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.

109 EFFICACY COMPARISON OF PROSTACYCLIN ANALOGUE AND PROSTACYCLIN RECEPTOR AGONIST AS THIRD LINE TREATMENT FOR PULMONARY ARTERIAL HYPERTENSION

Background

Pulmonary arterial hypertension (PAH) is a progressive disease characterized by small pulmonary arteries remodeling that leads to increased pulmonary vascular resistance, dyspnea, fatigue, right heart failure and ultimately death. Prostacyclin analogue drugs, such as epoprostenol or treprostinil, have a vasodilator, antiproliferative and immunomodulatory effect, representing established therapies for cases of severe PAH. Both these drugs improve exercise capacity, functional class and hemodynamic parameters, while epoprostenol also improves survival among patients with PAH. Despite these therapeutic benefits, these treatments need parenteral administration. Recently, the approval of selexipag, an oral selective prostacyclin receptor agonist, may represent a possible alternative option in some PAH patients.

Methods

patients with PAH treated as third line therapy with epoprostenol, treprostinil or selexipag, on top of inhibitor of type 5 phosphodiesterases and endothelin-1 receptor antagonists, referred to our center from February 1995 to December 2021 were retrospectively included. All patients noninvasive [6 minutes walking distance (6MWD)] and invasive [mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index (CI), right atrial pressure (RAP) and mixed venous oxygen saturation (SvO2)] parameters were first collected at the baseline right heart catheterization (prior to the beginning of prostacyclin treatment) and then 3-4 months after the beginning of third line therapy. The absolute improvements in these parameters were compared with Dunn's test. Data are expressed as median (interquartile range).

Results

153 PAH patients treated as third line therapy with epoprostenol, treprostenil and selexipag were included (44, 73, 36 patients respectively). At 3 to 4 months after the beginning of the third line therapy, improvements in the 6MWD were: 65 (25 - 132) m with epoprostenol, 16 (-8 - 63) m with treprostenil and 12 (-10 - 57) m with selexipag (p = 0.044). Absolute RAP reduction was -1 (-4–2.5) mmHg with epoprostenol, -1 (-3 - 2) mmHg with treprostenil and 0 (-4 - 2) mmHg with selexipag (p = 0.953). Absolute PAPm reduction was -5 (-9 - -1) mmHg with epoprostenol, -5 (-11 - -1) mmHg with treprostenil and -6.5 (-14 - 0) mmHg with selexipag (p = 0.670). Absolute CI improvement was 0.9 (0.4–1.1) l/min/m2 with epoprostenol, 0.5 (0.2–0.8) l/min/m2 with treprostenil and 0.3 (0.1 - 1) l/min/m2 with selexipag (p = 0.022). Absolute PVR improvement was -4.5 (-7.6 - -2) WU with epoprostenol, -3.2 (-4.9 - -1.7) WU with treprostenil and -2 (-4.4–0.9) WU with selexipag (p = 0.021). Absolute SvO2 increase was 4.8 (1.7–13.2) % with epoprostenol, 2.6 (-2.2–6.2) % with treprostenil and 2.3 (-2.4–7.5) % with selexipag (p = 0.036). For all three-way significant comparisons, the only pairwise comparisons with a p-value <0.05 were between epoprostenol vs the other two drugs.

Conclusions

in our study population, epoprostenol, treprostenil and selexipag improve both exercise capacity and haemodynamic parameters in PAH patients when used as third line therapy, with the highest efficacy in the first group and, possibly, the lowest efficacy in the latter. These results confirm the beneficial role of these drugs in PAH patients and may suggest a possible favorable role for selexipag in the management of PAH patients with a less severe disease reserving a more invasive treatment strategy with parenteral prostanoids in patients with a higher risk disease.

100 ANALYSIS OF PROGNOSTIC PREDICTORS AND DIFFERENCES BETWEEN SUBGROUPS OF PULMONARY ARTERIAL HYPERTENSION ASSOCIATED WITH PORTAL HYPERTENSION AND HIV INFECTION

Background

Pulmonary arterial hypertension (PAH) represents a rare complication of both portal hypertension (Po-PAH) and HIV infection (HIV-PAH). Due to overlapping risk factors, in the latter patients there may frequently be a hepatic involvement that can cause portal hypertension, resulting in an overlap PAH form associated with both portal hypertension and HIV (HIV/Po-PAH).

Methods

A retrospective analysis was conducted on 204 patients with Po-PAH (128), HIV-PAH (41) and HIV/Po-PAH (35) referred to our centre from 1993 to 2021, with the aim of describing the clinical, functional and haemodynamic characteristics and identifying the prognostic determinants. At baseline, in patients with Po-PAH and HIV/Po-PAH, the severity of liver disease was estimated using the Child-Turcotte-Pugh (CTP) score, MELD score (Model for End-stage Liver Disease); instead, in patients with HIV-PAH and HIV/Po-PAH it was defined whether they received HAART (Highly Active Anti-Retroviral Therapy) and the CD4+ lymphocytes number. Data are expressed as median (interquartile range) and compared with Dunn's test. Prognostic determinants were identified by univariate and multivariate Cox-regression analysis. Survival was assessed using Kaplan Meier method. Patients were treated according to ESC/ERS guidelines.

