Embracing the challenges of neonatal and paediatric pulmonary hypertension.

Paediatric pulmonary arterial hypertension (PAH) shares common features with adult disease, but is associated with several additional disorders and challenges that require unique approaches. This article discusses recent advances, ongoing challenges and distinct approaches for caring for infants and children with PAH, as presented by the paediatric task force of the 7th World Symposium on Pulmonary Hypertension. We provide updates on diagnosing, classifying, risk-stratifying and treating paediatric pulmonary hypertension (PH) and identify critical knowledge gaps. An updated risk stratification tool and treatment algorithm is provided, now also including strategies for patients with associated cardiopulmonary conditions. Treatment of paediatric PH continues to be hindered by the lack of randomised controlled clinical trials. The challenging management of children failing targeted PAH therapy is discussed, including balloon atrial septostomy, lung transplantation and pulmonary-to-systemic shunt (Potts). A novel strategy using a multimodal approach for the management of PAH associated with congenital heart diseases with borderline pulmonary vascular resistance is included. Advances in diagnosing neonatal PH, especially signs and interpretation of PH by echocardiography, are highlighted. A team approach to the rapidly changing physiology of neonatal PH is emphasised. Challenges in drug approval are discussed, particularly the challenges of designing accurate paediatric clinical trials with age-appropriate end-points and adequate enrolment.

Progress in the treatment of acute pulmonary embolism and chronic thrombo-embolic pulmonary hypertension/disease.

The combination of an initial clinical approach aimed at evaluating the early risk of mortality with subsequent diagnostic and therapeutic approaches articulated on the overall patient's profile is recommended in acute pulmonary embolism (PE). The presence of pulmonary hypertension associated with the persistence of chronic vascular obstructions in the pulmonary arteries after one or more acute thrombo-embolic events identifies a condition defined as chronic thrombo-embolic pulmonary hypertension (CTEPH). The evolution of technology and knowledge in the field of imaging has allowed us to qualify the computed tomography angiography of the pulmonary arteries as the gold standard for the diagnostic confirmation of both acute PE and CTEPH. In both these conditions, the first therapeutic step is the immediate initiation of anticoagulant therapy. In acute high-risk PE, in addition to anticoagulant therapy, thrombolytic therapy is recommended; in the event of contraindications to thrombolysis, surgical embolectomy or percutaneous catheter-directed treatment represents viable treatment options. In CTEPH, the combination of data collected from cardiac catheterization, computed tomography angiography, and conventional angiography of pulmonary arteries allows a team of experts to identify candidates for pulmonary endarterectomy surgery. Inoperable patients should be considered for percutaneous balloon angioplasty of the pulmonary arteries which can improve patients' symptoms, quality of life, and prognosis.

Diagnosis of pulmonary hypertension.

A revised diagnostic algorithm provides guidelines for the diagnosis of patients with suspected pulmonary hypertension, both prior to and following referral to expert centres, and includes recommendations for expedited referral of high-risk or complicated patients and patients with confounding comorbidities. New recommendations for screening high-risk groups are given, and current diagnostic tools and emerging diagnostic technologies are reviewed.

Pulmonary arterial hypertension populations of special interest: portopulmonary hypertension and pulmonary arterial hypertension associated with congenital heart disease.

Guidelines exist for management of pulmonary arterial hypertension (PAH), but information is limited for certain patient subgroups, including adults with portopulmonary hypertension (PoPH) or with PAH associated with congenital heart disease (PAH-CHD). This article discusses screening, clinical management, and prognosis in PoPH and PAH-CHD and, as such, considers the most recent clinical data and expert advice. A multidisciplinary consultation and follow-up by specialists are crucial for management of both PoPH and PAH-CHD, but each condition presents with unique challenges. Development of PoPH most commonly occurs among patients with liver cirrhosis. Initially, patients may be asymptomatic for PoPH and, if untreated, survival with PoPH is generally worse than with idiopathic PAH (IPAH), so early identification with screening is crucial. PoPH can be managed with PAH-specific pharmacological therapy, and resolution is possible in some patients with liver transplantation. With PAH-CHD, survival rates are typically higher than with IPAH but vary across the four subtypes: Eisenmenger syndrome, systemic-to-pulmonary shunts, small cardiac defects, and corrected defects. Screening is also crucial and, in patients who undergo correction of CHD, the presence of PAH should be assessed immediately after repair and throughout their long-term follow-up, with frequency of assessments determined by the patient's characteristics at the time of correction. Early screening for PAH in patients with portal hypertension or CHD, and multidisciplinary management of PoPH or PAH-CHD are important for the best patient outcomes.

