A comprehensive echocardiographic method for risk stratification in pulmonary arterial hypertension

Prognostic Value of Serial Risk Stratification in Adult and Pediatric Pulmonary Arterial Hypertension: A Systematic Review

BACKGROUND

In pulmonary arterial hypertension, it is recommended to base therapeutic decisions on risk stratification. This systematic review aims to report the prognostic value of serial risk stratification in adult and pediatric pulmonary arterial hypertension and to explore the usability of serial risk stratification as treatment target.

METHODS AND RESULTS

Electronic databases PubMed, Embase, and Web of Science were searched up to January 30, 2023, using terms associated with pulmonary arterial hypertension, pediatric pulmonary hypertension, and risk stratification. Observational studies and clinical trials describing risk stratification at both baseline and follow-up were included. Sixty five studies were eligible for inclusion, including only 2 studies in a pediatric population. C-statistic range at baseline was 0.31 to 0.77 and improved to 0.30 to 0.91 at follow-up. In 53% of patients, risk status changed (42% improved, 12% worsened) over 168 days (interquartile range, 137-327 days; n=22 studies). The average proportion of low-risk patients increased from 18% at baseline to 36% at a median follow-up of 244 days (interquartile range, 140-365 days; n=40 studies). In placebo-controlled drug studies, risk statuses of the intervention groups improved more and worsened less compared with the placebo groups. Furthermore, a low-risk status, but also an improved risk status, at follow-up was associated with a better outcome. Similar results were found in the 2 pediatric studies.

CONCLUSIONS

Follow-up risk stratification has improved prognostic value compared with baseline risk stratification, and change in risk status between baseline and follow-up corresponded to a change in survival. These data support the use of serial risk stratification as treatment target in pulmonary arterial hypertension.

Right ventricular strain to systolic pulmonary artery pressure ratio in response to treatment of pulmonary arterial hypertension

The RVFWLS/PASP ratio, a novel surrogate for ventriculoarterial coupling, showed sensitivity to afterload-lowering treatment and the magnitude of change informed on long-term outcomes in PAH https://bit.ly/4cRtREC.

Right ventricular phenotyping in incident patients with idiopathic pulmonary arterial hypertension

BACKGROUND

Right ventricular (RV) imaging has not a definite role in risk stratification of pulmonary arterial hypertension (PAH) patients. We tested the hypothesis that echocardiography-derived phenotypes, depicting different degrees of RV remodeling and dysfunction, may provide additional prognostic information to current risk stratification tools.

METHODS

Consecutive incident PAH patients aged ≥18 years, diagnosed between January 2005 and December 2021, underwent clinical assessment, right heart catheterization, standard echocardiography. Simple echocardiographic variables were combined in order to define a priori four phenotypes representing different degrees of RV dilatation and RV-pulmonary arterial (PA) coupling: Phenotype 1 with mildy dilated right ventricle and preserved RV-PA coupling (n = 152 patients); phenotype 2 with mildly dilated right ventricle and poor RV-PA coupling (n = 143 patients); phenotype 3 with severely dilated right ventricle and preserved RV-PA coupling (n = 201 patients); phenotype 4 with severely dilated right ventricle and poor RV-PA coupling, with or without severe tricuspid regurgitation (n = 519 patients). Risk stratification was based on the European Society of Cardiology/European Respiratory Society (ESC/ERS) 3-strata model and Registry to Evaluate Early and Long-Term PAH disease Management (REVEAL) 2.0 score.

RESULTS

These phenotypes were present in all risk groups. Notably, regardless of the ESC/ERS risk stratum assigned to the patient, phenotype 4 was associated with a 2-fold increase of the odds of death (HR 2.1, 95% CI 1.6-2.8, p < 0.001), while phenotype 1 was associated with a 71% reduction in the odds of dying (HR 0.29, 95% CI 0.18-0.47, p < 0.001).

CONCLUSIONS

Echocardiography-derived phenotypes describing RV remodeling and dysfunction may provide prognostic information which is independent of and additional to the clinically defined risk in incident PAH patients.

Evidence and unresolved questions in pulmonary hypertension: Insights from the 5th French Pulmonary Hypertension Network Meeting

Pulmonary hypertension (PH) continues to present significant challenges to the medical community, both in terms of diagnosis and treatment. The advent of the updated 2022 European Society of Cardiology (ESC) and European Respiratory Society (ERS) guidelines has introduced pivotal changes that reflect the rapidly advancing understanding of this complex disease. These changes include a revised definition of PH, updates to the classification system, and treatment algorithm. While these guidelines offer a critical framework for the management of PH, they have also sparked new discussions and questions. The 5th French Pulmonary Hypertension Network Meeting (Le Kremlin-Bicêtre, France, 2023), addressed these emergent questions and fostering a deeper understanding of the disease's multifaceted nature. These discussions were not limited to theoretical advancements but extended into the practical realms of patient management, highlighting the challenges and opportunities in applying the latest guidelines to clinical practice.

New risk model by right ventricle - pulmonary arterial coupling and inferior vena cava from echocardiography in patients with conventional low-intermediate risk pulmonary artery hypertension under targeted treatment

BACKGROUND

Accurately stratifying patients with pulmonary arterial hypertension (PAH) is very important, and traditional risk scores still have internal heterogeneity. This study aimed to construct a risk stratification model that can accurately identify clinical worsening (CW) events in conventional low-intermediate risk patients with pulmonary hypertension under targeted drug treatment by using echocardiographic parameters.

METHODS

This study is a single-center, prospective study, including 105 PAH patients who underwent regular follow-up at Guangdong Provincial People's Hospital from October 2021 to April 2023. The primary endpoint was the occurrence of CW, including death, hospitalization due to pulmonary hypertension, escalation of targeted drug therapy, and worsening of PAH. The predictive value of the echocardiography-based three-strata risk model was assessed using Kaplan-Meier curves and COX regression analysis.

