The impact of cardiovascular and lung comorbidities in patients with pulmonary arterial hypertension: A systematic review and meta-analysis.

BACKGROUND: Contemporary patients with pulmonary arterial hypertension (PAH) are older and exhibit cardiovascular or/and lung comorbidities. Such patients have typically been excluded from major PAH drug trials. This systematic review compares baseline characteristics, hemodynamic parameters, and mortality rate between PAH patients with significant number of comorbidities compared to those with fewer or no comorbidities. ΜETHODS: A systematic literature search in PubMed, Web of Science, and Cochrane databases was conducted searching for studies comparing PAH patients with more than 2 cardiovascular comorbidities or/and at least a lung comorbidity against those with fewer comorbidities. RESULTS: Seven observational studies were included. PAH patients with comorbidities were older, with an almost equal female-to-male ratio, shorter 6-minute walk distance, higher N-terminal pro-brain natriuretic peptide levels, and lower lung diffusion for carbon monoxide. In terms of hemodynamics, they had higher mean right atrial pressure and pulmonary artery wedge pressure, lower mean pulmonary arterial pressure, pulmonary vascular resistance and mixed venous oxygen saturation. Pooled analysis of 6 studies demonstrated a higher mortality risk for PAH patients with comorbidities compared to those without (HR 1.86, 95% CI 1.20 to 2.89, p < 0.001, I²=92%), with the subgroup of PAH patients with lung comorbidities having an even higher mortality risk (test for subgroup differences: p < 0.001). Combination drug therapy for PAH was less frequently used in patients with comorbidities. CONCLUSIONS: Cardiovascular and lung comorbidities impact the clinical characteristics and outcomes of PAH patients, highlighting the need for optimal phenotyping and tailored management for this high-risk population.

Chaotic breathing in post-COVID-19 breathlessness: a key feature of dysfunctional breathing can be characterised objectively by approximate entropy.

Post-COVID-19 breathing pattern disorder can be characterised by application of nonlinear statistical modelling of exercise ventilatory data https://bit.ly/3WlBc7e.

Autoimmunity Is a Significant Feature of Idiopathic Pulmonary Arterial Hypertension.

Rationale: Autoimmunity is believed to play a role in idiopathic pulmonary arterial hypertension (IPAH). It is not clear whether this is causative or a bystander of disease and if it carries any prognostic or treatment significance. Objectives: To study autoimmunity in IPAH using a large cross-sectional cohort. Methods: Assessment of the circulating immune cell phenotype was undertaken using flow cytometry, and the profile of serum immunoglobulins was generated using a standardized multiplex array of 19 clinically validated autoantibodies in 473 cases and 946 control subjects. Additional glutathione S-transferase fusion array and ELISA data were used to identify a serum autoantibody to BMPR2 (bone morphogenetic protein receptor type 2). Clustering analyses and clinical correlations were used to determine associations between immunogenicity and clinical outcomes. Measurements and Main Results: Flow cytometric immune profiling demonstrates that IPAH is associated with an altered humoral immune response in addition to raised IgG3. Multiplexed autoantibodies were significantly raised in IPAH, and clustering demonstrated three distinct clusters: "high autoantibody," "low autoantibody," and a small "intermediate" cluster exhibiting high concentrations of ribonucleic protein complex. The high-autoantibody cluster had worse hemodynamics but improved survival. A small subset of patients demonstrated immunoglobulin reactivity to BMPR2. Conclusions: This study establishes aberrant immune regulation and presence of autoantibodies as key features in the profile of a significant proportion of patients with IPAH and is associated with clinical outcomes.

Mendelian randomisation and experimental medicine approaches to interleukin-6 as a drug target in pulmonary arterial hypertension.

BACKGROUND: Inflammation and dysregulated immunity are important in the development of pulmonary arterial hypertension (PAH). Compelling preclinical data supports the therapeutic blockade of interleukin-6 (IL-6) signalling. METHODS: We conducted a phase 2 open-label study of intravenous tocilizumab (8 mg·kg-1) over 6 months in patients with group 1 PAH. Co-primary end-points were safety, defined by incidence and severity of adverse events, and change in pulmonary vascular resistance. Separately, a mendelian randomisation study was undertaken on 11 744 individuals with European ancestry including 2085 patients with idiopathic/heritable disease for the IL-6 receptor (IL6R) variant (rs7529229), known to associate with circulating IL-6R levels. RESULTS: We recruited 29 patients (male/female 10/19; mean±sd age 54.9±11.4 years). Of these, 19 had heritable/idiopathic PAH and 10 had connective tissue disease-associated PAH. Six were withdrawn prior to drug administration; 23 patients received at least one dose of tocilizumab. Tocilizumab was discontinued in four patients owing to serious adverse events. There were no deaths. Despite evidence of target engagement in plasma IL-6 and C-reactive protein levels, both intention-to-treat and modified intention-to-treat analyses demonstrated no change in pulmonary vascular resistance. Inflammatory markers did not predict treatment response. Mendelian randomisation did not support an effect of the lead IL6R variant on risk of PAH (OR 0.99, p=0.88). CONCLUSION: Adverse events were consistent with the known safety profile of tocilizumab. Tocilizumab did not show any consistent treatment effect.