Results

HIV-infected patients [40 (37-43) years] and HIV/Po-PAH [44 (39-48) years] are younger than Po-PAH patients [53 (44-60) years]; the exercise capacity assessed by the 6-minute walking test of patients with HIV/Po-PAH [516 (432-571) m] was superior to both patients with Po-PAH [426 (366-504) m] and HIV-PAH [448 (370-510) m], presumably justified by the demographic and haemodynamic differences between these groups. In fact, patients with concomitant portal hypertension (Po-PAH and HIV/Po-PAH) have a better haemodynamic profile than patients with HIV-PAH, specifically, lower pulmonary vascular resistance [6.2 (4.9-8.8) and 7.0 (5.5-11.2) WU vs 8.9 (7.5-12.2) WU] and higher cardiac index [3.1 (2.6-3.8) and 3.0 (2.7-3.7) l/min/m2 vs 2.6 (2.2-2.9) l/min/m2] and mixed venous oxygen saturation [70 (65-75) and 67 (62-71) % vs 61 (55-66)%] values. Despite these differences, the survival of the three groups of patients was not statistically different (5-year survival of patients with Po-PAH was 41%;of patients with HIV/Po-PAH was 46%; and of patients with HIV-PAH was 51%; log-rank test p-value= 0.059) and the prognostic factors that emerge at the multivariate analysis are only parameters associated with the underlying disease. In particular, the parameters independently associated with prognosis are, in patients with Po-PAH, only the CTP score [HR 1.665 (CI 1.153-2.403), p= 0.007]; in patients with HIV-PAH only the treatment with HAART [HR 0.283 (CI 0.119-0.675), p= 0.004]; in patients with HIV/Po-PAH both MELD-Na+ [HR 1.224 (CI 1.064-1.408), p= 0.005] and trans-hepatic venous gradient [HR 1.125 (CI 1.026-1.235), p= 0.013].

Conclusions

in patients with Po-PAH, HIV-PAH, and HIV/Po-PAH adequately treated with PAH medications, the prognosis seems to be related to the underlying disease. This may explain why their survival is not statistically different despite significant demographic, exercise and hemodynamic differences.

111 POST-OPERATIVE OUTCOME OF ADULT PATIENTS WITH PRE-TRICUSPID SHUNT UNDERGOING DEFECT CLOSURE

Background

patients with pulmonary arterial hypertension (PAH) associated with corrected congenital heart disease (CHD) have a worse prognosis than other 3 groups of patients with PAH associated with CHD (Eisenmenger, small defect, prevalent systemic-to-pulmonary shunt). For this reason, in CHD the indication and timing of defect repair should be evaluated carefully. Current recommendations rely essentially on pulmonary vascular resistance (PVR) when deciding about defect closure, but this may be insufficient as PAH may develop even in cases of normal pre-operative PVR. In particular, patients with PVR below 3 WU are usually deemed operable and patients between 3 and 5 WU (gray zone) are deemed operable in case of significant persistence of left-to-right shunt. Detecting preoperative characteristics of patients who developed PAH after pre-tricuspid shunt repair can be helpful when deciding about CHD correction.

Methods

we enrolled adult patients referred to our centre for the suspicious of PAH after pre-tricuspid shunt correction from 2006 to 2021. We evaluated clinical, echocardiographic and hemodynamic parameters before and after defect repair (a post-correction hemodynamic evaluation was performed only in case of non-invasive signs of PAH) and PAH after defect closure was defined by the concomitant occurrence of a mean pulmonary artery pressure (mPAP) >25 mmHg and PVR >3 WU. Continuous variables were summarized using mean and standard deviation and Student's t-test was used for comparisons.

Results

sixty patients were included in the final analysis. After shunt repair, 10 patients (16.6%) were diagnosed with PAH during the long-term follow-up, with no differences given by the type of defect or type of correction. As expected, these patients already had an abnormal baseline hemodynamic profile: 7 had a clear PAH diagnosis before the correction [mPAP >25 mmHg with PVR between 3 and 5 WU and with a pulmonary/systemic cardiac output ratio of at least 1.5] while 3 had pulmonary hypertension related to high pulmonary blood flow (mPAP >25 mmHg and PVR <3 WU). At the baseline hemodynamic evaluation, patients with PAH after shunt repair had higher mPAP (39±6 vs 24±10 mmHg, p <0.001) and PVR (3.7±1.2 vs 1.5±0.9, p <0.001) and lower mixed venous oxygen saturation (81±3 vs 87±3, p <0.001). At the baseline echocardiographic evaluation, patients with PAH after shunt repair had a greater right ventricular hypertrophy (RV wall thickness 0.7±0.1 vs 0.5±0.2 cm, p= 0.011), tricuspid regurgitation jet velocity (424±63 vs 319±62 cm/s, p <0.001) and a significant lower RV fractional area change (34±8 vs 43±9%, p= 0.009).

Conclusions

currently there are no established evidence-based algorithms to predict the development of PAH after defect correction. Our study shows that this condition may persist or develop even when PVR values are lower than 5 WU despite a significant left-to-right shunt before defect closure. Patients with grey zone PVR values require a global clinical, instrumental and hemodynamic assessment that takes into account more than bare calculated PVR that, especially in patients with a high pulmonary blood flow, can be less reliable.

117 PROGNOSTIC VALUE OF ELECTROCARDIOGRAPHIC PARAMETERS IN PATIENTS WITH IDIOPATHIC/HERITABLE/DRUG-INDUCED PULMONARY ARTERIAL HYPERTENSION

Background

despite therapeutic improvement, pulmonary arterial hypertension (PAH) is still a chronic, incurable, high mortality disease. Several clinical, laboratory, hemodynamic and instrumental prognostic factors have been already established in PAH patients. However, no electrocardiographic prognostic factors have been identified so far in a systematic multivariate analysis together with clinical, exercise and haemodynamic parameters.

Methods

patients with idiopathic/heritable/drug-induced PAH (I/H/D-PAH) referred to a single centre were included from 1993 to 2021. All patients underwent baseline clinical, 12-lead ECG, hemodynamic with vasoreactivity test, 6 minutes walking distance (6MWD), brain natriuretic peptide (BNP) or N-terminal pro-BNP (NT-proBNP), WHO functional class evaluation and risk stratification (according to a recently validated simplified version of 2015 ESC/ERS guidelines’ risk table). All cause mortality has been considered to identify the predictors of mortality using univariate and multivariate Cox regression analysis.