Combining bosentan and sildenafil in pulmonary arterial hypertension patients failing monotherapy: real-world insights.

Pulmonary arterial hypertension is a severe disease with a complex pathogenesis, for which combination therapy is an attractive option.This study aimed to assess the impact of sequential combination therapy on both short-term responses and long-term outcomes in a real-world setting.Patients with idiopathic/heritable pulmonary arterial hypertension, or pulmonary arterial hypertension associated with congenital heart disease or connective tissue disease and who were not meeting treatment goals on either first-line bosentan or sildenafil monotherapy, were given additional sildenafil or bosentan and assessed after 3-4 months. Double combination therapy significantly improved clinical and haemodynamic parameters, independent of aetiology or the order of drug administration. Significant improvements in functional class were observed in patients with idiopathic/heritable pulmonary arterial hypertension. The 1-, 3- and 5-year overall survival estimates were 91%, 69% and 59%, respectively. Patients with pulmonary arterial hypertension associated with connective tissue disease had significantly poorer survival rates compared to other aetiologies (p<0.003).The favourable short-term haemodynamic results and good survival rates, observed in patients receiving both bosentan and sildenafil, supports the use of sequential combination therapy in patients failing on monotherapy in a real-world setting.

Current era survival of patients with pulmonary arterial hypertension associated with congenital heart disease: a comparison between clinical subgroups.

AIMS: This study compared the clinical, functional, and haemodynamic characteristics and current era survival of subgroups of patients with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD): Eisenmenger syndrome (ES); PAH-CHD associated with systemic-to-pulmonary shunts (SPs); PAH with small defects (SDs); and PAH after defect correction (CDs). METHODS AND RESULTS: Data from consecutive PAH-CHD patients referred to our centre from 1 January 1998 to 31 May 2011 were collected. A contemporary group of idiopathic PAH patients was utilized for comparison. Treatment was per PAH guidelines, including combination therapy, with approved PAH-specific drugs. Survival was assessed with Kaplan-Meier analysis from the first invasive haemodynamic confirmation of PAH and compared across subgroups by log-rank test. Of 192 patients (mean age 41 ± 17 years; 61% female), 90 had ES (aged 41 ± 16 years); 48 SP (aged 47 ± 18 years); 10 SD (aged 25 ± 21 years); and 44 CD (aged 36 ± 17 years). Patients with ES had the highest baseline pulmonary vascular resistance and the lowest exercise capacity. Seventy-eight per cent were treated with approved PAH-specific drugs, and 44% were treated with combination therapy. Kaplan-Meier survival estimates (95% confidence interval) at 20 years for ES, SP, and CD were 87% (77-93%), 86% (60-96%), and 36% (12-72%, P = 0.0001 vs. ES; P = 0.004 vs. SP), respectively, and at 15 years for SD was 66% (16-91%, P = 0.015 vs. ES; P = 0.016 vs. SP). The survival of the 278 patients with idiopathic PAH appeared to be worse when compared with the PAH-CHD subgroups. CONCLUSION: Relevant clinical, functional, haemodynamic, and survival differences were observed among subgroups. In particular, patients with CD and SD had the worst survival. These findings should be considered when planning medical or interventional treatment strategies in PAH-CHD patients.

Pulmonary veno-occlusive disease: the role of CT.

