Prognostic Value of Follow-Up Hemodynamic Variables After Initial Management in Pulmonary Arterial Hypertension

Intravascular Ultrasound Pulmonary Artery Denervation to Treat Pulmonary Arterial Hypertension (TROPHY1): Multicenter, Early Feasibility Study

OBJECTIVES

The aim of this study was to investigate whether therapeutic intravascular ultrasound pulmonary artery denervation (PDN) is safe and reduces pulmonary vascular resistance (PVR) in patients with pulmonary arterial hypertension (PAH) on a minimum of dual oral therapy.

BACKGROUND

Early studies have suggested that PDN can reduce PVR in patients with PAH.

METHODS

TROPHY1 (Treatment of Pulmonary Hypertension 1) was a multicenter, international, open-label trial undertaken at 8 specialist centers. Patients 18 to 75 years of age with PAH were eligible if taking dual oral or triple nonparenteral therapy and not responsive to acute vasodilator testing. Eligible patients underwent PDN (TIVUS System). The primary safety endpoint was procedure-related adverse events at 30 days. Secondary endpoints included procedure-related adverse events, disease worsening and death to 12 months, and efficacy endpoints that included change in pulmonary hemodynamic status, 6-min walk distance, and quality of life from baseline to 4 or 6 months. Patients were to remain on disease-specific medication for the duration of the study.

RESULTS

Twenty-three patients underwent PDN, with no procedure-related serious adverse events reported. The reduction in PVR at 4- or 6-month follow-up was 94 ± 151 dyn·s·cm-5 (p = 0.001) or 17.8%, which was associated with a 42 ± 63 m (p = 0.02) increase in 6-min walk distance and a 671 ± 1,555 step (p = 0.04) increase in daily activity.

CONCLUSIONS

In this multicenter early feasibility study, PDN with an intravascular ultrasound catheter was performed without procedure-related adverse events and was associated with a reduction in PVR and increases in 6-min walk distance and daily activity in patients with PAH on background dual or triple therapy.

Effect of Aldosterone on Senescence and Proliferation Inhibition of Endothelial Progenitor Cells Induced by Sirtuin 1 (SIRT1) in Pulmonary Arterial Hypertension

Background

Pulmonary arterial hypertension (PAH) is characterized by a progressive increase in pulmonary circulatory resistance. Pulmonary vascular endothelial dysfunction is one of the main causes of primary PAH. Endothelial progenitor cells (EPCs) can proliferate and differentiate into vascular endothelial cells and play an important role in maintaining normal endothelial function. Mineralocorticoid receptor inhibitor has been reported to be used in the treatment of PAH. However, the role and the underlying mechanism of aldosterone (ALDO) in PAH remains unclear.

Material/Methods

Rats were divided to 4 groups (n=10 per group) and treated with 0.9% normal saline, monocrotaline (MCT), spironolactone (SP), or MCT combined with SP. After the rats were sacrificed with an overdose of pentobarbital sodium, hematoxylin and eosin staining was performed to observe the pulmonary artery pathology section. Sirtuin 1 (SIRT1), p53, and p21 protein expression was detect by western blot. Immunofluorescence staining was performed to verify EPCs. EPCs were treated with different concentrations of ALDO. MTT assay and senescence-associated β-galactosidase staining were used to measure cell viability and senescence.

Results

MCT increased the vascular arterial wall thickness and wall area, inhibited SIRT1 protein expression and increased p53 and p21 protein expression in the lung tissue of rats, while SP partially reversed this effect. In addition, ALDO inhibited EPCs viability and induced senescence. The expression of p53 and p21 proteins in the EPCs were upregulated and the senescence was accelerated when EPCs were transfected with SIRT1 siRNA.

Conclusions

ALDO promoted EPCs senescence and inhibited EPCs proliferation by downregulating SIRT1, which regulates the p53/p21 pathway, thus promoting PAH.

Echocardiography-Derived Stroke Volume Index Is Associated With Adverse In-Hospital Outcomes in Intermediate-Risk Acute Pulmonary Embolism: A Retrospective Cohort Study

BACKGROUND

There remains uncertainty in the optimal prognostication and management of patients with intermediate-risk pulmonary embolism (PE). Transthoracic echocardiography can identify right ventricular dysfunction to recognize intermediate-high-risk patients.

RESEARCH QUESTION

Is echocardiographic-derived stroke volume index (SVI) associated with death or cardiopulmonary decompensation in intermediate-risk patients with PE?

STUDY DESIGN AND METHODS

and Methods: We retrospectively evaluated echocardiographic-derived variables that included SVI in normotensive patients with acute PE who were admitted between January 2012 and March 2017. SVI was determined with the use of the Doppler velocity-time integral in the left or right ventricular outflow tract. The primary outcome was in-hospital PE-related death or cardiopulmonary decompensation. We used logistic regression to determine the association between SVI and outcomes and receiver operating characteristic analysis to compare the performance of SVI and other echocardiographic measures.

RESULTS

The primary outcome occurred in 26 of the 665 intermediate-risk patients (3.9%) with PE. Univariate logistic regression showed an OR of 1.37 (95% CI, 1.23-1.52; P < .001) per 1-mL/m² decrease in SVI for the primary outcome. Bivariate logistic regression showed that SVI was independent of age, sex, heart rate, tricuspid regurgitation velocity, tricuspid annular plane systolic excursion, troponin, and Bova score. SVI had the highest C-statistic of 0.88 (95% CI, 0.81-0.96) of all echocardiographic variables with a Youden's J-statistic that identifies an optimal cut-point of 20.0 mL/m², which corresponds to positive and negative likelihood ratios of 6.5 (95% CI, 5.0-8.6) and 0.2 (95% CI, 0.1-0.5) for the primary outcomes, respectively.

