of the disease. Therefore, there is a need for new agents that inhibit pulmonary artery remodeling targeting the main genetic, molecular, and cellular processes involved in PH. Chronic inflammation contributes to pulmonary artery remodeling and PH, among other vascular disorders, and many inflammatory mediators signal through the JAK/STAT pathway. Recent evidence indicates that the JAK/STAT pathway is overactivated in the pulmonary arteries of patients with PH of different types. In addition, different profibrotic cytokines such as IL-6, IL-13, and IL-11 and growth factors such as PDGF, VEGF, and TGFβ1 are activators of the JAK/STAT pathway and inducers of pulmonary remodeling, thus participating in the development of PH. The understanding of the participation and modulation of the JAK/STAT pathway in PH could be an attractive strategy for developing future treatments. There have been no studies to date focused on the JAK/STAT pathway and PH. In this review, we focus on the analysis of the expression and distribution of different JAK/STAT isoforms in the pulmonary arteries of patients with different types of PH. Furthermore, molecular canonical and noncanonical JAK/STAT pathway transactivation will be discussed in the context of vascular remodeling and PH. The consequences of JAK/STAT activation for endothelial cells and pulmonary artery smooth muscle cells’ proliferation, migration, senescence, and transformation into mesenchymal/myofibroblast cells will be described and discussed, together with different promising drugs targeting the JAK/STAT pathway in vitro and in vivo.

Epidemiology, Pathogenesis, and Clinical Approach in Group 5 Pulmonary Hypertension

Pulmonary hypertension (PH) is recognized to be associated with a number of comorbid conditions. Based on these associations, PH is classified into 5 groups, considering common pathophysiologic drivers of disease, histopathologic features, clinical manifestations and course, and response to PH therapy. However, in some of these associated conditions, these characteristics are less well-understood. These include, among others, conditions commonly encountered in clinical practice such as sarcoidosis, sickle cell disease, myeloproliferative disorders, and chronic kidney disease/end stage renal disease. PH in these contexts presents a significant challenge to clinicians with respect to disease management. The most recent updated clinical classification schemata from the 6th World Symposium on PH classifies such entities in Group 5, highlighting the often unclear and/or multifactorial nature of PH. An in-depth review of the state of the science of Group 5 PH with respect to epidemiology, pathogenesis, and management is provided. Where applicable, future directions with respect to research needed to enhance understanding of the clinical course of these entities is also discussed.

Evaluation of hemodynamic parameters among patients with myeloproliferative neoplasms and suspected pulmonary hypertension

Myeloproliferative neoplasms (MPNs) are associated with pulmonary hypertension (PH). We studied MPN patients who underwent right-heart-catheterization (RHC) to identify hemodynamic differences between MPN-subtypes. Per RHC, hemodynamics were classified as pre, post or combined pre and post-capillary PH. One-way analysis-of-variance (ANOVA) was used to compare hemodynamic differences among MPN-subtypes. Correlation of RVSP between trans-thoracic echocardiography (TTE) and RHC was evaluated. We included 68 patients. Median age was 63. Fifty-nine percent were male and 87% Caucasian. Polycythemia vera and essential thrombocythemia were the most common subtypes. On TTE, 91.5% had PH. On RHC, only 29% met criteria for pre-capillary PH. No MPN-subtype was more likely than others to have pre-capillary PH. Bland-Altman analysis showed significant intra-person variability between TTE and RHC-derived right ventricular systolic pressures. Post-capillary involvement is more common than precapillary PH in MPN. Type of PH does not appear to differ by MPN-subtype.

Prevalence and risk factors for Pulmonary Hypertension associated with chronic Myeloproliferative Neoplasms

OBJECTIVES

Pulmonary hypertension (PH) is commonly reported in Philadelphia-chromosome negative myeloproliferative neoplasms (MPNs) including polycythemia vera (PV), essential thrombocythemia (ET), and myelofibrosis (MF). PH may be diagnosed directly by right heart catheterization (RHC) or estimated by transthoracic echocardiography (TTE). Survival is shortened by PH but despite the potential significance of PH to management and prognosis of MPN, estimates of its prevalence in MPNs vary and risk factors for the condition are poorly established. We performed a systematic review and meta-analysis of available studies to fill this void.