OBJECTIVE: The authors sought to evaluate the diagnostic accuracy of high-resolution computed tomography (HRCT) in the detection of pulmonary veno-occlusive disease (PVOD) in patients with pre-capillary pulmonary arterial hypertension (PAH) of unknown aetiology, and to identify the role of CT in diagnosis and therapy. MATERIALS AND METHODS: The CT scans of 96 patients were retrospectively reviewed and assessed for specific HRCT findings: ground-glass opacities, septal lines and mediastinal lymph nodal enlargement (short diameter ≥1 cm). According to the HRCT findings, patients were divided into PVOD-suspicious and not PVOD-suspicious. Subsequently, a clinical-instrumental evaluation was performed, and the response to therapy and histopathological reports were evaluated. RESULTS: Radiological evaluation based on HRCT findings revealed 29 patients as PVOD-suspicious and 67 as not PVOD-suspicious. The final diagnosis was PVOD in 22 patients and idiopathic PAH in 74 patients. The CT scan showed 95.5 % sensitivity, 89% specificity, 72.5% positive predictive value, and 98.5% negative predictive value, with a diagnostic accuracy of 90.5% in identifying patients with PVOD. CONCLUSIONS: Chest CT can be considered a screening test in the assessment of patients with PAH of unknown aetiology, and the radiologist can help the clinician to identify patients with CT findings that make PVOD highly probable.

[Definitions and diagnosis of pulmonary hypertension]. / Pulmoner hipertansiyon tani ve tanimlar.

Pulmonary hypertension (PH) is defined by a mean pulmonary artery pressure 25 mm Hg at rest, measured during right heart catheterization. There is still insufficient .evidence to add an exercise criterion to this definition. The term pulmonary arterial hypertension (PAH) describes a subpopulation of patients with PH characterized hemodynamically by the presence of pre-capillary PH including an end-expiratory pulmonary artery wedge pressure (PAWP) 15 mm Hg and a pulmonary vascular resistance >3 Wood units. Right heart catheterization remains essential for a diagnosis of PH or PAH. This procedure requires further standardization, including uniformity of the pressure transducer zero level at the midthoracic line, which is at the level of the left atrium. One of the most common problems in the diagnostic workup of patients with PH is the distinction between PAH and PH due to left heart failure with preserved ejection fraction (HFpEF). A normal PAWP does not rule out the presence of HFpEF. Volume or exercise challenge during right heart catheterization may be useful to unmask the presence of left heart disease, but both tools require further evaluation before their use in general practice can be recommended. Early diagnosis of PAH remains difficult, and screening programs in asymptomatic patients are feasible only in high-risk populations, particularly in patients with systemic sclerosis, for whom recent data suggest that a combination of clinical assessment and pulmonary function testing including diffusion capacity for carbon monoxide, biomarkers, and echocardiography has a higher predictive value than echocardiography alone. (J Am Coll Cardiol 2013;62: D42-50) ©2013 by the American College of Cardiology Foundation.

Prognostic role of haemodynamics at follow-up in patients with pulmonary arterial hypertension: a challenge to current European Society of Cardiology/European Respiratory Society risk tools.

Background: Haemodynamic variables like right atrial pressure (RAP), cardiac index (CI), stroke volume index (SVI) and mixed venous oxygen saturation (S vO2 ) predict survival in patients with pulmonary arterial hypertension (PAH). However, there is the need to identify further prognostic haemodynamic parameters as well as to redefine their role in PAH risk stratification compared to current risk tools and non-invasive parameters. Methods: This cohort study includes treatment-naïve patients assessed at baseline and after first-line PAH therapy with clinical, functional, exercise, laboratory and haemodynamic evaluations. Using a stepwise multivariate Cox regression analysis, independent prognostic haemodynamic parameters were identified and stratified according to cut-offs already defined in the European Society of Cardiology (ESC)/European Respiratory Society (ERS) risk table or defined based on the highest Chi-squared of the log-rank test. Their discriminatory power was tested for all-cause death and a combined end-point of death, hospitalisation and need of treatment escalation. Results: 794 patients with PAH were enrolled. At first follow-up, RAP and pulmonary artery elastance were independently associated with death. Because of high correlations between haemodynamic parameters, different multivariable analyses were done identifying six other variables (pulmonary arterial compliance, cardiac efficiency, pulmonary vascular resistance, S vO2 , CI and SVI). Haemodynamic parameters were of no added prognostic value compared to ESC/ERS risk tools for the all-cause death end-point but they showed additional value to non-invasive parameters for the combined end-point and, when taken alone, had a discriminatory capacity comparable to ESC/ERS risk tools. Conclusion: Haemodynamics' discriminative ability for clinical worsening is comparable to current ESC/ERS risk tools and is of added value to non-invasive parameters.