RESULTS

A total of 98 PAH patients were ultimately included in this study. The median follow-up duration was 26 months (range 7-28 months). The echocardiography-based three-strata model included the ratio of tricuspid annular plane systolic excursion and pulmonary artery systolic pressure (TAPSE/PASP) and inferior vena cava (IVC). The echocardiography-based three-strata model had higher diagnostic value (C-index = .76) compared to the 2022 ESC/ERS three-strata model and four-strata model (C-index = .66 and C-index = .61, respectively). PAH patients with lower TAPSE/PASP and wider IVC showed a higher CW rate compared to patients with higher TAPSE/PASP and normal IVC (HR = 15.1, 95%CI:4.4-51.9, p < .001).

CONCLUSION

The echocardiography-based three-strata model based on TAPSE/PASP and IVC can effectively improve the stratification of low-intermediate risk PAH patients under targeted treatment.

A Systematic Review of Novel Therapies of Pulmonary Arterial Hypertension

BACKGROUND

Pulmonary arterial hypertension (PAH) is a progressive, cureless disease, characterized by increased pulmonary vascular resistance and remodeling, with subsequent ventricular dilatation and failure. New therapeutic targets are being investigated for their potential roles in improving PAH patients' symptoms and reversing pulmonary vascular pathology.

METHOD

We aimed to address the available knowledge from the published randomized controlled trials (RCTs) regarding the role of Rho-kinase (ROCK) inhibitors, bone morphogenetic protein 2 (BMP2) inhibitors, estrogen inhibitors, and AMP-activated protein kinase (AMPK) activators on the PAH evaluation parameters. This systematic review (SR) was registered in the International Prospective Register of Systematic Reviews (PROSPERO) database (CDR42022340658) and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Overall, 5092 records were screened from different database and registries; 8 RCTs that met our inclusion criteria were included. The marked difference in the study designs and the variability of the selected outcome measurement tools among the studies made performing a meta-analysis impossible. However, the main findings of this SR relate to the powerful potential of the AMPK activator and the imminent antidiabetic drug metformin, and the BMP2 inhibitor sotatercept as promising PAH-modifying therapies. There is a need for long-term studies to evaluate the effect of the ROCK inhibitor fasudil and the estrogen aromatase inhibitor anastrozole in PAH patients. The role of tacrolimus in PAH is questionable. The discrepancy in the hemodynamic and clinical parameters necessitates defining cut values to predict improvement. The differences in the PAH etiologies render the judgment of the therapeutic potential of the tested drugs challenging.

CONCLUSION

Metformin and sotatercept appear as promising therapeutic drugs for PAH.

CLINICAL TRIALS REGISTRATION

This work was registered in PROSPERO (CDR42022340658).

Prognostic value of deep echocardiographic phenotyping in pulmonary arterial hypertension

Background

A novel approach to derive prognostic information from echocardiography in pulmonary arterial hypertension (PAH) is to define a phenotype of right heart function combining standard echocardiographic parameters which describe right ventricular pump function and systemic venous congestion. We tested the hypothesis that the combination of advanced strain imaging parameters could yield high prognostic accuracy.

Methods

This was a prospective observational study with a single centre derivation cohort and a second centre validation cohort. The derivation cohort included 49 naive PAH patients who underwent right heart catheterisation and echocardiographic evaluation at baseline and 4-12 months after diagnosis. The validation cohort included 83 prevalent PAH patients who underwent the same examinations at 12 months after diagnosis. We stratified the risk of the derivation cohort according to three models: Model 1, based on haemodynamic parameters; Model 2, based on standard echocardiographic parameters; and Model 3, based on advanced echocardiographic parameters. The median follow-up period was 21 months; the end point of the analysis was clinical worsening.

Results

In the derivation cohort, haemodynamic and echocardiographic parameters obtained at diagnosis were not associated with outcome, whereas a significant association was observed at first reassessment. Model 3 yielded a better predictive accuracy (Harrell's C index 0.832) as compared to Model 2 (Harrell's C index 0.667), and to Model 1 (Harrell's C index 0.713). The validation cohort confirmed the accuracy of Model 3.

Conclusions

A comprehensive assessment of right heart function using right ventricular strain, right atrial reservoir strain and degree of tricuspid regurgitation provides accurate prognostic information in prevalent PAH patients.

The Right Ventricle in Pulmonary Hypertension

The right ventricle plays a pivotal role in patients with pulmonary hypertension (PH). Its adaptation to pressure overload determines a patient's functional status as well as survival. In a healthy situation, the right ventricle is part of a low pressure, high compliance system. It is built to accommodate changes in preload, but not very well suited for dealing with pressure overload. In PH, right ventricular (RV) contractility must increase to maintain cardiac output. In other words, the balance between the degree of RV contractility and afterload determines stroke volume. Hypertrophy is one of the major hallmarks of RV adaptation, but it may cause stiffening of the ventricle in addition to intrinsic changes to the RV myocardium. Ventricular filling becomes more difficult for which the right atrium tries to compensate through increased stroke work. Interaction of RV diastolic stiffness and right atrial (RA) function determines RV filling, but also causes vena cava backflow. Assessment of RV and RA function is critical in the evaluation of patient status. In recent guidelines, this is acknowledged by incorporating additional RV parameters in the risk stratification in PH. Several conventional parameters of RV and RA function have been part of risk stratification for many years. Understanding the pathophysiology of RV failure and the interactions with the pulmonary circulation and right atrium requires consideration of the unique RV anatomy. This review will therefore describe normal RV structure and function and changes that occur during adaptation to increased afterload. Consequences of a failing right ventricle and its implications for RA function will be discussed. Subsequently, we will describe RV and RA assessment in clinical practice.

