Human induced pluripotent stem cell-derived cardiomyocyte patches ameliorate right ventricular function in a rat pressure-overloaded right ventricle model

Right ventricular (RV) failure following surgical repair of congenital heart disease affects survival. Human induced pluripotent stem cell-derived cardiomyocyte (hiPS-CM) sheet transplantation ameliorated left ventricular dysfunction in preclinical studies, indicating its efficacy in RV failure in congenital heart disease. This study aimed to evaluate whether hiPS-CMs could improve RV function in rats with pressure-overloaded RV failure. F344/NJcl-rnu/rnu rats underwent pulmonary artery banding (PAB) via left thoracotomy. Four weeks after PAB, hiPS-CM patch transplantation to the RV was performed in the hiPS-CM group (n = 33), and a sham operation was performed in the sham group (n = 18). We evaluated cardiac catheterization, positron emission tomography data, and pathological results 8 weeks following PAB. RV end-diastolic pressure, the time constant of isovolumic relaxation, and end-diastolic pressure-volume relation were significantly ameliorated in the hiPS-CM group compared with in the sham group. Picrosirius red staining revealed that anti-fibrotic effects were significantly higher in the hiPS-CM group than in the sham group. Von Willebrand factor staining revealed significantly higher myocardial capillary vascular density in the hiPS-CM group than in the sham group. hiPS-CMs were detected in the epicardium 4 weeks after hiPS-CM sheet transplantation. The angiogenic gene expression in the myocardium was significantly higher in the hiPS-CM group than in the sham group. Overall, in rats with pressure-overloaded RV failure, hiPS-CM patch transplantation could improve diastolic function, suppress ventricular fibrosis, and increase capillary density, suggesting that it is a promising treatment for RV failure.

Impact of cardiosphere-derived cells on the maladapted right ventricular muscle in a rat sugen/hypoxia model of pulmonary hypertension with right ventricular dysfunction

BACKGROUND AND AIMS

With pulmonary arterial hypertension (PAH), right ventricular (RV) function is a major determinant of survival. Despite current therapies, maladaptive changes ensue in the RV muscle of PAH patients, culminating in RV dysfunction and failure. The aims of the study were to evaluate the impact of intra-coronary (IC) cardiosphere-derived cells (CDCs) in attenuating the maladaptive pathobiology in the RV muscle and evaluating mechanisms underlying improvements in RV function.

METHODS

Two groups of the Sugen/Hypoxia rat model of PAH, exhibiting significantly reduced RV function, via TAPSE measurements, received either intracoronary infusion of CDCs or PBS placebo. Immunohistochemistry methods were used to assess RV pathobiological changes. Additionally, advanced proteomics were employed to examine protein signaling pathways and upstream regulators.

RESULTS

RV muscle capillarity was significantly reduced in the PAH rats while RV muscle fibrosis was increased. IC CDCs significantly increased RV muscle capillarity back to levels noted in healthy rats and reduced RV free wall fibrosis. Further, a significant reduction in iNOS+ (M1) macrophages was also observed within the RV free wall in CDC-treated animals. Proteomic analysis of RV muscle in CDC- or PBS-treated PAH rats showed alterations in protein pathways related to inflammation, fibrosis, autophagy, cell vitality, and angiogenesis. These changes were consistent with putative coordination by a small number of key upstream regulators (MYC, TP53, HNF4A, TGFB1, and KRAS). TAPSE was significantly reduced in PBS-treated animals but was maintained at or above baseline levels in CDC-treated animals.

CONCLUSIONS

CDC therapy can significantly impact the maladaptive milieu of the RV myocardium in advanced PAH, by altering several pathobiological pathways. Such adjunctive therapy, in addition to those employed to reduce pulmonary vascular resistance, would be a great advance in managing RV failure, for which no effective current approved therapies exist.

Identification of serum C4BPA as a potential diagnostic marker of right ventricular remodelling via proteomic analysis

AIMS

Right ventricular (RV) remodelling, a progressive condition characterized by maladaptive cardiac structural and functional changes, primarily results from prolonged pressure overload in patients with pulmonary hypertension (PH). Accurate, universal and easy-to-use biomarkers for assessing the severity of RV remodelling are lacking. This study aimed to identify serum proteins as potential biomarkers of RV remodelling using high-throughput proteomic analysis-based screening.

METHODS

Sprague-Dawley rats were subjected to sham surgery (control group) or pulmonary artery banding for 4 weeks with 2.3-mm diameter and 1.8-mm diameter rubber rings to induce mild and severe RV modelling, respectively. Serum proteomic profiling revealed 170 differentially expressed serum proteins (DEPs) among the three groups, and three DEPs gradually increased with worsening RV remodelling. Among the three DEPs, C4b-binding protein alpha chain (C4BPA) exhibited the highest upregulation in the severe group (6.93 vs. 16.5 ng/mL, P < 0.001), and linear regression analysis revealed a negative correlation between serum C4BPA levels and tricuspid annular plane systolic excursion (TAPSE) in rats [beta = -0.78, 95% confidence interval (CI) -14.5 to -7.11, P < 0.001]. The diagnostic power of C4BPA was further validated in 127 patients (34 with adaptive RV pressure overload, 36 with maladaptive RV pressure overload, 32 with left ventricular hypertrophy and 25 controls). Control and left ventricular hypertrophy patients exhibited lower serum C4BPA levels than the two RV groups, and serum C4BPA levels were higher in patients with maladaptive RV than in those with adaptive RV (754 vs. 524 pg/mL, P < 0.001). Linear regression analysis revealed a negative correlation between serum C4BPA levels and TAPSE in PH patients. The predictive power of C4BPA for maladaptive RV function in PH patients, indicated by receiver operating characteristic analysis (cut-off value 573 pg/mL, area under the curve 0.792), was as good as that of B-type natriuretic peptide (BNP). High serum C4BPA levels (≥573 pg/mL) were associated with lower TAPSE/pulmonary arterial systolic pressure ratios (P < 0.001) and higher BNP levels (P < 0.001).

CONCLUSIONS

Serum C4BPA may represent a novel diagnostic biomarker for RV pathological remodelling associated with RV maladaptation in PH patients.

Sexual dimorphism in right ventricular adaptation to pressure overload involves differential angiogenic response

This study investigated the sexual dimorphism in right ventricle (RV) remodeling in right heart failure susceptible Fischer CDF rats using the pulmonary artery banding (PAB) model. Echocardiography and hemodynamic measurements were performed in adult male and female Fischer CDF rats at 1- or 2-wk post-PAB. RV systolic pressure and RV hypertrophy were significantly elevated in PAB rats compared with sham control at 1- and 2-wk post-PAB; however, no differences were observed between male and female rats. Increase in cardiomyocyte cross-sectional area and RV end-diastolic diameter was observed in male rats compared with female rats at 2-wk post-PAB. Conversely, higher fractional area change and cardiac index were observed in female rats compared with male rats at 2-wk post-PAB. To explore the mechanisms, a focused PCR array was performed and higher expression of angiogenic genes, including sphingosine kinase-1 (Sphk1), was observed in the RV of female rats compared with male rats. Consistent with the higher angiogenic gene expression, female rats had a higher RV vascular density at 2-wk post-PAB compared with male rats. Female RV endothelial cells (RVECs) had better angiogenic ability compared with male cells that was potentiated by estradiol. Furthermore, effect of estradiol on RVECs was inhibited by Sphk1 inhibitor (PF-543). Together, female Fischer CDF rats develop adaptive RV remodeling post-PAB compared with maladaptive remodeling in male rats. Moreover, the adaptive remodeling in female rats is associated with better RV angiogenic response that may result from better angiogenic ability of female RVECs and proangiogenic effects of estradiol through Sphk1.NEW & NOTEWORTHY Female patients with pulmonary hypertension have better right ventricular adaptation compared with male. These sex differences were modeled in right heart failure susceptible Fischer CDF rat using pulmonary artery banding model. Preservation of right ventricular function in female rats is linked to better right ventricular angiogenic response that involves higher intrinsic angiogenic ability of female right ventricular endothelial cells together with the proangiogenic effects of female sex hormone estradiol through sphingosine kinase-1.

Homeostatic Role of Decorin in Right Ventricular Pressure Overload and Pulmonary Hypertension Induced Remodeling

Right ventricular (RV) pressure loading induces RV profibrotic signaling and fibrosis associated with RV dysfunction. RV decorin protein levels are decreased in patients with chronic RV pressure loading. RV decorin protein levels are also decreased in 4 animal models of mechanical RV pressure loading and pulmonary arterial hypertension. Human cardiac fibroblasts overexpressing decorin show diminished collagen-1 secretion in response to mechanical or chemical profibrotic stress while decorin knockout human cardiac fibroblasts show increased collagen-1 secretion in response to stress. Downregulation of decorin may play a key role in upregulating transforming growth factor-β1 profibrotic signaling and fibrosis that contribute to RV dysfunction in RV pressure loading.