Pulmonary arterial hypertension in adults with congenital heart disease: markers of disease severity, management of advanced heart failure and transplantation.

INTRODUCTION: Pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) is a progressive, life-limiting disease. AREAS COVERED: In this paper, we review the classification and pathophysiology of PAH-CHD, including the mechanisms of disease progression and multisystem effects of disease. We evaluate current strategies of risk stratification and the use of biological markers of disease severity, and review principles of management of PAH-CHD. The indications, timing, and the content of advanced heart failure assessment and transplant listing are discussed, along with a review of the types of transplant and other forms of available circulatory support in this group of patients. Finally, the integral role of advance care planning and palliative care is discussed. EXPERT OPINION/COMMENTARY: All patients with PAH-CHD should be followed up in expert centers, where they can receive appropriate risk assessment, PAH therapy, and supportive care. Referral for transplant assessment should be considered if there continue to be clinical high-risk features, persistent symptoms, or acute heart failure decompensation despite appropriate PAH specific therapy. Expert management of PAH-CHD patients, therefore, requires vigilance for these features, along with a close relationship with local advanced heart failure services and a working knowledge of listing criteria, which may disadvantage congenital heart disease patients.

Establishing expert consensus for the optimal approach to holistic risk-management in pulmonary arterial hypertension: a Delphi process and narrative review.

Background: Pulmonary arterial hypertension (PAH) is associated with significant morbidity and reduced life expectancy. Various medical therapies, together with non-medical therapies such as exercise training, have been shown to improve outcomes for patients. We performed a Delphi consensus process to establish optimal approaches to optimizing patient care.Methods: A steering group of PAH experts formulated 38 statements grouped into 6 themes: burden of PAH, risk-stratification, the role of clinical phenotyping in the management of PAH, assessing clinical response to treatment, maximizing the medical treatment pathway and the role of other management options. An online survey was sent to PAH health-care professionals throughout the UK to assess consensus with these statements. Consensus was defined as high if ≥70% and very high if ≥90% of the respondents agreed with a statement. A narrative review for each theme was then performedResults: Consensus was very high in 27 (71%) statements, high in 7 (18%) statements and was not achieved in 4 (11%) statements.Conclusions: Based on the consensus scores, the steering group derived 13 recommendations which, if implemented, should result in improved holistic care of patients with PAH.

EmPHasis-10 health-related quality of life score predicts outcomes in patients with idiopathic and connective tissue disease-associated pulmonary arterial hypertension: results from a UK multicentre study.

Health-related quality of life (HRQoL) scores assess symptom burden in pulmonary arterial hypertension (PAH) but data regarding their role in prognostication and risk stratification are limited. We assessed these relationships using the emPHasis-10 HRQoL measure.1745 patients with idiopathic PAH (IPAH), drug-induced PAH (DPAH), heritable PAH (HPAH) (collectively "(I/D/H)PAH"), or connective tissue disease-associated PAH (CTD-PAH), who had completed emPHasis-10 questionnaires at one of six UK referral centres between 2014 and 2017, were identified. Correlations with exercise capacity and World Health Organization (WHO) functional class were assessed, and exploratory risk stratification thresholds were tested.Moderate correlations were seen between emPHasis-10 scores and 6-min walk distance (r=-0.546), incremental shuttle walk distance (r=-0.504) and WHO functional class (r=0.497) (all p<0.0001). Distribution of emPHasis-10 score differed significantly between each WHO functional class (all p<0.0001). On multivariate analysis, emPHasis-10 score, but not WHO functional class, was an independent predictor of mortality. In a risk stratification approach, scores of 0-16, 17-33 and 34-50 identified incident patients with 1-year mortality of 5%, 10% and 23%, respectively. Survival of patients in WHO functional class III could be further stratified using an emPHasis-10 score ≥34 (p<0.01). At follow-up, patients with improved emPHasis-10 scores had improved exercise capacity (p<0.0001) and patients who transitioned between risk groups demonstrated similar survival to patients originally in those risk groups.The emPHasis-10 score is an independent prognostic marker in patients with (I/D/H)PAH or CTD-PAH. It has utility in risk stratification in addition to currently used parameters. Improvement in emPHasis-10 score is associated with improved exercise capacity.

Pulmonary Angiopathy in Severe COVID-19: Physiologic, Imaging, and Hematologic Observations.