Pulmonary Arterial Hypertension Associated with Portal Hypertension and HIV Infection: Comparative Characteristics and Prognostic Predictors.

BACKGROUND: Pulmonary arterial hypertension (PAH) may complicate both portal hypertension (Po-PAH) and HIV infection (HIV-PAH). These two conditions, however, frequently coexist in the same patient (HIV/Po-PAH). We evaluated clinical, functional, hemodynamic characteristics and prognostic parameters of these three groups of patients. METHODS: We included patients with Po-PAH, HIV-PAH and HIV/Po-PAH referred to a single center. We compared clinical, functional and hemodynamic parameters, severity of liver disease [Child-Turcotte-Pugh (CTP) and Model for End-stage Liver Disease-Na (MELD-Na) scores], CD4 count and highly active antiretroviral therapy (HAART) administration. Prognostic variables were identified through Cox-regression analysis. RESULTS: Patients with Po-PAH (n = 128) were the oldest, patients with HIV-PAH (n = 41) had the worst hemodynamic profile and patients with HIV/Po-PAH (n = 35) had the best exercise capacity. Independent predictors of mortality were age and CTP score for Po-PAH, HAART administration for HIV-PAH, MELD-Na score and hepatic venous-portal gradient for HIV/Po-PAH. CONCLUSIONS: Patients with HIV/Po-PAH are younger and have a better exercise capacity than patients with Po-PAH, have a better exercise capacity and hemodynamic profile compared to patients with HIV-PAH, and their prognosis seems to be related to the hepatic disease rather than to HIV infection. The prognosis of patients with Po-PAH and HIV-PAH seems to be related to the underlying disease.

Comparison of different treatment strategies in patients with chronic thromboembolic pulmonary hypertension: a single centre real-world experience.

BACKGROUND: Pulmonary endarterectomy (PEA) has been the most effective therapy for chronic thromboembolic pulmonary hypertension (CTEPH). However, there is a substantial proportion of patients deemed not operable in whom other treatment strategies are available: medical therapy and balloon pulmonary angioplasty (BPA). We aimed to compare different CTEPH treatment strategies effect in a real-world setting. METHODS: All patients with CTEPH referred to our centre were included. We compare the short-term clinical, functional, exercise and haemodynamic effect of medical therapy (irrespective of subsequent treatment strategies), PEA and BPA (irrespective of previous/subsequent treatment strategies); we also describe the long-term outcome of the different patient groups. RESULTS: We included 467 patients (39% were treated only with medical therapy, 43% underwent PEA, 13% underwent BPA and 5% were not treated with any therapy). Patients treated only with medical therapy were the oldest; compared to patients undergoing PEA, they had a lower exercise capacity, a higher risk profile and gained a lower haemodynamic, functional and survival benefit from the treatment. Patients undergoing BPA had a lower haemodynamic improvement but a comparable functional, exercise and risk improvement and a similar survival compared to patients undergoing PEA; their survival is anyway better than patients undergoing only medical treatment. Untreated historical control patients had the worst survival. CONCLUSIONS: We confirm the superiority of PEA compared to any alternative treatment in CTEPH patients and we observe that BPA, in patients deemed not operable or with persistent/recurrent PH after PEA, leads to a better outcome than medical therapy alone.

Lung neovascularity in pulmonary arterial hypertension associated with congenital heart defects and idiopathic pulmonary arterial hypertension: study of 198 patients.