Results

570 PAH patients were included: 448 idiopathic (79%), 105 heritable (18%) and 17 drug-induced (3.0%). 20 patients were on atrial flutter/fibrillation at baseline. Considering only electrocardiographic parameters the variables independently associated with prognosis are shown in the table below:

Taking into account also the risk stratification the independent prognostic variables are:

Considering also clinical, exercise and haemodynamic variables the independent prognostic variables are:

Conclusions

in patients with I/H/D-PAH heart rate is a prognostic factor independently from other electrocardiographic, clinical, exercise and haemodynamic parameters as reflects the attempt to preserve the cardiac output in patients with an increased right ventricular afterload causing a reduced stroke volume; both PR interval prolongation, marker of right atrial overload, and QTc prolongation, marker of right ventricle's electrical remodeling, are prognostic variables independently from baseline patient's risk level; right bundle branch block, expression of right ventricular electrical remodeling, has proved to be an independent predictor of mortality merely if we consider only the electrocardiographic parameters.

46 A clinical and echocardiographic score to differentiate pulmonary hypertension due to heart failure with preserved ejection fraction from idiopathic pulmonary hypertension: the PH-HFpEF score

Aims

One of the most challenging differential diagnoses in pulmonary hypertension clinical practice, is the discrimination between idiopathic pulmonary arterial hypertension (IPAH) and pulmonary hypertension due to heart failure with preserved ejection fraction (PH-HFpEF).

We elaborate a score (considering patient clinical history, demographics, and echocardiographic characteristics) that can predict, noninvasively, PH-HFpEF vs. IPAH diagnosis.

Methods and results

Data were prospectively collected on 466 consecutive patients with a final diagnosis of IPAH or PH-HFpEF referred to a single tertiary pulmonary vascular disease centre. Data included clinical history, demographics, and parameters of an electrocardiogram and a transthoracic echocardiogram. A multivariate regression model was developed to predict a PH-HFpEF diagnosis, and an integer risk score was generated using adjusted regression coefficients of the multivariate logistic regression analysis. At the multivariate logistic regression a high ratio between left and right ventricular dimensions, a history of atrial fibrillation (AF), a high body mass index (BMI), a reduced mitral deceleration time and a high E-wave at trans-mitral Doppler, an advanced age and a high right ventricular fractional area change (FAC) were predictors of PH-HFpEF. The derived PH-HFPEF score (Figure), with a cut-point ≥11, yielded a specificity/sensitivity, respectively, for the diagnosis of PH-HFpEF, of 100%/49% with an AUC of 0.987.

Conclusions

The PH-HFPEF score can predict PH-HFpEF vs. IPAH. The PH-HFPEF score may be used to potentially avoid an invasive diagnostic testing in almost half of PH-HFpEF patients.

45 Experience of 5 years of balloon pulmonary angioplasty in a single centre: safety and short-term results

Aims

Balloon pulmonary angioplasty (BPA) has recently been developed as a treatment strategy for chronic thromboembolic pulmonary hypertension (CTEPH) but efficacy and technical safety have to be established. We examine the effects of BPA on patients with inoperable disease or residual pulmonary hypertension (PH) after pulmonary endarterectomy (PEA).

Methods and results

From 2015 to 2020 we enrolled symptomatic inoperable CTEPH patients and patients with residual PH after PEA. At baseline and 3 months after last BPA session patients underwent clinical evaluation, 6-min walking distance (6MWD), and right heart catheterization. Friedman test with Bonferroni post-hoc pairwise analysis was used. Fifty patients [male 42%, median age 68 (51–74) years, 42 inoperable, and 8 with residual PH after PEA] were treated for a total of 156 sessions (median 2 sessions/patient); during each session we treated 2.3 (2.2–2.7) vessels. Results are shown in the Table. Forty-nine patients were treated with medical therapy before BPA (19 with combination therapy). Five pulmonary artery dissection and two haemoptysis with clinical impairment were documented during the procedures; 37 patients had lung injury (radiographic opacity with/without haemoptysis and/or hypoxaemia), none had renal dysfunction, 7 patients had access site complications. Seven patients died during follow-up (none within 30 days from the procedure) because of sepsis (1), heart failure (1), cancer (2), arrhythmic storm (2), and sudden death in patients with severe coronary atherosclerosis (1).

Conclusions

BPA is a safe and effective treatment able to improve symptoms and haemodynamic profile. 45 Table 16MWD, six minute walking distanceCI, cardiac index; mPAP, mean pulmonary arterial pressure; PAC, pulmonary arterial compliance; PVR, pulmonary vascular resistance; RAP, right atrial pressure; SvO2, mixed venous oxygen saturation; WHO-FC, World Health Organization functional class.

Echocardiographic predictors of low risk haemodynamic parameters in patients with pulmonary arterial hypertension

Background

A periodic and multiparametric assessment of the risk profile of patients with pulmonary arterial hypertension (PAH) is essential for a low-risk oriented treatment strategy. Haemodynamic parameters anyway cannot be collected at each scheduled outpatients clinic follow-up visit.

Purpose

To evaluate echocardiographic predictors of haemodynamic low-risk parameters in patients with PAH.

Methods

Patients with PAH referred to our centre were included up to 31 December 2019. All patients underwent baseline demographic, clinical, WHO functional class, 6-minute walk test, brain natriuretic peptide (BNP), right cardiac catheterization and echocardiographic evaluation. Through a multivariate logistic regression analysis we evaluate the echocardiographic predictors of low risk for: 1) BNP/right atrial pressure (RAP): NT-proBNP <300 ng/l/BNP <50 ng/l AND RAP <8 mmHg; 2) cardiac index (CI)/mixed venous oxygen saturation (SvO2): CI ≥2.5 l/min/m2 AND SvO2 >65%. Echocardiographic parameters cut-offs were chosen on the basis of the ROC curves or Literature data.

Results

1020 patients were included. The two analysis were performed independently.

1. Independent echocardiographic predictors of low-risk BNP/RAP were: indexed right atrial area, mitral E/A ratio, dimension and inspiratory collapse of inferior vena cava and indexed left ventricular diastolic volume. We elaborated a score utilizing these parameter cut-offs: an indexed right atrial area of 10.4–15 cm2/m2, a mitral E/A ratio of 0.8, dimension and inspiratory collapse of inferior vena cava indicative of 0–5 vs 5–10 vs 10–20 mmHg and an indexed left ventricular diastolic volume of 32 ml/m2. The score has AUC: 0.62, specificity: 92%, sensitivity: 33%, negative predictive value: 70%, positive predictive value: 69%.