Emerging Mechanistic Insights and Therapeutic Strategies for Pulmonary Arterial Hypertension: A Focus on Right Ventricular Dysfunction and Novel Treatment Pathways

Background/Objectives: Pulmonary arterial hypertension (PAH) is a progressive vascular disorder characterized by increased pulmonary vascular resistance, right ventricular dysfunction, and high mortality rates. Despite advancements in vasodilatory therapies, PAH remains a life-threatening condition with limited curative options. This review aimed to explore emerging molecular mechanisms, novel therapeutic targets, and future research directions in PAH treatment, focusing on strategies to improve long-term patient outcomes. Methods: This review synthesized recent advancements in PAH pathophysiology and therapeutic development. A structured literature search was conducted on PubMed and ClinicalTrials.gov using keywords such as "Pulmonary Arterial Hypertension", "vascular remodeling", "metabolic dysfunction", and "emerging therapies". Studies published between 2015 and 2025 were included, with a focus on preclinical models, clinical trials, and translational research. Key areas of investigation include vascular remodeling, metabolic dysregulation, inflammation, and right ventricular dysfunction. The review also evaluated the potential of novel pharmacological agents, gene-based therapies, and AI-driven diagnostics for PAH management. Results: Recent studies highlight dysregulated BMPR2 signaling, epigenetic modifications, and inflammatory cytokine pathways as critical contributors to PAH progression. Emerging therapies such as JAK-STAT inhibitors, metabolic reprogramming agents, and mesenchymal stromal cell-derived extracellular vesicles (EVs) show promise in preclinical and early clinical trials. Additionally, AI-enhanced imaging and non-invasive biomarkers are improving PAH diagnostics. Future research directions emphasize precision medicine approaches and the development of RV-targeted therapies. Conclusions: PAH remains a complex and fatal disease requiring multifaceted therapeutic strategies beyond traditional vasodilation. Advances in molecular-targeted treatments, AI-driven diagnostics, and personalized medicine offer new hope for disease-modifying interventions. Future research must bridge translational gaps to bring novel therapies from bench to bedside, improving survival and quality of life in PAH patients.

Suppressing the expression of steroidogenic acute regulatory protein (StAR) in the myocardium by spironolactone contributes to the improvement of right ventricular remodeling in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a progressive condition that frequently leads to right ventricular (RV) remodeling. Aldosterone promotes vascular and RV remodeling. The upregulation of steroidogenic acute regulatory protein (StAR) stimulates aldosterone synthesis. However, the expression of StAR in the myocardium under PAH conditions remains unknown. To investigate the expression of StAR in the myocardium and its association with RV remodeling in PAH, utilizing spironolactone as a treatment. A PAH model was created using male Sprague-Dawley rats, which received a subcutaneous injection of Sugen5416 (20 mg/kg) and were exposed to hypoxia (10% O2) for 2 weeks, followed by 2 weeks of normoxia. The animals were then divided into two groups, with one group receiving spironolactone (25 mg/kg/day) for an additional 4 weeks, while the other group did not. H9c2 cells were cultured under hypoxic conditions (37 °C, 1% O2, 5% CO2) with or without spironolactone treatment. In the model rats, RV systolic pressure and the Fulton index, both of which increased upon exposure to Sugen5416 and hypoxia, significantly decreased with spironolactone treatment. In H9c2 cells, hypoxic exposure elevated aldosterone levels, while spironolactone treatment significantly suppressed aldosterone production. Suppression of StAR expression in the myocardium via spironolactone contributes to the improvement of RV remodeling in PAH. Spironolactone may offer a valuable therapeutic strategy for RV remodeling in patients with PAH.

LOXL2 inhibition ameliorates pulmonary artery remodeling in pulmonary hypertension

Conduit pulmonary arterial stiffening and the resultant increase in pulmonary vascular impedance have emerged as an important underlying driver of pulmonary arterial hypertension (PAH). Given that matrix deposition is central to vascular remodeling, we evaluated the role of the collagen cross-linking enzyme lysyl oxidase like 2 (LOXL2) in this study. Human pulmonary artery smooth muscle cells (PASMCs) subjected to hypoxia showed increased LOXL2 secretion. LOXL2 activity and expression were markedly higher in primary PASMCs isolated from the pulmonary arteries of the rat Sugen 5416 + hypoxia (SuHx) model of severe pulmonary hypertension (PH). Similarly, LOXL2 protein and mRNA levels were increased in the pulmonary arteries (PA) and lungs of rats with PH (SuHx and monocrotaline (MCT) models). Pulmonary arteries (PAs) isolated from the rats with PH exhibited hypercontractility to phenylephrine and attenuated vasorelaxation elicited by acetylcholine, indicating severe endothelial dysfunction. Tensile testing revealed a significant increase in PA stiffness in PH. Treatment with PAT-1251, a novel small-molecule LOXL2 inhibitor, improved active and passive properties of the PA ex vivo. There was an improvement in right heart function as measured by right ventricular pressure volume loops in vivo with PAT-1251. Importantly, PAT-1251 treatment ameliorated PH, resulting in improved pulmonary artery pressures, right ventricular remodeling, and survival. Hypoxia-induced LOXL2 activation is a causal mechanism in pulmonary artery stiffening in PH and pulmonary artery mechanical and functional decline. LOXL2 inhibition with PAT-1251 could be a promising approach to improve pulmonary artery pressures, right ventricular elastance, cardiac relaxation, and survival in PAH.NEW & NOTEWORTHY Pulmonary arterial stiffening contributes to the progression of PAH and the deterioration of right heart function. This study shows that LOXL2 is upregulated in rat models of PH. LOXL2 inhibition halts pulmonary vascular remodeling and improves PA contractility, endothelial function, and PA pressure, resulting in prolonged survival. Thus, LOXL2 is an important mediator of PA remodeling and stiffening in PH and a promising target to improve PA pressures and survival in PH.

Research progress on the role of p53 in pulmonary arterial hypertension

PURPOSE OF REVIEW

Pulmonary arterial hypertension (PAH) is a devastating disease characterized by increased pulmonary vascular resistance and pulmonary arterial pressure. At present, the definitive pathology of PAH has not been elucidated and its effective treatment remains lacking. Despite PAHs having multiple pathogeneses, the cancer-like characteristics of cells have been considered the main reason for PAH progression.

RECENT FINDINGS

p53 protein, an important tumor suppressor, regulates a multitude of gene expressions to maintain normal cellular functions and suppress the progression of malignant tumors. Recently, p53 has been found to exert multiple biological effects on cardiovascular diseases. Since PAH shares similar metabolic features with cancer cells, the regulatory roles of p53 in PAH are mainly the induction of cell cycle, inhibition of cell proliferation, and promotion of apoptosis.

SUMMARY

This paper summarized the advanced findings on the molecular mechanisms and regulatory functions of p53 in PAH, aiming to reveal the potential therapeutic targets for PAH.

Therapeutic Potential of Treprostinil Inhalation Powder for Patients with Pulmonary Arterial Hypertension: Evidence to Date

Pulmonary arterial hypertension (PAH) is a complex and incurable disease for which pulmonary vasodilators remain the core therapy. Of the three primary pathways that vasodilators target, the prostacyclin pathway was the earliest to be used and currently has the largest number of modalities for drug delivery. Inhaled treprostinil has been introduced as a treatment option in PAH and, more recently, pulmonary hypertension (PH) due to interstitial lung disease (PH-ILD), and the earlier nebulized form has been joined by a dry powder form allowing for more convenient use. In this review, we discuss inhaled treprostinil, focusing on the dry powder inhalation (DPI) formulation, and explore its dosing, applications, and evidence to support patient tolerance and acceptance. Recent trials underpinning the evidence for use of inhaled treprostinil and the most recent developments concerning the drug are discussed. Finally, the review looks briefly into premarket formulations of inhaled treprostinil and relevant early studies suggesting efficacy in PAH treatment.

Evolving Applications of Echocardiography in the Evaluation of Left Atrial and Right Ventricular Strain

PURPOSE OF REVIEW

Speckle-tracking echocardiography (STE) can assess myocardial motion in non-LV chambers-including assessment of left atrial (LA) and right ventricular (RV) strain. This review seeks to highlight the diagnostic, prognostic, and clinical significance of these parameters in heart failure, atrial fibrillation (AF), diastolic dysfunction, pulmonary hypertension (PH), tricuspid regurgitation, and heart transplant recipients.

RECENT FINDINGS

Impaired LA strain reflects worse LV diastolic function in individuals with and without HF, and this is associated with decreased exercise capacity. Initiating treatments targeting these functional aspects may enhance exercise capacity and potentially prevent heart failure (HF). Impaired LA strain also identifies patients with a high risk of AF, and this recognition may lead to preventive strategies. Impaired RV strain has significant clinical and prognostic implications across various clinical scenarios, including HF, PH, tricuspid regurgitation, or in heart transplant recipients. STE should not be limited to the assessment of deformation of the LV myocardium. The use of LA and RV strain is supported by a substantial evidence base, and these parameters should be used more widely.

Proteasome inhibitor bortezomib prevents proliferation and migration of pulmonary arterial smooth muscle cells

Pulmonary vascular remodeling is a key pathological process of pulmonary arterial hypertension (PAH), characterized by uncontrolled proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs). Bortezomib (BTZ) is the first Food and Drug Administration (FDA)-approved proteasome inhibitor for multiple myeloma treatment. Recently, there is emerging evidence showing its effect on reversing PAH, although its mechanisms are not well understood. In this study, anti-proliferative and anti-migratory effects of BTZ on PASMCs were first examined by different inducers such as fetal bovine serum (FBS), angiotensin II (Ang II) and platelet-derived growth factor (PDGF)-BB, while potential mechanisms including cellular reactive oxygen species (ROS) and mitochondrial ROS were then investigated; finally, signal transduction of ERK and Akt was examined. Our results showed that BTZ attenuated FBS-, Ang II- and PDGF-BB-induced proliferation and migration, with associated decreased cellular ROS production and mitochondrial ROS production. In addition, the phosphorylation of ERK and Akt induced by Ang II and PDGF-BB was also inhibited by BTZ treatment. This study indicates that BTZ can prevent proliferation and migration of PASMCs, which are possibly mediated by decreased ROS production and down-regulation of ERK and Akt. Thus, proteasome inhibition can be a novel pharmacological target in the management of PAH.