INTERPRETATION

Low SVI was associated with in-hospital death or cardiopulmonary decompensation in acute PE. SVI had excellent performance compared with other clinical and echocardiographic variables.

Haemodynamic phenotypes and survival in patients with systemic sclerosis: the impact of the new definition of pulmonary arterial hypertension

BACKGROUND

In this study, we investigated the impact of the new haemodynamic definition of pulmonary arterial hypertension (PAH) as proposed by the 6th PH World Symposium on phenotypes and survival in patients with systemic sclerosis (SSc).

METHODS

In SSc patients who were prospectively and consecutively screened for PAH including right heart catheterisation in Heidelberg or Zurich, haemodynamic and clinical variables have been reassessed according to the new PAH definition. Patients have been followed for 3.7±3.7 (median 3.4) years; Kaplan-Meier survival analysis was performed. Patients with significant lung or left heart disease were excluded from comparative analyses.

RESULTS

The final dataset included 284 SSc patients, 146 patients (49.2%) had mean pulmonary arterial pressure (mPAP) ≤20 mm Hg, 19.3% had mPAP 21-24 mm Hg and 29.4% had mPAP ≥25 mm Hg. In the group of mildly elevated mPAP, only four patients (1.4% of the whole SSc cohort) had pulmonary vascular resistance (PVR) values ≥3 Wood Units (WU) and could be reclassified as manifest SSc-APAH. Twenty-eight (9.8%) patients with mPAP of 21-24 mm Hg and PVR ≥2 WU already presented with early pulmonary vascular disease with decreased 6 min walking distance (6MWD) (p<0.001), TAPSE (p=0.004) and pulmonary arterial compliance (p<0.001). A PVR ≥2 WU was associated with reduced long-term survival (p=0.002). PVR and 6MWD were independent prognostic predictors in multivariate analysis.

CONCLUSION

The data of this study show that a PVR threshold ≥3 WU is too high to enable an early diagnosis of PAH. A PVR threshold ≥2 WU was already associated with pulmonary vascular disease, significantly reduced survival and would be more appropriate in SSc patients with mild PAH.

Heart Disease and Stroke Statistics-2020 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports on the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2020 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, metrics to assess and monitor healthy diets, an enhanced focus on social determinants of health, a focus on the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors, implementation strategies, and implications of the American Heart Association's 2020 Impact Goals.

RESULTS

Each of the 26 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, healthcare administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Clinical implications of idiopathic pulmonary arterial hypertension phenotypes defined by cluster analysis

BACKGROUND

>Despite advances in drug development, life expectancy in idiopathic pulmonary arterial hypertension (IPAH) remains unacceptable. Contemporary IPAH characterization is based on criteria that may not adequately capture disease heterogeneity and may be proposed as a possible explanation for why patient outcome is still unfavorable. The aim of this study was to apply cluster analysis to improve phenotyping of patients with IPAH and analyze long-term clinical outcome of derived clusters.

METHODS

Patients with IPAH from 2 referral centers (n = 252) were evaluated with clinical, hemodynamic, and echocardiographic assessment and cardiopulmonary exercise test. Patients were classified according to cluster analysis and followed for clinical worsening occurrence.

RESULTS

The cluster analysis identified 4 IPAH phenotypes. Cluster 1 was characterized by young patients, mild pulmonary hypertension (PH), mild right ventricular (RV) dilation and high oxygen (O₂) pulse; Cluster 2 by severe PH and RV dilation and high O₂ pulse; and Cluster 3 by male patients, severe PH and RV dilation, and low O₂ pulse. Cluster 4 patients were older and overweight, with mild PH and RV dilation and low O₂ pulse. After a mean follow-up of 995 ± 623 days, 123 (48.8%) patients had clinical worsening. Cluster 1 patients presented the best prognosis, whereas Cluster 3 had the highest rates of clinical worsening. Compared with Cluster 1, risk of clinical worsening ranged from 4.12 (confidence interval [CI] 1.43-11.92; p = 0.009) for Cluster 4 to 7.38 (CI 2.80-19.40) for Cluster 2 and 13.8 (CI 5.60-34.0; p = 0.0001) for Cluster 3.

CONCLUSIONS

Cluster analysis of clinical variables identified 4 distinct phenotypes of IPAH. Our findings underscore the high degree of disease heterogeneity that exists within patients with IPAH and the need for advanced clinical testing to define phenotypes to improve treatment strategy decision-making. CONDENSED ABSTRACT Idiopathic pulmonary arterial hypertension (IPAH) characterization is based on criteria that may not adequately capture disease heterogeneity. The aim of this study was to apply cluster analysis to improve phenotyping of IPAH. Patients with IPAH (n = 252) were evaluated with clinical, hemodynamic, and echocardiographic assessment and cardiopulmonary exercise test. Within the umbrella category of IPAH, it was the combination of mean pulmonary arterial pressure, right ventricular size, and oxygen pulse that further stratified patients into novel IPAH phenotypes that significantly associate with clinical worsening. These findings underscore the need for novel multidimensional IPAH phenotyping for improved patient care and trial quality.

