LRP1 Repression by SNAIL Results in ECM Remodeling in Genetic Risk for Vascular Diseases.

BACKGROUND: Genome-wide association studies implicate common genetic variations in the LRP1 (low-density lipoprotein receptor-related protein 1) locus at risk for multiple vascular diseases and traits. However, the underlying biological mechanisms are unknown. METHODS: Fine mapping analyses included Bayesian colocalization to identify the most likely causal variant. Human induced pluripotent stem cells were genome-edited using CRISPR-Cas9 to delete or modify candidate enhancer regions and generate LRP1 knockout cell lines. Cells were differentiated into smooth muscle cells through a mesodermal lineage. Transcription regulation was assessed using luciferase reporter assay, transcription factor knockdown, and chromatin immunoprecipitation. Phenotype changes in cells were conducted using cellular assays, bulk RNA sequencing, and mass spectrometry. RESULTS: Multitrait colocalization analyses pointed at rs11172113 as the most likely causal variant in LRP1 for fibromuscular dysplasia, migraine, pulse pressure, and pulmonary function trait. We found the rs11172113-T allele to associate with higher LRP1 expression. Genomic deletion in induced pluripotent stem cell-derived smooth muscle cells supported rs11172113 to locate in an enhancer region regulating LRP1 expression. We found transcription factors MECP2 (methyl CpG binding protein 2) and SNAIL to repress LRP1 expression through an allele-specific mechanism, involving SNAIL interaction with disease risk allele. LRP1 knockout decreased induced pluripotent stem cell-derived smooth muscle cell proliferation and migration. Differentially expressed genes were enriched for collagen-containing extracellular matrix, connective tissue development, and lung development. LRP1 knockout and deletion of rs11172113 enhancer showed potentiated canonical TGF-ß (transforming growth factor beta) signaling through enhanced phosphorylation of SMAD2/3. Analyses of the protein content of decellularized extracts indicated partial extracellular matrix remodeling involving enhanced secretion of CYR61, a known LRP1 ligand involved in vascular integrity and TIMP3, implicated in extracellular matrix maintenance and also known to interact with LRP1. CONCLUSIONS: Our findings support allele-specific LRP1 gene repression by the endothelial-to-mesenchymal transition regulator SNAIL. We propose decreased LRP1 expression in smooth muscle cells to remodel the extracellular matrix enhanced by TGF-ß as a potential mechanism of this pleiotropic locus for vascular diseases.

lncRNA VELRP Modulates Pulmonary Arterial Smooth Muscle Cell Proliferation and Promotes Vascular Remodeling in Pulmonary Hypertension.

BACKGROUND: Pulmonary hypertension is a devastating vascular disorder characterized by extensive pulmonary vascular remodeling, ultimately leading to right ventricular failure and death. Activation of PDGF (platelet-derived growth factor) signaling promotes the hyperproliferation of pulmonary arterial smooth muscle cells (PASMCs), thus contributing to the pulmonary vascular remodeling. However, the molecular mechanisms that govern hyperproliferation of PASMCs induced by PDGF remain largely unknown, including the contribution of long noncoding RNAs (lncRNAs). In this study, we aimed to identify a novel lncRNA regulated by PDGF implicated in PASMC proliferation in pulmonary vascular remodeling. METHODS: RNA-sequencing analysis was conducted to identify a novel lncRNA named vessel-enriched lncRNA regulated by PDGF-BB (VELRP). Functional investigations of VELRP were performed using knockdown and overexpression strategies along with RNA sequencing. Validation of the function and potential mechanisms of VELRP were performed through Western blot, RNA immunoprecipitation, and chromatin immunoprecipitation assays. RESULTS: We identified a novel vessel-enriched lncRNA with an increased response to PDGF-BB stimulus. VELRP was identified as an evolutionarily conserved RNA molecules. Modulation of VELRP in PASMCs significantly altered cell proliferation. Mechanistically, VELRP enhances trimethylation of H3K4 by interacting with WDR5 (WD repeat-containing protein 5), leading to increased expression of CDK (cyclin-dependent kinase) 1, CDK2, and CDK4 and consequent hyperproliferation of PASMCs. The pathological relevance of VELRP upregulation in pulmonary artery was confirmed using rat pulmonary hypertension models in vivo, as well as in PASMCs from patients with idiopathic pulmonary arterial hypertension patients. Specific knockdown of VELRP in smooth muscle cells using adeno-associated virus type 9 SM22α (smooth muscle protein 22α) promoter-shRNA-mediated silencing of VELRP resulted in a significant decrease in right ventricular systolic pressure and vascular remodeling in rat pulmonary hypertension model. CONCLUSIONS: VELRP, as an lncRNA upregulated by PDGF-BB, mediates PASMC proliferation via WDR5/CDK signaling. In vivo studies demonstrate that targeted intervention of VELRP in smooth muscle cells can prevent the development of pulmonary hypertension.