Right ventricular assessment in pulmonary hypertension

PURPOSE OF REVIEW

The purpose of this review is to provide an overview of assessment of right ventricular function in the context of pulmonary hypertension and pulmonary arterial hypertension (PAH). We will review unique features of right ventricular anatomy, delineation of cause of pulmonary hypertension through careful right ventricular assessment, echocardiographic and hemodynamic evaluation, and the importance of this assessment in prognosis.

RECENT FINDINGS

The importance of performance in prognosis and risk assessment in patients with pulmonary hypertension has been continually emphasized in ongoing research. Representative parameters of right ventricular function have been shown to be predictive of prognosis in patients with pulmonary hypertension. Further, the importance of serial right ventricular assessment in risk assessment and prognosis has remained an emerging theme.

SUMMARY

Careful evaluation of right ventricular function is paramount in assessing the cause of pulmonary hypertension and severity of disease. Further, it has prognostic significance, as many representative parameters of right ventricular function have been linked with mortality. In our opinion, right ventricular function should be assessed serially throughout the course of treatment in pulmonary hypertension, and baseline parameters in addition to dynamic changes should be incorporated into risk assessment. Achieving normal or near-normal right ventricular performance may serve as a principal goal in the treatment of pulmonary hypertension.

Pathophysiology of the right ventricle in health and disease: an update

The contribution of the right ventricle (RV) to cardiac output is negligible in normal resting conditions when pressures in the pulmonary circulation are low. However, the RV becomes relevant in healthy subjects during exercise and definitely so in patients with increased pulmonary artery pressures both at rest and during exercise. The adaptation of RV function to loading rests basically on an increased contractility. This is assessed by RV end-systolic elastance (Ees) to match afterload assessed by arterial elastance (Ea). The system has reserve as the Ees/Ea ratio or its imaging surrogate ejection fraction has to decrease by more than half, before the RV undergoes an increase in dimensions with eventual increase in filling pressures and systemic congestion. RV-arterial uncoupling is accompanied by an increase in diastolic elastance. Measurements of RV systolic function but also of diastolic function predict outcome in any cause pulmonary hypertension and heart failure with or without preserved left ventricular ejection fraction. Pathobiological changes in the overloaded RV include a combination of myocardial fibre hypertrophy, fibrosis and capillary rarefaction, a titin phosphorylation-related displacement of myofibril tension-length relationships to higher pressures, a metabolic shift from mitochondrial free fatty acid oxidation to cytoplasmic glycolysis, toxic lipid accumulation, and activation of apoptotic and inflammatory signalling pathways. Treatment of RV failure rests on the relief of excessive loading.

Lung Imaging in COPD Part 1: Clinical Usefulness

COPD is a condition characterized by chronic airflow obstruction resulting from chronic bronchitis, emphysema, or both. The clinical picture is usually progressive with respiratory symptoms such as exertional dyspnea and chronic cough. For many years, spirometry was used to establish a diagnosis of COPD. Recent advancements in imaging techniques allow quantitative and qualitative analysis of the lung parenchyma as well as related airways and vascular and extrapulmonary manifestations of COPD. These imaging methods may allow prognostication of disease and shed light on the efficacy of pharmacologic and nonpharmacologic interventions. This is the first of a two-part series of articles on the usefulness of imaging methods in COPD, and it highlights useful information that clinicians can obtain from these imaging studies to make more accurate diagnosis and therapeutic decisions.

Multimodality Imaging of Right Heart Function: JACC Scientific Statement

Right ventricular (RV) size and function assessed by multimodality imaging are associated with outcomes in a variety of cardiovascular diseases. Understanding RV anatomy and physiology is essential in appreciating the strengths and weaknesses of current imaging methods and gives these measurements greater context. The adaptation of the right ventricle to different types and severity of stress, particularly over time, is specific to the cardiovascular disease process. Multimodality imaging parameters, which determine outcomes, reflect the ability to image the initial and longitudinal RV response to stress. This paper will review the standard and novel imaging methods for assessing RV function and the impact of these parameters on outcomes in specific disease states.

Derivation of a Risk Score (REVEAL-ECHO) Based on Echocardiographic Parameters of Patients With Pulmonary Arterial Hypertension

BACKGROUND

Multiparametric risk assessment tools determine mortality risk in patients with pulmonary arterial hypertension (PAH) by combining invasive and noninvasive variables so management strategies can be tailored to individuals.

RESEARCH QUESTION

Can a risk score based on common echocardiographic parameters risk-stratify patients with PAH?

STUDY DESIGN AND METHODS

A Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL) echocardiographic risk score (REVEAL-ECHO) was derived using retrospective echocardiographic data from 2,400 adult patients with PAH enrolled in the REVEAL registry database. A stepwise Cox regression model identified echocardiographic parameters significantly predictive of survival. Values were assigned to each selected parameter based on survival at 12 months' follow-up (Kaplan-Meier estimates). The REVEAL-ECHO risk score was the sum of individual values. Patients were categorized as having low, intermediate, or high risk based on Kaplan-Meier-predicted 12-month survival.

RESULTS

The risk score included four echocardiographic parameters-right ventricular (RV) chamber enlargement, reduced RV systolic function, tricuspid regurgitation severity, and pericardial effusion-and accounted for PAH etiology. Higher REVEAL-ECHO risk scores signaled lower probability of 12-month survival. Statistically significant separation of mortality risk was observed among the risk strata: intermediate vs low (hazard ratio [HR], 1.43; 95% CI, 1.17-1.75; P = .0004) and high vs low (HR, 2.60; 95% CI, 2.19-3.10; P < .0001). Augmentation of the REVEAL Lite 2 risk calculator with REVEAL-ECHO risk scores achieved separation of REVEAL Lite 2 into four risk groups and identified a subgroup of patients with a low REVEAL Lite 2 risk score who were at higher risk (intermediate-low risk) and a subgroup of patients with an intermediate REVEAL Lite 2 risk score who also were at higher risk (intermediate-high risk).