Insights Into Differences in Pulmonary Hemodynamics in Hispanic Patients With Pulmonary Arterial Hypertension

Background

Emerging data suggest that Hispanic patients with pulmonary arterial hypertension (PAH) exhibit improved survival rates compared to individuals of other ethnicities with similar baseline hemodynamics. However, the underlying reasons for this survival advantage remain unclear. This study focused on comparing pulmonary hemodynamics in Hispanic and non-Hispanic PAH patients and how these differences may contribute to varied clinical outcomes.

Methods

A retrospective analysis of right heart catheterization data was conducted on a treatment-naive PAH patient cohort from a single center.

Results

Over a 10-year period, a total of 226 PAH patients were identified, of which 138 (61%) were Hispanic and 88 (39%) were non-Hispanic. Hispanic patients presented with lower pulmonary artery pressures, lower pulmonary vascular resistance, and exhibited significantly higher pulmonary arterial compliance (PAc). Hispanic patients had better 5-year survival rates.

Conclusions

This study highlights the importance of exploring phenotypic differences in ethnically diverse PAH cohorts.

Association between P-pulmonale and respiratory morbidity in COPD: a secondary analysis of the BLOCK-COPD trial

RATIONALE

Pulmonary hypertension (PH) in COPD confers increased risk of exacerbations (ECOPD). Electrocardiogram (ECG) indicators of PH are prognostic both in PH and COPD. In the Beta-Blockers for the Prevention of Acute Exacerbations of COPD (BLOCK-COPD) trial, metoprolol increased risk of severe ECOPD through unclear mechanisms.

OBJECTIVE

We evaluated whether an ECG indicator of PH, P-pulmonale, would be associated with ECOPD and whether participants with P-pulmonale randomized to metoprolol were at higher risk of ECOPD and worsened respiratory symptoms given the potential detrimental effects of beta-blockers in PH.

METHODS

ECGs of 501 participants were analyzed for P-pulmonale (P wave enlargement in lead II). Cox proportional hazards models evaluated for associations between P-pulmonale and time to ECOPD (all and severe) for all participants and by treatment assignment (metoprolol vs. placebo). Linear mixed-effects models evaluated the association between treatment assignment and P-pulmonale on change in symptom scores (measured by CAT and SOBQ).

RESULTS

We identified no association between P-pulmonale and risk of any ECOPD or severe ECOPD. However, in individuals with P-pulmonale, metoprolol was associated with increased risk for ECOPD (aHR 2.92, 95% CI: 1.45-5.85). There was no association between metoprolol and ECOPD in individuals without P-pulmonale (aHR 1.01, 95% CI: 0.77-1.31). Individuals with P-pulmonale assigned to metoprolol experienced worsening symptoms (mean increase of 3.95, 95% CI: 1.32-6.58) whereas those assigned to placebo experienced a mean improvement in CAT score of -2.45 (95% CI: -0.30- -4.61).

CONCLUSIONS

In individuals with P-pulmonale, metoprolol was associated with increased exacerbation risk and worsened symptoms. These findings may explain the findings observed in BLOCK-COPD.

Transcriptional profiling unveils molecular subgroups of adaptive and maladaptive right ventricular remodeling in pulmonary hypertension

Right ventricular (RV) function is critical to prognosis in all forms of pulmonary hypertension. Here we perform molecular phenotyping of RV remodeling by transcriptome analysis of RV tissue obtained from 40 individuals, and two animal models of RV dysfunction of both sexes. Our unsupervised clustering analysis identified 'early' and 'late' subgroups within compensated and decompensated states, characterized by the expression of distinct signaling pathways, while fatty acid metabolism and estrogen response appeared to underlie sex-specific differences in RV adaptation. The circulating levels of several extracellular matrix proteins deregulated in decompensated RV subgroups were assessed in two independent cohorts of individuals with pulmonary arterial hypertension, revealing that NID1, C1QTNF1 and CRTAC1 predicted the development of a maladaptive RV state, as defined by magnetic resonance imaging parameters, and were associated with worse clinical outcomes. Our study provides a resource for subphenotyping RV states, identifying state-specific biomarkers, and potential therapeutic targets for RV dysfunction.

Fibroblast growth factor 23 as a biomarker of right ventricular dysfunction in pulmonary hypertension

BACKGROUND

Fibroblast growth factor 23 (FGF-23) has been associated with left ventricular hypertrophy (LVH) and heart failure. However, its role in right ventricular (RV) remodeling and RV failure is unknown. This study analyzed the utility of FGF-23 as a biomarker of RV function in patients with pulmonary hypertension (PH).

METHODS

In this observational study, FGF-23 was measured in the plasma of patients with PH (n = 627), dilated cardiomyopathy (DCM, n = 59), or LVH with severe aortic stenosis (n = 35). Participants without LV or RV abnormalities served as controls (n = 36).

RESULTS

Median FGF-23 plasma levels were higher in PH patients than in healthy controls (p < 0.001). There were no significant differences between PH, DCM, and LVH patients. Analysis across tertiles of FGF-23 levels in PH patients revealed an association between higher FGF-23 levels and higher levels of NT-proBNP and worse renal function. Furthermore, patients in the high-FGF-23 tertile had a higher pulmonary vascular resistance (PVR), mean pulmonary artery pressure, and right atrial pressure and a lower cardiac index (CI) than patients in the low tertile (p < 0.001 for all comparisons). Higher FGF-23 levels were associated with higher RV end-diastolic diameter and lower tricuspid annular plane systolic excursions (TAPSE) and TAPSE/PASP. Receiver operating characteristic analysis revealed FGF-23 as a good predictor of RV maladaptation, defined as TAPSE < 17 mm and CI < 2.5 L/min/m2. Association of FGF-23 with parameters of RV function was independent of the glomerular filtration rate in regression analysis.

CONCLUSION

FGF-23 may serve as a biomarker for maladaptive RV remodeling in patients with PH.

Medical Management of Right Ventricular Dysfunction in Pulmonary Arterial Hypertension

PURPOSE OF REVIEW

The purpose of this review is to overview the most relevant and recent knowledge regarding medical management in pulmonary arterial hypertension (PAH).

RECENT FINDINGS

Evidence has shown that PAH patients' quality of life and prognosis depend on the capability of the RV to adapt to increased afterload and to fully recover in response to substantially reduced pulmonary vascular resistance obtained with medical therapy. Data from recent clinical studies show that more aggressive treatment strategies, especially in higher risk categories, determine larger afterload reductions, consequentially increasing the probability of achieving right heart reverse remodeling, therefore improving the patients' survival and quality of life. Remarkable progress has been observed over the past decades in the medical treatment of PAH, related to the development of drugs that target multiple biological pathways, strategies for earlier and more aggressive treatment interventions. New hopes for treatment of patients who are unable to achieve low-risk status have been derived from the phase 2 trial PULSAR and the phase 3 trial STELLAR, which show improvement in the hemodynamic status of patients treated with sotatercept on top of background therapy. Promising results are expected from several ongoing clinical trials targeting new pathways involved in the pathophysiology of PAH.

Pressure Overload and Right Ventricular Failure: From Pathophysiology to Treatment

Right ventricular failure (RVF) is often caused by increased afterload and disrupted coupling between the right ventricle (RV) and the pulmonary arteries (PAs). After a phase of adaptive hypertrophy, pressure-overloaded RVs evolve towards maladaptive hypertrophy and finally ventricular dilatation, with reduced stroke volume and systemic congestion. In this article, we review the concept of RV-PA coupling, which depicts the interaction between RV contractility and afterload, as well as the invasive and non-invasive techniques for its assessment. The current principles of RVF management based on pathophysiology and underlying etiology are subsequently discussed. Treatment strategies remain a challenge and range from fluid management and afterload reduction in moderate RVF to vasopressor therapy, inotropic support and, occasionally, mechanical circulatory support in severe RVF.

Myocardial Fibrosis in Congenital Heart Disease and the Role of MRI

Progress in the field of congenital heart surgery over the last century can only be described as revolutionary. Recent improvements in patient outcomes have been achieved through refinements in perioperative care. In the current and future eras, the preservation and restoration of myocardial health, beginning with the monitoring of tissue remodeling, will be central to improving cardiac outcomes. Visualization and quantification of fibrotic myocardial remodeling is one of the greatest assets that cardiac MRI brings to the field of cardiology, and its clinical use within the field of congenital heart disease (CHD) has been an area of particular interest in the last few decades. This review summarizes the physical underpinnings of myocardial tissue characterization in CHD, with an emphasis on T1 parametric mapping and late gadolinium enhancement. It describes methods and suggestions for obtaining images, extracting quantitative and qualitative data, and interpreting the results for children and adults with CHD. The tissue characterization observed in different lesions is used to examine the causes and pathomechanisms of fibrotic remodeling in this population. Similarly, the clinical consequences of elevated imaging biomarkers of fibrosis on patient health and outcomes are explored. Keywords: Pediatrics, MR Imaging, Cardiac, Heart, Congenital, Tissue Characterization, Congenital Heart Disease, Cardiac MRI, Parametric Mapping, Fibrosis, Late Gadolinium Enhancement © RSNA, 2023.