2. Independent echocardiographic predictors of low-risk CI/SvO2 were: S wave at TDI, Tei index, tricuspid annular plane systolic excursion (TAPSE), indexed left ventricular diastolic volume and the severity of the tricuspid regurgitation. We elaborated a score utilizing these parameter cut-offs: an S wave at TDI of 9.5 cm/s, a Tei index of 0.4, a TAPSE of 1.7 cm, an indexed left ventricular diastolic volume of 32 ml/m2 and a mild vs more than mild tricuspid regurgitation. The score has AUC: 0.70, specificity: 89%, sensitivity: 50%, negative predictive value: 71%, positive predictive value: 77%.

Conclusion

Echocardiographic parameters can be used to rule out the presence of low-risk BNP/RAP values (indexed right atrial area, mitral E/A ratio, dimension and inspiratory collapse of inferior vena cava and indexed left ventricular diastolic volume) and low-risk CI/SvO2 (S wave at TDI, Tei index, TAPSE, indexed left ventricular diastolic volume and severity of tricuspid regurgitation).

Funding Acknowledgement

Type of funding sources: None.

Survival of patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension listed for lung transplantation

Background

Lung transplantation (LT) still remains a treatment option for patients with pulmonary arterial hypertension (PAH) and not operable chronic thromboembolic pulmonary hypertension patients (CTEPH).

Purpose

The study is intended to compare the survival of transplant recipients (TR) and the survival of not-transplanted (NT) patients since listing.

Methods

We included all patients with PAH and not-operable CTEPH listed for LT. The survival of NT, TR and of all listed patients was evaluated starting from the date of listing (patients were censored as alive at the time of LT). The survival of TR was also evaluated starting from the date of the LT.

Results

125 patients were included (112, 90% had PAH). Fifty-eight (46%) patients were transplanted, after a mean waiting time of 1.5±1.3 years. Forty-one patients (33%) died while on the list and 25 (20%) patients were alive on the list on December 2019. The survival of NT patients at 1, 3 and 5 years after listing was 74%, 42%, 33%, respectively. The survival of TR patients at 1, 3 and 5 years after listing was 90%, 70%, 63%, respectively. The survival of all patients since listing (intention to treat analysis) at 1, 3 and 5 years was 85%, 59%, 48% respectively. The survival of TR at 1, 3 and 5 years since transplantation was 63%, 61%, 59%, respectively.

Conclusions

Despite biases in the comparison of non-randomized groups, the data confirm a better long-term survival since listing of TR as compared with NT PAH or not-operable CTEPH patients.

Funding Acknowledgement

Type of funding sources: None.

Role of cardiac magnetic resonance in stratifying the prognosis of patients with pulmonary arterial hypertension

Background

Pulmonary arterial hypertension (PAH) is a rare disease characterized by a complex remodeling of heart structures. Cardiac magnetic resonance (CMR) is the gold standard for a non-invasive evaluation of right ventricle (RV) volumes and mass.

Purpose

To define the relationship between clinical, functional, biochemical, haemodynamic and CMR parameters and survival in patients with PAH.

Methods

Consecutive patients with PAH referred to our centre underwent clinical, functional, brain natriuretic peptide (BNP) plasma levels, haemodynamic and CMR evaluation. All patients were treated according to current guidelines. Univariate Cox analysis for survival was performed. Parameters with a p-value <0.1 at the univariate analysis were included in the multivariate analysis.

Results

One hundred forty-seven patients with PAH (mean age 49±17 years, 69% female) were included in the study. Etiology of PAH was: idiopathic/heritable (49%), associated with connective tissue disease (19%), congenital heart disease (12%), portal hypertension/HIV infection (12%) and pulmonary veno-occlusive disease (8%). Thirty-six patients died during follow-up. Parameters significantly associated with mortality at the univariate analysis were age [Hazard Ratio (95% Confidence Interval): 1.043 (1.020–1.067); p<0.001], six-minute walk test (6MWT) [HR: 0.995 (0.993–0.998); p<0.001], WHO-functional class [HR: 2.489 (1.025–6.041); p=0.044], idiopathic-heritable-congenital heart disease aetiology [HR: 0.182 (0.085–0.389); p<0.001], connective tissue disease aetiology [HR: 2.274 (1.099–4.704); p=0.027], pulmonary veno-occlusive disease aetiology [HR: 5.864 (2.328–14.773); p<0.001], right atrial pressure [HR: 1.098 (1.032–1.169); p=0.003], pulmonary artery oxygen saturation [HR: 0.947 (0.921–0.975); p<0.001], BNP levels [HR: 2.214 (1.213–4.039); p=0.010], RV wall thickness [HR: 0.633 (0.399–1.006); p=0.053], RV end diastolic volume [HR: 1.012 (1.003–1.021); p=0.007], RV end systolic volume [HR: 1.014 (1.003–1.024); p=0.011]. Parameters independently associated with mortality at the multivariate analysis were age [HR: 1.035 (1.006–1.064); p=0.018], idiopathic-heritable-congenital heart disease aetiology [HR: 0.355 (0.146–0.860); p=0.022], pulmonary veno-occlusive disease aetiology [HR: 3.129 (1.071–9.143); p=0.037], pulmonary artery oxygen saturation [HR: 0.953 (0.919–0.989); p=0.011], RV wall thickness [HR: 0.527 (0.300–0.927); p=0.026], RV end systolic volume [HR: 1.016 (1.003–1.029); p=0.014].

Conclusion

RV wall thickness and RV end-systolic volume are associated with prognosis in patients with PAH independently from clinical and haemodynamic characteristics. These parameters may be used in the overall risk stratification of PAH patients.