INTERPRETATION

A REVEAL-ECHO risk score, derived using four echocardiographic parameters, may discriminate risk further when used as an adjunct to current risk assessment scores. Further validation is required.

The heart of the matter: Right heart imaging indicators for treatment escalation in pulmonary arterial hypertension

Right heart (RH) structure and function are major determinants of symptoms and prognosis in pulmonary arterial hypertension (PAH). RH imaging provides detailed information, but evidence and guidelines on the use of RH imaging in treatment decisions are limited. We conducted a Delphi study to gather expert opinion on the role of RH imaging in decision-making for treatment escalation in PAH. A panel of 17 physicians with expertise in PAH and RH imaging used three surveys in a modified Delphi process to reach consensus on the role of RH imaging in PAH. Survey 1 used open-ended questions to gather information. Survey 2 contained Likert scale and other questions intended to identify consensus on topics identified in Survey 1. Survey 3 contained Likert scale questions derived from Survey 2 and summary information on the results of Survey 2. The Delphi panel reached consensus that RH imaging is likely to improve the current risk stratification algorithms and help differentiate risk levels in patients at intermediate risk. Tricuspid annular plane systolic excursion, right ventricular fractional area change, right atrial area, tricuspid regurgitation, inferior venae cavae diameter, and pericardial effusion should be part of routine echocardiography in PAH. Cardiac magnetic resonance imaging is valuable but limited by cost and access. A pattern of abnormal RH imaging results should prompt consideration of hemodynamic evaluation and possible treatment escalation. RH imaging is an important tool for decisions about treatment escalation in PAH, but systematically collected evidence is needed to clarify its role.

Improved Survival for Patients with Systemic Sclerosis-associated Pulmonary Arterial Hypertension: The Johns Hopkins Registry

Rationale: To date, it remains unclear whether recent changes in the management of patients with systemic sclerosis-associated pulmonary hypertension (SSc-PH) have improved survival. Objectives: To describe a cohort of patients with SSc-PH and compare their characteristics and survival between the last two decades. Methods: Patients with SSc-PH prospectively enrolled in the Johns Hopkins Pulmonary Hypertension Center Registry were grouped into two cohorts based on the date of diagnostic right heart catheterization: cohort A included patients whose disease was diagnosed between 1999 and 2010, and cohort B included those whose disease was diagnosed between 2010 and 2021. Patients' characteristics were compared between the two cohorts. Measurements and Main Results: Of 504 patients with SSc-PH distributed almost equally between the two cohorts, 308 (61%) had World Symposium on Pulmonary Hypertension group 1, 43 (9%) had group 2, and 151 (30%) had group 3 disease. Patients with group 1 disease in cohort B had significantly better clinical and hemodynamic characteristics at diagnosis, were more likely to receive upfront combination pulmonary arterial hypertension therapy, and had a nearly 4-year increase in median transplant-free survival in univariable analysis than those in cohort A (P < 0.01). Improved transplant-free survival was still observed after adjusting for patients' baseline characteristics. In contrast, for group 2 or 3 patients with SSc-PH, there were no differences in baseline clinical, hemodynamic, or survival characteristics between the two cohorts. Conclusions: This is the largest single-center study that compares clinical characteristics of patients with SSc-PH between the last two decades. Transplant-free survival has improved significantly for those with group 1 disease over the last decade, possibly secondary to earlier detection and better therapeutic management. Conversely, those with group 2 or 3 disease continue to have dismal prognosis.

Imaging the right atrium in pulmonary hypertension: A systematic review and meta-analysis

BACKGROUND

Right atrial (RA) imaging has emerged as a promising tool for the evaluation of patients with pulmonary hypertension (PH), albeit without systematic validation.

METHODS

PubMed, Web of Science and the Cochrane library were searched for studies investigating the prognostic value of RA imaging assessment in patients with PH from 2000 to June 2021 (PROSPERO Identifier: CRD42020212850). An inverse variance-weighted meta-analysis of univariable hazard ratios (HRs) was performed using a random effects model.

RESULTS

Thirty-five studies were included (3,476 patients with PH; 74% female, 86% pulmonary arterial hypertension). Risk of bias was low/moderate (Quality of Prognosis Studies checklist). RA area (HR 1.06; 95% confidence interval [CI] 1.04-1.08), RA indexed area (HR 1.09; 95% CI 1.04-1.14), RA peak longitudinal strain (PLS; HR 0.94; 95% CI 0.91-0.97) and RA total emptying fraction (HR 0.96; 95% CI 0.94-0.98) were significantly associated with combined end-points including death, clinical worsening and/or lung transplantation; RA volume and volume index showed marginal significant associations. RA area (HR 1.06; 95% CI 1.04-1.07), RA indexed area (HR 1.12; 95% CI 1.07-1.17) and RA PLS (HR 0.98; 95% CI 0.97-0.99) showed significant associations with mortality; RA total emptying fraction showed a marginal association.

CONCLUSIONS

Imaging-based RA assessment qualifies as a relevant prognostic marker in PH. RA area reliably predicts composite end-points and mortality, which underscores its clinical utility. RA PLS emerged as a promising imaging measure, but is currently limited by the number of studies and different acquisition methods.

Risk stratification in adult and pediatric pulmonary arterial hypertension: A systematic review

Introduction

Currently, risk stratification is the cornerstone of determining treatment strategy for patients with pulmonary arterial hypertension (PAH). Since the 2015 European Society of Cardiology/European Respiratory Society (ESC/ERS) guidelines for the diagnosis and treatment of pulmonary hypertension recommended risk assessment, the number of studies reporting risk stratification has considerably increased. This systematic review aims to report and compare the variables and prognostic value of the various risk stratification models for outcome prediction in adult and pediatric PAH.