METHODS

We searched EMBASE, MEDLINE, and Clinicaltrials.gov for the terms "pulmonary hypertension," "myeloproliferative disorders," "polycythemia vera," "essential thrombocythemia," and "myelofibrosis." We restricted analysis to the 1999-2019 window to improve uniformity of MPN diagnostic criteria. We retrieved 221 records and, after abstract and full-text screening, identified 17 papers meeting criteria for inclusion in our meta-analysis. A modified Newcastle-Ottawa scale was used to assess quality.

RESULTS

Results for 935 patients were available, 309 of these having PH (33%). Using logistic mixed-effect regression, we found that diagnosis mode (RHC vs TTE) and MPN duration influenced PH prevalence. Studies employing predominantly TTE yielded prevalence estimates ~5-fold higher than those using RHC (35% vs 7.2%). We identified MF and duration of MPN as significant risk factors for development of PH.

CONCLUSIONS

Prevalence of PH in MPNs is poorly understood with estimates ranging from 3.8% to 58%. Patients with MF and longer duration of disease seem at particularly high risk and should be carefully monitored for PH.

BCR-ABL1-Negative Chronic Myeloproliferative Neoplasms and Pulmonary Hypertension: A Prospective Long-Term Follow-up Study of the Impact of Pulmonary Hypertension on Survival

PURPOSE

To assess the prevalence of PHT in patients with BCR-ABL1-negative CMPN and to evaluate impact of PHT on survival during long-term follow-up.

PATIENTS AND METHODS

A total of 122 patients with BCR-ABL1-negative CMPN underwent transthoracic echocardiographic (TTE) evaluation at the beginning of study. Patients undergoing PHT on TTE examination were also evaluated by a pulmonologist. Patients were divided into 3 groups. Group A comprised patients with CMPN-related PHT; group B, patients with no PHT; and group C, patients with PHT due to secondary causes. Patients were evaluated again every 3 to 6 months.

RESULTS

PHT was detected in 33 (27%) of 122 patients. Eight (6.5%) had CMPN-related PHT and the remaining 25 (20.5%) had non-CMPN-related PHT. Positivity for JAK2 V617F mutation in the study population was 72.9%. Groups were similar with respect to hematologic parameters and gender. Follow-up times were as follows: median (range) time from diagnosis to TTE and study end were 34 (1-158) months and 107 (16-251) months, respectively, and from TTE to study end was 88 (7-110) months. No significant differences found among the groups in terms of median time from diagnosis to TTE, follow-up, and overall survival.

CONCLUSION

BCR-ABL1-negative CMPN patients had a lower prevalence of PHT compared to earlier studies. There was no statistically significant difference in median overall survival between patients with or without PHT. This may be because patients with PHT were asymptomatic and PHT was mild. The impact of PHT on survival was negligible.

Prevalence and risk factors of high echocardiographic probability of pulmonary hypertension in myeloproliferative neoplasms patients

Pulmonary hypertension (PH) is emerging as a complication of myeloproliferative neoplasms (MPNs). This was a prospective study conducted at Chiang Mai University Hospital. The primary objective was to determine the prevalence of high echocardiographic probability of PH in MPNs patients. The secondary objectives were to determine risk factors of PH and the correlation between risk factors and peak tricuspid regurgitation velocity (TRV_max). All MPNs patients aged over 18 years, including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), were enrolled. All eligible patients underwent echocardiography for evaluation of the probability of PH in line with the 2015 European Society of Cardiology (ESC) and the European Respiratory Society (ERS) Guidelines. Sixty-six patients with a median age of 59 years were enrolled. There were 35 PV, 25 ET, and 6 PMF patients included. The prevalence of high echocardiographic probability of PH was 4.55% (2 ET and 1 PMF). Risk factors associated with high echocardiographic probability of PHT were not analyzed. There were three risk factors associated with increased TRV_max, specifically lower hemoglobin, older age, and the presence of JAK2V617F mutation. The prevalence of high echocardiographic probability of PH in MPNs patients was 4.55%.