Funding Acknowledgement

Type of funding sources: None.

A pragmatic approach to risk assessment in pulmonary arterial hypertension using the 2015 European Society of Cardiology/European Respiratory Society guidelines

OBJECTIVE

To optimise treatment of patients with pulmonary arterial hypertension (PAH), the 2015 European Society of Cardiology/European Respiratory Society guidelines recommend using risk stratification, with the aim of patients achieving low-risk status. Previous analyses of registries made progress in using risk stratification approaches, however, the focus is often on patients with a low-risk prognosis, whereas most PAH patients are in intermediate-risk or high-risk categories. Using only six parameters with high prognostic relevance, we aimed to demonstrate a pragmatic approach to individual patient risk assessment to discriminate between patients at low risk, intermediate risk and high risk of death.

METHODS

Risk assessment was performed combining six parameters in four criteria: (1) WHO functional class, (2) 6 min walk distance, (3) N-terminal pro-brain natriuretic peptide (BNP)/BNP plasma levels or right atrial pressure and (4) cardiac index or mixed venous oxygen saturation. Assessments were made at baseline and at first follow-up after 3-4 months.

RESULTS

725 PAH treatment-naive patients were analysed. Survival estimates between risk groups were statistically significant at baseline and first follow-up (p<0.001), even when the analysis was performed within PAH etiological subgroups. Similar results were observed in 208 previously treated PAH patients. Furthermore, patients who remained at or improved to low risk had a significantly better estimated survival compared with patients who remained at or worsened to intermediate risk or high risk (p≤0.005).

CONCLUSION

The simplified risk-assessment method can discriminate idiopathic, connective-tissue-disease-associated and congenital-heart-disease-associated PAH patients into meaningful high-risk, intermediate-risk and low-risk groups at baseline and first follow-up. This pragmatic approach reinforces targeting a low-risk profile for PAH patients.

Prognostic role of comorbidities in patients with pulmonary arterial hypertension

Background

Epidemiology of pulmonary arterial hypertension (PAH) is changing and the age at diagnosis and the prevalence of comorbidities are increasing but their prognostic relevance is substantially undefined.

Purpose

To evaluate the prognostic value of comorbidities in patients with PAH and in the different clinical subgroups.

Methods

All patients with PAH referred to a single centre underwent baseline right heart catheterization, brain natriuretic peptide (BNP) plasma levels, 6-min walking distance (6MWD), WHO functional class and anamnestic comorbidities evaluation. Cox regression model was used for analysis (p-value &lt;0.1 was considered for inclusion in multivariate analysis).

Results

1311 patients were included [age 51 years; aetiology: 522 idiopathic/heritable/drug-induced (I/H/D)-PAH, 258 connective tissue disease (CTD)-associated PAH, 242 congenital heart disease (CHD)-associated PAH, 196 portal hypertension/HIV (PoHIV)-associated PAH and 93 pulmonary veno-occlusive disease (PVOD)]. 5% of patients have no comorbidities. At multivariate analysis comorbidities independently associated with prognosis are: systemic hypertension in I/H/D [HR 0.616, p=0.030], mean systemic blood pressure in CTD [HR 0.980, p=0.002] and PVOD [HR 0.962, p=0.006], dyslipidemia in CTD [HR 0.447, p=0.001] and PoHIV [HR 0.201, p=0.026], estimated glomerular filtration rate in PoHIV [HR 1.000, p&lt;0.001] and body mass index (BMI) [HR 0.966, p=0.069] in CTD. In CHD comorbidities are not independent determinants of prognosis. Other variables independently predictive of a worse prognosis are: advanced age in all PAH subgroups except PVOD; male gender in I/H/D; reduced 6MWD in I/H/D, CTD and PVOD; high BNP in I/H/D, CHD and PVOD; low cardiac index in CTD, high right atrial pressure in I/H/D and low mixed venous oxygen saturation in CHD.

Conclusion

The age at PAH diagnosis and the prevalence of comorbidities are increasing but their prognostic role seems of poor relevance as we found a protective role of these variables: high systemic blood pressure (maybe indicative of a better haemodynamic stability) in I/H/D, CTD and PVOD; dyslipidemia and high BMI (maybe indicative of a better nutritional status and a less severe autoimmune disease) in CTD; dyslipidemia and a high glomerular filtration rate (both indicative of a less severe liver disease) in PoHIV.

Funding Acknowledgement

Type of funding source: None

Short term effect of Selexipag in comparison to parenteral prostacyclin analogues in pulmonary arterial hypertension patients started on double-combination therapy with ERA and PDE-5 inhibitors

Background

The event-driven, phase 3, randomized, double-blind, placebo-controlled GRIPHON trial demonstrated that Selexipag reduces the risk of a composite end point of death or morbidity events in patients with pulmonary arterial hypertension (PAH). Despite the advantage of a per os formulation, its efficacy in comparison to parenteral prostacyclin analogues in patients already on oral double-combination therapy with endothelin receptor antagonist (ERA) and phosphodiesterase-5 inhibitor (PDE5-I) is not known.

Purpose

The aim of this study was to compare the effects of Selexipag (S) vs subcutaneous Treprostinil (T) vs intravenous Epoprostenol (E) in PAH patients initially started with double-combination therapy with ERA and PDE5-I.

Methods

We enrolled patients on double combination therapy with ERA + PDE5-I starting S, T or E. Drugs were gradually uptitrated to the maximum tolerated/approved dose. All patients were systematically assessed with WHO-functional class (FC), six minute walk test (6MWT) and right heart catheterization before treatment and 3 months after reaching a stable dose of the drug. Baseline characteristics and changes in 6MWT and haemodynamic parameters were analyzed using Wilcoxon signed-rank test and compared between the 3 drugs with Kruskal-Wallis test.

Results

One hundred and seventy-one patients with PAH were enrolled. Results are shown in the Table. Patients with a complete re-evaluation were 61% of S, 85% of T, 79% with E.