Methods

A systematic search with terms related to PAH, pediatric pulmonary hypertension, and risk stratification was performed through databases PubMed, EMBASE, and Web of Science up to June 8, 2022. Observational studies and clinical trials on risk stratification in adult and pediatric PAH were included, excluding case reports/series, guidelines, and reviews. Risk of bias was assessed using the Prediction model Risk Of Bias Assessment Tool. Data on the variables used in the models and the predictive strength of the models given by c-statistic were extracted from eligible studies.

Results

A total of 74 studies were eligible for inclusion, with this review focusing on model development (n = 21), model validation (n = 13), and model enhancement (n = 9). The variables used most often in current risk stratification models were the non-invasive WHO functional class, 6-minute walk distance and BNP/NT-proBNP, and the invasive mean right atrial pressure, cardiac index and mixed venous oxygen saturation. C-statistics of current risk stratification models range from 0.56 to 0.83 in adults and from 0.69 to 0.78 in children (only two studies available). Risk stratification models focusing solely on echocardiographic parameters or biomarkers have also been reported.

Conclusion

Studies reporting risk stratification in pediatric PAH are scarce. This systematic review provides an overview of current data on risk stratification models and its value for guiding treatment strategies in PAH.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022316885], identifier [CRD42022316885].

Evaluation of right ventricular myocardial strain in pulmonary arterial hypertension associated with atrial septal defect by cardiac magnetic resonance feature tracking

We aimed to research the role of right ventricular strain parameters (RVSP) quantified by cardiac magnetic resonance feature tracking (CMR-FT) in the early assessment of right ventricular (RV) function in patients with pulmonary arterial hypertension associated with atrial septal defect (PAH-ASD). From September 2017 to May 2021, we retrospectively enrolled 41 patients with PAH-ASD and 20 healthy controls. All subjects underwent CMR-FT, and right heart catheterization was conducted in patients with PAH-ASD. The relationship between RVSP and RV functional parameters was subjected to correlation analysis, and intragroup correlation coefficient (ICC) and Bland-Altman plots were used to assess the consistency. The subjects were divided into three groups: Group A (controls; n = 20), Group B (PAH-ASD, RVEF ≥ 45%; n = 14), and Group C (PAH-ASD, RVEF < 45%; n = 27). Compared with healthy controls, the RV global longitudinal strain (GLS) in Group B was significantly decreased (- 19.68 ± 2.72% vs. - 25.21 ± 3.6%, P < 0.05). In RVEF-preserved PAH-ASD patients (Group B), compared with patients with GLS ≤ - 20%, patients with GLS > - 20% also had significantly elevated right ventricular end-diastolic pressure (RVEDP) [8 (6.5-8.25) mmHg vs. 4.5 ± 1.64 mmHg, P < 0.05]. RV GLS had a moderate to strong correlation with RVEF, RVESVi, RVEDVi, RVEDP, and NT-proBNP (P < 0.05). ICC and Bland-Altman plots showed good intragroup and intergroup consistency in radial, circumferential and longitudinal strains of RV. In conclusion, it is feasible to quantify RV strain in patients with PAH-ASD by CMR-FT, and GLS is valuable for the early assessment of RV dysfunction in patients with PAH-ASD.

Risk Stratification of Patients with Pulmonary Arterial Hypertension: The Role of Echocardiography

Background: Given the morbidity and mortality associated with pulmonary arterial hypertension (PAH), risk stratification approaches that guide therapeutic management have been previously employed. However, most patients remain in the intermediate-risk category despite initial therapy. Herein, we sought to determine whether echocardiographic parameters could improve the risk stratification of intermediate-risk patients. Methods: Prevalent PAH patients previously enrolled in observational studies at 3 pulmonary hypertension centers were included in this study. A validated PAH risk stratification approach was used to stratify patients into low-, intermediate-, and high-risk groups. Right ventricular echocardiographic parameters were used to further stratify intermediate-risk patients into intermediate-low- and intermediate-high-risk groups based on transplant-free survival. Results: From a total of 146 patients included in our study, 38 patients died over a median follow-up of 2.5 years. Patients with intermediate-/high-risk had worse echocardiographic parameters. Tricuspid annular plane systolic excursion (TAPSE) and the degree of tricuspid regurgitation (TR) were highly associated with survival (p < 0.01, p = 0.04, respectively) and were subsequently used to further stratify intermediate-risk patients. Among intermediate-risk patients, survival was worse for patients with TAPSE < 19 mm compared to those with TAPSE ≥ 19 mm (estimated one-year survival 74% vs. 96%, p < 0.01) and for patients with moderate/severe TR compared to those with no/trace/mild TR (estimated one-year survival 70% vs. 93%, p < 0.01). Furthermore, among intermediate-risk patients, those with both TAPSE < 19 mm and moderate/severe TR had an estimated one-year survival (56%) similar to that of high-risk patients (56%), and those with both TAPSE ≥ 19 mm and no/trace/mild TR had an estimated one-year survival (97%) similar to that of low-risk patients (95%). Conclusions: Echocardiography, a routinely performed, non-invasive imaging modality, plays a pivotal role in discriminating distinct survival phenotypes among prevalent intermediate-risk PAH patients using TAPSE and degree of TR. This can potentially help guide subsequent therapy.

Telehealth: A winning weapon to face the COVID-19 outbreak for patients with pulmonary arterial hypertension

Background

COVID-19 pandemic severely affected national health systems, altering the modality and the type of care of patients with acute and chronic diseases. To minimize the risk of exposure to SARS-CoV2 for patients and health professionals, face-to-face visits were cancelled or postponed and the use of telemedicine was strongly encouraged. This reorganization involved especially patients with rare diseases needing periodic comprehensive assessment, such as pulmonary arterial hypertension (PAH).

