Risk stratification in pulmonary arterial hypertension

Frequency, characteristics and risk assessment of pulmonary arterial hypertension with a left heart disease phenotype

AIM

To obtain real-world evidence about the features and risk stratification of pulmonary arterial hypertension (PAH) with a left heart disease (LHD) phenotype (PAH-LHD).

METHODS AND RESULTS

By reviewing the records of consecutive incident PAH patients at 7 tertiary centers from 2001 to 2021, we selected 286 subjects with all parameters needed to determine risk of death at baseline and at first follow-up with COMPERA and COMPERA 2.0 scores. Fifty seven (20%) had PAH-LHD according to the AMBITION definition. Compared with no-LHD ones, they were older, had higher BMI, more cardiovascular comorbidities, higher E/e' ratio and left atrial area, but lower BNP concentrations and better right ventricular function and pulmonary hemodynamics. Survival was comparable between PAH-LHD and no-LHD patients, although the former were less commonly treated with dual PAH therapy. Both COMPERA and COMPERA 2.0 discriminated all-cause mortality risk of PAH-LHD at follow-up, but not at baseline. Risk profile significantly improved during follow-up only when assessed by COMPERA 2.0. At multivariable analysis with low-risk status as reference, intermediate-high and high-risk, but not LHD phenotype, were associated with higher hazard of all-cause mortality. Results were comparable in secondary analyses including patients in the last 10 years and atrial fibrillation and echocardiographic abnormalities as additional criteria for PAH-LHD.

CONCLUSIONS

In real life, PAH-LHD patients are frequent, have less severe disease and are less likely treated with PAH drug combinations than no-LHD. The COMPERA 2.0 model may be more appropriate to evaluate their mortality risk during follow-up and how it is modulated by therapy.

Pharmacotherapy of refractory pulmonary arterial hypertension

INTRODUCTION

Treatment of refractory pulmonary arterial hypertension (PAH) is challenging and rarely the focus of reviews. The purpose of this review is to discuss current treatment options of refractory PAH, along with the state of research of several new medications.

AREAS COVERED

We conducted a comprehensive PubMed search on the relevant literature on treating PAH, with a focus on approved and investigational interventions for high-risk patients. Our strategy used keywords 'Treatment' AND 'Pulmonary Hypertension,' without date restrictions, ensuring a thorough survey of available literature for our review.

EXPERT OPINION

By utilizing serial risk assessment to identify patients remaining intermediate or high-risk, more patients are likely to survive longer. This is done by earlier use of combination or triple therapy with prostacyclin drugs. Current medications for PAH are all essentially vasodilators that improve physiology, but do not truly modify the disease process. The potential application of new investigational medications is exciting as they work by novel pathways likely to change the landscape of refractory PAH treatment.

Novel Drugs for the Treatment of Pulmonary Arterial Hypertension: Where Are We Going?

Pulmonary arterial hypertension (PAH) is a progressive disease that despite advances in therapy is associated with a 7-year survival of approximately 50%. Several risk factors are associated with developing PAH, include methamphetamine use, scleroderma, human immunodeficiency virus, portal hypertension, and genetic predisposition. PAH can also be idiopathic. There are traditional pathways underlying the pathophysiology of PAH involving nitric oxide, prostacyclin, thromboxane A2, and endothelin-1, resulting in impaired vasodilation, enhanced vasoconstriction and proliferation in the pulmonary vasculature. Established PAH medications targets these pathways; however, this paper aims to discuss novel drugs for treating PAH by targeting new and alternative pathways.

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.

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.