Prognostic Value of Pulmonary Artery Systolic Pressure in Severe Rheumatic Mitral Stenosis.

BACKGROUND: Current guidelines recommend intervention for asymptomatic rheumatic mitral stenosis (MS) with mitral valve area ≤1.5 cm2 based on indicators including pulmonary arterial systolic pressure (PASP) >50 mm Hg and new-onset atrial fibrillation; however, evidence supporting this is lacking. METHODS: This single-center retrospective study included patients with rheumatic MS between 2006 and 2022. Pulmonary hypertension was evaluated by using echocardiography to estimate PASP. Primary outcomes were major adverse cardiovascular events (MACE), including all-cause mortality, hospitalization for heart failure, and arterial thromboembolic events for up to 5 years. RESULTS: Overall, 287 patients with severe rheumatic MS were enrolled (mean age, 62.5±11.3 years; 74.6% women). During a median follow-up of 2.52 years, MACE occurred in 99 patients. There were no differences in echocardiographic parameters, such as the mean mitral valve pressure gradient, mitral valve area, and proportion of mitral valve area <1.0 cm2, between patients who developed primary outcomes and those who did not. Survival analysis showed a worse prognosis in patients with estimated PASP (ePASP) >50 mm Hg than in those with ePASP ≤50 mm Hg (log-rank P<0.001); however, atrial fibrillation was not a significant prognostic indicator. As a continuous variable, ePASP (mm Hg) was a significant predictor of MACE (adjusted hazard ratio, 1.027 [95% CI, 1.011-1.042]; P<0.001). Receiver operating characteristic analysis revealed an optimal ePASP threshold of >45 mm Hg, which was an independent predictor of MACE in patients with severe rheumatic MS (adjusted hazard ratio, 2.127 [95% CI, 1.424-3.177]; P<0.001). Competing risk analysis considering mitral valve intervention as a competing risk showed similar results. CONCLUSIONS: Our study demonstrated the prognostic significance of ePASP, rather than atrial fibrillation, in relation to MACE among patients with severe rheumatic MS. Additionally, we proposed a lower ePASP threshold (>45 mm Hg) as a predictor of an unfavorable prognosis.

[Iron deficiency in cardiovascular disease]. / Eisenmangel bei kardiovaskulären Erkrankungen.

BACKGROUND: Iron deficiency is worldwide the most frequently occurring deficiency of a trace element. Meanwhile, the indications are increasing that iron deficiency plays a relevant role in many cardiovascular diseases and that treatment is accessible with intravenous administration of iron. OBJECTIVE AND METHODS: The aim of this article is to elucidate the clinical comorbidities, diagnostic dilemmas and treatment possibilities of iron deficiency in cardiovascular diseases. The study situation on iron deficiency and iron substitution in heart failure, aortic valve stenosis, atrial fibrillation and pulmonary hypertension (PH) is summarized. RESULTS: The diagnostic criteria of iron deficiency in cardiovascular diseases are not finally decided. The guidelines of the European Society of Cardiology recommend either ferritin below 100 ng/ml alone or ferritin between 100 and 299 ng/ml with a transferrin saturation (TSAT) < 20 %. Some authors consider the determination of TSAT as sufficient as the only diagnostic criterion for iron deficiency in heart failure. Most studies on iron substitution in heart failure showed an improvement in the physical capacity and a reduction of the probability of a heart failure-related hospitalization by the substitution of an existing iron deficiency; however, it has been determined that a relevant proportion of patients show no response to iron substitution and that the cause for this is ultimately unclear. Whether the diagnostic criteria for iron deficiency in heart failure can be transferred to other cardiovascular symptoms, cannot be clearly answered due to the lack of data from prospective interventional studies. CONCLUSION: The substitution of iron deficiency is one of very few possibilities to improve the physical capability in heart failure. The pivotal point of the discussion on iron deficiency and substitution in cardiovascular diseases is the correct identification of patients who benefit from treatment.