Pulmonary hypertension in patients with Philadelphia-negative myeloproliferative neoplasms: a single-center retrospective analysis of 225 patients

Background

The prevalence of pulmonary hypertension (PH) in myeloproliferative neoplasms (MPNs) varies among studies. We analyzed the prevalence of PH in Korean patients with Philadelphia-negative (Ph^-) MPNs.

Methods

Medical records of patients with Ph^- MPNs [essential thrombocythemia (ET), polycythemia vera (PV), or primary myelofibrosis (PMF)] visiting a single hospital between 1993 and 2019 were reviewed retrospectively. Transthoracic echocardiographic examination (TTE) results were reviewed and PH was diagnosed according to established guidelines.

Results

Of the 320 MPN (179 ET, 107 PV, and 34 PMF) patients, 225 (121 ET, 83 PV, and 21 PMF) underwent TTE. Of these 225 MPN patients, 19 of 121 (15.7%) ET, 9 of 83 (10.8%) PV, and 6 of 21 (28.6%) PMF patients had PH. PV patients with PH were older [71 (42‒85) vs. 61.5 (26‒91) yr, respectively; P=0.049], predominantly female (male:female ratio, 0.29 vs. 1.96, respectively; P=0.010), had lower hemoglobin levels (15.9±2.6 g/dL vs. 18.4±2.6 g/dL, respectively; P=0.010), and higher platelet counts (616.6±284.2×10⁹/L vs. 437.7±191.7×10⁹/L, respectively; P=0.020) than PV patients without PH. PMF patients with PH had higher monocyte counts (1.3±0.5×10⁹/L vs. 0.8±0.4×10⁹/L, respectively; P=0.031) than those without PH. PH was a risk factor for poor survival in PV (HR, 12.4; 95% CI, 1.8‒86.6).

Conclusion

PH is common in patients with Ph^- MPNs and hence, careful screening for PH is warranted.

A provider's guide to primary myelofibrosis: pathophysiology, diagnosis, and management

Although understanding of the pathogenesis and molecular biology of primary myelofibrosis continues to improve, treatment options are limited, and several biological features remain unexplained. With an appropriate clinical history, exam, laboratory evaluation, and bone marrow biopsy, the diagnosis can often be established. Recent studies have better characterized prognostic factors and driver mutations in myelofibrosis, facilitated by use of next-generation sequencing. These advances have facilitated development of a management strategy that is based on both risk factors and clinical phenotype. For low-risk patients, treatment will depend on symptom severity. For patients with higher-risk disease, several treatments are available including JAK inhibitors, allogeneic hematopoietic stem cell transplant, and clinical trials using novel molecularly targeted therapies and rational drug combinations. In this review, we outline what is known about the disease pathogenesis, discuss an approach to reaching the diagnosis, review the prognosis of myelofibrosis, and detail current therapeutic strategies.

Prevalence of pulmonary hypertension in myelofibrosis

Pulmonary hypertension (PH) has been described in myelofibrosis (MF), but it is rare and typically found in advanced disease. Although the etiology of PH in MF is unclear, early predictors may be detected by echocardiogram. The goals of our study were to evaluate the prevalence of PH as determined by echocardiography in a cohort of MF patients and to identify clinical risk factors for PH. We performed a retrospective review of MF patients from October 2015 to May 2017 at MD Anderson Cancer Center in the ambulatory clinic, and those with echocardiogram were included. Clinical, echocardiographic, and laboratory data were reviewed. Patients with and without PH were compared using a chi-square or Fisher's exact test, and logistic regression was performed with an outcome variable of PH. There were 143 patients with MF who underwent echocardiogram, and 20 (14%) had echocardiographic findings consistent with PH. Older age, male gender, hypertension, hyperlipidemia, coronary artery disease, dyspnea, hematocrit, brain natriuretic peptide (BNP), and N-terminal prohormone BNP (NT-proBNP) were significantly different between those without PH and those with PH (p < 0.05). Female gender was protective (OR 0.21, 95% CI 0.049-0.90, p = 0.035), and NT-proBNP was a significant clinical predictor of PH (OR 1.07, CI 1.02 = 1.12, p = 0.006). PH in MF is lower than previously reported in our MF cohort, but many patients had cardiac comorbidities. PH due to left-sided heart disease may be underestimated in MF. Evaluation of respiratory symptoms and elevated NT-proBNP should prompt a baseline echocardiogram. Early detection of PH with a multidisciplinary approach may allow treatment of reversible etiologies.