[Risk Stratification in Patients with Pulmonary Arterial Hypertension under Treatment - Results of Four German Centers]

Risk stratification plays an essential role in the management of patients with pulmonary arterial hypertension (PAH). According to the current European guidelines the expected 1-year risk of mortality for PAH patients can be categorized as low, intermediate, or high, based on clinical, non-invasive and hemodynamic data.Data from 131 patients with incident PAH (age 64 ± 14) and frequent comorbidities (in 66.4 %) treated between 2016 and 2018 at 4 German PH centers were analyzed. At baseline, most patients were classified as intermediate risk (76 %), 13.8 % as high risk and only 9.9 % as low risk.During follow-up while on treatment after 12 ± 3 months (range 9-16 months) 64.9 % were still classified as intermediate risk (76 %), 14.4 % as high risk and 20.7 % as low risk.Survival at 12 and 24 months was 96 % and 82 % in the intermediate risk group, while only 89 % and 51 % of the high risk patients were alive at these time points. In contrast, all patients in the low risk category were alive at 24 months.Despite the availability of various treatment options for patients with PAH even in specialized centers only a minority of patients can be stabilized in the low risk group associated with a good outcome.

New prognostic markers in pulmonary arterial hypertension: CRP to albumin ratio and uric acid

INTRODUCTION

Idiopathic pulmonary hypertension(IPAH) is a rare disease that causes severe morbidity and mortality despite advances in treatment management. Evaluating the prognosis of the disease is critical in determining therapeutic approaches. We aimed to evaluate the prognostic significance of C-reactive protein/albumin ratio (CAR) and uric acid, which is an easily applicable and inexpensive parameter in patients with IPAH.

METHODS

Seventy-two IPAH patients and 99 consecutive non-IPAH patients as a control group were enrolled in the study retrospectively. Right heart catheterization(RHC), echocardiography, and laboratory parameters of the two groups and those who died and survived among the IPAH patients were compared.

RESULTS

IPAH and control group were compared at the first stage and CAR (1.98(0.28-10.74), 0.75(0.22-4.7),respectively;p < 0.01) and uric acid (0.33(0.19-0.87), 0.3(0.11-0.48) mmol/L, respectively; p = 0.03) values were significantly higher in the pulmonary hypertension group compared to the control group. Compared with the surviving IPAH patients, CAR (4.60(1.39-10.74),1.54(0.28-6.74),respectively;p < 0.001) and uric acid levels (0.458(0.26-0.87), 0.315(0.19-0.56) mmol/L, respectively; p < 0.001) were significantly higher in the group of patients who died. In the multivariate Cox regression models uric acid(p < 0.001) and CAR(p < 0.001) were found to be associated with survival time. Receiver operating characteristic curves (ROC) analyses showed that > 1.54 CAR value (AUC = 0.81,Sens:85.7%,Spec:56.9%,p < 0.001) and > 5.85 mg/dL (>0.348 mmol/L) uric acid value (AUC = 0.864, Sens:85.7%, Spec:78.4%, p < 0.001) are strong predictors for mortality.

CONCLUSION

In this study, we showed that simple markers such as CAR, which augment the inflammation marker feature of CRP, and uric acid can give prognostic information in PAH patients.

Novel molecular insights and public omics data in pulmonary hypertension

Pulmonary hypertension is a rare disease with high morbidity and mortality which mainly affects women of reproductive age. Despite recent advances in understanding the pathogenesis of pulmonary hypertension, the high heterogeneity in the presentation of the disease among different patients makes it difficult to make an accurate diagnosis and to apply this knowledge to effective treatments. Therefore, new studies are required to focus on translational and personalized medicine to overcome the lack of specificity and efficacy of current management. Here, we review the majority of public databases storing 'omics' data of pulmonary hypertension studies, from animal models to human patients. Moreover, we review some of the new molecular mechanisms involved in the pathogenesis of pulmonary hypertension, including non-coding RNAs and the application of 'omics' data to understand this pathology, hoping that these new approaches will provide insights to guide the way to personalized diagnosis and treatment.

Portopulmonary hypertension: prognosis and management in the current treatment era - results from the REHAP registry

BACKGROUND

Portopulmonary hypertension (PoPH) is a rare condition with poorer survival compared to idiopathic/familial pulmonary arterial hypertension (IPAH/FPAH).

AIMS

To compare the characteristics, survival, prognostic factors and management of PoPH and IPAH/FPAH patients and to assess the impact of treatment on survival of PoPH patients.