Cardiac Catheterization versus Echocardiography for Monitoring Pulmonary Pressure: A Prospective Study in Patients with Connective Tissue Disease-Associated Pulmonary Arterial Hypertension

Standard echocardiography is important for pulmonary arterial hypertension (PAH) screening in patients with connective tissue disease (CTD), but PAH diagnosis and monitoring require cardiac catheterization. Herein, using cardiac catheterization as reference, we tested the hypothesis that follow-up echocardiography is adequate for clinical decision-making in these patients. We prospectively studied 69 consecutive patients with CTD-associated PAH. Invasive baseline pulmonary artery systolic pressure (PASP) was 60.19 ± 16.33 mmHg (mean ± SD) and pulmonary vascular resistance (PVR) was 6.44 ± 2.95WU. All patients underwent hemodynamic and echocardiographic follow-up after 9.47 ± 7.29 months; 27 patients had a third follow-up after 17.2 ± 7.4 months from baseline. We examined whether clinically meaningful hemodynamic deterioration of follow-up catheterization-derived PASP (i.e., > 10% increase) could be predicted by simultaneous echocardiography. Echocardiography predicted hemodynamic PASP deterioration with 59% sensitivity, 85% specificity, and 63/83% positive/negative predictive value, respectively. In multivariate analysis, successful echocardiographic prediction correlated only with higher PVR in previous catheterization (p = 0.05, OR = 1.235). Notably, in patients having baseline PVR > 5.45 WU, echocardiography had both sensitivity and positive predictive values of 73%, and both specificity and negative predictive value of 91% for detecting hemodynamic PASP deterioration. In selected patients with CTD-PAH echocardiography can predict PASP deterioration with high specificity and negative predictive value. Additional prospective studies are needed to confirm that better patient selection can increase the ability of standard echocardiography to replace repeat catheterization.

ERS International Congress, Madrid, 2019: highlights from the Respiratory Intensive Care Assembly

The Respiratory Intensive Care Assembly of the European Respiratory Society is delighted to present the highlights from the 2019 International Congress in Madrid, Spain. We have selected four sessions that discussed recent advances in a wide range of topics: from acute respiratory failure to cough augmentation in neuromuscular disorders and from extra-corporeal life support to difficult ventilator weaning. The subjects are summarised by early career members in close collaboration with the Assembly leadership. We aim to give the reader an update on the most important developments discussed at the conference. Each session is further summarised into a short list of take-home messages.

The Role of Noninvasive Endpoints in Predicting Long-Term Outcomes in Pulmonary Arterial Hypertension

Background

Until recently, many clinical trials in patients with pulmonary arterial hypertension (PAH) evaluated exercise capacity with 6-minute walk distance (6MWD) as the primary endpoint. Common secondary endpoints include PAH functional class (FC), which assesses symptoms, and either brain natriuretic peptide (BNP) or the inactive N-terminal cleavage product of its prohormone (NT-proBNP), which assesses cardiac function.

Objective

Examine the relationships among 6MWD, FC, and BNP/NT-proBNP measured at baseline or follow-up with long-term outcomes in PAH studies.

Methods

Relevant literature from January 1990 to April 2018 were obtained by searching PubMed, Embase, and Cochrane. Articles in English reporting on associations between 6MWD, FC, or BNP/NT-proBNP and outcomes in PAH were identified. Each endpoint was evaluated individually. Prespecified inclusion and exclusion criteria were applied at level 1 (titles/abstracts) and level 2 (full-text review).

Results

The database search yielded 836 unique records; 65 full-text articles were reviewed. Twenty-five studies were eligible for inclusion. Findings supported the importance of measuring PAH noninvasive endpoints in predicting long-term outcomes. Patients with shorter or decreased 6MWD, poor (III/IV) or declining FC (e.g., from II to III), or elevated or increasing BNP/NT-proBNP had a higher risk of death and costly events (e.g., hospitalization, lung transplant). FC also predicted health care resource utilization and costs. Collectively, these endpoints establish risk groups that predict likelihood of complications from PAH or death.

Conclusion

Assessment of 6MWD, FC, and BNP/NT-proBNP provides low-cost, efficient, and noninvasive means of predicting long-term health and economic outcomes in patients with PAH.

[Risk stratification methods and their significance in pulmonary arterial hypertension]

Despite significant advances in therapy, pulmonary arterial hypertension (PAH) remains a progressive disease with a poor prognosis. Immediately after establishing the diagnosis of PAH, urgent treatment with PAH-specific therapy is required. Due to the progressive nature of the disease, all patients should be closely monitored and their treatment regimen should be promptly changed according to clinical need. Risk stratification is an important method for informing the clinician and the patient about the prognosis of disease and the choice of therapy methods. The REVEAL scale and the ESC/ERS 2015 risk assessment table are important multifactorial tools for making decisions about the prescription and correction of PAH therapy, as well as for assessment of patients' response to therapy. Current guidelines for PAH indicate that the most important task of treatment of PAH is to achieve the low - risk status.

Sex-specific differences and survival in patients with idiopathic pulmonary arterial hypertension 2008-2016

Background

Women with idiopathic pulmonary arterial hypertension (IPAH) have been found to have a worse haemodynamic status at diagnosis, but better survival than men. Over the past decade, demographics have changed and new treatments have become available. The objective of this study was to investigate sex differences in an incident IPAH population diagnosed between 2008 and 2016.

Methods

Differences in clinical characteristics of patients included in the Swedish Pulmonary Arterial Hypertension Register (SPAHR) were analysed at the time of diagnosis. Survival by sex was investigated using Cox proportional hazard regression and Kaplan–Meier curves.

Results

The study included 271 patients diagnosed with IPAH, median age was 68 (1st–3rd quartiles 54–74) years and 56% were women. At diagnosis, women were younger, had lower pulmonary vascular resistance and fewer comorbidities and more often received a combination of PAH-targeted therapies than men. Men had worse survival rates than women (hazard ratio 1.49; CI 1.02–2.18; p=0.038), but this difference did not remain after adjustment for age (hazard ratio 1.30; CI 0.89–1.90; p=0.178).

Conclusions

Men with incident IPAH have worse crude survival than women. This is due to women being younger with a less pronounced comorbidity burden than men at the time of diagnosis.

