Characteristics and outcomes of gemcitabine-associated pulmonary hypertension.

Background: Despite its known cardiac and lung toxicities, the chemotherapy drug gemcitabine has only rarely been associated with pulmonary hypertension (PH), and the underlying mechanism remains unclear. The objective of the present study was to assess the association between gemcitabine and PH. Methods: We identified incident cases of precapillary PH confirmed by right heart catheterisation in patients treated with gemcitabine from the French PH Registry between January 2007 and December 2022. The aetiology, clinical, functional, radiological and haemodynamic characteristics of PH were reviewed at baseline and during follow-up. A pharmacovigilance disproportionality analysis was conducted using the World Health Organization (WHO) pharmacovigilance database. Results: We identified nine cases of pulmonary arterial hypertension, either induced (in eight patients) or exacerbated (in one patient) by gemcitabine. Patients exhibited severe precapillary PH, with a median mean pulmonary arterial pressure of 40 (range 26-47) mmHg, a cardiac index of 2.4 (1.6-3.9) L·min-1·m-2 and a pulmonary vascular resistance of 6.3 (3.1-12.6) Wood units. The median time from the initiation of gemcitabine to the onset of PH was 7 (4-50) months, with patients receiving a median of 16 (6-24) gemcitabine injections. Six patients showed clinical improvement upon discontinuation of gemcitabine. In the WHO pharmacovigilance database, we identified a significant signal with 109 cases reporting at least one adverse event related to PH with gemcitabine. Conclusion: Both clinical cases and pharmacovigilance data substantiate a significant association between gemcitabine use and the onset or worsening of precapillary PH. The observed improvement following the discontinuation of treatment underscores the importance of PH screening in gemcitabine-exposed patients experiencing unexplained dyspnoea.

Comparative Effectiveness of Sotatercept and Approved Add-On Pulmonary Arterial Hypertension Therapies: A Systematic Review and Network Meta-Analysis.

RATIONALE: There are no direct comparisons of sotatercept to add-on therapies approved for PAH. OBJECTIVE: This study aimed to compare the efficacy and safety of add-on sotatercept versus other add-on therapies using a network meta-analysis. METHODS: We searched MEDLINE, Embase, the Cochrane CENTRAL, and Clinicaltrials.gov until April 15, 2023, for randomized trials involving PAH patients treated with add-on sotatercept or add-on other PAH therapies. Data extraction and risk of bias assessments were performed independently and in duplicate using the Cochrane RoB 2.0 tool. We performed frequentist random-effects network meta-analysis using the restricted maximum likelihood (REML) estimator and assessed the certainty of evidence using the GRADE approach. RESULTS: Our search found 18 trials (5777 patients) eligible for analysis. Sotatercept reduces clinical worsening as compared to placebo (RR 0.21 [95% CI 0.11 to 0.41]; high certainty). Sotatercept probably reduces clinical worsening more compared to add-on ERA (RR 0.28 [95% CI 0.14 to 0.55]), prostanoid (Inh) (RR 0.21 [95% CI 0.07 to 0.67]), and prostanoid (PO) (RR 0.32 [95% CI 0.16 to 0.67]) (all moderate certainty). Sotatercept probably improves 6MWD as compared to placebo (MD 36.89m [95% CI 25.26 to 48.51]). Although sotatercept probably improves 6MWD more than add-on ERA (MD 18.38m [95% CI 5.92 to 30.84]) and prostanoid (PO) (MD 25.66m [95% CI 13.71 to 37.61]), it did not exceed the MCID of 33m (both moderate certainty). CONCLUSION: Sotatercept is an effective add-on therapy for PAH, likely superior to many approved add-on PAH therapies in reducing clinical worsening.

Characteristics and outcomes of patients developing pulmonary hypertension associated with proteasome inhibitors.