Worldwide CTEPH Registry: Long-Term Outcomes With Pulmonary Endarterectomy, Balloon Pulmonary Angioplasty, and Medical Therapy.

BACKGROUND: The European Chronic Thromboembolic Pulmonary Hypertension registry (CTEPH), conducted between 2007 and 2012, reported the major impact of pulmonary endarterectomy (PEA) on the long-term survival of patients with CTEPH. Since then, 2 additional treatments for inoperable CTEPH have become available: balloon pulmonary angioplasty (BPA), and an approved oral drug therapy with the guanylate cyclase stimulator riociguat. The current registry aimed to evaluate the effect of these new therapeutic approaches in a worldwide context. METHODS: Participation in this international global registry included 34 centers in 20 countries. Between February 2015 and September 2016, 1009 newly diagnosed, consecutive patients were included and followed until September 2019. RESULTS: Overall, 605 patients (60%) underwent PEA and 185 (18%) underwent BPA; 76% of the 219 remaining patients not receiving mechanical intervention (ie, neither PEA nor BPA) were treated with pulmonary hypertension drugs. Oof patients undergoing PEA and BPA, 38% and 78% also received drugs for pulmonary hypertension, respectively. Median age at diagnosis was higher in the BPA and No PEA/BPA groups than in the PEA group: 66 and 69, respectively, versus 60 years. Pulmonary vascular resistance (PVR) was similar in all groups, with an average of 643 dynes/(s·cm-5). During an observation period (>3 years; ≤5.6 years), death was reported in 7%, 11%, and 27% of patients treated by PEA and BPA, and those receiving no mechanical intervention (P<0.001). In Kaplan-Meier analysis, 3-year survival was 94%, 92%, and 71% in the 3 groups, respectively. PEA 3-year survival improved by 5% from that observed between 2007 and 2012. There was no survival difference in patients receiving vitamin K antagonists and non-vitamin K oral anticoagulants (P=0.756). In Cox regression, reduced mortality was associated with: PEA and BPA in the global cohort; history of venous thromboembolism and lower PVR in the PEA group; lower right atrial pressure in the BPA group; and use of pulmonary hypertension drugs, oxygen therapy, and lower right atrial pressure, as well as functional class in the group receiving no mechanical intervention. CONCLUSIONS: This second international CTEPH registry reveals important improvement in patient survival since the introduction of BPA and an approved drug for pulmonary hypertension. The type of anticoagulation regimen did not influence survival. REGISTRATION: URL https://clinicaltrials.gov; Unique identifier: NCT02656238.

Hypercapnia during transcatheter aortic valve replacement under monitored anaesthesia care: a retrospective cohort study.