Despite minor differences in baseline characteristics between men and women, survival among patients with incident IPAH diagnosed 2008–2016 does not appear to be related to sexhttp://bit.ly/2JFgXhd

Vena cava backflow and right ventricular stiffness in pulmonary arterial hypertension

Vena cava backflow is a well-recognised clinical hallmark of right ventricular failure in pulmonary arterial hypertension (PAH). Backflow may result from tricuspid regurgitation during right ventricular systole or from impaired right ventricular diastolic filling during atrial contraction. Our aim was to quantify the forward and backward flow in the vena cava and to establish the main cause in PAH.

In 62 PAH patients, cardiac magnetic resonance measurements provided volumetric flows (mL·s−1) in the superior and inferior vena cava; time integration of flow gave volume. The “backward fraction” was defined as the ratio of the backward and forward volumes in the vena cava, expressed as a percentage. Time of maximum vena cava backflow was expressed as a percentage of the cardiac cycle. Right ventricular volumes and aortic stroke volume were determined. Right heart catheterisation gave right ventricular and right atrial pressures. Right ventricular end-diastolic stiffness was determined with the single-beat method.

The median (interquartile range) backward fraction was 12% (3–24%) and it was >20% in 21 patients. Maximum backflow occurred at near 90% of the cardiac cycle, coinciding with atrial contraction. The backward fraction was associated with maximal right atrial pressure (Spearman's r=0.77), right ventricular end-diastolic stiffness (r=0.65) and right ventricular end-diastolic pressure (r=0.77), and was negatively associated with stroke volume (r= –0.61) (all p<0.001).

Significant backward flow in the vena cava was observed in a large group of PAH patients and occurred mostly during atrial contraction as a consequence of impaired right ventricular filling due to right ventricular diastolic stiffness. The backward flow due to tricuspid regurgitation was of significance in only a small minority of patients.

Monitoring Pulmonary Arterial Hypertension Using an Implantable Hemodynamic Sensor

BACKGROUND

Pulmonary arterial hypertension (PAH) is a chronic disease that ultimately progresses to right-sided heart failure (HF) and death. Close monitoring of pulmonary artery pressure (PAP) and right ventricular (RV) function allows clinicians to appropriately guide therapy. However, the burden of commonly used methods to assess RV hemodynamics, such as right heart catheterization, precludes frequent monitoring. The CardioMEMS HF System (Abbott) is an ambulatory implantable hemodynamic monitor, previously only used in patients with New York Heart Association (NYHA) class III HF. In this study, we evaluate the feasibility and early safety of monitoring patients with PAH and right-sided HF using the CardioMEMS HF System.

METHODS

The CardioMEMS HF sensors were implanted in 26 patients with PAH with NYHA class III or IV right-sided HF (51.3 ± 18.3 years of age, 92% women, 81% NYHA class III). PAH therapy was tracked using a minimum of weekly reviews of CardioMEMS HF daily hemodynamic measurements. Safety, functional response, and hemodynamic response were tracked up to 4 years with in-clinic follow-ups.

RESULTS

The CardioMEMS HF System was safely used to monitor PAH therapy, with no device-related serious adverse events observed and a single preimplant serious adverse event. Significant PAP reduction and cardiac output elevation were observed as early as 1 month postimplant using trends of CardioMEMS HF data, coupled with significant NYHA class and quality of life improvements within 1 year.

CONCLUSIONS

The CardioMEMS HF System provided useful information to monitor PAH therapy, and demonstrated short- and long-term safety. Larger clinical trials are needed before its widespread use to guide therapy in patients with severe PAH with right-sided HF.

The Use of Risk Assessment Tools and Prognostic Scores in Managing Patients with Pulmonary Arterial Hypertension

PURPOSE OF REVIEW

Pulmonary arterial hypertension (PAH) is a chronic, progressive, and incurable disease with significant morbidity and mortality. Despite increasingly available treatment options, PAH patients continue to experience disease progression and increased rates of hospitalizations due to right heart failure. Physician's ability to comprehensively assess PAH patients, determine prognosis, and monitor disease progression and response to treatment remains critical in optimizing outcomes.

RECENT FINDINGS

Risk assessment in PAH should include a range of clinical, hemodynamic, and exercise parameters, performed in a serial fashion over the course of treatment. Approaches to risk assessment in PAH patients include the use of risk variables, scores, and equations that stratify the impact of both modifiable (e.g., 6-min walk distance, functional class, brain natriuretic peptide), and non-modifiable (e.g., age, gender, PAH etiology) risk factors. Such tools allow physicians to better determine prognosis, allocate treatment resources, and enhance the consistency of treatment approaches across providers. Comprehensive and accurate risk prediction is essential to make individualized treatment decisions and optimizing outcomes in PAH.

Differences in pulmonary arterial flow hemodynamics between children and adults with pulmonary arterial hypertension as assessed by 4D-flow CMR studies

Despite different developmental and pathological processes affecting lung vascular remodeling in both patient populations, differences in 4D MRI findings between children and adults with PAH have not been studied. The purpose of this study was to compare flow hemodynamic state, including flow-mediated shear forces, between pediatric and adult patients with PAH matched by severity of pulmonary vascular resistance index (PVRi). Adults (n = 10) and children (n = 10) with PAH matched by pulmonary vascular resistance index (PVRi) and healthy adult (n = 10) and pediatric (n = 10) subjects underwent comprehensive 4D-flow MRI to assess peak systolic wall shear stress (WSS_max) measured in the main (MPA), right (RPA), and left pulmonary arteries (LPA), viscous energy loss (E_L) along the MPA-RPA and MPA-LPA tract, and qualitative analysis of secondary flow hemodynamics. WSS_max was decreased in all pulmonary vessels in children with PAH when compared with the same age group (all P < 0.05). Similarly, WSS_max was decreased in all pulmonary vessels in adult PAH patients when compared with healthy adult subjects (all P < 0.01). Average E_L was increased in adult patients with PAH when compared with the same age group along both MPA-RPA (P = 0.020) and MPA-LPA (P = 0.025) tracts. There were no differences in E_L indices between adults and pediatric patients. Children and adult patients with PAH have decreased shear hemodynamic forces. However, pathological flow hemodynamic formations appear to be more consistent in adult patients, whereas flow hemodynamic abnormalities appear to be more variable in children with PAH for comparable severity of PVRi.