METHODS

Analysis of data of prevalent and incident PoPH patients enrolled in the Spanish registry of PAH (REHAP) from January 1998 to December 2017 and comparison with IPAH/FPAH patients. Variables analysed: patient and disease (PAH and liver) characteristics, first-line PAH-targeted therapy, causes of death, prognostic factors and survival (according to aetiology and treatment in PoPH patients).

RESULTS

Compared to IPAH/FPAH patients (n = 678), patients with PoPH (n = 237) were predominantly men, older and had better functional class and higher prevalence of ascites. Haemodynamics were better. Biomarkers for heart failure were worse. Age- and sex-adjusted 5-year survival rate from diagnosis was 49.3% for PoPH patients and 68.7% for IPAH patients (P < 0.001). Treated PoPH had better survival than non-treated. PAH- and liver-related causes accounted for 30.2% and 24.7% of deaths in PoPH patients. PoPH patients were less likely to receive first-line PAH-targeted therapy and this was associated with greater mortality. Increasing age, worse exercise capacity and ascites were independent prognostic factors of poorer survival; first-line oral monotherapy was associated with improved survival. Eight (3.4%) PoPH patients underwent liver transplantation.

CONCLUSIONS

PoPH patients are undertreated and show poorer survival than IPAH/FPAH patients. First-line treatment with PAH-targeted therapy was associated with better survival. Presence of ascites was a predictor of mortality.

Monotherapy in patients with pulmonary arterial hypertension at four German PH centres

BACKGROUND

Although combination therapy is the gold standard for patients with pulmonary arterial hypertension (PAH), some of these patients are still being treated with monotherapy.

METHODS

We conducted a retrospective analysis at four German PH centres to describe the prevalence and characteristics of patients receiving monotherapy.

RESULTS

We identified 131 incident PAH patients, with a mean age of 64 ± 13.8 years and a varying prevalence of comorbidities, cardiovascular risk factors and targeted therapy. As in other studies, the extent of prescribed PAH therapy varied with age and coexisting diseases, and younger, so-called "typical" PAH patients were more commonly treated early with combination therapy (48% at 4-8 months). In contrast, patients with multiple comorbidities or cardiovascular risk factors were more often treated with monotherapy (69% at 4-8 months). Survival at 12 months was not significantly associated with the number of PAH drugs used (single, dual, triple therapy) and was not different between "atypical" and "typical" PAH patients (89% vs. 85%).

CONCLUSION

Although "atypical" PAH patients with comorbidities or a more advanced age are less aggressively treated with respect to combination therapy, the outcome of monotherapy in these patients appears to be comparable to that of dual or triple therapy in "typical" PAH patients.

Portopulmonary Hypertension: Prevalence, Clinical and Hemodynamic Features

Portopulmonary hypertension (PoPH) is a vascular complication of portal hypertension. This study aims to identify the prevalence and analyzing the clinical and hemodynamic features of patients with PoPH from a cohort of pulmonary arterial hypertension (PAH) patients. A retrospective transversal descriptive and analytical study. Patients with PoPH taken from a PAH cohort. We compare with those reported in the literature. We found prevalence of 6.1% of 244 consecutive patients with PAH, 11 females and 4 males. The mean age was 62 years and the main etiology of portal hypertension was primary biliary cirrhosis. Statistical differences were found in mean pulmonary arterial pressure, pulmonary vascular resistance, right atrial pressure; we found levels lower than reported. We found significant differences in clinical and hemodynamic characteristics such as older age and hemodynamic parameters of less severity in the group of patients analyzed compared with reported data.

Incorporation of renal function in mortality risk assessment for pulmonary arterial hypertension

BACKGROUND

Risk assessment is important for prognostication and individualized treatment decisions for patients with pulmonary arterial hypertension (PAH). The purpose was (1) to compare contemporary risk assessment tools and (2) to determine the prognostic significance of risk parameters of kidney function and whether they can further improve risk prediction for patients with PAH.

METHODS

We identified a cohort of treatment-naive patients (n = 211) who received an incident diagnosis of PAH at the University of Ottawa Heart Institute. Using demographics, disease characteristics, and hemodynamic data at diagnosis, we categorized patients as low, intermediate, or high risk according to current European guidelines (European Society of Cardiology [ESC]) and registry to evaluate early and long-term pulmonary arterial hypertension disease management (REVEAL) risk scores. The primary end-point was transplant-free survival (TFS).