RATIONALE: Pulmonary arterial hypertension (PAH) has been described in patients treated with proteasome inhibitors (PI). OBJECTIVES: To evaluate the association between PI and PAH. METHODS: Characteristics of incident PAH cases previously treated with Carfilzomib or Bortezomib were analyzed from the French PH Registry and the VIGIAPATH program from 2004 to 2023, concurrently with a pharmacovigilance disproportionality analysis using the WHO's global database, and a meta-analysis of randomized controlled trials. RESULTS: Eleven incident cases of PI associated PAH were identified (6 with Carfilzomib and 5 with Bortezomib) with a female: male ratio of 2.7:1, a median age of 61 years, and a median delay between PI first exposure and PAH of 6 months. Four patients died (2 from right heart failure, 1 from respiratory distress, and 1 from an unknown cause). At diagnosis, 6 were in NYHA-Fc III/IV with severe hemodynamic impairment (median mean pulmonary artery pressure of 39 mmHg, cardiac index 2.45 L/min·m-2, and pulmonary vascular resistance of 7.2 WU). In the WHO pharmacovigilance database, 166 cases of PH associated with PI were reported since 2013 with significant statistics of disproportionate reporting (SDR) for Carfilzomib, regardless of the definition of cases or control group. However, SDR for Bortezomib was inconsistent. The systematic review identified 17 clinical trials, and Carfilzomib was associated with a significantly higher risk of dyspnea, severe dyspnea and PH compared to Bortezomib. CONCLUSION: PI may induce PAH in patients undergoing treatment, with Carfilzomib emitting a stronger signal than Bortezomib, and these patients should be monitored closely.

Dietary intake and glutamine-serine metabolism control pathologic vascular stiffness.

Perivascular collagen deposition by activated fibroblasts promotes vascular stiffening and drives cardiovascular diseases such as pulmonary hypertension (PH). Whether and how vascular fibroblasts rewire their metabolism to sustain collagen biosynthesis remains unknown. Here, we found that inflammation, hypoxia, and mechanical stress converge on activating the transcriptional coactivators YAP and TAZ (WWTR1) in pulmonary arterial adventitial fibroblasts (PAAFs). Consequently, YAP and TAZ drive glutamine and serine catabolism to sustain proline and glycine anabolism and promote collagen biosynthesis. Pharmacologic or dietary intervention on proline and glycine anabolic demand decreases vascular stiffening and improves cardiovascular function in PH rodent models. By identifying the limiting metabolic pathways for vascular collagen biosynthesis, our findings provide guidance for incorporating metabolic and dietary interventions for treating cardiopulmonary vascular disease.

Risk stratification refinements with inclusion of haemodynamic variables at follow-up in patients with pulmonary arterial hypertension.

BACKGROUND AND AIMS: Haemodynamic variables are prognostic factors in pulmonary arterial hypertension (PAH). However, right heart catheterization (RHC) is not systematically recommended to assess the risk-status during follow-up. This study aimed to assess the added value of haemodynamic variables in prevalent patients to predict the risk of death or lung transplantation according to their risk status assessed by the non-invasive 4 strata model as recommended by the European guidelines. METHODS: We evaluated incident patients with PAH enrolled in the French PAH Registry between 2009 and 2020 who had a first follow-up RHC. Cox regression identified, in each follow-up risk status, haemodynamic variables significantly associated with transplant-free survival (TFS). Optimal thresholds were determined by time-dependent Receiver-Operating Characteristics. Several multivariable Cox regression models were performed to identify the haemodynamic variables improving the non-invasive risk stratification model. RESULTS: We analysed 1240 incident patients reassessed within a year by RHC. None of haemodynamic variable were significantly associated with TFS among low-risk (n=386) or high-risk (n=71) patients. Among patients at intermediate (-low, n=483, -high, n=300) risk at first follow-up, multivariable models including either stroke volume index (SVi) or mixed venous oxygen saturation (SvO2) were the best. The prognostic performance of refined 6 strata risk stratification model including the non-invasive 4 strata model and SVi>37 mL·m-2 and/or SvO2>65% for patients at intermediate-risk (Area Under the Curve 0.81, c-index 0.74), was better than that of 4 strata model (0.79, p=0.009; c-index 0.72). CONCLUSIONS: Cardiopulmonary haemodynamics may improve risk stratification at follow-up in patients at intermediate-risk.