Rationale: Clinical and epidemiologic data in coronavirus disease (COVID-19) have accrued rapidly since the outbreak, but few address the underlying pathophysiology.Objectives: To ascertain the physiologic, hematologic, and imaging basis of lung injury in severe COVID-19 pneumonia.Methods: Clinical, physiologic, and laboratory data were collated. Radiologic (computed tomography (CT) pulmonary angiography [n = 39] and dual-energy CT [DECT, n = 20]) studies were evaluated: observers quantified CT patterns (including the extent of abnormal lung and the presence and extent of dilated peripheral vessels) and perfusion defects on DECT. Coagulation status was assessed using thromboelastography.Measurements and Results: In 39 consecutive patients (male:female, 32:7; mean age, 53 ± 10 yr [range, 29-79 yr]; Black and minority ethnic, n = 25 [64%]), there was a significant vascular perfusion abnormality and increased physiologic dead space (dynamic compliance, 33.7 ± 14.7 ml/cm H2O; Murray lung injury score, 3.14 ± 0.53; mean ventilatory ratios, 2.6 ± 0.8) with evidence of hypercoagulability and fibrinolytic "shutdown". The mean CT extent (±SD) of normally aerated lung, ground-glass opacification, and dense parenchymal opacification were 23.5 ± 16.7%, 36.3 ± 24.7%, and 42.7 ± 27.1%, respectively. Dilated peripheral vessels were present in 21/33 (63.6%) patients with at least two assessable lobes (including 10/21 [47.6%] with no evidence of acute pulmonary emboli). Perfusion defects on DECT (assessable in 18/20 [90%]) were present in all patients (wedge-shaped, n = 3; mottled, n = 9; mixed pattern, n = 6).Conclusions: Physiologic, hematologic, and imaging data show not only the presence of a hypercoagulable phenotype in severe COVID-19 pneumonia but also markedly impaired pulmonary perfusion likely caused by pulmonary angiopathy and thrombosis.

Idiopathic pulmonary arterial hypertension and co-existing lung disease: is this a new phenotype?

Patients classified as idiopathic pulmonary arterial hypertension (defined as Group 1 on European Respiratory Society (ERS)/European Cardiac Society (ESC) criteria) may have evidence of minor co-existing lung disease on thoracic computed tomography. We hypothesised that these idiopathic pulmonary arterial hypertension patients (IPAH lung disease ) are a separate subgroup of idiopathic pulmonary arterial hypertension with different phenotype and outcome compared with idiopathic pulmonary arterial hypertension patients without co-existing lung disease (IPAH no lung disease ). Patients with 'IPAH lung disease ' have been eligible for all clinical trials of Group 1 patients because they have normal clinical examination and normal spirometry but we wondered whether they responded to treatment and had similar survival to patients with 'IPAH no lung disease '. We described the outcome of the cohort of patients with 'IPAH no lung disease ' in a previous paper. Here, we have compared incident 'IPAH lung disease ' patients with 'IPAH no lung disease ' patients diagnosed concurrently in all eight Pulmonary Hypertension centres in the UK and Ireland between 2001-2009. Compared with 'IPAH no lung disease ' (n = 355), 'IPAH lung disease ' patients (n = 137) were older, less obese, predominantly male, more likely to be current/ex-smokers and had lower six-minute walk distance, lower % predicted diffusion capacity for carbon monoxide, lower mean pulmonary arterial pressure and lower pulmonary vascular resistance index. After three months of pulmonary hypertension-targeted treatment, six-minute walk distance improved equally in 'IPAH lung disease ' and 'IPAH no lung disease '. However, survival of 'IPAH lung disease ' was lower than 'IPAH no lung disease ' (one year survival: 72% compared with 93%). This survival was significantly worse in 'IPAH lung disease ' even after adjusting for age, gender, smoking history, comorbidities and haemodynamics. 'IPAH lung disease ' patients had similar short-term improvement in six-minute walk distance with anti-pulmonary arterial hypertension therapy but worse survival compared with 'IPAH no lung disease ' patients. This suggests that 'IPAH lung disease ' are a separate phenotype and should not be lumped with 'IPAH no lung disease ' in clinical trials of Group 1 pulmonary arterial hypertension.

Right Ventricular to Left Ventricular Ratio at CT Pulmonary Angiogram Predicts Mortality in Interstitial Lung Disease.