NEW & NOTEWORTHY Both children and adult patients with PAH have decreased shear hemodynamic forces inside the pulmonary arteries associated with the degree of vessel dilation and stiffness. These differences also exist between healthy normotensive children and adults. However, pathological flow hemodynamic formations appear to more uniform in adult patients, whereas in children with PAH flow, hemodynamic abnormalities appear to be more variable. Pathological flow formations appear not to have a major effect on viscous energy loss associated with the flow conduction through proximal pulmonary arteries.

Survival in pulmonary hypertension due to chronic lung disease: Influence of low diffusion capacity of the lungs for carbon monoxide

BACKGROUND

Patients with pulmonary hypertension (PH) due to chronic lung disease (Group 3 PH) have poor long-term outcomes. However, predictors of survival in Group 3 PH are not well described.

METHODS

We performed a cohort study of Group 3 PH patients (n = 143; mean age 65 ± 12 years, 52% female) evaluated at the University of Minnesota. The Kaplan-Meier method and Cox regression analysis were used to assess survival and predictors of mortality, respectively. The clinical characteristics and survival were compared in patients categorized by PH severity based on the World Health Organization (WHO) classification and lung disease etiology.

RESULTS

After a median follow-up of 1.4 years, there were 69 (48%) deaths. The 1-, 3-, and 5-year survival rates were 79%, 48%, and 31%. Age, coronary artery disease, atrial fibrillation, Charlson comorbidity index, serum N-terminal pro‒brain natriuretic peptide (NT-proBNP), creatinine, diffusion capacity of carbon monoxide (DLCO), total lung capacity, left ventricular ejection fraction, right atrial and right ventricular enlargement on echocardiography, cardiac index, and pulmonary vascular resistance (PVR) were univariate predictors of survival. On multivariable analysis, DLCO was the only predictor of mortality (adjusted hazard ratio [HR] for every 10% decrease in predicted value: 1.31 [95% confidence interval 1.12 to 1.47]; p = 0.003). The 1-/5-year survival by tertiles of DLCO was 84%/56%, 82%/44%, and 63%/14% (p = 0.01), respectively. On receiver-operating characteristic curve analysis, DLCO <32% of predicted had the highest sensitivity and specificity for predicting survival. The 1- and 5-year survival in patients with a DLCO ≥32% predicted was 84% and 60% vs 68% and 13% in patients with a DLCO <32% predicted (adjusted HR: 2.5 [95% confidence interval 1.3 to 5.0]; p = 0.007). Lung volumes and DLCO were not related, but higher PVR was strongly associated with reduced DLCO. There was increased mortality in interstitial lung disease‒PH as compared with chronic obstructive pulmonary disease‒PH, but PH severity based on the WHO classification did not alter survival.

CONCLUSIONS

Low DLCO is a predictor of mortality and should be used to risk-stratify Group 3 PH patients.

Exercise cardiovascular magnetic resonance imaging allows differentiation of low-risk pulmonary arterial hypertension

BACKGROUND

Patients with pulmonary arterial hypertension (PAH) have a decreased ability to compensate for demands on increased cardiac output, such as during exercise. In this study we aimed to differentiate cardiac exercise responses in patients with PAH, stratified according to known measurements of disease severity.

METHODS

Right and left ventricular end-diastolic volume and end-systolic volume, stroke volume (SV), and cardiac output were measured in 20 patients with PAH and a lower risk of mortality with 6-month intervals using cardiovascular magnetic resonance (CMR) imaging during rest and during ergometer exercise (totaling 44 scans). Exercise measurements were compared with resting cardiac conditions and clinical assessment using mixed model statistics.

RESULTS

SV response during exercise was associated with disease severity. World Health Organization functional class (WHO FC) I and right ventricular end-diastolic volume (RVEDV) <221 ml were associated with increased SV during exercise (WHO FC I: 7% increase in SV; p < 0.001). In contrast, WHO FC II was associated with an 8% decrease in SV (p = 0.02), and SV response declined progressively with right ventricular dilation (7-ml decrease in SV per 100-ml increase in RVEDV; p < 0.001).

CONCLUSIONS

Assessment of right ventricular function with CMR during exercise stratifies patients currently perceived as having a low risk of mortality into different degrees of right ventricular inotropic reserve. Reduced SV during exercise is a plausible factor to increased risk of decompensation, possibly warranting targeted therapy intensification to restore right ventricular functional reserve.

Therapeutic potential of phosphodiesterase type 5 inhibitors in heart failure with preserved ejection fraction and combined post- and pre-capillary pulmonary hypertension

OBJECTIVE

Heart failure with preserved ejection fraction (HFpEF) is frequently associated with pulmonary hypertension (PH), which substantially impacts survival. Based on pulmonary vascular resistance (PVR) and the diastolic pressure gradient (DPG), current guidelines distinguish between isolated post-capillary PH (IpcPH) and combined post- and pre-capillary PH (CpcPH). However, the therapeutic consequences of this sub-classification remain entirely unclear. We specifically investigated the efficacy and safety of PDE5i in patients with HFpEF and CpcPH.