Functional and molecular determinants of right ventricular response to severe pulmonary hypertension in a large animal model

Right ventricular (RV) failure is the major determinant of outcome in pulmonary hypertension (PH). Calves exposed to 2-wk hypoxia develop severe PH and unlike rodents, hypoxia-induced PH in this species can lead to right heart failure. We, therefore, sought to examine the molecular and structural changes in the RV in calves with hypoxia-induced PH, hypothesizing that we could identify mechanisms underlying compensated physiological function in the face of developing severe PH. Calves were exposed to 14 days of environmental hypoxia (equivalent to 4,570 m/15,000 ft elevation, n = 29) or ambient normoxia (1,525 m/5,000 ft, n = 25). Cardiopulmonary function was evaluated by right heart catheterization and pressure volume loops. Molecular and cellular determinants of RV remodeling were analyzed by cDNA microarrays, RealTime PCR, proteomics, and immunochemistry. Hypoxic exposure induced robust PH, with increased RV contractile performance and preserved cardiac output, yet evidence of dysregulated RV-pulmonary artery mechanical coupling as seen in advanced disease. Analysis of gene expression revealed cellular processes associated with structural remodeling, cell signaling, and survival. We further identified specific clusters of gene expression associated with 1) hypertrophic gene expression and prosurvival mechanotransduction through YAP-TAZ signaling, 2) extracellular matrix (ECM) remodeling, 3) inflammatory cell activation, and 4) angiogenesis. A potential transcriptomic signature of cardiac fibroblasts in RV remodeling was detected, enriched in functions related to cell movement, tissue differentiation, and angiogenesis. Proteomic and immunohistochemical analysis confirmed RV myocyte hypertrophy, together with localization of ECM remodeling, inflammatory cell activation, and endothelial cell proliferation within the RV interstitium. In conclusion, hypoxia and hemodynamic load initiate coordinated processes of protective and compensatory RV remodeling to withstand the progression of PH.NEW & NOTEWORTHY Using a large animal model and employing a comprehensive approach integrating hemodynamic, transcriptomic, proteomic, and immunohistochemical analyses, we examined the early (2 wk) effects of severe PH on the RV. We observed that RV remodeling during PH progression represents a continuum of transcriptionally driven processes whereby cardiac myocytes, fibroblasts, endothelial cells, and proremodeling macrophages act to coordinately maintain physiological homeostasis and protect myocyte survival during chronic, severe, and progressive pressure overload.

Jiedu Quyu Decoction mitigates monocrotaline-induced right-sided heart failure associated with pulmonary artery hypertension by inhibiting NLRP3 inflammasome in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Right-side heart failure could accelerate mortality in patients of pulmonary hypertension, Jiedu Quyu Decoction (JDQYF) was used to manage pulmonary hypertension, but its right-sided heart protective effect associated with pulmonary artery hypertension is still unclear.

AIM OF THE STUDY

Here, we evaluated the therapeutic effect of JDQYF on monocrotaline-induced right-sided heart failure associated with pulmonary arterial hypertension in Sprague-Dawley (SD) rats and investigated the potential mechanism of action.

MATERIALS AND METHODS

The main chemical components of JDQYF were detected and analyzed using ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry. The effects of JDQYF were investigated using a rat model of monocrotaline-induced right-sided heart failure associated with pulmonary arterial hypertension. We assessed the morphology of cardiac tissue using histopathology and the structure and function of the right heart using echocardiography. The biomarkers of heart failure, atrial natriuretic peptide and B-type natriuretic peptide, as well as serum pro-inflammatory markers, interleukin (IL)-1β, and IL-18, were measured by enzyme-linked immunosorbent assay (ELISA). Furthermore, the mRNA and protein expression levels of NLRP3 (NOD-, LRR-, and pyrin domain-containing 3), capase-1, IL-1β, and IL-18 in the right heart tissue were examined by real-time quantitative reverse transcription PCR and western blotting.

RESULTS

JDQYF improved ventricular function, alleviated pathological lesions in the right cardiac tissue, reduced the expression levels of biomarkers of heart failure and serum pro-inflammatory factors (IL-1β and IL-18), and downregulated the mRNA and protein expression levels of NLRP3, caspase-1, IL-1β, and IL-18 in the right cardiac tissue.

CONCLUSIONS

JDQYF possesses cardioprotective effect against right heart failure induced by pulmonary arterial hypertension, possibly owing to reduction of cardiac inflammation through the inhibition of NLRP3 inflammasome activation.

Differences in right ventricular function and response to targeted therapy between patients with IPAH and PAH-CHD

Background and aims: Pulmonary arterial hypertension (PAH) is a chronic pulmonary vascular disorder characterized by elevated pulmonary vascular resistance (PVR) and pulmonary arterial pressure (PAP). Right heart failure is a life-threatening complication of PAH and predicts a poor prognosis. PAH associated with congenital heart disease (PAH-CHD) and idiopathic PAH (IPAH) are two prevalent PAH subtypes in China. In this section, we set out to explore baseline right ventricular (RV) function and its response to targeted agents between IPAH and PAH-CHD. Methods and results: Consecutive patients diagnosed with IPAH or PAH-CHD by right heart catheterization (RHC) in the Second Xiangya Hospital from November 2011 to June 2020 were included. All patients received PAH-targeted therapy and the RV function was assessed by echocardiography at baseline and during follow-up. A total of 303 patients (age, 36.23 ± 13.10 years; women, 213 (70.3%); mean PAP [mPAP], 63.54 ± 16.12 mmHg; PVR, 14.74 ± 7.61 WU) with IPAH (n = 121) or PAH-CHD (n = 182) were included in this study. Compared with PAH-CHD, patients with IPAH had worse baseline RV function. As of the latest follow-up, forty-nine patients with IPAH and six patients with PAH-CHD died. Kaplan-Meier analyses showed better survival in PAH-CHD versus IPAH. After PAH-targeted therapy, patients with IPAH had less improvement in 6 MWD, World Health Organization functional class, and RV functional parameters compared with patients with PAH-CHD. Conclusion: Compared with patients with PAH-CHD, patients with IPAH had worse baseline RV function, unfavourable prognosis, and inadequate response to targeted treatment.

Xinyang Tablet attenuates chronic hypoxia-induced right ventricular remodeling via inhibiting cardiomyocytes apoptosis

BACKGROUND

Hypoxia-induced pulmonary hypertension (HPH) is one of the fatal pathologies developed under hypobaric hypoxia and eventually leads to right ventricular (RV) remodeling and RV failure. Clinically, the mortality rate of RV failure caused by HPH is high and lacks effective drugs. Xinyang Tablet (XYT), a traditional Chinese medicine exhibits significant efficacy in the treatment of congestive heart failure and cardiac dysfunction. However, the effects of XYT on chronic hypoxia-induced RV failure are not clear.

METHODS

The content of XYT was analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS). Sprague-Dawley (SD) rats were housed in a hypobaric chamber (equal to the parameter in altitude 5500 m) for 21 days to obtain the RV remodeling model. Electrocardiogram (ECG) and hemodynamic parameters were measured by iWorx Acquisition & Analysis System. Pathological morphological changes in the RV and pulmonary vessels were observed by H&E staining and Masson's trichrome staining. Myocardial apoptosis was tested by TUNEL assay. Protein expression levels of TNF-α, IL-6, Bax, Bcl-2, and caspase-3 in the RV and H9c2 cells were detected by western blot. Meanwhile, H9c2 cells were induced by CoCl₂ to establish a hypoxia injury model to verify the protective effect and mechanisms of XYT. A CCK-8 assay was performed to determine the viability of H9c2 cells. CoCl₂-induced apoptosis was detected by Annexin-FITC/PI flow cytometry and Hoechst 33,258 staining.

RESULTS

XYT remarkably improved RV hemodynamic disorder and ECG parameters. XYT attenuated hypoxia-induced pathological injury in RV and pulmonary vessels. We also observed that XYT treatment decreased the expression levels of TNF-α, IL-6, Bax/Bcl-2 ratio, and the numbers of myocardial apoptosis in RV. In H9c2 myocardial hypoxia model, XYT protected H9c2 cells against Cobalt chloride (CoCl₂)-induced apoptosis. We also found that XYT could antagonize CoCl₂-induced apoptosis through upregulating Bcl-2, inhibiting Bax and caspase-3 expression.

CONCLUSIONS

We concluded that XYT improved hypoxia-induced RV remodeling and protected against cardiac injury by inhibiting apoptosis pathway in vivo and vitro models, which may be a promising therapeutic strategy for clinical management of hypoxia-induced cardiac injury.

Computational modelling of multi-temporal ventricular-vascular interactions during the progression of pulmonary arterial hypertension

A computational framework is developed to consider the concurrent growth and remodelling (G&R) processes occurring in the large pulmonary artery (PA) and right ventricle (RV), as well as ventricular-vascular interactions during the progression of pulmonary arterial hypertension (PAH). This computational framework couples the RV and the proximal PA in a closed-loop circulatory system that operates in a short timescale of a cardiac cycle, and evolves over a long timescale due to G&R processes in the PA and RV. The framework predicts changes in haemodynamics (e.g. 68.2% increase in mean PA pressure), RV geometry (e.g. 38% increase in RV end-diastolic volume) and PA tissue microstructure (e.g. 90% increase in collagen mass) that are consistent with clinical and experimental measurements of PAH. The framework also predicts that a reduction in RV contractility is associated with long-term RV chamber dilation, a common biomarker observed in the late-stage PAH. Sensitivity analyses on the G&R rate constants show that large PA stiffening (both short and long term) is affected by RV remodelling more than the reverse. This framework can serve as a foundation for the future development of a more predictive and comprehensive cardiovascular G&R model with realistic heart and vascular geometries.