Severe but reversible pulmonary hypertension in scleromyxedema and multiple myeloma: a case report

Background

Scleromyxedema is a progressive, systemic connective tissue disorder characterized by fibro-mucous skin lesions and increased serum monoclonal immunoglobulin levels. Pulmonary involvement occurs in a subset of patients, though the overall prevalence of pulmonary lesions in scleromyxedema is unknown. Since pulmonary hypertension presumably occurs in these patients due to disease progression and development of additional conditions, treatment of the underlying plasma cell dyscrasia and connective tissue disorder may improve pulmonary hypertension symptoms.

Case presentation

An elderly patient with scleromyxedema developed pulmonary hypertension refractory to vasodilator and diuretic therapy and subsequently multiple myeloma that responded to a combination therapy of bortezomib, cyclophosphamide, and dexamethasone treatment.

Conclusions

Treatment of the underlying disease(s) that contributed to pulmonary hypertension development with anti-neoplastic agents like bortezomib may improve cardiopulmonary symptoms secondary to reducing abnormal blood cell counts and paraprotein levels.

Pulmonary hypertension is associated with increased nonrelapse mortality after allogeneic hematopoietic cell transplantation for myelofibrosis

Allogeneic hematopoietic cell transplantation (alloHCT) is the only curative therapy for primary myelofibrosis (MF) as well as myelofibrosis secondary to other myeloproliferative neoplasms (MPN). Pulmonary hypertension (PH) is a known complication of MF and may occur in up to 50% of such patients. PH (defined as a mean pulmonary artery pressure ≥25 mmHg at rest) can eventually lead to right heart failure and may be associated with complications after alloHCT. We examined the association of PH with alloHCT outcome in patients with MF associated with MPN. Pre- and post-HCT echocardiograms were reviewed to estimate the peak pulmonary artery systolic pressure (PASP). Median PASP was 37.0 mmHg (range: 16.0-57.9) prior to HCT with 37 of 65 patients (57%) studied. With median follow-up of 35.0 months (range: 3.3-119.4) PH was significantly associated with inferior OS (58.9% vs. 88.8%, P = 0.025), primarily due to increased NRM (21.6% vs. 7.1%, P = 0.007). The majority of the deaths (8 of 14) in patients with PH occurred within 100 days after HCT. In patients with an available post-HCT echocardiogram (n = 33), the median PASP was 30 mmHg (range: 5.0-56.2); eight patients (24%) had persistent PH. Compared with pre-HCT values, PASP was significantly reduced after HCT (p < 0.001). We conclude that PH is associated with inferior survival due to the increased NRM in patients with MF undergoing alloHCT. PH appears at least partially reversible after successful alloHCT. PH should be considered a risk factor for early mortality after alloHCT and surveillance of pulmonary artery pressure in MF patients being considered for alloHCT may be useful.

Pulmonary hypertension in patients with myeloproliferative neoplasms: A large cohort of 183 patients

BACKGROUND

Chronic myeloproliferative neoplasms (MPN) are recognized as a cause of pulmonary hypertension (pH). We ought to describe the prevalence and characteristics of PH in a cohort of MPN who were screened using transthoracic echocardiography (TTE).

METHODS

One hundred eighty-three newly diagnosed consecutive MPN patients were prospectively evaluated using TTE to detect PH.

RESULTS

Two patients were diagnosed with chronic eosinophilic leukemia, two patients had post-essential thrombocythemia (ET) myelofibrosis (MF), two patients had post-polycythemia vera (PV) MF, 11 patients had primary myelofibrosis (PMF), 28 patients had chronic myeloid leukemia (CML), 51 patients had PV, and 87 patients had ET. TTE was used to determine PH, and PH was suspected in 16 of 183 patients as follows: four with PV, seven with ET, two with PMF, and three with CML. Two patients with ET were excluded because of global cardiac failure. Three patients underwent right heart catheterization to confirm PH. The 14 (7.7%) patients with PH had no cardiac or lung disease that directly involved MPN in PH development.