A study of ChatGPT in facilitating Heart Team decisions on severe aortic stenosis.

BACKGROUND: Multidisciplinary Heart Teams (HTs) play a central role in the management of valvular heart diseases. However, the comprehensive evaluation of patients' data can be hindered by logistical challenges, which in turn may affect the care they receive. AIMS: This study aimed to explore the ability of artificial intelligence (AI), particularly large language models (LLMs), to improve clinical decision-making and enhance the efficiency of HTs. METHODS: Data from patients with severe aortic stenosis presented at HT meetings were retrospectively analysed. A standardised multiple-choice questionnaire, with 14 key variables, was processed by the OpenAI Chat Generative Pre-trained Transformer (GPT)-4. AI-generated decisions were then compared to those made by the HT. RESULTS: This study included 150 patients, with ChatGPT agreeing with the HT's decisions 77% of the time. The agreement rate varied depending on treatment modality: 90% for transcatheter valve implantation, 65% for surgical valve replacement, and 65% for medical treatment. CONCLUSIONS: The use of LLMs offers promising opportunities to improve the HT decision-making process. This study showed that ChatGPT's decisions were consistent with those of the HT in a large proportion of cases. This technology could serve as a failsafe, highlighting potential areas of discrepancy when its decisions diverge from those of the HT. Further research is necessary to solidify our understanding of how AI can be integrated to enhance the decision-making processes of HTs.

Disrupted BMP-9 Signaling Impairs Pulmonary Vascular Integrity in Hepatopulmonary Syndrome.

RATIONALE: Hepatopulmonary syndrome (HPS) is a severe complication of liver diseases characterized by abnormal dilatation of pulmonary vessels, resulting in impaired oxygenation. Recent research highlights the pivotal role of liver-produced bone morphogenetic protein (BMP)-9 in maintaining pulmonary vascular integrity. OBJECTIVES: This study aimed to investigate the involvement of BMP-9 in human and experimental HPS. METHODS: Circulating BMP-9 levels were measured in 63 healthy controls and 203 cirrhotic patients, with or without HPS. Two animal models of portal hypertension were employed: common bile duct ligation (CBDL) with cirrhosis and long-term partial portal vein ligation (PPVL) without cirrhosis. Additionally, the therapeutic effect of low-dose BMP activator FK506 was investigated, and the pulmonary vascular phenotype of BMP-9 knockout rats was analyzed. MEASUREMENTS AND MAIN RESULTS: Patients with HPS related to compensated cirrhosis demonstrated lower levels of circulating BMP-9 compared to patients without HPS. Severe cirrhosis patients exhibited consistently low levels of BMP-9. In animal models, HPS characteristics, including intrapulmonary vascular dilations (IPVDs) and alveolo-arterial gradient enlargement, were observed. HPS development in both rat models correlated with reduced intrahepatic BMP-9 expression, decreased circulating BMP-9 level and activity, and impaired pulmonary BMP-9 endothelial pathway. Daily treatment with FK506 for 2-weeks restored BMP pathway in the lungs, alleviating IPVDs, and improving gas exchange impairment. Furthermore, BMP-9 knockout rats displayed a pulmonary HPS phenotype, supporting its role in disease progression. CONCLUSION: The study findings suggest that portal hypertension-induced loss of BMP-9 signaling contributes to HPS development.

Updated Clinical Classification and Hemodynamic Definitions of Pulmonary Hypertension and Its Clinical Implications.