The Right Ventricle: From Embryologic Development to RV Failure

PURPOSE OF REVIEW

The right ventricle (RV) and left ventricle (LV) have different developmental origins, which likely plays a role in their chamber-specific response to physiological and pathological stress. RV dysfunction is encountered frequently in patients with congenital heart disease (CHD) and right heart abnormalities emerge from different causes than increased afterload alone as is observed in RV dysfunction due to pulmonary hypertension (PH). In this review, we describe the developmental, structural, and functional differences between ventricles while highlighting emerging therapies for RV dysfunction.

RECENT FINDINGS

There are new insights into the role of fibrosis, inflammation, myocyte contraction, and mitochondrial dynamics in the pathogenesis of RV dysfunction. We discuss the current state of therapies that may potentially improve RV function in both experimental and clinical trials. A clearer understanding of the differences in molecular alterations in the RV compared to the LV may allow for the development of better therapies that treat RV dysfunction.

Utility of the tricuspid annular tissue doppler systolic velocity and pulmonary artery systolic pressure relationship in right ventricular systolic function assessment: A pilot study

BACKGROUND

Tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP) ratio has been validated as a valuable noninvasive measure of right ventricular (RV) elastance and systolic function. However, the more reliable TA systolic (s') velocity measure of RV systolic function compared to TAPSE has not been previously studied.

METHODS

We conducted a pilot study using several variables of RV function in 50 patients with the main aim to determine which numerical expression between TA TDI s'/PASP and TAPSE/PASP ratio was most useful.

RESULTS

In a stepwise multiple regression analysis, TA TDI s'/PASP ratio (p < .0002); LVOT VTI/RVOT VTI ratio (p < .0002); RVOT VTI (p < .0047); TAPSE/PASP ratio (p < .0259) and TA TDI e' (p < .0292) were best in discriminating normal versus abnormal RV systolic function. Using receiver operator curve analysis, cut-off values for both TA TDI s'/PASP (>3.9 mm/c/mmHg) had 82.1% sensitivity and 77.3% specificity while the TAPSE/PASP (>.61 mm/mmHg) had 89.3% sensitivity and 68.2% specificity in identifying normal RV function in our studied population.

CONCLUSION

Our results indicate that TA TDI s'/PASP is a better mathematical expression when examining the relationship between RV contractility and RV resistance relationship. Furthermore, we also found that inclusion of RVOT VTI, RV diastolic properties, and left ventricular systolic function are important determinants of RV systolic function assessments and should be routinely included. Additional prospective studies are now needed to confirm these results using hemodynamic data.

Identification of LTBP-2 as a plasma biomarker for right ventricular dysfunction in human pulmonary arterial hypertension

Although right ventricular (RV) function is the primary determinant of morbidity and mortality in pulmonary arterial hypertension (PAH), the molecular mechanisms of RV remodeling and the circulating factors reflecting its function remain largely elusive. In this context, the identification of new molecular players implicated in maladaptive RV remodeling along with the optimization of risk stratification approaches in PAH are key priorities. Through combination of transcriptomic and proteomic profiling of RV tissues with plasma proteome profiling, we identified a panel of proteins, mainly related to cardiac fibrosis, similarly upregulated in the RV and plasma of patients with PAH with decompensated RV. Among these, we demonstrated that plasma latent transforming growth factor beta binding protein 2 (LTBP-2) level correlates with RV function in human PAH and adds incremental value to current risk stratification models to predict long-term survival in two independent PAH cohorts.

Lack of right ventricular hypertrophy is associated with right heart failure in patients with left ventricular failure

Presence of right heart failure (RHF) is associated with a worse prognosis in patients with left ventricular failure (LVF). While the cause of RHF secondary to LVF is multifactorial, an increased right ventricular (RV) afterload is believed as the major cause of RHF. However, data are scarce on the adaptive responses of the RV in patients with LVF. Our aim was to understand the relationship of right ventricular hypertrophy (RVH) with RHF and RV systolic and diastolic properties in patients with LVF. 55 patients with a left ventricular ejection fraction of 40% or less were included in the present study. A comprehensive two-dimensional transthoracic echocardiographic examination was done to all participants. 12 patients (21.8%) had RHF, and patients with RHF had a significantly lower right ventricular free wall thickness (RVFWT) as compared to patients without RHF (5.3 ± 1.7 mm vs. 6.6 ± 0.9 mm, p = 0.02) and the difference remained statistically significant after adjusting for confounders (Δx̅:1.34 mm, p = 0.002). RVFWT had a statistically significant correlation with tricuspid annular plane systolic excursion (r = 0.479, p < 0.001) and tricuspid annular lateral systolic velocity (r = 0.360, p = 0.007), but not with the indices of the RV diastolic function. None of the patients with concentric RVH had RHF, while 22.2% of patients with eccentric RVH and 66.7% of patients without RVH had RHF (p < 0.01 as compared to patients with concentric RVH). In patients with left ventricular systolic dysfunction, absence of RVH was associated with worse RV systolic performance and a significantly higher incidence of RHF.

Proteasome Inhibitors Decrease the Viability of Pulmonary Arterial Smooth Muscle Cells by Restoring Mitofusin-2 Expression under Hypoxic Conditions

Pulmonary hypertension (PH) is a severe progressive disease, and the uncontrolled proliferation of pulmonary artery smooth muscle cells (PASMCs) is one of the main causes. Mitofusin-2 (MFN2) profoundly inhibits cell growth and proliferation in a variety of tumor cell lines and rat vascular smooth muscle cells. Down-regulation of MFN2 is known to contribute to PH. Proteasome inhibitors have been shown to inhibit the proliferation of PASMCs; however, there is no study on the regulation of proteasome inhibitors through MFN-2 in the proliferation of PASMCs, a main pathophysiology of PH. In this study, PASMCs were exposed to hypoxic conditions and the expression of MFN2 and cleaved-PARP1 were detected by Western blotting. The effects of hypoxia and proteasome inhibitors on the cell viability of PASMC cells were detected by CCK8 assay. The results indicated that hypoxia increases the viability and reduces the expression of MFN2 in a PASMCs model. MFN2 overexpression inhibits the hypoxia-induced proliferation of PASMCs. In addition, proteasome inhibitors, bortezomib and marizomib, restored the decreased expression of MFN2 under hypoxic conditions, inhibited hypoxia-induced proliferation and induced the expression of cleaved-PARP1. These results suggest that bortezomib and marizomib have the potential to improve the hypoxia-induced proliferation of PASMCs by restoring MFN2 expression.

PARP1-PKM2 Axis Mediates Right Ventricular Failure Associated With Pulmonary Arterial Hypertension

The authors show that increased poly(adenosine diphosphate-ribose) polymerase 1 (PARP1) and pyruvate kinase muscle isozyme 2 (PKM2) expression is a common feature of a decompensated right ventricle in patients with pulmonary arterial hypertension and animal models. The authors find in vitro that overactivated PARP1 promotes cardiomyocyte dysfunction by favoring PKM2 expression and nuclear function, glycolytic gene expression, activation of nuclear factor κB-dependent proinflammatory factors. Pharmacologic and genetic inhibition of PARP1 or enforced tetramerization of PKM2 attenuates maladaptive remodeling improving right ventricular (RV) function in multiple rodent models. Taken together, these data implicate the PARP1/PKM2 axis as a critical driver of maladaptive RV remodeling and a new promising target to directly sustain RV function in patients with pulmonary arterial hypertension.

Application and Validation of the Tricuspid Annular Plane Systolic Excursion/Systolic Pulmonary Artery Pressure Ratio in Patients with Ischemic and Non-Ischemic Cardiomyopathy

The main aim of this study was to assess the prognostic utility of TAPSE/PASP as an echocardiographic parameter of maladaptive RV remodeling in cardiomyopathy patients using cardiac magnetic resonance (CMR) imaging. Furthermore, we sought to compare TAPSE/PASP to TAPSE. The association of the echocardiographic parameters TAPSE/PASP and TAPSE with CMR parameters of RV and LV remodeling was evaluated in 111 patients with ischemic and non-ischemic cardiomyopathy and cut-off values for maladaptive RV remodeling were defined. In a second step, the prognostic value of TAPSE/PASP and its cut-off value were analyzed regarding mortality in a validation cohort consisting of 221 patients with ischemic and non-ischemic cardiomyopathy. A low TAPSE/PASP (<0.38 mm/mmHg) and TAPSE (<16 mm) were associated with a lower RVEF and a long-axis RV global longitudinal strain (GLS) as well as higher RVESVI, RVEDVI and NT-proBNP. A low TAPSE/PASP, but not TAPSE, was associated with a lower LVEF and long-axis LV GLS, and a higher LVESVI, LVEDVI and T1 relaxation time at the interventricular septum and the RV insertion points. Furthermore, in the validation cohort, low TAPSE/PASP was associated with a higher mortality and TAPSE/PASP was an independent predictor of mortality. TAPSE/PASP is a predictor of maladaptive RV and LV remodeling associated with poor outcomes in cardiomyopathy patients.