RESULTS

Patients were predominantly women (64.6%) with World Health Organization function Class III symptoms (66.5%). The median TFS was 7.09 years. There was little agreement between ESC- and REVEAL-based risk estimates (weighted kappa = 0.21-0.34). Although both the ESC (log-rank, p = 0.0002) and REVEAL algorithms stratified TFS risk (p < 0.0001), the REVEAL score provided superior discrimination (C-statistic = 0.70 vs 0.59, p = 0.004). Renal function at diagnosis (p < 0.0001) and Δ renal function at 6 months (p < 0.0001) were identified as novel risk parameters and served to reclassify some patients in the intermediate-risk category to a lower or higher risk stratum (p < 0.0001).

CONCLUSION

REVEAL-based strategies provide superior TFS risk discrimination to ESC/European Respiratory Society-based approaches. However, the classification of intermediate-risk patients varied significantly across tools. We demonstrate the importance of renal function, which further improved the stratification of risk in patients with PAH, particularly in patients who are considered intermediate risk.

Retrospective Validation of the REVEAL 2.0 Risk Score With the Australian and New Zealand Pulmonary Hypertension Registry Cohort

BACKGROUND

Pulmonary arterial hypertension (PAH) prognosis has improved with targeted therapies; however, the long-term outlook remains poor. Objective multiparametric risk assessment is recommended to identify patients at risk of early morbidity and mortality, and for optimization of treatment. The US Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL) 2.0 risk score is a new model proposed for the follow-up of patients with PAH but has not been externally validated.

METHODS

The REVEAL 2.0 risk score was applied to a mixed prevalent and incident cohort of patients with PAH (n = 1,011) from the Pulmonary Hypertension Society of Australia and New Zealand (PHSANZ) Registry. Kaplan-Meier survival was estimated for each REVEAL 2.0 risk score strata and for a simplified three-category (low, intermediate, and high risk) model. Sensitivity analysis was performed on an incident-only cohort.

RESULTS

The REVEAL 2.0 model effectively discriminated risk in the large external PHSANZ Registry cohort, with a C statistic of 0.74 (both for full eight-tier and three-category models). When applied to incident cases only, the C statistic was 0.73. The three-category REVEAL 2.0 model demonstrated robust separation of 12- and 60-month survival estimates (all risk category comparisons P < .001). Although the full eight-tier REVEAL 2.0 model separated patients at low, intermediate, and high risk, survival estimates overlapped within some of the intermediate- and high-risk strata.

CONCLUSIONS

The REVEAL 2.0 risk score was validated in a large external cohort from the PHSANZ Registry. The REVEAL 2.0 model can be applied for risk assessment of patients with PAH at follow-up. The simplified three-category model may be preferred for clinical use and for future comparison with other prognostic models.

[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.

The importance of right ventricular function in patients with pulmonary arterial hypertension

INTRODUCTION

Pulmonary arterial hypertension (PAH) is a progressive, life-threatening, and incurable disease. Its prognosis is based on right ventricular (RV) function. Therefore, adequate assessment of RV function is mandatory. Areas covered: This article presents the case of a patient with PAH in which the traditional diagnostic approach did not provide a complete assessment of RV function. The authors show how the analysis of other parameters yielded additional information that improved the management of this patient. Expert commentary: Despite current treatments, PAH often worsens due to progressive RV dysfunction. Appropriate assessment of RV function may facilitate the early identification of patients at risk of RV function impairment. More aggressive treatment of PAH might delay progression of the disease. Traditional risk stratification, which is based on New York Heart Association/World Health Organization (NYHA/WHO) functional class evaluation, the 6-minute walk test, and right heart catheterization, proves insufficient in many PAH patients, as it does not provide complete information about RV function. Thus, further parameters are required. Analysis of RV function, in addition to echocardiography and cardiopulmonary exercise testing, may add relevant prognostic information and improve therapy.