CONCLUSION

In this large cohort of 183 MPN patients, TTE was used to diagnose PH, and 14 patients (7.7%) developed PH. This prevalence was lower than expected based on previously reported data, but it remains higher than in the general population.

Prevalence and Effect on Survival of Pulmonary Hypertension in Myelofibrosis

BACKGROUND

Myelofibrosis (MF), a rare disorder characterized by bone marrow fibrosis, has been implicated as a cause of pulmonary hypertension (PH). To date, studies examining this association have not looked at the impact of PH on survival in MF. We examined the relationship between MF and PH by echocardiogram (echo) using a retrospective patient database and examined the influence of PH on overall survival.

PATIENTS AND METHODS

In this single-center retrospective chart review, we identified 65 patients with biopsy-proven primary and secondary MF, 31 of whom underwent transthoracic echo. After accounting for chronic obstructive pulmonary disease and left-sided or valvular heart dysfunction, which excluded 6 patients, we identified 14 patients (56%) who had echo evidence of group 5 PH (ie, PH due to unclear or multifactorial mechanisms), 8 with primary MF and 6 with secondary MF. MF patients with PH trended toward being predominantly female, being older, and less often having constitutional symptoms compared to the non-PH cohort.

RESULTS

There was no effect of the presence of PH on overall survival in the entire MF cohort or in any subgroup analyzed, including primary MF versus secondary MF and primary MF intermediate risk patients.

CONCLUSION

Given the high prevalence of MF-associated PH, there may be a larger role for routine echo screening in MF patients. Further, the underlying association between PH and MF may signify an endothelial plasticity or increased telomerase activity as part of the pathogenesis of MF.

Pulmonary hypertension with massive megalosplenia: A case report

RATIONALE

Pulmonary hypertension (PH) is a complicated disease which has complex causes and poor outcome. Many factors are involved in the increase of pulmonary artery pressure. It is often difficult to identify the specific cause of a particular patient. However, identifying the etiology is of great importance for specifying treatment strategies and improving the prognosis of patients.

PATIENT CONCERNS

A 58-year-old male was admitted because of fatigue, breath shortness for 6 months, which got worse in the last 3 months. The ultrasound cardiogram (UCG) indicated a remarkably elevated pulmonary artery systolic pressure (PASP = 82 mm Hg). He had hypertension for 15 years. Besides, his spleen was found to be enlarged since 15 years ago. Bone marrow biopsy of the patient revealed myeloproliferative neoplasm (MPN) with severe myelofibrosis (MF).

DIAGNOSIS

Myeloproliferative neoplasm (MPN) with severe myelofibrosis (MF) which in turn caused PH and portal vein hypertension (PVH).

INTERVENTIONS

We treated the patient with diuretics and fosinopril, and also steroids and thalidomide for his MPN/MF.

OUTCOMES

Two weeks later, the pulmonary artery pressure (PAP) was remarkably decreased (PASP = 53.1 mm Hg by UCG, mean PAP = 21 mm Hg by right cardiac catheterization). Within 2 years' follow-up, his circulatory state and hematological state remained stable.

LESSONS

It is often difficult to define the cause of PH, but it is important for making the appropriate treatment at the same time.

Hematopoietic stem cell transplantation alters susceptibility to pulmonary hypertension in Bmpr2-deficient mice

Increasing evidence suggests that patients with pulmonary arterial hypertension (PAH) demonstrate abnormalities in the bone marrow (BM) and hematopoietic progenitor cells. In addition, PAH is associated with myeloproliferative diseases. We have previously demonstrated that low-dose lipopolysaccharide (LPS) is a potent stimulus for the development of PAH in the context of a genetic PAH mouse model of BMPR2 dysfunction. We hypothesized that the hematopoietic progenitor cells might be driving disease in this model. To test this hypothesis, we performed adoptive transfer of BM between wild-type (Ctrl) and heterozygous Bmpr2 null (Mut) mice. Sixteen weeks after BM reconstitution, mice were exposed to low-dose chronic LPS (0.5 mg/kg three times a week for six weeks). Mice underwent right heart catheterization and tissues were removed for histology. After chronic LPS dosing, Ctrl mice in receipt of Mut BM developed PAH, whereas Mut mice receiving Ctrl BM were protected from PAH. BM histology demonstrated an increase in megakaryocytes and there was an increase in circulating platelets in Ctrl mice receiving Mut BM. These findings demonstrate that the hematopoietic stem cell compartment is involved in the susceptibility to PAH in the Mut mouse. The results raise the possibility that hematopoietic stem cell transplantation might be a potential treatment strategy in genetic forms of PAH.