METHODS

In 40 hemodynamically precisely characterized patients with HFpEF and Cpc-PH who were treated with a PDE5i for at least 12 months, the therapeutic effect on 6-minute walk distance (6MWD), WHO functional class (FC), NTproBNP levels, right ventricular function, and hospitalization rates was evaluated.

RESULTS

Patients' mean age was 73 ± 9 years, and comorbidities were frequent (78% hypertension, 58% atrial fibrillation, 35% diabetes). Initially, 38 patients (95%) were in WHO-FC III and 2 patients (5%) in WHO-FC II. Prior to PDE5i initiation, mean PAPm was 46.2 ± 10.3 mmHg, PAWP 21.2 ± 4.7 mmHg, DPG 5.5 ± 7.2 mmHg, and PVR 6.2 ± 3.0 WU. After 12 months of PDE5i therapy, the 6MWD increased from initially 277 ± 17 to 340 ± 18 m (p < 0.001), and the proportion of patients in WHO-FC I/II increased from 5% to 37.5%. NTproBNP levels decreased by 33% (p = 0.004), and TAPSE improved from 16.8 ± 0.7 mm at baseline to 18.2 ± 0.6 mm (p = 0.01). The rate of HF-associated hospitalizations was substantially lower in the 12 months post PDE5i initiation compared to the prior 12 months. The DPG had no impact on the response to therapy. No deaths occurred, and typical side effects of PDE5i were observed.

CONCLUSION

These data indicate that at least a subset of precisely characterized patients with HFpEF and CpcPH who tolerate PDE5i may benefit from targeted therapy. A randomized study in this particular sub-population is warranted.

The added value of cardiopulmonary exercise testing in the follow-up of pulmonary arterial hypertension

BACKGROUND

The added value of cardiopulmonary exercise testing (CPET) in the follow-up of patients with stable pulmonary arterial hypertension (PAH) remains undefined.

METHODS

Idiopathic, heritable, and drug-induced PAH patients free from clinical worsening (CW) after 1 year of treatment were enrolled in derivation (n = 80) and validation (n = 80) cohorts at an interval of 6 years and followed for 3 years. Prognostic models were constructed and validated in low-risk patients in World Health Organization (WHO) Functional Class I or II with cardiac index (CI) ≥2.5 liters/min/m² and right atrial pressure (RAP) <8 mm Hg. Discrimination and calibration were assessed.

RESULTS

Forty-one derivation cohort patients had CW (51.2%) during 722 ± 349 days. Changes (∆) in WHO classification and CI and absolute value of RAP were independent predictors of CW. With addition of CPET variables, peak oxygen uptake (VO₂ peak) and ∆CI independently improved the power of the prognostic model. Receiver operating characteristic (ROC)-derived cut-off values for ∆CI and VO₂ peak were 0.40 liter/min/m² and 15.7 ml/kg/min (≥60% predicted value), respectively. Twenty-nine validation cohort patients had CW (36.2%) during 710 ± 282 days. Different combinations of cut-off values of VO₂ peak and ∆CI defined 4 groups. The event-free survival rates at 1, 2, and 3 years were 100%, 100%, and 100%, respectively, for the high ∆CI with high VO₂ peak combination; 100%, 88%, and 71% for low ∆CI/high VO₂ peak; 80%, 54%, and 40% for high ∆CI/low VO₂ peak; and 72%, 54%, and 33% for low ∆CI/low VO₂ peak.

CONCLUSIONS

The combinations of baseline VO₂ peak and change in CI during follow-up is important in prognostication of low-risk patients with idiopathic, heritable, and drug-induced PAH.

Right heart size and function significantly correlate in patients with pulmonary arterial hypertension - a cross-sectional study

BACKGROUND

The objective of this study was to assess, whether right atrial (RA) and ventricular (RV) size is related to RV pump function at rest and during exercise in patients with pulmonary arterial hypertension (PAH).

METHODS

We included 54 patients with invasively diagnosed PAH that had been stable on targeted medication. All patients underwent clinical assessments including right heart catheterization and echocardiography at rest and during exercise. RV output reserve was defined as increase of cardiac index (CI) from rest to peak exercise (∆CI_exercise). Patients were classified according to the median of RA and RV-area. RV pump function and further clinical parameters were compared between groups by student's t-test. Uni- and multivariate Pearson correlation analyses were performed.

RESULTS

Patients with larger RA and/or RV-areas (above a median of 16 and 20cm², respectively) showed significantly lower ∆CI_exercise, higher mean pulmonary arterial pressure, pulmonary vascular resistance at rest and NT-proBNP levels. Furthermore, patients with higher RV-areas presented with a significantly lower RV stroke volume and pulmonary arterial compliance at peak exercise than patients with smaller RV-size. RV area was identified as the only independent predictor of RV output reserve.

CONCLUSION

RV and RA areas represent valuable and easily accessible indicators of RV pump function at rest and during exercise. Cardiac output reserve should be considered as an important clinical parameter. Prospective studies are needed for further evaluation.

Pulmonary Arterial Hypertension

This article provides an overview of pulmonary arterial hypertension (PAH), beginning with the initial pathologic recognition of pulmonary hypertension more than 100 years ago and progressing to the current diagnostic categorization of PAH. It reviews the epidemiology, pathophysiology, genetics, and modern treatment of PAH. The article discusses several important recent studies that have highlighted the importance of new management strategies, including serial risk assessment and combination pharmacotherapy.