Main body

The paper reports a proposal of strategy adopted for patients followed at our PAH center in Rome, where patients management was diversified based on clinical risk according to the European Society of Cardiology/European Respiratory Society PH guidelines-derived score and the REVEAL 2.0 score. A close monitoring and support of these patients were made possible by policy changes reducing barriers to telehealth access and promoting the use of telemedicine. Synchronous/asynchronous modalities and remote monitoring were used to collect and transfer medical data in order to guide physicians in therapeutic-decision making. Conversely, the use of implantable monitors providing hemodynamic information and echocardiography-mobile devices wirelessly connecting was limited by the poor experience existing in this setting. Large surveys and clinical trials are welcome to test the potential benefit of the optimal balance between traditional PAH management and telemedicine opportunities.

Conclusion

Italy was found unprepared to manage the dramatic effects caused by COVID-19 on healthcare systems. In this emergency situation telemedicine represented a promising tool especially in rare diseases as PAH, but was limited by its scattered availability and legal and ethical issues. Cohesive partnership of health care providers with regional public health officials is needed to prioritize PAH patients for telemedicine by dedicated tools.

The added value of right ventricular function normalized for afterload to improve risk stratification of patients with pulmonary arterial hypertension

Background

Risk stratification is central to the management of pulmonary arterial hypertension (PAH). For this purpose, multiparametric tools have been developed, including the ESC/ERS risk score and its simplified versions derived from large database analysis such as the COMPERA and the French Pulmonary Hypertension Network (FPHN) registries. However, the distinction between high and intermediate-risk profiles may be difficult as the latter lacks granularity. In addition, neither COMPERA or FPHN strategies included imaging-derived markers. We thus aimed at investigating whether surrogate echocardiographic markers of right ventricular (RV) to pulmonary artery (PA) coupling could improve risk stratification in patients at intermediate-risk.

Material and methods

A single-center retrospective analysis including 102 patients with a diagnosis of PAH was performed. COMPERA and FPHN strategies were applied to stratify clinical risk. The univariate linear regression was used to test the influence of the echo-derived parameters qualifying the right heart (right ventricle basal diameter, right atrial area, and pressure, tricuspid regurgitation velocity, tricuspid annular plane systolic excursion -TAPSE-). Among these, the TAPSE and tricuspid regurgitation velocity ratio (TAPSE/TRV) as well as the TAPSE and systolic pulmonary artery pressure ratio (TAPSE/sPAP) were considered as surrogate of RV-PA coupling.

Results

TAPSE/TRV and TAPSE/sPAP resulted the more powerful markers of prognosis. Once added to COMPERA, TAPSE/TRV or TAPSE/sPAP significantly dichotomized intermediate-risk group in intermediate-to-low-risk (TAPSE/TRV≥3.74 mm∙nm/s)^-1 or TAPSE/sPAP≥0.24 mm/mmHg) and in intermediate-to-high-risk subgroups (TAPSE/TRV<3.74 mm∙(m/s)^-1 or TAPSE/sPAP<0.24 mm/mmHg). In the same way, TAPSE/TRV or TAPSE/sPAP was able to select patients at lower risk among those with 2, 1, and 0 low-risk criteria of both invasive and non-invasive FPHN registries.

Conclusions

Our results suggest that adopting functional-hemodynamic echo-derived parameters may provide a more accurate risk stratification in patients with PAH. In particular, TAPSE/TRV or TAPSE/sPAP improved risk stratification in patients at intermediate-risk, that otherwise would have remained less characterized.

The Right Heart Network and Risk Stratification in Pulmonary Arterial Hypertension

BACKGROUND

Prognosis in pulmonary arterial hypertension (PAH) is closely related to indexes of right ventricular function. A better understanding of their relationship may provide important implications for risk stratification in PAH.

RESEARCH QUESTION

Can clinical network graphs inform risk stratification in PAH?

STUDY DESIGN AND METHODS

The study cohort consisted of 231 patients with PAH followed up for a median of 7.1 years. An undirected, correlation network was used to visualize the relationship between clinical features in PAH. This network was enriched for right heart parameters and included N-terminal pro-hormone B-type natriuretic peptide (NT-proBNP), comprehensive echocardiographic parameters, and hemodynamics, as well as 6-min walk distance (6MWD), vital signs, laboratory data, and diffusing capacity for carbon monoxide (Dlco). Connectivity was assessed by using eigenvector and betweenness centrality to reflect global and regional connectivity, respectively. Cox proportional hazards regression was used to model event-free survival for the combined end point of death or lung transplantation.

RESULTS

A network of closely intertwined features centered around NT-proBNP with 6MWD emerging as a secondary hub were identified. Less connected nodes included Dlco, systolic BP, albumin, and sodium. Over the follow-up period, death or transplantation occurred in 92 patients (39.8%). A strong prognostic model was achieved with a Harrell's C-index of 0.81 (0.77-0.85) when combining central right heart features (NT-proBNP and right ventricular end-systolic remodeling index) with 6MWD and less connected nodes (Dlco, systolic BP, albumin, sodium, sex, connective tissue disease etiology, and prostanoid therapy). When added to the baseline risk model, serial change in NT-proBNP significantly improved outcome prediction at 5 years (increase in C-statistic of 0.071 ± 0.024; P = .003).

INTERPRETATION

NT-proBNP emerged as a central hub in the intertwined PAH network. Connectivity analysis provides explainability for feature selection and combination in outcome models.

Imaging and Risk Stratification in Pulmonary Arterial Hypertension: Time to Include Right Ventricular Assessment

Background

Current European Society of Cardiology and European Respiratory Society guidelines recommend regular risk stratification with an aim of treating patients with pulmonary arterial hypertension (PAH) to improve or maintain low-risk status (<5% 1-year mortality).