Drug-induced pulmonary arterial hypertension: a review

Pulmonary arterial hypertension (PAH) is a subgroup of PH patients characterized hemodynamically by the presence of pre-capillary PH, defined by a pulmonary artery wedge pressure (PAWP) ≤15 mmHg and a PVR >3 Wood units (WU) in the absence of other causes of pre-capillary PH. According to the current classification, PAH can be associated with exposure to certain drugs or toxins such as anorectic agents, amphetamines, or selective serotonin reuptake inhibitors. With the improvement in awareness and recognition of the drug-induced PAH, it allowed the identification of additional drugs associated with an increased risk for the development of PAH. The supposed mechanism is an increase in the serotonin levels or activation of serotonin receptors that has been demonstrated to act as a growth factor for the pulmonary artery smooth muscle cells and cause progressive obliteration of the pulmonary vasculature. PAH remains a rare complication of several drugs, suggesting possible individual susceptibility, and further studies are needed to identify patients at risk of drug-induced PAH.

Medical Management of Pulmonary Hypertension with Unclear and/or Multifactorial Mechanisms (Group 5): Is There a Role for Pulmonary Arterial Hypertension Medications?

PURPOSE OF REVIEW

The purpose of this review was to outline the mechanisms and to review recent literature on pulmonary arterial hypertension (PAH) medications in group 5 pulmonary hypertension (PH).

RECENT FINDINGS

The first steps in management are to understand the mechanisms and hemodynamic profile and to exclude chronic thromboembolic disease. Recent studies in the past 5 years have found that PAH medications may improve hemodynamics in patients with pre-capillary pulmonary hypertension due to sarcoidosis, pulmonary Langerhans cell histiocytosis, lymphangioleiomyomatosis, and myeloproliferative disorders with dasatinib-induced PH. Improvements in exercise capacity are uncommon, and no survival benefit has been demonstrated. There is a risk of pulmonary edema in patients with pulmonary venous involvement or fibrosing mediastinitis when treated with PAH therapies. There is limited evidence supporting the use of PAH medications in group 5 patients, and they may be harmful in certain cases. In most patients with group 5 PH, treatment should be directed to the underlying disease with PAH therapies reserved for patients with severe pre-capillary PH.

Pulmonary Hypertension Associated with Pulmonary Veno-occlusive Disease in Patients with Polycythemia Vera

A 65-year-old man was diagnosed with polycythemia vera (PV) and treated with hydroxyurea. Three years later, he was admitted to our institution for severe hypoxia. Right heart catheterization revealed that the patient had pulmonary hypertension (PH). In addition, radiographic findings and resistance to pulmonary vasodilators led to the diagnosis of PH associated with pulmonary veno-occlusive disease. The administration of ruxolitinib improved his hematopoiesis and respiratory failure. While the disease is relatively common in Europe and the United States, limited data exist regarding myeloproliferative neoplasm complicated with PH in Japan. PH should be considered a potential complication and screened during the clinical care of patients with myeloproliferative neoplasms.