BACKGROUND: Acute intraoperative hypercapnia and respiratory acidosis, which can occur during monitored anaesthesia care (MAC), pose significant cardiopulmonary risks for patients with aortic stenosis undergoing transcatheter aortic valve replacement (TAVR). The goal of the present study is to assess the incidence, risk factors and impact of intraoperative hypercapnia during MAC for patients undergoing transfemoral TAVR. METHODS: Data was collected retrospectively from the electronic medical record of 201 consecutive patients with available intraoperative arterial blood gas (ABG) data who underwent percutaneous transfemoral TAVR with MAC using propofol and dexmedetomidine. ABGs (pH, arterial partial pressure of carbon dioxide (PaCO2) and arterial partial pressure of oxygen) were performed at the start of each case (baseline), immediately prior to valve deployment (ValveDepl), and on arrival to the postanaesthesia care unit. Data was analysed using Fisher's exact test, unpaired Student's t-test, Wilcoxon rank sum or univariate linear regression as appropriate based on PaCO2 and pH during ValveDepl (PaCO2-ValveDepl, pH-ValveDepl) and change in PaCO2 and pH from baseline to ValveDepl (PaCO2-%increase, pH-%decrease) to determine their association with preoperative demographic data, intraoperative anaesthetic and vasoactive medications and postoperative outcomes. RESULTS: PaCO2 increased by a mean of 28.4% and was higher than baseline in 91% of patients. Younger age, male sex, increased weight and increased propofol dose contributed to higher PaCO2-ValveDepl and greater PaCO2-%increase. Patients with PaCO2-ValveDepl>60 mm Hg, pH≤7.2 and greater pH-%decrease were more likely to receive vasoactive medications, but perioperative PaCO2 and pH were not associated with adverse postoperative outcomes. CONCLUSIONS: Transient significant hypercapnia commonly occurs during transfemoral TAVR with deep sedation using propofol and dexmedetomidine. Although the incidence of postoperative outcomes does not appear to be affected by hypercapnia, the need for vasopressors and inotropes is increased. If deep sedation is required for TAVR, hypercapnia and the need for haemodynamic and ventilatory support should be anticipated.

Pulmonary Capillary Hemangiomatosis as a Rare Underlying Cause of Primary Pulmonary Hypertension: A Case Report in an Adolescent.

Despite its rarity, pulmonary capillary hemangiomatosis (PCH) presents a significant diagnostic challenge. Due to its similarity to other pulmonary vascular diseases, such as pulmonary veno-occlusive disease, it is characterized by abnormal pulmonary capillary proliferation, which is a rare cause of primary pulmonary hypertension. This case was the first reported instance of PCH in Shahid Rajaee Heart Hospital in Tehran, Iran, in 2023, which was confirmed by genetic testing. It highlighted the importance of considering PCH among the differential diagnoses for pulmonary hypertension, even in adolescent patients. The 13-year-old patient's main complaints were progressive exertional dyspnea and chest pain. He had no previous medical history and had not taken any pharmaceutical or herbal medications. Critical clinical findings included a heart murmur, an electrocardiogram revealing right ventricular hypertrophy, and echocardiogram evidence of pulmonary hypertension. The main diagnosis was PCH, as shown by CT findings of pulmonary artery dilatation and diffuse nodular ground glass opacities. Genetic tests indicated pathogenic EIF2AK4 mutations and suspicion of PCH. Therapeutic intervention included vasodilator therapy, which exacerbated the patient's condition. This case emphasized the importance of maintaining a high index of suspicion for rare causes of pulmonary hypertension, such as PCH. The outcome was to prepare the patient for lung transplantation. To differentiate PCH from other pulmonary vascular diseases, a combination of clinical presentation, radiologic studies, genetic analysis, and response to treatment is required to determine appropriate management, particularly lung transplantation.

Evaluating the Impact of Pulmonary Arterial Hypertension Therapies on Pericardial Effusion and Patient Survival.

Objectives: To evaluate the impact of Pulmonary Arterial Hypertension (PAH) therapies on the incidence of pericardial effusion and its prognostic implications for patient survival. Methods: This retrospective cohort study included 60 patients diagnosed with PAH at a high-volume tertiary care center, treated with intravenous or subcutaneous prostanoids. Data were collected from 2015 to 2019, including echocardiographic assessments, right heart catheterization, World Health Organization functional class evaluations, six-minute walk distance tests, and biomarkers such as brain natriuretic peptide and N-terminal prohormone of brain natriuretic peptide. Follow-up was conducted at least 90 days post-treatment initiation. Results: Pericardial effusion was observed in 31.7% of patients before therapy. Patients with moderate to large effusions had a significantly higher mortality risk (HR = 1.92; 95% CI 1.1-44.78; p =0.0044), while small effusions appeared protective (HR = 0.27; 95% CI 0.15-0.48; p =0.006). Survival rates declined from 89% at one year to 71% at three years post-therapy, with effusion presence correlating with more severe PAH manifestations. Conclusions: Initial pericardial effusion severity is a critical predictor of mortality in PAH patients. Early assessment and stratified management of pericardial effusion are essential for optimizing therapeutic outcomes in PAH management. Future research should explore targeted interventions for managing pericardial effusion to improve patient prognosis.