Conclusions

S was prescribed to the oldest and least severe PAH patients. E was prescribed to the youngest and most severe PAH patients and led to the strongest improvement of exercise capacity and haemodynamic profile. T has intermediate characteristics.

Table 1

Funding Acknowledgement

Type of funding source: None

Additional role of echocardiogram in pulmonary arterial hypertension risk stratification according to current ESC/ERS guidelines

Background

Current pulmonary hypertension (PH) guidelines stratify the risk of patients with pulmonary arterial hypertension (PAH) using a multiparametric approach. A simplified risk table has been recently proposed and validated without including echocardiographic parameters.

Purpose

We evaluate the additional role of echocardiogram in PAH risk stratification using the recently proposed simplified risk table in patients with idiopathic/heritable (I/H) PAH and PAH associated with connective tissue disease (CTD) and congenital heart disease (CHD).

Methods

All patients with I/H-PAH, CTD-PAH and CHD-PAH referred to a single centre were included from 2003 to 2017. All patients were treated according to PH guidelines. The simplified risk assessment considered the following criteria: WHO functional class, 6-min walking distance, right atrial (RA) pressure or brain natriuretic peptide (BNP) plasma levels and cardiac index (CI) or mixed venous oxygen saturation (SvO2). For the last 2 criteria the worst parameter was chosen. Risk strata were defined as: Low risk= at least 3 low risk and no high-risk criteria; High risk= at least 2 high risk criteria including CI or SvO2; Intermediate risk= definitions of low or high risk not fulfilled. Then we performed a Cox analysis to evaluate the independent echocardiographic predictors of survival that were subsequently added to the simplified risk table to test their additional role in ameliorating risk stratification.

Results

461 treatment-naïve patients were enrolled. Echocardiographic independent predictors of prognosis were the severity of tricuspid regurgitation [HR (95% CI) = 1.013 (1.006–1.021); p-value = 0.001], right atrial area [HR (95% CI) = 1.028 (1.012–1.045); p-value = 0.001] and the presence of pericardial effusion [HR (95% CI) = 1.533 (1.142–2.057); p-value= 0.004]. Only RA area significantly ameliorate the risk stratification power of the recently validated simplified PAH risk table (likelihood ratio chi2 increased from 63.8 to 68.1, likelihood ratio test = 0.039). Due to the significant correlation between RA area and both RA pressure (r=0.470; p&lt;0.001) and BNP (r=0.372; p=0.004), we elaborate a second risk table in which RA area (utilizing the cut-offs proposed by the current PH guidelines) was considered together within the criteria including RA pressure and BNP (the worst parameter of the 3 was considered). Considering the second risk table including RA area the risk stratification power significantly improved (likelihood ratio chi2 increased from 63.8 to 72.7, AIC/BIC decreased from 1956/1964 to 1947/1955).

Conclusions

Echocardiographic RA area significantly improve the risk discrimination power of the recently proposed simplified risk table for patients with PAH.

Funding Acknowledgement

Type of funding source: None

P4688Additional role of unmodifiable risk factors in pulmonary arterial hypertension risk stratification according to current ESC/ERS guidelines

Background

Current pulmonary hypertension (PH) guidelines stratify the risk of patients with pulmonary arterial hypertension (PAH) using a multiparametric approach. Anyway, the role of unmodifiable risk factors is not taken into account.

Purpose

The aim of this study was to evaluate the role of unmodifiable risk factors (age, gender, PAH aetiology) in PAH risk stratification using the recently proposed simplified risk table and to test if these factors influence the response to PAH-specific treatment.

Methods

All patients with PAH referred to a single centre were included from 2003 to 2017. We applied a simplified risk assessment strategy using the following criteria: WHO functional class, 6-min walking distance, right atrial pressure or brain natriuretic peptide plasma levels and cardiac index (CI) or mixed venous oxygen saturation (SvO2). The last 2 criteria were based on which parameter was available; if both were available the worst was chosen. Risk strata were defined as: Low risk= at least 3 low risk and no high-risk criteria; High risk= at least 2 high risk criteria including CI or SvO2; Intermediate risk= definitions of low or high risk not fulfilled. Then we performed multivariate Cox analysis to evaluate what are the independent predictors of survival (age, gender, PAH aetiology together with the recently proposed simplified PAH risk table) and we tested if these factors influence the response to PAH specific therapy comparing the % improvement of hemodynamic parameters from baseline to 3–4 months after starting treatment. Wilcoxon-Mann-Whitney test was used for comparisons.

Results

Six hundreds and twenty-one treatment-naïve patients were enrolled. Age [HR (95% CI) = 1.022 (1.014–1.030); p-value <0.001], male gender [HR (95% CI) = 1.881 (1.479–2.392); p-value <0.001] and connective tissue disease (CTD)-PAH aetiology [HR (95% CI)= 2.278 (1.733–2.995); p-value <0.001] were all independent predictors of prognosis in patients with PAH together with the recently validated simplified PAH risk table [HR (95% CI) = 2.161 (1.783–2.618); p-value <0.001] but they didn't significantly influence the response to PAH specific treatment as shown in the Figure.

Figure 1

Conclusions

Age, gender and CTD-PAH aetiology significantly influence prognosis together with the recently validated simplified PAH risk table but don't significantly influence the response to PAH-specific treatment.

Acknowledgement/Funding

None

P4676Experience of three years of balloon pulmonary angioplasty in a single centre: safety and short term results

Background

Balloon pulmonary angioplasty (BPA) has recently been developed as an alternative and less-invasive treatment strategy for chronic thromboembolic pulmonary hypertension (CTEPH) but therapeutic efficacy and technical safety of the technique have to be established.

Purpose

To examine the effects of BPA on patients with inoperable disease or residual pulmonary hypertension (PH) after pulmonary endarterectomy (PEA).

Methods

From June 2015 to January 2019 we enrolled symptomatic (WHO-FC ≥II) inoperable CTEPH patients and patients with residual PH after PEA. At baseline and after 3 months after last BPA session all patients underwent clinical evaluation, six-minute walking distance (6MWD) and right heart catheterization. For comparisons Friedman test (with Bonferroni post-hoc pairwise analysis) was used.