Hematological disorders and pulmonary hypertension

Pulmonary hypertension (PH), a serious disorder with a high morbidity and mortality rate, is known to occur in a number of unrelated systemic diseases. Several hematological disorders such as sickle cell disease, thalassemia and myeloproliferative diseases develop PH which worsens the prognosis. Associated oxidant injury and vascular inflammation cause endothelial damage and dysfunction. Pulmonary vascular endothelial damage/dysfunction is an early event in PH resulting in the loss of vascular reactivity, activation of proliferative and antiapoptotic pathways leading to vascular remodeling, elevated pulmonary artery pressure, right ventricular hypertrophy and premature death. Hemolysis observed in hematological disorders leads to free hemoglobin which rapidly scavenges nitric oxide (NO), limiting its bioavailability, and leading to endothelial dysfunction. In addition, hemolysis releases arginase into the circulation which converts L-arginine to ornithine, thus bypassing NO production. Furthermore, treatments for hematological disorders such as immunosuppressive therapy, splenectomy, bone marrow transplantation, and radiation have been shown to contribute to the development of PH. Recent studies have shown deregulated iron homeostasis in patients with cardiopulmonary diseases including pulmonary arterial hypertension (PAH). Several studies have reported low iron levels in patients with idiopathic PAH, and iron deficiency is an important risk factor. This article reviews PH associated with hematological disorders and its mechanism; and iron homeostasis and its relevance to PH.

Correlation between JAK2 allele burden and pulmonary arterial hypertension and hematological parameters in Philadelphia negative JAK2 positive myeloproliferative neoplasms. An Egyptian experience

Myeloproliferative neoplasms are characterized by a common stem cell-derived clonal proliferation, but are phenotypically diverse. JAK2 is mutated (V617F) in more than 90 % of patients with polycythemia vera (PV) and approximately 60 % of patients with essential thrombocythemia (ET) or primary myelofibrosis (PMF). Pulmonary arterial hypertension (PAH) is a major complication of several hematological disorders. Chronic myeloproliferative disorders associated with PAH have been included in group five for which the etiology is unclear and/or multifactorial. The aim of this study is to screen Egyptian Philadelphia negative JAK2 positive myeloproliferative neoplasm patients for the presence of PAH and its correlation with JAK2 allele burden. We also made a review for correlation of JAK2 allele with hematological parameters comparing our results to others. We enrolled 60 patients with Philadelphia negative myeloproliferative neoplasms. All patients enrolled in the study were subjected to laboratory and imaging workup in the form of CBC, liver, kidney profile, bone marrow examination, abdominal ultrasonography, and transthoracic echocardiography. Our results revealed that 7 patients out of 60 (11.67 %) had pulmonary arterial hypertension, 3 patients with PMF, 2 patients with PRV, and 2 patients with ET, and its correlation with JAK2 allele burden was not statistically significant. Correlation analysis between JAK2 V617F allele burden and other parameters revealed: statistical significant correlation with age, HB, HCT, PLT, UA, LDH, and splenic diameter but insignificant correlation with WBCs and PAH. Pulmonary arterial hypertension prevalence in our study was 11.67 % and no significant correlation with JAK 2 allele burden. Our study is the largest one up to our knowledge that studies the association between its prevalence and JAK2 burden.

Pulmonary hypertension in patients with chronic myeloproliferative disorders

Pulmonary hypertension (PH) is a major complication of several haematological disorders. Chronic myeloproliferative diseases (CMPDs) associated with pulmonary hypertension have been included in group five of the clinical classification for pulmonary hypertension, corresponding to pulmonary hypertension for which the aetiology is unclear and/or multifactorial. The aim of this review is to discuss the epidemiology, pathogenic mechanism and treatment approaches of the more common forms of pulmonary hypertension in the context of CMPD's: chronic thromboembolic pulmonary hypertension, precapillary pulmonary hypertension and drug-induced PH.

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.

World Health Organization group 5 pulmonary hypertension

World Health Organization (WHO) group 5 pulmonary hypertension (PH) entails a heterogeneous group of disorders that may cause PH by unclear and/or multiple mechanisms. In particular, group 5 includes PH caused by hematologic disorders, systemic diseases, metabolic disorders, chronic renal failure, and disorders leading to pulmonary vascular occlusion or compression. This article discusses common pathogenic mechanisms leading to group 5 PH, followed by a detailed overview of epidemiology, pathogenesis, and disease-specific management of the individual group 5 conditions. Off-label use of vasomodulatory therapies, typically indicated for pulmonary arterial hypertension (WHO group 1 PH), in group 5 conditions is also discussed.