Smooth Muscle Ythdf2 Abrogation Ameliorates Pulmonary Vascular Remodeling by Regulating Myadm Transcript Stability.

BACKGROUND: The N6-methyladenosine (m6A) modification of RNA and its regulators have important roles in the pathogenesis of pulmonary hypertension (PH). Ythdf2 (YTH N6-methyladenosine RNA binding protein 2) is best known for its role in degrading m6A-modified mRNAs such as Hmox1 mRNA, which leads to alternative activation of macrophages in PH. Recent studies have also linked Ythdf2 to the proliferation of pulmonary artery smooth muscle cells (PASMCs). However, its specific roles in PASMCs and downstream targets during the development of PH remain unclear. METHODS: The expression and biological function of Ythdf2 in PASMCs were investigated in human and experimental models of PH. Smooth muscle cell-specific Ythdf2-deficient mice were used to assess the roles of Ythdf2 in PASMCs in vivo. Proteomic analysis, m6A sequencing, and RNA immunoprecipitation analysis were used to screen for potential downstream targets. RESULTS: Ythdf2 was significantly upregulated in human and rodent PH-PASMCs, and smooth muscle cell-specific Ythdf2 deficiency ameliorated PASMC proliferation, right ventricular hypertrophy, pulmonary vascular remodeling, and PH development. Higher expression of Ythdf2 promoted PASMC proliferation and PH by paradoxically stabilizing Myadm mRNA in an m6A-dependent manner. Loss of Ythdf2 decreased the expression of Myadm in PASMCs and pulmonary arteries, both in vitro and in vivo. Additionally, silencing Myadm inhibited the Ythdf2-dependent hyperproliferation of PASMCs by upregulating the cell cycle kinase inhibitor p21. CONCLUSIONS: We have identified a novel mechanism where the increased expression of Ythdf2 stimulates PH-PASMC proliferation through an m6A/Myadm/p21 pathway. Strategies targeting Ythdf2 in PASMCs might be useful additions to the therapeutic approach to PH.

Endothelial Heterogeneity in the Response to Autophagy Drives Small Vessel Muscularization in Pulmonary Hypertension.

BACKGROUND: Endothelial cell (EC) apoptosis and proliferation of apoptosis-resistant cells is a hallmark of pulmonary hypertension (PH). Yet, why some ECs die and others proliferate and how this contributes to vascular remodeling is unclear. We hypothesized that this differential response may: (1) relate to different EC subsets, namely pulmonary artery (PAECs) versus microvascular ECs (MVECs); (2) be attributable to autophagic activation in both EC subtypes; and (3) cause replacement of MVECs by PAECs with subsequent distal vessel muscularization. METHODS: EC subset responses to chronic hypoxia were assessed by single-cell RNA sequencing of murine lungs. Proliferative versus apoptotic responses, activation, and role of autophagy were assessed in human and rat PAECs and MVECs, and in precision-cut lung slices of wild-type mice or mice with endothelial deficiency in the autophagy-related gene 7 (Atg7EN-KO). Abundance of PAECs versus MVECs in precapillary microvessels was assessed in lung tissue from patients with PH and animal models on the basis of structural or surface markers. RESULTS: In vitro and in vivo, PAECs proliferated in response to hypoxia, whereas MVECs underwent apoptosis. Single-cell RNA sequencing analyses support these findings in that hypoxia induced an antiapoptotic, proliferative phenotype in arterial ECs, whereas capillary ECs showed a propensity for cell death. These distinct responses were prevented in hypoxic Atg7EN-KO mice or after ATG7 silencing, yet replicated by autophagy stimulation. In lung tissue from mice, rats, or patients with PH, the abundance of PAECs in precapillary arterioles was increased, and that of MVECs reduced relative to controls, indicating replacement of microvascular by macrovascular ECs. EC replacement was prevented by genetic or pharmacological inhibition of autophagy in vivo. Conditioned medium from hypoxic PAECs yet not MVECs promoted pulmonary artery smooth muscle cell proliferation and migration in a platelet-derived growth factor-dependent manner. Autophagy inhibition attenuated PH development and distal vessel muscularization in preclinical models. CONCLUSIONS: Autophagic activation by hypoxia induces in parallel PAEC proliferation and MVEC apoptosis. These differential responses cause a progressive replacement of MVECs by PAECs in precapillary pulmonary arterioles, thus providing a macrovascular context that in turn promotes pulmonary artery smooth muscle cell proliferation and migration, ultimately driving distal vessel muscularization and the development of PH.

