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.

Prognostic value of pulmonary artery diameter in patients with pulmonary arterial hypertension

Background

Pulmonary artery (PA) dilation is common in pulmonary arterial hypertension (PAH) and may cause left main coronary artery (LMCA) compression. This complication have been sistematically evaluated in patients with angina but no evidence is available for patients asymptomatic for angina.

Purpose

To evaluate the prognostic value of PA diameter and the prevalence of LMCA compression in PAH patients with and without angina.

Methods

All patients with PAH and a baseline angio-CT scan were included. The last angio-CT scan performed was considered for PA diameter increase velocity calculation. Patients with angina or radiological signs of suspected LMCA compression underwent a coronary (cor)-CT scan. Patients with a not negative cor-CT underwent invasive coronary angiography. If clinically indicated invasive coronary angiography was performed without a preliminary cor-CT. To evaluate the predictivity for compression at coronary angiography the PA diameter at cor-CT or at the nearest angio-CT scan was considered.

Results

958 patients were included. PA diameter at baseline is higher in patients with congenital heart disease (CHD) and is not predictive of death. The velocity of PA diameter increase is lower in patients with connective tissue disease and is a risk factor for death in both overall population and different etiological subgroups except CHD and pulmonary veno-occlusive disease. 180 patients had angina and 50 had LMCA compression. 120 patients without angina underwent cor-CT and/or coronary angiography and 15 patients had LMCA compression. The best PA diameter cut-offs predicting LMCA compression in symptomatic/asymptomatic patients were, respectively, 40/42 mm (sensitivity and specificity, respectively, 80 and 72%/87 and 77%).

Conclusion

28% of patients with angina and 13% of patients without angina had LMCA compression. We found a similar PA diameter predicting LMCA compression in patients with or without angina. PA diameter, instead, was not predictive of prognosis (maybe because most deaths were related to heart failure and also because patients with LMCA compression were treated with stenting, possibly preventing sudden cardiac death). Eventually, PA diameter velocity increase is associated with prognosis but this may only reflect a severe disease refractory to medical therapy.

Funding Acknowledgement

Type of funding source: None

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 <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<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<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