Results

Forty-one patients [male 49%, median age 65 (52–75) years, 34 inoperable and 7 with residual PH after PEA] were treated for a total of 111 sessions (median number of sessions for each patient: 2); during each session we treated 2 (2.0–2.5) vessels. Results are shown in the Table. Forty patients were treated with medical therapy before BPA (16 with combination therapy). Four pulmonary artery dissection and 2 haemoptysis with clinical impairment were documented during the procedures; 27 patients had lung injury (radiographic opacity with/without hemoptysis and/or hypoxemia), none had renal dysfunction, 6 patients had access site complications. Five patients died during follow-up (none within 30 days from the procedure) because of sepsis (1), heart failure (1), cancer (1), arrhythmic storm (1) and sudden death in a patients with severe coronary atherosclerosis (1).

Table 1 Median (interquartile range) Baseline Baseline ÷ Pre-BPA Pre-BPA Pre-BPA ÷ Post-BPA Post-BPA Global (n=41) 8 (3–49) months (n=41) 10 (6–18) months (n=32) p-value WHO-FC III-IV (%) 88 N.S. 83 <0.05 42 <0.001 6MWD (m) 430 (346–560) N.S. 425 (357–500) <0.05 450 (375–605) <0.001 RAP (mmHg) 6 (5–8) N.S. 6 (5–8) N.S. 6 (4–8) 0.023 mPAP (mmHg) 46 (40–52) <0.05 43 (33–50) <0.05 36 (28–41) <0.001 CI (l/min/m2) 2.6 (2.2–3.0) N.S. 2.7 (2.2–3.0) <0.05 3.1 (2.6–3.5) 0.004 PVR (WU) 7.5 (5.6–11.5) <0.05 6.5 (4.7–10.3) <0.05 4.1 (3.3–5.9) <0.001 PA O2 Sat (%) 69 (63–71) N.S. 69 (63–72) N.S. 69 (63–73) 0.002 CI, Cardiac Index; mPAP, mean Pulmonary Arterial Pressure; PVR, Pulmonary Vascular Resistance; PA O2 Sat, Pulmonary Artery Oxygen Saturation; RAP, Right Atrial Pressure; 6MWD, 6 Minute Walking Distance; WHO-FC, World Health Organization Functional Class.

Conclusions

BPA is a safe and effective treatment able to improve symptoms and hemodynamic profile in inoperable CTEPH patients and in patients with residual PH after PEA.

Acknowledgement/Funding

None

P4680Prognostic value of stroke volume index in patients with pulmonary arterial hypertension at intermediate risk

Background

Current pulmonary hypertension (PH) guidelines stratify the risk of patients with pulmonary arterial hypertension (PAH) using a multiparametric approach. Low, intermediate and high-risk are defined by estimated 1-year mortality of <5%, 5–10% and >10%, respectively. This risk assessment has been recently validated in 3 cohorts of PAH patients and a simplified risk table for patients with idiopathic/heritable (I/H) PAH and PAH associated with connective tissue disease (CTD) and congenital heart disease (CHD) has been recently proposed and validated. However, with this method most of the patients are classified in the intermediate risk category and additional strategies are required to further stratify this group of PAH patients.

Purpose

To evaluate the prognostic value of SVI measured with right heart catheterization (RHC) in patients at intermediate-risk.

Methods

All treatment naïve patients with I/H-PAH, CTD-PAH and CHD-PAH referred to a single centre were included from 2003 to 2017. All patients were assessed at baseline and at the 1st follow-up at 3–4 months after starting PAH-specific therapy (1st F-UP) with RHC, brain natriuretic peptide (BNP) plasma levels, 6-min walking distance (6MWD) and WHO functional class. We applied a simplified risk assessment strategy using the following criteria: WHO functional class, 6MWD, right atrial pressure or BNP plasma levels and cardiac index (CI) or mixed venous oxygen saturation (SvO2). The last 2 criteria were based on which parameter was available; if both were available the worst was chosen. Risk strata were defined as: Low risk= at least 3 low risk and no high-risk criteria; High risk= at least 2 high risk criteria including CI or SvO2; Intermediate risk= definitions of low or high risk not fulfilled. The prognostic value of SVI was assessed using Cox regression analysis. Intermediate risk patients were further stratified in intermediate-low and intermediate-high risk taking into account the value of SVI that best discriminate prognosis (according to ROC curve analysis). Kaplan Meier curves and Log-rank test were used for survival analysis.

Results

Seven hundreds and twenty-five patients were enrolled. SVI is able to stratify the prognosis of PAH patients at 1st F-UP [HR 0.979 (0.964–0.994), p-value= 0.008] but not at baseline [HR 0.986 (0.970–1.002), p-value= 0.085]. The best predictive cut-off value is 38 ml/m2 (AUC= 0.66, sensitivity= 73%, specificity= 59%). Survival curves are shown in the Figure.

Figure 1

Conclusions

SVI assessed at 1st F-UP is predictive of prognosis and the cut off value of 38 ml/m2 is able to further stratify the survival of intermediate risk PAH patients.

Acknowledgement/Funding

None

Coagulation and Fibrinolysis Study in Systemic Lupus erythematosus: Haematological, Urinary and Tissue Parameters

Haematochemical, urinary and tissue parameters were examined in the elaboration of the coagulation and fibrinolysis profile in 33 cases of systemic lupus erythematosus in different stages of the disease. Coagulation abnormalities varied from hypo- to hyper-coagulabitity, these being often associated in the same patient, either simultaneously or at different stages of the disease. Activation of coagulation, closely related to the immunological activity of the disease, was present in 80% cases in the acute stage, and 36% of those in the remission stage. The lupus-like anticoagulant was not much involved, and platelets were the prime figures in the haemostatic abnormalities of lupus, those being the preferred target of direct antibody activities, or possibly of immune complexes as well. Activation of the coagulatory cascade is not uncommonly accompanied by a thrombophilic tendency coupled with signs of consumption, this being the expression of a continuously stimulated haemostatic balance.