Tadalafil for Treatment of Combined Postcapillary and Precapillary Pulmonary Hypertension in Patients With Heart Failure and Preserved Ejection Fraction: A Randomized Controlled Phase 3 Study.

BACKGROUND: We assessed the efficacy and safety of tadalafil, a phosphodiesterase type 5 inhibitor, in patients with heart failure with preserved ejection fraction and combined postcapillary and precapillary pulmonary hypertension. METHODS: In the double-blind PASSION study (Phosphodiesterase-5 Inhibition in Patients With Heart Failure With Preserved Ejection Fraction and Combined Post- and Pre-Capillary Pulmonary Hypertension), patients with heart failure with preserved ejection fraction and combined postcapillary and precapillary pulmonary hypertension were randomized 1:1 to receive tadalafil at a target dose of 40 mg or placebo. The primary end point was the time to the first composite event of adjudicated heart failure hospitalization or all-cause death. Secondary end points included all-cause mortality and improvements in New York Heart Association functional class or ≥10% improvement in 6-minute walking distance from baseline. RESULTS: Initially targeting 372 patients, the study was terminated early because of disruption in study medication supply. At that point, 125 patients had been randomized (placebo: 63; tadalafil: 62,). Combined primary end-point events occurred in 20 patients (32%) assigned to placebo and 17 patients (27%) assigned to tadalafil (hazard ratio, 1.02 [95% CI, 0.52-2.01]; P=0.95). There was a possible signal of higher all-cause mortality in the tadalafil group (hazard ratio, 5.10 [95% CI, 1.10-23.69]; P=0.04). No significant between-group differences were observed in other secondary end points. Serious adverse events occurred in 29 participants (48%) in the tadalafil group and 35 (56%) in the placebo group. CONCLUSIONS: The PASSION trial, terminated prematurely due to study medication supply disruption, does not support tadalafil use in patients with heart failure with preserved ejection fraction and combined postcapillary and precapillary pulmonary hypertension, with potential safety concerns and no observed benefits in primary and secondary end points. REGISTRATION: URL: https://www.clinicaltrialsregister.eu/; Unique identifier: 2017-003688-37. URL: https://drks.de; Unique identifier: DRKS -DRKS00014595.

Plasma Proteomics Identifies B2M as a Regulator of Pulmonary Hypertension in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Pulmonary hypertension (PH) represents an important phenotype in heart failure with preserved ejection fraction (HFpEF). However, management of PH-HFpEF is challenging because mechanisms involved in the regulation of PH-HFpEF remain unclear. METHODS: We used a mass spectrometry-based comparative plasma proteomics approach as a sensitive and comprehensive hypothesis-generating discovery technique to profile proteins in patients with PH-HFpEF and control subjects. We then validated and investigated the role of one of the identified proteins using in vitro cell cultures, in vivo animal models, and independent cohort of human samples. RESULTS: Plasma proteomics identified high protein abundance levels of B2M (ß2-microglobulin) in patients with PH-HFpEF. Interestingly, both circulating and skeletal muscle levels of B2M were increased in mice with skeletal muscle SIRT3 (sirtuin-3) deficiency or high-fat diet-induced PH-HFpEF. Plasma and muscle biopsies from a validation cohort of PH-HFpEF patients were found to have increased B2M levels, which positively correlated with disease severity, especially pulmonary capillary wedge pressure and right atrial pressure at rest. Not only did the administration of exogenous B2M promote migration/proliferation in pulmonary arterial vascular endothelial cells but it also increased PCNA (proliferating cell nuclear antigen) expression and cell proliferation in pulmonary arterial vascular smooth muscle cells. Finally, B2m deletion improved glucose intolerance, reduced pulmonary vascular remodeling, lowered PH, and attenuated RV hypertrophy in mice with high-fat diet-induced PH-HFpEF. CONCLUSIONS: Patients with PH-HFpEF display higher circulating and skeletal muscle expression levels of B2M, the magnitude of which correlates with disease severity. Our findings also reveal a previously unknown pathogenic role of B2M in the regulation of pulmonary vascular proliferative remodeling and PH-HFpEF. These data suggest that circulating and skeletal muscle B2M can be promising targets for the management of PH-HFpEF.