Methods

Consecutive patients with PAH who underwent cardiac magnetic resonance imaging (cMRI) were identified from the Assessing the Spectrum of Pulmonary hypertension Identified at a Referral centre (ASPIRE) registry. Kaplan-Meier survival curves, locally weighted scatterplot smoothing regression and multi-variable logistic regression analysis were performed.

Results

In 311 consecutive, treatment-naïve patients with PAH undergoing cMRI including 121 undergoing follow-up cMRI, measures of right ventricular (RV) function including right ventricular ejection fraction (RVEF) and RV end systolic volume and right atrial (RA) area had prognostic value. However, only RV metrics were able to identify a low-risk status. Age (p < 0.01) and RVEF (p < 0.01) but not RA area were independent predictors of 1-year mortality.

Conclusion

This study highlights the need for guidelines to include measures of RV function rather than RA area alone to aid the risk stratification of patients with PAH.

Assessment of right ventricle in pulmonary arterial hypertension with three-dimensional echocardiography and cardiovascular magnetic resonance

AIM

To correlate 3-D Echo and CMR RV parameters and to verify whether they are similarly related to the clinical conditions of patients with pulmonary arterial hypertension (PAH), a disease in which the RV plays a crucial prognostic role.

METHODS

We enrolled 34 consecutive PAH patients followed by our PAH clinics. All patients underwent a 3-D Echo and CMR assessment of RV volumes and functions in the same day. The presence or absence of correlation between major findings was investigated; functional RV parameters were also analyzed in relation to 6-min walking test (6MWT) results and BNP/Nt-proBNP plasma levels. Twenty-four subjects served as controls.

RESULTS

Good agreement was found between 3-D Echo and CMR measures of RV volumes [RV-end-diastolic volume (r = 0.72, P < 0.0001), RV-end-systolic volume (ESV) (r = 0.80, P < 0.0001)] and function [RV-EF (r = 0.73, P < 0.0001), RV-ESV/SV (r = 0.83, P = 0.001)] for all the subjects of the study. These correlations were stronger in PAH patients than in control subjects. Importantly, 3-D Echo and CMR RV-EF and RV to pulmonary arterial coupling (RV-ESV/SV) similarly correlated with BNP/Nt-proBNP levels and with functional capacity measured at 6MWT in the PAH patients group.

CONCLUSIONS

3-D Echo demonstrated a significant agreement with CMR in the assessment of RV volume and function in PAH patients. Both techniques showed a similar correlation with clinical and prognostic parameters. The use of 3-D Echo should be amply boosted in the real-world clinical evaluation of PAH patients.

Pulmonary Arterial Hypertension in Patients Infected with the Human Immunodeficiency Virus

It is important to recognize and treat human immunodeficiency virus-associated pulmonary arterial hypertension (HIV-PAH) because of the associated morbidity and mortality. With the introduction of antiretroviral therapies (ART), improved survival has changed the focus of treatment management from immunodeficiency-related opportunistic infections to chronic cardiovascular complications, including HIV-PAH. The 2018 6th World Symposium of Pulmonary Hypertension recommended a revised definition of PAH that might result in a greater number of patients with HIV-PAH; however, the implication of this change is not yet clear. Here, we review the current literature on the diagnosis, management, and outcomes of patients with HIV-PAH.

Non-Invasive Risk Prediction Based on Right Ventricular Function in Patients with Pulmonary Arterial Hypertension

BACKGROUND

Right ventricular dysfunction is a major determinant of outcome in pulmonary arterial hypertension (PAH). We aimed to identify echocardiographic right heart parameters associated with adverse outcome and to develop a non-invasive, echocardiography-based risk score for PAH patients.

METHODS AND RESULTS

In 254 PAH patients we analyzed functional status, laboratory results, and echocardiographic parameters. We included these parameters to estimate all-cause death or lung transplantation using Cox regression models. The analyses included a conventional model using guideline-recommended variables and an extended echocardiographic model. Based on the final model a 12-point risk score was derived, indicating the association with the primary outcome within five years. During a median follow-up time of 4.2 years 74 patients died or underwent lung transplantation. The conventional model resulted in a C-Index of 0.539, whereas the extended echocardiographic model improved the discrimination (C-index 0.639, p-value 0.017). Ultimately, the newly developed risk score included WHO functional class, 6-min walking distance, N-terminal brain natriuretic peptide concentrations, pericardial effusion, right atrial area, tricuspid annular plane systolic excursion, and fractional area change.

CONCLUSION

Integrating right heart function assessed by echocardiography improves prediction of death or lung transplantation in PAH patients. Independent validation of this finding is warranted.

Echocardiography in Pulmonary Arterial Hypertension: Is It Time to Reconsider Its Prognostic Utility?

Pulmonary arterial hypertension (PAH) is characterized by an insult in the pulmonary vasculature, with subsequent right ventricular (RV) adaptation to the increased afterload that ultimately leads to RV failure. The awareness of the importance of RV function in PAH has increased considerably because right heart failure is the predominant cause of death in PAH patients. Given its wide availability and reduced cost, echocardiography is of paramount importance in the evaluation of the right heart in PAH. Several echocardiographic parameters have been shown to have prognostic implications in PAH; however, the role of echocardiography in the risk assessment of the PAH patient is limited under the current guidelines. This review discusses the echocardiographic evaluation of the RV in PAH and during therapy, and its prognostic implications, as well as the potential significant role of repeated echocardiographic assessment in the follow-up of patients with PAH.