Pulmonary hypertension (PH) refers to a pathologic elevation of the mean pulmonary artery pressure (mPAP) and is associated with increased morbidity and mortality in a wide range of medical conditions. These conditions are classified according to similarities in pathophysiology and management in addition to their invasive hemodynamic profiles. The 2022 ESC/ERS guidelines for the diagnosis and treatment of pulmonary hypertension present the newest clinical classification system and includes significant updates to the hemodynamic definitions. Pulmonary hypertension is now hemodynamically defined as an mPAP > 20 mmHg, reduced from the previous threshold of ≥25 mmHg, due to important insights from both normative and prognostic data. Pulmonary vascular resistance has been extended into the definition of pre-capillary pulmonary hypertension, with an updated threshold of >2 Wood Units (WU), to help differentiate pulmonary vascular disease from other causes of increased mPAP. Exercise pulmonary hypertension has been reintroduced into the hemodynamic definitions and is defined by an mPAP/cardiac output slope of >3 mmHg/L/min between rest and exercise. While these new hemodynamic thresholds will have a significant impact on the diagnosis of pulmonary hypertension, no evidence-based treatments are available for patients with mPAP between 21-24 mmHg and/or PVR between 2-3 WU or with exercise PH. This review highlights the evidence underlying these major changes and their implications on the diagnosis and management of patients with pulmonary hypertension.

Role of KCNK3 Dysfunction in Dasatinib-associated PAH and Endothelial Cell Dysfunction.

Pulmonary arterial hypertension (PAH) is severe cardiopulmonary disease that may be triggered by exposure to drugs such as dasatinib or facilitated by genetic predispositions. The incidence of dasatinib-associated PAH is estimated at 0.45%, suggesting individual predispositions. The mechanisms of dasatinib-associated PAH are still incomplete. We discovered a KCNK3 gene (coding for outward K+ channel) variant in a patient with dasatinib-associated PAH, and we investigated the impact of this variant on KCNK3 function. Additionally, we assessed the effects of dasatinib exposure on KCNK3 expression. In control-human in pulmonary arterial smooth muscle cells (hPASMCs) and pulmonary endothelial cells (hPECs), we evaluated the consequence of KCNK3 knockdown on cell migration, mitochondrial membrane potential, ATP production, and in vitro tube formation. Using mass spectrometry, we determined the KCNK3 interactome. Patch-clamp revealed that the KCNK3 variant represents a loss-of-function variant. Dasatinib contributed to pulmonary artery constriction by decreasing KCNK3 function and expression. In control-hPASMCs, KCNK3 knockdown promotes mitochondrial membrane depolarization and glycolytic shift. Dasatinib exposure or KCNK3 knockdown reduced the number of caveolae in hPECs. Moreover, KCNK3 knockdown in control-hPECs reduced migration, proliferation, and in vitro tubulogenesis. Using proximity labeling and mass spectrometry, we identified the KCNK3 interactome, revealing that KCNK3 interacts with various proteins across different cellular compartments. We identified a novel pathogenic variant in the KCNK3 and showed that dasatinib downregulates KCNK3, emphasizing the relationship between dasatinib-associated PAH and KCNK3 dysfunction. We demonstrated that loss of KCNK3-dependent signaling contributes to endothelial dysfunction in PAH and glycolytic switch of hPASMCs.

IMPAHCT: A randomized phase 2b/3 study of inhaled imatinib for pulmonary arterial hypertension.

AV-101 (imatinib) powder for inhalation, an investigational dry powder inhaled formulation of imatinib designed to target the underlying pathobiology of pulmonary arterial hypertension, was generally well tolerated in healthy adults in a phase 1 single and multiple ascending dose study. Inhaled Imatinib Pulmonary Arterial Hypertension Clinical Trial (IMPAHCT; NCT05036135) is a phase 2b/3, randomized, double-blind, placebo-controlled, dose-ranging, and confirmatory study. IMPAHCT is designed to identify an optimal AV-101 dose (phase 2b primary endpoint: pulmonary vascular resistance) and assess the efficacy (phase 3 primary endpoint: 6-min walk distance), safety, and tolerability of AV-101 dose levels in subjects with pulmonary arterial hypertension using background therapies. The study has an operationally seamless, adaptive design allowing for continuous recruitment. It includes three parts; subjects enrolled in Part 1 (phase 2b dose-response portion) or Part 2 (phase 3 intermediate portion) will be randomized 1:1:1:1 to 10, 35, 70 mg AV-101, or placebo (twice daily), respectively. Subjects enrolled in Part 3 (phase 3 optimal dose portion) will be randomized 1:1 to the optimal dose of AV-101 and placebo (twice daily), respectively. All study parts include a screening period, a 24-week treatment period, and a 30-day safety follow-up period; the total duration is ∼32 weeks. Participation is possible in only one study part. IMPAHCT has the potential to advance therapies for patients with pulmonary arterial hypertension by assessing the efficacy and safety of a novel investigational drug-device combination (AV-101) using an improved study design that has the potential to save 6-12 months of development time. ClinicalTrials.gov Identifier: NCT05036135.