Pulmonary hypertension phenotypes in patients with systemic sclerosis

Pulmonary hypertension (PH) commonly affects patients with systemic sclerosis (SSc) and is associated with significant morbidity and increased mortality. PH is a heterogenous condition and several different forms can be associated with SSc, including pulmonary arterial hypertension (PAH) resulting from a pulmonary arterial vasculopathy, PH due to left heart disease and PH due to interstitial lung disease. The incidence of pulmonary veno-occlusive disease is also increased. Accurate and early diagnosis to allow optimal treatment is, therefore, essential. Recent changes to diagnostic haemodynamic criteria at the 6th World Symposium on Pulmonary Hypertension have resulted in therapeutic uncertainty regarding patients with borderline pulmonary haemodynamics. Furthermore, the optimal pulmonary vascular resistance threshold for diagnosing PAH and the role of exercise in identifying early disease require further elucidation. In this article we review the epidemiology, diagnosis, outcomes and treatment of the spectrum of pulmonary vascular phenotypes associated with SSc.

Mineralocorticoid receptors in pulmonary hypertension and right heart failure: From molecular biology to therapeutic targeting

Pulmonary hypertension (PH) is a devastating condition characterized by pulmonary vascular remodelling, leading to progressive increase in pulmonary artery pressure and subsequent right ventricular failure. Aldosterone and the mineralocorticoid receptor (MR), a nuclear transcription factor, are key drivers of cardiovascular disease and MR antagonists are well-established in heart failure. Now, a growing body of evidence points at a detrimental role of MR in PH. Pharmacological MR blockade attenuated PH and prevented RV failure in experimental models. Mouse models with cell selective MR deletion suggest that this effect is mediated by MR in endothelial cells. While the evidence from experimental studies appears convincing, the available clinical data on MR antagonist use in patients with PH is more controversial. Integrated analysis of clinical data together with MR-dependent molecular alterations may provide insights why some patients respond to MRA treatment while others do not. Potential ways to identify MRA 'responders' include the analysis of underlying PH causes, stage of disease, or sex, as well as new biomarkers.

Analysis of right ventricular flow with 4-dimensional flow cardiovascular magnetic resonance imaging in patients with pulmonary arterial hypertension

Background

Cardiac flow closely interact with function, however, the correlation of right ventricular (RV) flow and function remains unknown, thus our objective is to observe right ventricular flow with four-dimensional phase-contrast cardiovascular magnetic resonance imaging (4D flow CMR) in patients with pulmonary arterial hypertension (PAH) and to analyze flow components with RV function and hemodynamics.

Methods

This study retrospectively enrolled 30 patients with PAH (mean age: 49±13 years, 16 females) and 14 age- and sex-matched healthy volunteers as controls (mean age: 44±12 years, 9 females). All patients who underwent CMR and right heart catheterization (RHC) within 1 week between January 2019 and July 2020 were included. Hemodynamics were measured with RHC. RV flow components, including the percentages of direct flow (RVPDF), retained inflow (RVPRI), delayed ejection flow (RVPDEF) and residual volume (RVPRVo) were quantified using 4D flow CMR. The associations between RV flow components and other CMR metrics, clinical data, and hemodynamics were analyzed by Spearman's correlation analysis.

Results

In patients with PAH, RVPDF was decreased and RVPRVo was increased compared with the normal control group. The sum of RVPDF and RVPDEF RV was significantly correlated with RV ejection fraction (RVEF) (r=0.802, P<0.001), and there was no notable difference between RVEF and the sum of RVPDF and RVPDEF (t=0.251, P=0.831). Both RVPDF and RVPRVo were correlated (in opposite directions) with the RV end-diastolic volume index, RV end-systolic volume index, RV global longitudinal strain, and RVEF. RVPDF was negatively correlated with pulmonary vascular resistance (PVR), and positively correlated with cardiac output and cardiac index. RVPRVo was positively correlated with PVR and negatively correlated with cardiac output and cardiac index.

Conclusions

RV blood flow components qualified with 4D flow CMR is a valuable noninvasive method for the assessment of RV function and hemodynamics in patients with PAH.

Osteopontin and galectin-3 as biomarkers of maladaptive right ventricular remodeling in pulmonary hypertension

Aim: This study assessed the utility of osteopontin (OPN) and galectin-3 (Gal-3) as biomarkers of maladaptive right ventricular remodeling in pulmonary hypertension (PH). Materials & methods: We examined plasma levels of OPN and Gal-3 in patients with PH (n = 62), dilated cardiomyopathy (n = 34), left ventricular hypertrophy (LVH; n = 47), and controls without right ventricle (RV) or LV abnormalities (n = 38). Results: OPN and Gal-3 levels were higher in PH, dilated cardiomyopathy and LVH than in the controls. OPN concentrations in PH patients with maladaptive RV were significantly higher than in those with adaptive RV. Gal-3 did not differentiate between adaptive and maladaptive RV remodeling in PH. OPN and Gal-3 levels did not correlate with parameters of LV remodeling. Conclusion: OPN is a potential biomarker of RV maladaptation.

Critical Care Management of the Patient with Pulmonary Hypertension

Pulmonary hypertension patients admitted to the intensive care unit have high mortality, and right ventricular failure typically is implicated as cause of or contributor to death. Initial care of critically ill pulmonary hypertension patients includes recognition of right ventricular failure, appropriate monitoring, and identification and treatment of any inciting cause. Management centers around optimization of cardiac function, with a multipronged approach aimed at reversing the pathophysiology of right ventricular failure. For patients who remain critically ill or in shock despite medical optimization, mechanical circulatory support can be used as a bridge to recovery or lung transplantation.

Echocardiographic Prognosis Relevance of Attenuated Right Heart Remodeling in Idiopathic Pulmonary Arterial Hypertension

Background: Right ventricular (RV) function is a great determination of the fate in patients with pulmonary arterial hypertension (PAH). Monitoring RV structure back to normal or improvement should be useful for evaluation of RV function. The aims of this study were to assess the prognostic relevance of changed right heart (RH) dimensions by echocardiography and attenuated RH remodeling (ARHR) in idiopathic PAH (IPAH).

Methods: We retrospectively analyzed 232 consecutive adult IPAH patients at baseline assessment and included RH catheterization and echocardiography. ARHR at the mean 20 ± 12 months' follow-up was defined by a decreased right atrium area, RV mid-diameter, and left ventricular end-diastolic eccentricity index. The follow-up end point was all-cause mortality.

Results: At mean 20 ± 12 months' follow-up, 33 of 232 patients (14.2%) presented with ARHR. The remaining 199 surviving patients were monitored for another 25 ± 20 months. At the end of follow-up, the survival rates at 1, 3, and 5 years were 89, 89, and 68% in patients with ARHR, respectively, and 84, 65 and 41% in patients without ARHR (log-rank p = 0.01). ARHR was an independent prognostic factor for mortality. Besides, ARHR was available to further stratify patients' risk assessment through the French PAH non-invasive-risk criteria.

Conclusions: Echocardiographic ARHR is an independent determinant of prognosis in IPAH at long-term follow-up. ARHR might be a useful tool to indicate the RV morphologic and functional improvement associated with better prognostic likelihood.

Physiology of the Right Ventricle Across the Lifespan

The most common cause of heart failure in the United States is ischemic left heart disease; accordingly, a vast amount of work has been done to elucidate the molecular mechanisms underlying pathologies of the left ventricle (LV) as a general model of heart failure. Until recently, little attention has been paid to the right ventricle (RV) and it has commonly been thought that the mechanical and biochemical properties of the RV are similar to those of the LV. However, therapies used to treat LV failure often fail to improve ventricular function in RV failure underscoring, the need to better understand the unique physiologic and pathophysiologic properties of the RV. Importantly, hemodynamic stresses (such as pressure overload) often underlie right heart failure further differentiating RV failure as unique from LV failure. There are significant structural, mechanical, and biochemical properties distinctive to the RV that influences its function and it is likely that adaptations of the RV occur uniquely across the lifespan. We have previously reviewed the adult RV compared to the LV but there is little known about differences in the pediatric or aged RV. Accordingly, in this mini-review, we will examine the subtle distinctions between the RV and LV that are maintained physiologically across the lifespan and will highlight significant knowledge gaps in our understanding of pediatric and aging RV. Consideration of how RV function is altered in different disease states in an age-specific manner may enable us to define RV function in health and importantly, in response to pathology.

RNA expression profiles and regulatory networks in human right ventricular hypertrophy due to high pressure load

Right ventricular hypertrophy (RVH) occurs in high pressure afterload, e.g., tetralogy of Fallot/pulmonary stenosis (TOF/PS). Such RVH is associated with alterations in energy metabolism, neurohormonal and epigenetic dysregulation (e.g., microRNA), and fetal gene reprogramming in animal models. However, comprehensive expression profiling of competing endogenous RNA in human RVH has not been performed. Here, we unravel several previously unknown circular, long non-coding, and microRNAs, predicted to regulate expression of genes specific to human RVH in the non-failing heart (TOF/PS). These genes are significantly overrepresented in pathways related to regulation of glucose and lipid metabolism (SIK1, FABP4), cell surface interactions (THBS2, FN1), apoptosis (PIK3IP1, SIK1), extracellular matrix composition (CTGF, IGF1), and other biological events. This is the first unbiased RNA sequencing study of human compensated RVH encompassing coding and non-coding RNA expression and predicted sponging of miRNAs by non-coding RNAs. These findings advance our understanding of adaptive RVH and highlight future therapeutic targets.