Cardiovascular Complications With Delivery Hospitalizations in Patients With Pulmonary Hypertension: A Nationwide Study From 2011 to 2020.

BACKGROUND: Pregnancy in patients with pulmonary hypertension (PH) is associated with a heightened risk of medical complications including right heart failure, pulmonary edema, and arrhythmias. Our study investigated the association between PH and these complications during delivery. METHODS AND RESULTS: The National Inpatient Sample was used to identify delivery hospitalizations from 2011 to 2020. Multivariable logistic regression was performed to study the association of PH with the primary outcomes of in-hospital medical and obstetric complications. A total of 37 482 207 delivery hospitalizations in women ≥18 years of age were identified, of which 9593 patients had PH. Pregnant patients with PH had higher incidence of complications during delivery including preeclampsia/eclampsia, arrhythmias, and pulmonary edema among others, compared with those without PH. Pregnant patients with PH also had a higher incidence of in-hospital mortality compared with those without PH (0.51% versus 0.007%). In propensity-matched analyses, PH was still significantly associated with a higher risk of in-hospital mortality (odds ratio [OR], 5.02 [95% CI, 1.82-13.90]; P=0.001), pulmonary edema (OR, 9.11 [95% CI, 6.34-13.10]; P<0.001), peripartum cardiomyopathy (OR, 1.85 [95% CI, 1.37-2.50]; P<0.001), venous thromboembolism (OR, 12.60 [95% CI, 6.04-26.10]; P<0.001), cardiac arrhythmias (OR, 6.11 [95% CI, 4.97-7.53]; P<0.001), acute kidney injury (OR, 3.72 [95% CI, 2.86-4.84]; P<0.001), preeclampsia/eclampsia (OR, 2.24 [95% CI, 1.95-2.58]; P<0.001), and acute coronary syndrome (OR, 2.01 [95% CI, 1.06-3.80]; P=0.03), compared with pregnant patients without PH. CONCLUSIONS: Delivery hospitalizations in patients with PH are associated with a high risk of mortality, pulmonary edema, peripartum cardiomyopathy, venous thromboembolism, arrhythmias, acute kidney injury, preeclampsia/eclampsia, and acute coronary syndrome.

Ultrasound Neuromodulation of an Anti-Inflammatory Pathway at the Spleen Improves Experimental Pulmonary Hypertension.

BACKGROUND: Inflammation is pathogenically implicated in pulmonary arterial hypertension; however, it has not been adequately targeted therapeutically. We investigated whether neuromodulation of an anti-inflammatory neuroimmune pathway involving the splenic nerve using noninvasive, focused ultrasound stimulation of the spleen (sFUS) can improve experimental pulmonary hypertension. METHODS: Pulmonary hypertension was induced in rats either by Sugen 5416 (20 mg/kg SQ) injection, followed by 21 (or 35) days of hypoxia (sugen/hypoxia model), or by monocrotaline (60 mg/kg IP) injection (monocrotaline model). Animals were randomized to receive either 12-minute-long sessions of sFUS daily or sham stimulation for 14 days. Catheterizations, echocardiography, indices of autonomic function, lung and heart histology and immunohistochemistry, spleen flow cytometry, and lung single-cell RNA sequencing were performed after treatment to assess the effects of sFUS. RESULTS: Splenic denervation right before induction of pulmonary hypertension results in a more severe disease phenotype. In both sugen/hypoxia and monocrotaline models, sFUS treatment reduces right ventricular systolic pressure by 25% to 30% compared with sham treatment, without affecting systemic pressure, and improves right ventricular function and autonomic indices. sFUS reduces wall thickness, apoptosis, and proliferation in small pulmonary arterioles, suppresses CD3+ and CD68+ cell infiltration in lungs and right ventricular fibrosis and hypertrophy and lowers BNP (brain natriuretic peptide). Beneficial effects persist for weeks after sFUS discontinuation and are more robust with early and longer treatment. Splenic denervation abolishes sFUS therapeutic benefits. sFUS partially normalizes CD68+ and CD8+ T-cell counts in the spleen and downregulates several inflammatory genes and pathways in nonclassical and classical monocytes and macrophages in the lung. Differentially expressed genes in those cell types are significantly enriched for human pulmonary arterial hypertension-associated genes. CONCLUSIONS: sFUS causes dose-dependent, sustained improvement of hemodynamic, autonomic, laboratory, and pathological manifestations in 2 models of experimental pulmonary hypertension. Mechanistically, sFUS normalizes immune cell populations in the spleen and downregulates inflammatory genes and pathways in the lung, many of which are relevant in human disease.