Pulmonary vascular phenotype identified in patients with GDF2 (BMP9) or BMP10 variants: an international multicentre study.

BACKGROUND: Bone morphogenetic proteins 9 and 10 (BMP9 and BMP10), encoded by GDF2 and BMP10, respectively, play a pivotal role in pulmonary vascular regulation. GDF2 variants have been reported in pulmonary arterial hypertension (PAH) and hereditary haemorrhagic telangiectasia (HHT). However, the phenotype of GDF2 and BMP10 carriers remains largely unexplored. METHODS: We report the characteristics and outcomes of PAH patients in GDF2 and BMP10 carriers from the French and Dutch pulmonary hypertension registries. A literature review explored the phenotypic spectrum of these patients. RESULTS: 26 PAH patients were identified: 20 harbouring heterozygous GDF2 variants, one homozygous GDF2 variant, four heterozygous BMP10 variants, and one with both GDF2 and BMP10 variants. The prevalence of GDF2 and BMP10 variants was 1.3% and 0.4%, respectively. Median age at PAH diagnosis was 30 years, with a female/male ratio of 1.9. Congenital heart disease (CHD) was present in 15.4% of the patients. At diagnosis, most of the patients (61.5%) were in New York Heart Association Functional Class III or IV with severe haemodynamic compromise (median (range) pulmonary vascular resistance 9.0 (3.3-40.6) WU). Haemoptysis was reported in four patients; none met the HHT criteria. Two patients carrying BMP10 variants underwent lung transplantation, revealing typical PAH histopathology. The literature analysis showed that 7.6% of GDF2 carriers developed isolated HHT, and identified cardiomyopathy and developmental disorders in BMP10 carriers. CONCLUSIONS: GDF2 and BMP10 pathogenic variants are rare among PAH patients, and occasionally associated with CHD. HHT cases among GDF2 carriers are limited according to the literature. BMP10 full phenotypic ramifications warrant further investigation.

Pulmonary Hypertension in Connective Tissue Diseases Other than Systemic Sclerosis.

Pulmonary hypertension (PH) is a known complication of certain connective tissue diseases (CTDs), with systemic sclerosis (SSc) being the most common in the Western world. However, PH in association with non-SSc CTD such as systemic lupus erythematous, mixed connective tissue disease, and primary Sjögren's syndrome constitutes a distinct subset of patients with inherently different epidemiologic profiles, pathophysiologic mechanisms, clinical features, therapeutic options, and prognostic implications. The purpose of this review is to inform a practical approach for clinicians evaluating patients with non-SSc CTD-associated PH.The development of PH in these patients involves a complex interplay between genetic factors, immune-mediated mechanisms, and endothelial cell dysfunction. Furthermore, the broad spectrum of CTD manifestations can contribute to the development of PH through various pathophysiologic mechanisms, including intrinsic pulmonary arteriolar vasculopathy (pulmonary arterial hypertension, Group 1 PH), left-heart disease (Group 2), chronic lung disease (Group 3), chronic pulmonary artery obstruction (Group 4), and unclear and/or multifactorial mechanisms (Group 5). The importance of diagnosing PH early in symptomatic patients with non-SSc CTD is highlighted, with a review of the relevant biomarkers, imaging, and diagnostic procedures required to establish a diagnosis.Therapeutic strategies for non-SSc PH associated with CTD are explored with an in-depth review of the medical, interventional, and surgical options available to these patients, emphasizing the CTD-specific considerations that guide treatment and aid in prognosis. By identifying gaps in the current literature, we offer insights into future research priorities that may prove valuable for patients with PH associated with non-SSc CTD.