•

First comprehensive transcriptomic study of human RVH via RNA expression and network analysis

•

First human RVH study using exclusively freshly isolated myocardium

•

Known hypertrophy genes are regulated the strongest by competing endogenous RNA networks in RVH

•

Epigenetic mRNA regulation in RVH by ncRNAs is dependent on sex and age

Autologous skeletal myoblast patch implantation prevents the deterioration of myocardial ischemia and right heart dysfunction in a pressure-overloaded right heart porcine model

Right ventricular dysfunction is a predictor for worse outcomes in patients with congenital heart disease. Myocardial ischemia is primarily associated with right ventricular dysfunction in patients with congenital heart disease and may be a therapeutic target for right ventricular dysfunction. Previously, autologous skeletal myoblast patch therapy showed an angiogenic effect for left ventricular dysfunction through cytokine paracrine effects; however, its efficacy in right ventricular dysfunction has not been evaluated. Thus, this study aimed to evaluate the angiogenic effect of autologous skeletal myoblast patch therapy and amelioration of metabolic and functional dysfunction, in a pressure-overloaded right heart porcine model. Pulmonary artery stenosis was induced by a vascular occluder in minipigs; after two months, autologous skeletal myoblast patch implantation on the right ventricular free wall was performed (n = 6). The control minipigs underwent a sham operation (n = 6). The autologous skeletal myoblast patch therapy alleviated right ventricular dilatation and ameliorated right ventricular systolic and diastolic dysfunction. 11C-acetate kinetic analysis using positron emission tomography showed improvement in myocardial oxidative metabolism and myocardial flow reserve after cell patch implantation. On histopathology, a higher capillary density and vascular maturity with reduction of myocardial ischemia were observed after patch implantation. Furthermore, analysis of mRNA expression revealed that the angiogenic markers were upregulated, and ischemic markers were downregulated after patch implantation. Thus, autologous skeletal myoblast patch therapy ameliorated metabolic and functional dysfunction in a pressure-overloaded right heart porcine model, by alleviating myocardial ischemia through angiogenesis.

Effects of chronic moderate alcohol consumption on right ventricle and pulmonary remodelling

NEW FINDINGS

What is the central question of this study? Does the consumption of a moderate amount of alcohol differentially impact the heart ventricles and pulmonary vasculature. What is the main finding and its importance? Moderate alcohol consumption for a short period of time impaired pulmonary vascular cellular renewal through an apoptosis resistance pattern that ultimately affected the right ventricular function and structure. These findings support the need for a deeper understanding of effects of moderate alcohol consumption on the overall cardiovascular and pulmonary systems.

ABSTRACT

Over the past decades, observational studies have supported an association between moderate alcohol consumption and a lower risk of cardiovascular disease and mortality. However, recent and more robust meta-analyses have raised concerns around the robustness of the evidence for the cardioprotective effects of alcohol. Also, studies of the functional, structural and molecular changes promoted by alcohol have focused primarily on the left ventricle, ignoring the fact that the right ventricle could adapt differently. The aim of this study was to evaluate the bi-ventricular impact of daily moderate alcohol intake, during a 4-week period, in a rodent model. Male Wistar rats were allowed to drink water (Control) or a 5.2% ethanol mixture (ETOH) for 4 weeks. At the end of the protocol bi-ventricular haemodynamic recordings were performed and samples collected for further histological and molecular analysis. ETOH ingestion did not impact cardiac function. However, it caused right ventricle hypertrophy, paralleled by an activation of molecular pathways responsible for cell growth (ERK1/2, AKT), proteolysis (MURF-1) and oxidative stress (NOX4, SOD2). Furthermore, ETOH animals also presented remodelling of the pulmonary vasculature with an increase in pulmonary arteries' medial thickness, which was characterized by increased expression of apoptosis-related proteins expression (BCL-XL, BAX and caspases). Moderate alcohol consumption for a short period of time impaired the lungs and the right ventricle early, before any change could be detected on the left ventricle. Right ventricular changes might be secondary to alcohol-induced pulmonary vasculature remodelling.

The Growing Role of Echocardiography in Pulmonary Arterial Hypertension Risk Stratification: The Missing Piece

Pulmonary arterial hypertension (PAH) is a rare, progressive disease with a poor prognosis. The pathophysiologic model is mainly characterized by an afterload mismatch in which an increased right ventricle afterload, driven by increased pulmonary vascular resistance (PVR), leads to right heart failure. International guidelines recommend optimization of treatment based on regular risk assessments to achieve or maintain a low-risk status. Current risk scores are based on a multi-modality approach, including demographic, clinical, functional, exercise, laboratory, and hemodynamic parameters, which lack significant echocardiographic parameters. The originality of echocardiography relies on the opportunity to assess in a non-invasive way a physiologically meaningful combination of easy to measure variables tightly related to right ventricle adaptation/maladaptation to increased afterload, the main determinant of a patient's prognosis. Echo-derived morphological and functional parameters have been investigated in PAH, proving to have prognostic relevance. Different therapeutic strategies proved to have different effects in reducing PVR. An upfront combination of drugs, including a parenteral prostacyclin, has shown to be associated with right heart reverse remodeling in a greater proportion of patients than other treatment strategies as a function of PVR reduction. Adding echocardiographic data to current risk scores would allow better identification of right ventricle (RV) adaptation in PAH patients' follow-up. This additional information would allow better stratification of the patient, leading to optimized and personalized therapeutic management.

Neuropeptide Y Induces Cardiomyocyte Hypertrophy via Attenuating miR-29a-3p in Neonatal Rat Cardiomyocytes

BACKGROUND

Neuropeptide Y (NPY) has been well known to induce Cardiomyocyte Hypertrophy (CH), which is possibly caused by disruption of cardiac cell energy balance. As mitochondria is losely related to energy metabolism, in this study, we investigated the changes in mitochondrial Dynamics-related protein (Drp1) expression under the action of NPY. miRNA-29a, a endogenous noncoding small molecule RNA which is involved in many cardiac diseases, by using a bioinformatics tool, we found a potential binding site of miRNA-29a on the Drp1 mRNA, and suggesting that miRNA-29a might play a regulatory role.

OBJECTIVE

To investigate the role of miR-29a-3p in the process of NPY-induced CH, and further explore it's predicted relationship with Drp1.

METHODS

The expression levels of miR-29a-3p and Atrial Natriuretic Peptide (ANP) were performed by the method of fluorescence quantitative PCR, in addition, expression of Drp1 in treated and control groups were performed by western blot analysis.] Results: We found NPY leads to the CH and up-regulation of ANP expression levels. We also found significant up-regulation of Drp1 expression and down-regulation of miR-29a-3p expression in NPY-treated cells. The decrease in miR-29a-3p expression may lead the increase expression level of Drp1. We found that the expression of ANP increased after NPY treatment. When Drp1 protein was silenced, the high expression of ANP was inhibited.

CONCLUSION

In this study, we found up-regulation of Drp1 in cells treated with NPY. Drp1 mRNA is a predicted target for miR-29a-3p, and the expression of Drp1 was attenuated by miR-29a-3p. Therefore, NPY leads to down-regulation of miR-29a-3p expression, up-regulation of Drp1 expression, and NPY leads to CH. Correspondingly, miR-29a-3p can counteract the effects of NPY. This may be a new way, which could be used in diagnosis and treatment plan for CH.

Patient-Specific Computational Analysis of Hemodynamics and Wall Mechanics and Their Interactions in Pulmonary Arterial Hypertension

Vascular wall stiffness and hemodynamic parameters are potential biomechanical markers for detecting pulmonary arterial hypertension (PAH). Previous computational analyses, however, have not considered the interaction between blood flow and wall deformation. Here, we applied an established computational framework that utilizes patient-specific measurements of hemodynamics and wall deformation to analyze the coupled fluid-vessel wall interaction in the proximal pulmonary arteries (PA) of six PAH patients and five control subjects. Specifically, we quantified the linearized stiffness (E), relative area change (RAC), diastolic diameter (D), regurgitant flow, and time-averaged wall shear stress (TAWSS) of the proximal PA, as well as the total arterial resistance (R t ) and compliance (C t ) at the distal pulmonary vasculature. Results found that the average proximal PA was stiffer [median: 297 kPa, interquartile range (IQR): 202 kPa vs. median: 75 kPa, IQR: 5 kPa; P = 0.007] with a larger diameter (median: 32 mm, IQR: 5.25 mm vs. median: 25 mm, IQR: 2 mm; P = 0.015) and a reduced RAC (median: 0.22, IQR: 0.10 vs. median: 0.42, IQR: 0.04; P = 0.004) in PAH compared to our control group. Also, higher total resistance (R t ; median: 6.89 mmHg × min/l, IQR: 2.16 mmHg × min/l vs. median: 3.99 mmHg × min/l, IQR: 1.15 mmHg × min/l; P = 0.002) and lower total compliance (C t ; median: 0.13 ml/mmHg, IQR: 0.15 ml/mmHg vs. median: 0.85 ml/mmHg, IQR: 0.51 ml/mmHg; P = 0.041) were observed in the PAH group. Furthermore, lower TAWSS values were seen at the main PA arteries (MPAs) of PAH patients (median: 0.81 Pa, IQR: 0.47 Pa vs. median: 1.56 Pa, IQR: 0.89 Pa; P = 0.026) compared to controls. Correlation analysis within the PAH group found that E was directly correlated to the PA regurgitant flow (r = 0.84, P = 0.018) and inversely related to TAWSS (r = -0.72, P = 0.051). Results suggest that the estimated elastic modulus E may be closely related to PAH hemodynamic changes in pulmonary arteries.