BACKGROUND: Patients with interstitial lung disease (ILD) may develop pulmonary hypertension (PH), often disproportionate to the severity of the ILD. The right ventricular to left ventricular diameter (RV:LV) ratio measured at CT pulmonary angiogram (CTPA) has been shown to provide valuable information in patients with pulmonary arterial hypertension and to predict death or deterioration in acute pulmonary embolism. METHODS: Demographic characteristics, ILD subtype, echocardiography, and detailed CTPA measurements were collected in consecutive patients undergoing both CTPA and right heart catheterization at the Royal Brompton Hospital between 2005 and 2015. Fibrosis severity was formally scored according to CT criteria. The RV:LV ratio at CTPA was evaluated by using three different methods. Cox proportional hazards analysis was used to assess the relation of CTPA-derived parameters to predict death or lung transplantation. RESULTS: A total of 92 patients were included (64% male; mean age 65 ± 11 years) with an FVC 57 ± 20% predicted, corrected transfer factor of the lung for carbon monoxide 22 ± 8% predicted, and corrected transfer coefficient of the lung for carbon monoxide 51 ± 17% predicted. PH was confirmed at right heart catheterization in 78%. Of all the CTPA-derived measures, an RV:LV ratio ≥ 1.0 strongly predicted mortality or transplantation at univariate analysis (hazard ratio, 3.26; 95% CI, 1.49-7.13; P = .003), whereas invasive hemodynamic data did not. The RV:LV ratio remained an independent predictor at multivariate analysis (hazard ratio, 3.19; 95% CI, 1.44-7.10; P = .004), adjusting for an ILD diagnosis of idiopathic pulmonary fibrosis and CT imaging-derived ILD severity. CONCLUSIONS: An increased RV:LV ratio measured at CTPA provides a simple, noninvasive method of risk stratification in patients with suspected ILD-PH. This should prompt closer follow-up, more aggressive treatment, and consideration of lung transplantation.

Chronic thromboembolic pulmonary hypertension following long-term peripherally inserted central venous catheter use.

A 36-year-old woman presented with recurrent pulmonary emboli (PE) despite oral anticoagulation. She was a type I diabetic with severe gastroparesis requiring insertion of multiple long-term peripherally inserted central catheters (PICC) over a 10-year period. Imaging at presentation demonstrated a PICC-associated mobile mass in the right atrium and signs of pulmonary hypertension (PH). She was thrombolyzed and fully anticoagulated, and diabetic management without PICC strongly recommended. PH persisted, however, and she developed chronic thromboembolic pulmonary hypertension (CTEPH), for which successful pulmonary endarterectomy (PEA) surgery led to symptomatic and hemodynamic improvement. This was the first case of CTEPH reported related to long-term PICC use outside the setting of malignant disease, and a novel observation that the PEA specimen contained multiple plastic fragments. Long-term PICC placement increases the risk of CTEPH, a life-threatening, albeit treatable, complication.

Early histological changes of pulmonary arterial hypertension disclosed by invasive cardiopulmonary exercise testing.

Early diagnosis of pulmonary artery hypertension (PAH) is diagnostically challenging given the extent of pulmonary vascular remodeling required to bring about clinical signs and symptoms. Exercise testing can be invaluable in this setting, as stressing the cardiopulmonary system may unmask early disease. This report describes a young patient with a positive family history of PAH in whom contemporaneous invasive cardiopulmonary exercise testing and surgical lung biopsy reveal the novel association between exercise pulmonary hypertension (ePH) and early histological changes of PAH. Exercise PH currently carries no pathological correlates which means the hemodynamic effects of early pulmonary vascular remodeling remain unknown. Following the recent proceedings from the World Symposium in Pulmonary Hypertension 2018, which broaden the hemodynamic definition of PAH, this report suggests an important association between ePH and early pulmonary vascular remodeling supporting a role for exercise hemodynamic evaluation in patients at increased familial risk of PAH.

Tumoral pulmonary hypertension.

Tumoral pulmonary hypertension (PH) comprises a variety of subtypes in patients with a current or previous malignancy. Tumoral PH principally includes the tumour-related pulmonary microvascular conditions pulmonary tumour microembolism and pulmonary tumour thrombotic microangiopathy. These inter-related conditions are frequently found in post mortem specimens but are notoriously difficult to diagnose ante mortem The outlook for patients remains extremely poor although there is some emerging evidence that pulmonary vasodilators and anti-inflammatory approaches may improve survival. Tumoral PH also includes pulmonary macroembolism and tumours that involve the proximal pulmonary vasculature, such as angiosarcoma; both may mimic pulmonary embolism and chronic thromboembolic PH. Finally, tumoral PH may develop in response to treatments of an underlying malignancy. There is increasing interest in pulmonary arterial hypertension induced by tyrosine kinase inhibitors, such as dasatanib. In addition, radiotherapy and chemotherapeutic agents such as mitomycin-C can cause pulmonary veno-occlusive disease. Tumoral PH should be considered in any patient presenting with unexplained PH, especially if it is poorly responsive to standard approaches or there is a history of malignancy. This article will describe subtypes of tumoral PH, their pathophysiology, investigation and management options in turn.