Echocardiography Monitoring of Pulmonary Hypertension after Pediatric Hematopoietic Stem Cell Transplantation: Pediatric Pulmonary Arterial Hypertension and Pulmonary Veno-Occlusive Disease after Hematopoietic Stem Cell Transplantation

Pulmonary hypertension (PH) is associated with high morbidity in children undergoing hematopoietic stem cell transplantation (HSCT). However, owing to the lack of sequential echocardiography, the nature of the condition is not fully understood. This study was conducted to investigate whether routine echocardiography performed after HSCT could detect patients with PH at an earlier stage and elucidate the role of intervention using tadalafil. The study population comprised 93 consecutive children age <18 years who underwent a total of 109 HSCTs. All patients underwent routine transthoracic echocardiography during HSCT. Four children (4%) with a median age of 4 years (range, 0.7 to 6 years) were found to have PH, and their median tricuspid regurgitation peak velocity (TRV) was 4.1 m/s (range, 3.5 to 4.2 m/s). PH was diagnosed at a median of 52 days (range, 21 to 118 days) after HSCT. Three of them were diagnosed with neuroblastoma, and 1 was diagnosed with infantile leukemia. One patient developed PH after autologous HSCT, and 3 received killer immunoglobulin-like receptor ligand-mismatched cord blood. Busulfan was used for conditioning in all patients, and the proportion of patients receiving this medication was significantly higher in the PH group compared with the non-PH group (100% versus 30%; P = .011). Three of the 4 patients had a durable response (TRV ≤2.8 m/s) at a median of 46 days (range, 14 to 79 days) after starting treatment with tadalafil. No patient experienced exacerbation of PH, and treatment was completed at median of 96 days (range, 46 to 212 days). Our data suggest that routine echocardiography monitoring after HSCT should be considered in children receiving busulfan, although the precise follow-up timing needs further study. In addition, safe and effective administration of tadalafil must be ensured by close monitoring.

Inflammatory Mechanisms in the Pathogenesis of Pulmonary Arterial Hypertension: Recent Advances

Inflammatory processes are increasingly recognized in the pathogenesis of the vascular remodeling that characterizes pulmonary arterial hypertension (PAH). Chronic inflammation may contribute to disease progression or serve as a biomarker of PAH severity. Furthermore, inflammatory pathways may represent possible therapeutic targets for novel PAH-specific drugs beyond the currently approved therapies targeting the endothelin, nitric oxide/cyclic GMP, and prostacyclin biological pathways. The main focus of this article is to provide recent advances in the understanding of the role of inflammatory pathways in the pathogenesis of PAH from preclinical studies and current clinical data supporting chronic inflammation in PAH patients and to discuss emerging therapeutic implications. © 2021 American Physiological Society. Compr Physiol 11:1805-1829, 2021.

A novel non-invasive and echocardiography-derived method for quantification of right ventricular pressure-volume loops

AIMS

We sought to assess the feasibility of constructing right ventricular (RV) pressure-volume (PV) loops solely by echocardiography.

METHODS AND RESULTS

We performed RV conductance and pressure wire (PW) catheterization with simultaneous echocardiography in 35 patients with pulmonary hypertension. To generate echocardiographic PV loops, a reference RV pressure curve was constructed using pooled PW data from the first 20 patients (initial cohort). Individual pressure curves were then generated by adjusting the reference curve according to RV isovolumic and ejection phase duration and estimated RV systolic pressure. The pressure curves were synchronized with echocardiographic volume curves. We validated the reference curve in the remaining 15 patients (validation cohort). Methods were compared with correlation and Bland-Altman analysis. In the initial cohort, echocardiographic and conductance-derived PV loop parameters were significantly correlated {rho = 0.8053 [end-systolic elastance (Ees)], 0.8261 [Ees/arterial elastance (Ea)], and 0.697 (stroke work); all P < 0.001}, with low bias [-0.016 mmHg/mL (Ees), 0.1225 (Ees/Ea), and -39.0 mmHg mL (stroke work)] and acceptable limits of agreement. Echocardiographic and PW-derived Ees were also tightly correlated, with low bias (-0.009 mmHg/mL) and small limits of agreement. Echocardiographic and conductance-derived Ees, Ees/Ea, and stroke work were also tightly correlated in the validation cohort (rho = 0.9014, 0.9812, and 0.9491, respectively; all P < 0.001), with low bias (0.0173 mmHg/mL, 0.0153, and 255.1 mmHg mL, respectively) and acceptable limits.

CONCLUSION

The novel echocardiographic method is an acceptable alternative to invasively measured PV loops to assess contractility, RV-arterial coupling, and RV myocardial work. Further validation is warranted.

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.

Galectin-3 Plasma Levels Are Associated with Risk Profiles in Pulmonary Arterial Hypertension

Galectin-3 is a circulating biomarker of fibrosis whose prognostic role in pulmonary arterial hypertension (PAH) has not been fully explored. We undertook a pilot study to evaluate the relationship between galectin-3 plasma levels and validated risk scores in PAH. The study included 70 PAH patients admitted to a single referral center from June 2016 to June 2018. Patients were stratified according to the REVEAL 2.0 risk score, according to the parameters suggested by the European Society of Cardiology and European Respiratory Society (ESC/ERS) Guidelines, and according to a focused echocardiographic assessment of right heart performance. The association between galectin-3 levels and risk profiles was evaluated by generalized linear regression model with adjustment for etiology. Galectin-3 plasma levels increased linearly in the three risk strata based on the REVEAL 2.0 score (from 16.0 ± 5.7 in low-risk to 22.4 ± 6.3 in intermediate-risk and in 26.9 ± 7.7 ng/mL in high-risk patients (p for trend < 0.001). Galectin-3 levels were significantly lower in low-risk patients defined according to the prognostic parameters of ESC/ERS Guidelines (delta between low-risk and intermediate/high-risk = -9.3, 95% CI -12.8 to -5.8, p < 0.001, p < 0.001). Additionally, galectin-3 levels were lower in the low-risk profile defined on the basis of the echocardiographic evaluation of right heart performance (delta between low-risk and intermediate-/high-risk = -6.3, 95% CI -9.9 to -2.7, p = 0.001). Galectin-3 plasma levels are directly associated with several risk profiles in PAH patients. The prognostic role of this biomarker in PAH is worthwhile to be explored in larger prospective studies.