Memory effects in nematics with quenched disorder

We present a combined experimental and Monte Carlo study of a nematic phase in the presence of quenched disorder. The turbidity of a nematic liquid crystal embedded in a porous polymer membrane is measured under different applied field conditions for field-cooled and zero-field-cooled samples. We find that a significant permanent alignment of the nematic can be induced by fields as low as 0.1 V/microm applied during the isotropic to nematic transition. An analogous effect and dependence on sample history is found by studying the order parameter of a sprinkled disorder Lebwohl-Lasher spin model, indicating that dilute quenched randomness is sufficient to produce memory effects in nematics. The large memory induced by field cooling appears to be written in the system during the transition as a result of the field action on freely oriented nematic nuclei. At lower temperature the nuclei consolidate into permanent nematic textures developed from the interaction with quenched disorder.

Nematics with quenched disorder: pinning out the origin of memory

Memory effects and glassy behavior have been repeatedly observed in disordered nematic liquid crystals but the connection between these effects and the system topology remained unrevealed. We present an analysis of the local and global topology of the nematic ordering in the presence of quenched disorder and we show that nematics with quenched disorder can be mapped into a system of pinned defect lines and that the memory of the system stems from the pinning of these strings.

[Analysis of the composition of 2700 urinary calculi examined by infrared spectrophotometry, 1979-1989]

Two thousand seven hundred samples, received as urinary calculi, in a Turin based laboratory, in the period between March 1979 and February 1989, were examined by infrared spectroscopy to identify components even of difficult characterization: a special procedure was used and it is described. Knowing the composition of each calculus, a comparison was made between the incidence of each compound in the first 1500 samples (1979-1984) and in the remaining 1200 ones (1984-1989). Besides an increase in calcium oxalate as main component, a marked reduction in incidence of struvite was found in the calculi belonging to the second period of observation. The possible interference in calculi composition by various therapy for renal infection is discussed.

In vivo localization of C3 on the brush border of proximal tubules of kidneys from nephrotic patients

Deposits of C3 but not of C1q and C4 were detected on the proximal tubules of kidneys from nephrotic patients with non-selective proteinuria. The incidence of tubular C3 deposits was significantly higher in patients with membranous glomerulonephritis, focal glomerulosclerosis, membrano-proliferative glomerulonephritis and non-selective proteinuria than in patients with minimal change disease, nephrotic syndrome and selective proteinuria or in patients with glomerular disease, but without nephrotic syndrome. The occurrence of tubular C3 deposits was positively correlated with the amount of urinary C3 excretion. In vitro studies showed that the human normal kidney as well as pathologic specimens negative for in vivo tubular C3 deposits were able to bind C3 on the brush border of proximal tubules when incubated with fresh heterologous serum. In contrast, in patients with non-selective proteinuria and in vivo tubular C3 deposits, the binding of heterologous C3 to the brush border of proximal tubules was markedly reduced. The positive correlation between the occurrence of tubular C3 deposits and the urinary complement excretion, together with the detection of the C3 breakdown products in the urines further supported the hypothesis that complement components, once filtrated through the glomerular barrier, might be activated by the brush border of the proximal tubule.

In vitro alternative pathway activation of complement by the brush border of proximal tubules of normal rat kidney

The purpose of this study was to investigate which structures of the nephron, if any, are capable of directly activating the complement (C) system. To this end, two sets of experiments were performed. First, activation of C was assessed on sections of frozen kidney tissue, using the indirect immunofluorescence technique for the demonstration of C fixation. Second, glomerular or tubular fractions of kidney were incubated with normal fresh serum, and subsequent C consumption was measured. The data obtained support the interpretation that the brush border of proximal tubules activates the alternative pathway of the C system. This phenomenon may have pathogenic significance in conditions of aselective proteinuria.

In vitro alternative pathway activation of complement by the brush border of proximal tubules of normal rat kidney

The purpose of this study was to investigate which structures of the nephron, if any, are capable of directly activating the complement (C) system. To this end, two sets of experiments were performed. First, activation of C was assessed on sections of frozen kidney tissue, using the indirect immunofluorescence technique for the demonstration of C fixation. Second, glomerular or tubular fractions of kidney were incubated with normal fresh serum, and subsequent C consumption was measured. The data obtained support the interpretation that the brush border of proximal tubules activates the alternative pathway of the C system. This phenomenon may have pathogenic significance in conditions of aselective proteinuria.

Coagulation and fibrinolysis study in systemic lupus erythematosus: haematological, urinary and tissue parameters

Haematochemical, urinary and tissue parameters were examined in the elaboration of the coagulation and fibrinolysis profile in 33 cases of systemic lupus erythematosus in different stages of the disease. Coagulation abnormalities varied from hypo- to hyper-coagulability, these being often associated in the same patient, either simultaneously or at different stages of the disease. Activation of coagulation, closely related to the immunological activity of the disease, was present in 80% cases in the acute stage, and 36% of those in the remission stage. The lupus-like anticoagulant was not much involved, and platelets were the prime figures in the haemostatic abnormalities of lupus, those being the preferred target of direct antibody activities, or possibly of immune complexes as well. Activation of the coagulatory cascade is not uncommonly accompanied by a thrombophilic tendency coupled with signs of consumption, this being the expression of a continuously stimulated haemostatic balance.

[Hormonal modulation of inflammation]

The tissue damage during the inflammation is determined by the enzymes and the mediators of anaphylaxis released from polymorphonuclear cells (PMN), platelets, basophils and mastocytes. The control of this release involves the cAMP and cGMP. The cyclic nucleotides independently or synergically regulate the polymerisation of the microtubules and the microfilaments. Drugs increasing the intracellular concentration of cAMP or cGMP inhibit or enhance respectively the enzymatic release from PMN, basophils and mastocytes. In the platelets, cAMP plays a very important role, whereas the cGMP function is controversial.