Haemodynamics and serial risk assessment in systemic sclerosis associated pulmonary arterial hypertension

The prognostic importance of follow-up haemodynamics and the validity of multidimensional risk assessment are not well established for systemic sclerosis (SSc)-associated pulmonary arterial hypertension (PAH).We assessed incident SSc-PAH patients to determine the association between clinical and haemodynamic variables at baseline and first follow-up right heart catheterisation (RHC) with transplant-free survival. RHC variables included cardiac index, stroke volume index (SVI), pulmonary arterial compliance and pulmonary vascular resistance. Risk assessment was performed according to the number of low-risk criteria: functional class I or II, 6-min walking distance (6MWD) >440 m, right atrial pressure <8 mmHg and cardiac index ≥2.5 L·min^-1·m^-2Transplant-free survival from diagnosis (n=513) was 87%, 55% and 35% at 1, 3 and 5 years, respectively. At baseline, 6MWD was the only independent predictor. A follow-up RHC was available for 353 patients (median interval 4.6 months, interquartile range 3.9-6.4 months). The 6MWD, functional class, cardiac index, SVI, pulmonary arterial compliance and pulmonary vascular resistance were independently associated with transplant-free survival at follow-up, with SVI performing better than other haemodynamic variables. 1-year outcomes were better with increasing number of low-risk criteria at baseline (area under the curve (AUC) 0.63, 95% CI 0.56-0.69) and at first follow-up (AUC 0.71, 95% CI 0.64-0.78).Follow-up haemodynamics and multidimensional risk assessment had greater prognostic significance than at baseline in SSc-PAH.

Risk stratification strategy and assessment of disease progression in patients with pulmonary arterial hypertension: Updated Recommendations from the Cologne Consensus Conference 2018

In the summer of 2016, delegates from the German Respiratory Society, the German Society of Cardiology and the German Society of Pediatric Cardiology met in Cologne, Germany, to define consensus-based practice recommendations for the management of patients with pulmonary arterial hypertension (PAH). These recommendations were built on the 2015 European Pulmonary Hypertension guidelines and included new evidence, where available, and were last updated in the spring of 2018. This article focusses on the proposed risk stratification and assessment of disease progression in patients with pulmonary arterial hypertension (PAH), covering 3 parts: In part 1, methods and markers that are recommended to assess severity and progression of PAH are discussed and commented. These updated comments incorporate most recent data as well as challenges arising from the variability of phenotypes of PAH patients with increasing cardiopulmonary comorbidities. In part 2, the proposed ESC/ERS risk stratification strategy is discussed, together with a review of the recent validation studies from different European registries. Finally, in part 3, the working group of the Cologne Consensus Conference provides recommendations on how risk assessment may be implemented in routine clinical practice and may serve clinical decision making.

Echocardiographic assessment of pulmonary hypertension: a guideline protocol from the British Society of Echocardiography

Pulmonary hypertension is defined as a mean arterial pressure of ≥25 mmHg as confirmed on right heart catheterisation. Traditionally, the pulmonary arterial systolic pressure has been estimated on echo by utilising the simplified Bernoulli equation from the peak tricuspid regurgitant velocity and adding this to an estimate of right atrial pressure. Previous studies have demonstrated a correlation between this estimate of pulmonary arterial systolic pressure and that obtained from invasive measurement across a cohort of patients. However, for an individual patient significant overestimation and underestimation can occur and the levels of agreement between the two is poor. Recent guidance has suggested that echocardiographic assessment of pulmonary hypertension should be limited to determining the probability of pulmonary hypertension being present rather than estimating the pulmonary artery pressure. In those patients in whom the presence of pulmonary hypertension requires confirmation, this should be done with right heart catheterisation when indicated. This guideline protocol from the British Society of Echocardiography aims to outline a practical approach to assessing the probability of pulmonary hypertension using echocardiography and should be used in conjunction with the previously published minimum dataset for a standard transthoracic echocardiogram.

Clinical and genetic associations with prostacyclin response in pulmonary arterial hypertension

Parenteral prostacyclin therapy is the most efficacious pharmacologic treatment for pulmonary arterial hypertension (PAH), but clinical response is variable. We sought to identify clinical, hemodynamic, and genetic associations with response to prostacyclin therapy. We performed a retrospective analysis of patients within a de-identified electronic health record and associated DNA biobank. Patients with PAH and a right heart catheterization (RHC) in the six months before initiation of a parenteral prostacyclin were included. Responders were defined a priori by attainment of World Health Organization (WHO) functional class (FC) 2 or better at the time of repeat RHC within two years. We performed exploratory analyses to identify genomic associations with prostacyclin response. Of 129 patients identified, 54 met our criteria for “responders.” These patients were younger, more likely to be male, and were less likely to have connective tissue disease-related PAH. At follow-up, responders had improved hemodynamics, 6-min walk distance, and long-term survival. Baseline PA oxygen saturation (hazard ratio [HR] 0.568 [0.34–0.95]) and follow-up FC (HR = 2.57 [1.22–5.43]) were associated with survival. Prostacyclin responders were enriched in alleles related to cell development and circulatory system development and pathways related to aldosterone metabolism, cAMP signaling, and vascular smooth muscle contraction (P < 0.001). Age at treatment initiation, WHO FC at short-term follow-up, and PA O₂% are associated with survival in patients with PAH exposed to parenteral prostacyclins. Exploratory genetic analysis yielded associations in biologically relevant pathways in the pathogenesis of PAH.