Oxygen Enrichment Ameliorates Cardiorespiratory Alterations Induced by Chronic High-Altitude Hypoxia in Rats

Chronic high-altitude hypoxia (HAH) results in compensatory pathological adaptations, especially in the cardiorespiratory system. The oxygen enrichment technology can provide long-lasting oxygen supply and minimize oxygen toxicity, which has proven to be effective to increase oxygen saturation, decrease heart rate, and improve human exercise performance after ascending to high altitudes. Nevertheless, it remains unknown whether oxygen enrichment can resist chronic HAH-induced cardiorespiratory alterations. Thirty-six male rats were equally assigned to the normal control (NC), HAH, and HAH with oxygen enrichment (HAHO) groups. The HAH and HAHO rats were housed in a hypobaric hypoxia chamber equivalent to 5,000 m for 4 weeks. The HAHO rats were exposed to oxygen-enriched air for 8 h/day. We found that oxygen enrichment mitigated the augmented skin blood flow and improved the locomotor activity of HAH-exposed rats. Oxygen enrichment inhibited HAH-induced increase in the production of red blood cells (RBCs). The hemodynamic results showed that oxygen enrichment decreased right ventricular systolic pressure (RVSP) and mean pulmonary artery pressure (mPAP) in HAH-exposed rats. HAH-associated right ventricular hypertrophy and cardiomyocyte enlargement were ameliorated by oxygen enrichment. Oxygen enrichment inhibited HAH-induced excessive expression of cytokines associated with cardiac hypertrophy and myocardial fibrosis [angiotensin-converting enzyme (ACE)/angiotensin-converting enzyme 2 (ACE2), angiotensin II (Ang II), collagen type I alpha 1 (Col1α1), collagen type III alpha 1 (Col3α1), and hydroxyproline] in the right ventricle (RV). Oxygen enrichment inhibited medial thickening, stenosis and fibrosis of pulmonary arterioles, and cytokine expression related with fibrosis (Col1α1, Col3α1, and hydroxyproline) and pulmonary vasoconstriction [endothelin-1(ET-1)] in HAH-exposed rats. This study represents the first effort testing the efficacy of the oxygen enrichment technique on cardiopulmonary structure and function in chronic HAH animals, and we found oxygen enrichment has the capability of ameliorating chronic HAH-induced cardiopulmonary alterations.

Acute Kidney Injury After Heart Transplant: The Importance of Pulmonary Hypertension

OBJECTIVE

To determine whether relative pulmonary hypertension (PH), defined as the ratio of mean arterial pressure to mean pulmonary artery pressure, is associated with severe acute kidney injury (AKI) after heart transplant (HT).

DESIGN

An institutional review board-approved retrospective observational study.

SETTING

Tertiary care university hospital.

PARTICIPANTS

A total of 184 consecutive adult patients who underwent HT between January 2009 and December 2017 were included, and were followed up through December 2019. Using the Kidney Disease: Improving Global Outcomes classification, recipients were categorized into two groups: patients who developed stage 3 AKI (severe AKI) and those with minor or without AKI (nonsevere AKI) within seven days after transplant.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of the included patients, 83.2% developed AKI, in whom 40.8%, 19.6%, and 22.8% were stage 1, 2, and 3, respectively. With use of the multivariate logistic regression analysis, independent risk factors for stage 3 AKI post-HT included preoperative relative PH (odds ratio [OR]: 1.62, 95% confidence interval [95% CI]: 1.05-2.49, p = 0.028), central venous-to-pulmonary capillary wedge pressure ratio ≥0.86 (OR: 3.59, 95% CI: 1.13-11.43, p = 0.030), and postoperative right ventricular dysfunction (OR: 3.63, 95% CI: 1.50-8.75, p = 0.004). Conversely, preoperative estimated glomerular filtration rate (OR: 0.99, 95% CI: 0.97-1.00, p = 0.143) was not related to the development of stage 3 AKI post-HT.

CONCLUSIONS

Preoperative relative PH, central venous-to-pulmonary capillary wedge pressure ratio, and postoperative right ventricular failure by echocardiographic assessment were associated with severe AKI post-HT.

Oxidation of Ryanodine Receptors Promotes Ca2+ Leakage and Contributes to Right Ventricular Dysfunction in Pulmonary Hypertension

Right ventricular (RV) failure is a major cause of death in patients with pulmonary arterial hypertension, and the mechanism of RV failure remains unclear. While the malfunction of RyR2 (ryanodine receptor type 2) on sarcoplasmic reticulum (SR) and aberrant Ca²⁺ cycling in cardiomyocytes have been recognized in some cardiovascular diseases, their roles in RV failure secondary to pulmonary arterial hypertension require further investigation. In a monocrotaline-induced rat model of pulmonary arterial hypertension, the RV remodeling process was divided into normal, compensated, and decompensated stages according to the hemodynamic and morphological parameters. In both compensated and decompensated stages, significant diastolic SR Ca²⁺ leakage was detected along with reduced intracellular Ca²⁺ transient amplitude and SR Ca²⁺ contents in RV myocytes. RyR2 protein levels decreased progressively during the process, and the thiol oxidation proportions of RyR2 were higher in compensated and decompensated stages than in normal stage. Inhibition of RyR2 oxidation by dithiothreitol or repairing RyR2 directly by dantrolene could restore Ca²⁺ homeostasis in RV myocytes. Daily intraperitoneal injection of dantrolene delayed decompensation progression and significantly improved the survival rate of pulmonary hypertension rats in decompensated stage (79.3% versus 55.9%; P=0.026). Our findings suggest that diastolic SR Ca²⁺ leakage via oxidized RyR2 facilitates the development of RV failure. Dantrolene can inhibit diastolic SR Ca²⁺ leakage in RV cardiomyocytes, delay right cardiac dysfunction, and improve the survival of rats with pulmonary arterial hypertension.

Neonatal Heart Responds to Pressure Overload With Differential Alterations in Various Cardiomyocyte Maturation Programs That Accommodate Simultaneous Hypertrophy and Hyperplasia

Pressure overload is one of the pathophysiological conditions commonly associated with right-sided congenital heart disease (CHD). Patients suffer from this condition right after birth. However, little is known about how neonatal heart reacts to it. We have previously established a pulmonary artery banding (PAB) model in neonatal rat. Here we show that PAB accelerated transition of mononuclear cardiomyocytes into multinucleated cells to promote hypertrophic growth in neonatal heart. The elevated afterload significantly increased the mitotic activities of neonatal cardiomyocytes. Consistent with the proliferative potential, the elevated pressure overload also increased cytokinetic marker counts of cardiomyocytes. Using cardiomyocyte-specific lineage tracing, we noticed a clonal expansion of rare unlabeled cardiomyocytes in the PAB group, revealing a subgroup of cardiomyocytes with a strong capability of proliferation. In addition, PAB hearts at post-banding day 7 didn’t have the accumulation of macrophages, which is an immune response essential for neonatal heart regeneration in injury models. Transcriptomic analyses revealed that neonatal PAB induced an expression profile featuring both cardiomyocyte hypertrophy, such as highly activated translation, oxidative phosphorylation, and mitochondrial biogenesis programs etc., and immature cardiomyocyte, such as enhanced cell cycle activities and glycolytic metabolism, down-regulated cytoskeleton and ion channel gene expression, and maintenance of fetal-specific sarcomeric isoforms etc. It indicates that pressure overload has differential impacts on various cardiomyocyte maturation (CM) programs that may contribute to the concurrent cardiomyocyte hypertrophy and hyperplasia. The bivalent status of transcriptional profile highlights the plasticity of neonatal cardiomyocytes that can be exploited to adapt the postnatal environment.

The Value of Hemodynamic Measurements or Cardiac MRI in the Follow-up of Patients With Idiopathic Pulmonary Arterial Hypertension

Background

Treatment of patients with pulmonary arterial hypertension (PAH) is conventionally based on functional plus invasive measurements obtained during right heart catheterization (RHC). Whether risk assessment during repeated measurements could also be performed on the basis of imaging parameters is unclear, as a direct comparison of strategies is lacking.

Research Question

How does the predictive value of noninvasive parameters compare with that of invasive hemodynamic measurements 1 year after the diagnosis of idiopathic PAH?

Study Design and Methods

One hundred and eighteen patients with idiopathic PAH who underwent RHC and cardiac MRI (CMR) were included in this study (median time between baseline evaluation and first parameter measures, 1.0 [0.8-1.2] years). Forty-four patients died or underwent lung transplantation. Forward Cox regression analyses were done to determine the best predictive functional, hemodynamic, and/or imaging model. Patients were classified as high risk if the event occurred < 5 years after diagnosis (n = 24), whereas patients without event were classified as low risk.

Results

A prognostic model based on age, sex, and absolute values at follow-up of functional parameters (6-min walk distance) performed well (Akaike information criterion [AIC], 279; concordance, 0.67). Predictive models with only hemodynamic (right atrial pressure, mixed venous oxygen saturation; AIC, 322; concordance, 0.66) or imaging parameters (right ventricular ejection fraction; AIC, 331; concordance, 0.63) at 1 year of follow-up performed similarly. The predictive value improved when functional data were combined with either hemodynamic data (AIC, 268; concordance, 0.69) or imaging data (AIC, 273; concordance, 0.70). A model composed of functional, hemodynamic, and imaging data performed only marginally better (AIC, 266; concordance, 0.69). Finally, changes between baseline and 1-year follow-up were observed for multiple hemodynamic and CMR parameters; only a change in CMR parameters was of prognostic predictive value.

Interpretation

At 1 year of follow-up, risk assessment based on CMR is at least equal to risk assessment based on RHC. In this study, only changes in CMR, but not hemodynamic parameters, were of prognostic predictive value during the first year of follow-up.