4D flow cardiac MRI to assess pulmonary blood flow in patients with pulmonary arterial hypertension associated with congenital heart disease.

PURPOSE: The purpose of this study was to evaluate the accuracy of four-dimensional flow cardiac magnetic resonance imaging (4D flow MRI) compared to right heart catheterization in measuring pulmonary flow (Qp), systemic flow (Qs) and pulmonary-to-systemic flow ratio (Qp/Qs) in patients with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD). MATERIALS AND METHODS: The study was registered on Clinical-trial.gov (NCT03928002). Sixty-four patients with PAH-CHD who underwent 4D flow MRI were included. There were 16 men and 48 women with a mean age of 45.3 ± 13.7 (standard deviation [SD]) years (age range: 21-77 years). Fifty patients (50/64; 78%) presented with pre-tricuspid shunt. Qp (L/min), Qs (L/min) and Qp/Qs were measured invasively using direct Fick method during right heart catheterization and compared with measurements assessed by 4D flow MRI within a 24-48-hour window. RESULTS: The average mean pulmonary artery pressure was 51 ± 17 (SD) mm Hg with median pulmonary vascular resistance of 8.8 Wood units (Q1, Q3: 5.3, 11.7). A strong linear correlation was found between Qp measurements obtained with 4D flow MRI and those obtained with the Fick method (r = 0.96; P < 0.001). Bland Altman analysis indicated a mean difference of 0.15 ± 0.48 (SD) L/min between Qp estimated by 4D flow MRI and by right heart catheterization. A strong correlation was found between Qs and Qp/Qs measured by 4D flow MRI and those obtained with the direct Fick method (r = 0.85 and r = 0.92; P < 0.001 for both). CONCLUSION: Qp as measured by 4D flow MRI shows a strong correlation with measurements derived from the direct Fick method. Further investigation is needed to develop less complex and standardized methods for measuring essential PAH parameters, such as pulmonary arterial pressures and pulmonary vascular resistance.

Allele-specific control of rodent and human lncRNA KMT2E-AS1 promotes hypoxic endothelial pathology in pulmonary hypertension.

Hypoxic reprogramming of vasculature relies on genetic, epigenetic, and metabolic circuitry, but the control points are unknown. In pulmonary arterial hypertension (PAH), a disease driven by hypoxia inducible factor (HIF)-dependent vascular dysfunction, HIF-2α promoted expression of neighboring genes, long noncoding RNA (lncRNA) histone lysine N-methyltransferase 2E-antisense 1 (KMT2E-AS1) and histone lysine N-methyltransferase 2E (KMT2E). KMT2E-AS1 stabilized KMT2E protein to increase epigenetic histone 3 lysine 4 trimethylation (H3K4me3), driving HIF-2α-dependent metabolic and pathogenic endothelial activity. This lncRNA axis also increased HIF-2α expression across epigenetic, transcriptional, and posttranscriptional contexts, thus promoting a positive feedback loop to further augment HIF-2α activity. We identified a genetic association between rs73184087, a single-nucleotide variant (SNV) within a KMT2E intron, and disease risk in PAH discovery and replication patient cohorts and in a global meta-analysis. This SNV displayed allele (G)-specific association with HIF-2α, engaged in long-range chromatin interactions, and induced the lncRNA-KMT2E tandem in hypoxic (G/G) cells. In vivo, KMT2E-AS1 deficiency protected against PAH in mice, as did pharmacologic inhibition of histone methylation in rats. Conversely, forced lncRNA expression promoted more severe PH. Thus, the KMT2E-AS1/KMT2E pair orchestrates across convergent multi-ome landscapes to mediate HIF-2α pathobiology and represents a key clinical target in pulmonary hypertension.