Pulmonary hypertension associated with chronic hemolytic anemia and other blood disorders

Pulmonary hypertension (PH) has emerged as a major complication of several hematologic disorders, including hemoglobinopathies, red cell membrane disorders, chronic myeloproliferative disorders, and splenectomy. With the exception of sickle cell disease, there are a limited number of studies systematically evaluating the prevalence of PH using the gold standard right heart catheterization in these disorders. The cause of the PH in patients with hematologic disorders is multifactorial, and a thorough diagnostic evaluation is essential. More importantly, there are virtually no high-quality data on the safety and efficacy of PH-targeted therapy in this patient population.

Platelets in pulmonary vascular physiology and pathology

Almost a trillion platelets pass through the pulmonary circulation every minute, yet little is known about how they support pulmonary physiology or contribute to the pathogenesis of lung diseases. When considering this conundrum, three questions jump out: Does platelet production in the lungs occur? Why does severe thrombocytopenia—which undercuts the principal physiological role of platelets to effect hemostasis—not lead to pulmonary hemorrhage? Why does atherothrombosis—which platelets initiate, maintain, and trigger is other critically important arterial beds—not develop in the pulmonary artery? The purpose of this review is to explore these and derivative questions by providing data within a conceptual framework that begins to organize a subject that is largely unassembled.

Circulating and progenitor endothelial cells are abnormal in patients with different types of von Willebrand disease and correlate with markers of angiogenesis

von Willebrand disease (VWD) is the most common inherited bleeding disorder and is caused by quantitative or qualitative defects of von Willebrand factor (VWF). VWF, synthesized by endothelium and megakaryocytes (MK), circulates in plasma and is present in subendothelium and platelets. Circulating endothelial cells (CEC) and progenitor endothelial cells (EPC) have been recently proposed as markers of peripheral and bone marrow-derived angiogenesis. To evaluate the association of CEC/EPC with known inherited defects of cellular and circulating VWF, we have measured the number of CEC/EPC together with cytokines involved in angiogenesis in different VWD types. A group of 74 patients was composed by the following VWD types: VWD1 (n = 22), VWD2A (n = 9), VWD2B (n = 19), VWD2M (n = 17), and VWD3 (n = 7). Healthy individuals (n = 20) were used as controls. CEC (CD146(+) , CD31(+) , and CD45(-) ) and EPC (CD34(+) , CD133(+) , and CD45(-) ) were evaluated by flow cytometry. Circulating serum levels of VEGF, E-selectin, P-selectin, EPO, and TPO were determined by ELISA. CEC, VEGF, E-selectin, and EPO were higher and EPC lower in VWD patients than in controls (P < 0.01). Among the five groups of VWD patients and controls, a significant difference was found for CEC (one-way ANOVA: P = 0.005), EPC (P = 0.001), E-Selectin (P < 0.0001), EPO (P = 0.021), and TPO (P = 0.004): the latter was high in VWD3 patients. In VWD1, we found an inverse relationship between CEC and VWF:Ag levels (P = 0.048; R(2) = 0.19). Based on these data, CEC are increased in VWD and are associated with the high levels of cytokines involved in angiogenesis (up-regulation). EPC are decreased, suggesting down-regulation of bone marrow-derived angiogenesis in VWD.

The lung megakaryocytes and pulmonary fibrosis in systemic sclerosis

Systemic sclerosis (SSc) is an autoimmune connective tissue disease characterized by fibrotic changes in several organs including the lungs, skin, kidneys, muscles and the joints. The leading cause of death in SSc is pulmonary involvement consisting of pulmonary fibrosis with pulmonary hypertension. The pathogenesis of lung involvement in SSc is not yet clear though several mechanisms involving genetic, environmental, vascular, and immunological factors have been postulated. At the same time, the presence of megakaryocytes in the lungs is a less recognized concept and may also be contributing to lung fibrosis in SSc. These cells normally thought to be present only in the bone marrow have been demonstrated to be an important factor in the development of fibrosis of the bone marrow in the condition, idiopathic myelofibrosis. The article describes available evidence for the presence of lung megakaryocytes and hypothesizes that these cells are responsible for the development of pulmonary fibrosis in SSc based on the myelofibrosis model.