Laterality of CT-measured hepatic extracellular volume fraction in patients with chronic thromboembolic pulmonary hypertension.

PURPOSE: This study examines the hepatic extracellular volume fraction (ECV) disparity between the left and right lobes (ECV_left and ECV_right) in patients with chronic thromboembolic pulmonary hypertension (CTEPH), its association with right heart catheterization (RHC) metrics, and with intolerance to increased pulmonary hypertension (PH)-targeted medication dosages. METHODS: We retrospectively analyzed 72 CTEPH-diagnosed patients who underwent equilibrium-phase abdominal dual-energy CT (DECT) and RHC. Hepatic ECVs, derived from DECT's iodine maps using circular regions of interest in the liver and aorta, were correlated with RHC parameters via Spearman's rank correlation and lobe differences through the Wilcoxon signed-rank test. Logistic regression assessed cases with ECV_left exceeding ECV_right by > 0.05, while receiver operating characteristic curve analysis gauged ECVs' predictive power for medication intolerance. RESULTS: Of the 72 patients (57 females; median age 69), ECV_total (0.24, IQR 0.20-0.27) moderately correlated with RHC parameters (rs = 0.28, -0.24, 0.3 for mean pulmonary arterial pressure, cardiac index [CI], and pulmonary vascular resistance index, respectively). ECV_left significantly surpassed ECV_right (0.25 vs. 0.22, p < 0.001), with a greater ECV_left by > 0.05 indicating notably lower CI (p < 0.001). In 27 patients on PH medication, ECV_left effectively predicted medication intolerance (AUC = 0.84). CONCLUSION: In CTEPH patients, hepatic ECV correlated with RHC metrics, where elevated left lobe ECV suggested reduced CI and potential medication intolerance.

Continuous heart monitoring to evaluate treatment effects in pulmonary hypertension.

BACKGROUND: The treatment of pulmonary hypertension (PH) has improved rapidly in recent decades. There is increasing evidence to support the role of early intervention and treatment in affecting clinical outcomes in PH. OBJECTIVES: To assess treatment effects before and after the escalation of specific PH treatments using continuous heart monitoring with a Reveal LINQ loop recorder. METHODS: Patients were compared before and after treatment escalation. Treatment escalation was defined as an additional pulmonary arterial hypertension (PAH) drug, pulmonary endarterectomy, percutaneous balloon angioplasty or bilateral lung transplantation. Specifically, changes in heart rate variability (HRV), heart rate (HR) and physical activity were assessed. RESULTS: In this prospective study, 41 patients (27 with PAH and 14 with chronic thromboembolic pulmonary hypertension (CTEPH)) were enrolled. Among them, 15 (36.6%) patients underwent PH treatment escalation. Prior to escalation, patients were monitored for a median of 100 (range: 68-100) days and after therapy escalation for a median duration of 165 (range: 89-308) days. In the escalation group, there was a significant increase in HRV, physical activity indexed by daytime HR and a significant decrease in nighttime HR assessed at baseline and after treatment escalation in both the PAH and CTEPH groups. This was paralleled by significant improvements in WHO functional class, 6-min walking distance and N-terminal pro-b-type natriuretic peptide. CONCLUSIONS: This is the first study to demonstrate an association between specific PH therapies and changes in HRV, HR nighttime and physical activity. This indicates the potential of continuous monitoring in the evaluation of treatment effects in PH.