Berberine attenuates pulmonary arterial hypertension via protein phosphatase 2A signaling pathway both in vivo and in vitro

Excessive proliferation, migration, and antiapoptosis of pulmonary artery (PA) smooth muscle cells (PASMCs) underlies the development of pulmonary vascular remodeling. The innervation of the PA is predominantly sympathetic, and increased levels of circulating catecholamines have been detected in pulmonary arterial hypertension (PAH), suggesting that neurotransmitters released by sympathetic overactivation may play an essential role in PAH. However, the responsible mechanism remains unclear. Here, to investigate the effects of norepinephrine (NE) on PASMCs and the related mechanism, we used 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, the proliferating cell nuclear antigen and the cell counting kit-8 assay to evaluate the proliferation of PASMCs, Boyden chamber migration, and wound-healing assays to assess migration and western blot analysis to investigate protein expression. We demonstrated that the phosphorylation level of the protein phosphatase 2A (PP2A) catalytic subunit (Y307) was higher in PAH patients and PAH models than in controls, both in vivo and in vitro. In addition, NE induced the proliferation and migration of PASMCs, which was attenuated by berberine (BBR), a Chinese herbal medicine, and/or PP2A overexpression. PP2A inhibition worsened NE-induced PAH and could not be reversed by BBR. Thus, PP2A is critical in driving PAH, and BBR may alleviate PAH via PP2A signaling pathways, thereby offering a potential therapeutic option for PAH.

Association Between BMI and Obesity With Survival in Pulmonary Arterial Hypertension

BACKGROUND

An obesity paradox, wherein patients who are obese have lower mortality, has been described in cardiopulmonary diseases, including pulmonary arterial hypertension (PAH). Our objective was to determine whether obesity and BMI are associated with mortality in patients with PAH.

METHODS

We assessed incident patients with idiopathic, drug-induced, and heritable PAH from the French Pulmonary Hypertension Network registry. Cox regression and Kaplan-Meier analysis were used to assess the association between BMI and obesity with all-cause mortality.

RESULTS

Of 1,255 patients included, 30% were obese. A higher proportion of women (65.1% vs 53.4%, P < .01), drug-induced PAH (28.9% vs 9.2%, P < .01), systemic hypertension, diabetes, and hypothyroidism were present in the obese group. More obese patients were in New York Heart Association class III (66.4% vs 57.1%), fewer were class IV (11.8% vs 16.9%, P < .01), and 6-min walk distance was lower (276 ± 121 vs 324 ± 146, P < .01). Right atrial pressure, pulmonary wedge pressure, and cardiac index were higher, whereas pulmonary vascular resistance was lower in patients who were obese. Neither BMI (hazard ratio [HR], 0.99; 95% CI, 0.97-1.01; P = .41) nor obesity (HR, 1.0; 95% CI, 0.99-1.01; P = .46) were associated with mortality in multivariable analyses. There was a significant interaction between age and obesity such that mortality increased among patients < 65 years of age who were morbidly obese (HR, 3.01; 95% CI, 1.56-5.79; P = .001).

CONCLUSIONS

Obesity was not associated with mortality in the overall population, but there was an age-obesity interaction with increased mortality among young patients who were morbidly obese. These results have implications for active weight management in younger patients who are morbidly obese who are otherwise candidates for lung transplantation.

Dart to the target: an alternative bull's eye parametric display for European Society of Cardiology / European Respiratory Society goal-orientated risk reduction strategy in pulmonary arterial hypertension

Despite the significant mortality and mobidity benefits being obtained with the targeted therapies in patients with pulmonary arterial hypertension (PAH), mid- to long-term survival of patients with this disease has remained unsatisfactory. For earlier and reliable risk stratification in PAH and tailoring the dynamic management strategies, various risk assessment models have been developed. Currently available risk reduction strategy recommended by the European Society of Cardiology (ESC)/European Respiratory Society (ERS) 2015 Pulmonary Hypertension Guidelines has been utilized in three recent registries. In this review, we evaluated the risk prediction models and management algorithms in this setting and propose an alternative parametric display, a bull's eye, dart table scheme for ESC/ERS goal-orientated risk reduction strategy in patients with PAH.

Mortality in Patients With Pulmonary Arterial Hypertension Treated With Continuous Prostanoids

BACKGROUND

Parenteral prostanoids are considered the treatment of choice for patients with severe pulmonary arterial hypertension (PAH). Prognostic studies for patients treated in the modern era are limited.

METHODS

In this retrospective cohort study, patients initiating IV epoprostenol or IV or subcutaneous (SC) treprostinil therapy for PAH from 2007 to 2016 at UT Southwestern and The Ohio State University were included. Transplant-free survival was assessed from the time of IV/SC therapy initiation and from the time of first follow-up. The utility of traditional prognostic measures was assessed by using categories (lower, intermediate, and higher risk) recommended in the 2015 European Society of Cardiology/European Respiratory Society guidelines for functional class, 6-min walk distance, brain natriuretic peptide or N-terminal pro-brain natriuretic peptide level, and hemodynamic results.

RESULTS

Patients with group 1 PAH receiving IV epoprostenol (n = 132), IV treprostinil (n = 25), or SC treprostinil (n = 38) were included. Survival from IV/SC prostanoid initiation was 84%, 77%, and 67% at 1, 2, and 3 years. Follow-up assessment was performed after a minimum of 90 days' therapy (mean, 356 ± 247 days) in 163 patients. After treatment with an IV/SC prostanoid, better functional class, 6-min walk distance, brain natriuretic peptide/N-terminal pro-brain natriuretic peptide level, and mixed venous O₂ saturation (but not cardiac index) was associated with survival, as was the total number of lower risk and higher risk findings. Having zero lower risk findings or two or more higher risk findings was associated with particularly poor outcomes.

CONCLUSIONS

In patients with PAH receiving treatment with a parenteral prostanoid, survival was significantly associated with the number of guideline-recommended lower risk and higher risk criteria achieved at first follow-up.