OBJECTIVES: To correlate the severity of lung neovascularity (Sheehan vessels) with the cause and haemodynamic severity of pulmonary arterial hypertension (PAH), pulmonary artery (PA) size and heart disease type in patients with PH associated with congenital heart diseases (PAH-CHD) and idiopathic PH (IPAH). METHODS: We reviewed the HRCT and CT pulmonary angiography studies of 87 patients with PAH-CHD and 111 with IPAH; all had undergone right heart catheterisation. We evaluated the PA size and severity of neovascularity on CT. RESULTS: Neovascularity, which was found in 72% of PAH-CHD (56% with Eisenmenger's syndrome) and in 22% of IPAH patients, is significantly related to the severity of PH and all patients with severe neovascularity had intermediate or high PH. All PAH-CHD patients had a dilated PA with a greater risk of developing severe dilatation (diameter >5 cm). The neovascularity correlated with the PA size only in IPAH. CONCLUSIONS: Neovascularity even if not pathognomonic for PAH-CHD, is significantly more common in these patients, especially in Eisenmenger's syndrome. It is often the first CT sign to indicate the severity of PH in PAH-CHD and IPAH. A neovascularity ≥5 on CT indicates a intermediate or high PH. KEY POINTS: • Large retrospective studying specific lung disorders in patients with pulmonary arterial hypertension. • Neovascularity is often the first CT sign indicating the severity of pulmonary hypertension Alterations of lung parenchyma on CT in pulmonary hypertension are described • The first study to assess the severity of pulmonary hypertension by CT • If substantiated, CT might eventually replace some cardiac catheterisation for evaluating PH.

Early detection of pulmonary vascular disease in pulmonary arterial hypertension: time to move forward.

Pulmonary arterial hypertension (PAH) can be a rapidly progressive disorder and is associated with high rate of mortality, despite medical intervention. With the availability of effective therapy, early disease detection is an important strategic objective to improve treatment outcomes. Resting echocardiography is currently the recommended screening modality for high-risk population groups. However, it is clear that derangements in resting haemodynamics (and symptoms) are late sequelae of the pathobiological processes that begin in the distal pulmonary arteries. Exercise stress may unmask early pulmonary vascular dysfunction but the definition, clinical significance, and natural history of 'exercise PAH' remain undefined. We will review the currently available and potential future strategies aimed at early disease detection, and propose that ultimately the way forward is to detect disease at a stage prior to the rise in resting pulmonary artery pressure.

Therapeutic alternatives in chronic thromboembolic pulmonary hypertension: from pulmonary endarterectomy to balloon pulmonary angioplasty to medical therapy. State of the art from a multidisciplinary team.

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare disease with a very complex pathophysiology differing from other causes of pulmonary hypertension (PH). It is an infrequent consequence of acute pulmonary embolism that is frequently misdiagnosed. Pathogenesis has been related to coagulation abnormalities, infection or inflammation, although these disturbances can be absent in many cases. The hallmarks of CTEPH are thrombotic occlusion of pulmonary vessels, variable degree of ventricular dysfunction and secondary microvascular arteriopathy. The definition of CTEPH also includes an increase in mean pulmonary arterial pressure of more than 25 mmHg with a normal pulmonary capillary wedge of less than 15 mmHg. It is classified as World Health Organization group 4 PH, and is the only type that can be surgically cured by pulmonary endarterectomy (PEA). This operation needs to be carried out by a team with strong expertise, from the diagnostic and decisional pathway to the operation itself. However, because the disease has a very heterogeneous phenotype in terms of anatomy, degree of PH and the lack of a standard patient profile, not all cases of CTEPH can be treated by PEA. As a result, PH-directed medical therapy traditionally used for the other types of PH has been proposed and is utilized in CTEPH patients. Since 2015, we have been witnessing the rebirth of balloon pulmonary angioplasty, a technique first performed in 2001 but has since fallen out fashion due to major complications. The refinement of such techniques has allowed its safe utilization as a salvage therapy in inoperable patients. In the present keynote lecture, we will describe these therapeutic approaches and results.