Echocardiographic probability of pulmonary hypertension: a validation study.

BACKGROUND: According to current guidelines, the diagnosis of pulmonary hypertension (PH) relies on echocardiographic probability followed by right heart catheterisation (RHC). How echocardiography predicts PH recently redefined by mean pulmonary arterial pressure (mPAP) >20 mmHg instead of ≥25 mmHg and pulmonary vascular disease defined by pulmonary vascular resistance (PVR) ≥3 or >2 WU has not been established. METHODS: A total of 278 patients referred for PH underwent comprehensive echocardiography followed by RHC. 15 patients (5.4%) were excluded because of insufficient quality echocardiography. RESULTS: With PH defined by mPAP >20 mmHg, 23 patients had no PH, 146 had pre-capillary PH and 94 had post-capillary PH. At univariate analysis, maximum tricuspid regurgitation velocity (TRV) 2.9-3.4 m·s-1, left ventricle (LV) eccentricity index >1.1, right ventricle outflow tract acceleration time (RVOT-AT) <105 ms or notching, RV/LV basal diameter >1 and pulmonary artery diameter predicted PH, whereas inferior vena cava diameter and right atrial area did not. At multivariable analysis, only TRV ≥2.9 m·s-1 independently predicted PH. Additional independent prediction of PVR ≥3 WU was offered by LV eccentricity index >1.1, and RVOT-AT <105 ms and/or notching, but with no improvement of optimal combination of specificity and sensitivity or positive prediction. CONCLUSIONS: Echocardiography as recommended in current guidelines can be used to assess the probability of redefined PH in a referral centre. However, the added value of indirect signs is modest and sufficient quality echocardiographic signals may not be recovered in some patients.

The paradox of pulmonary arterial hypertension in Italy in the COVID-19 era: is risk of disease progression around the corner?

OBJECTIVE: The coronavirus disease 2019 (COVID-19) outbreak has led to significant restrictions on routine medical care. We conducted a multicentre nationwide survey of patients with pulmonary arterial hypertension (PAH) to determine the consequences of governance measures on PAH management and risk of poor outcome in patients with COVID-19. MATERIALS AND METHODS: The present study, which included 25 Italian centres, considered demographic data, the number of in-person visits, 6-min walk and echocardiographic test results, brain natriuretic peptide/N-terminal pro-brain natriuretic peptide test results, World Health Organization functional class assessment, presence of elective and non-elective hospitalisation, need for treatment escalation/initiation, newly diagnosed PAH, incidence of COVID-19 and mortality rates. Data were collected, double-checked and tracked by institutional records between March 1 and May 1, 2020, to coincide with the first peak of COVID-19 and compared with the same time period in 2019. RESULTS: Among 1922 PAH patients, the incidences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and COVID-19 were 1.0% and 0.46%, respectively, with the latter comparable to that in the overall Italian population (0.34%) but associated with 100% mortality. Less systematic activities were converted into more effective remote interfacing between clinicians and PAH patients, resulting in lower rates of hospitalisation (1.2% versus 1.9%) and related death (0.3% versus 0.5%) compared with 2019 (p<0.001). A high level of attention is needed to avoid the potential risk of disease progression related to less aggressive escalation of treatment and the reduction in new PAH diagnoses compared with 2019. CONCLUSION: A cohesive partnership between healthcare providers and regional public health officials is needed to prioritise PAH patients for remote monitoring by dedicated tools.

Risk Reduction and Hemodynamics with Initial Combination Therapy in Pulmonary Arterial Hypertension.

Rationale: An initial oral combination of drugs is being recommended in pulmonary arterial hypertension (PAH), but the effects of this approach on risk reduction and pulmonary vascular resistance (PVR) are not known.Objectives: To test the hypothesis that a low-risk status would be determined by the reduction of PVR in patients with PAH treated upfront with a combination of oral drugs.Methods: The study enrolled 181 treatment-naive patients with PAH (81% idiopathic) with a follow-up right heart catheterization at 6 months (interquartile range, 144-363 d) after the initial combination of endothelin receptor antagonist + phosphodiesterase-5 inhibitor drugs and clinical evaluation and risk assessments by European guidelines and Registry to Evaluate Early and Long-Term PAH Disease Management scores.Measurements and Main Results: Initial combination therapy improved functional class and 6-minute-walk distance and decreased PVR by an average of 35% (median, 40%). One-third of the patients had a decrease in PVR <25%. This poor hemodynamic response was independently predicted by age, male sex, pulmonary artery pressure and cardiac index, and at echocardiography, a right/left ventricular surface area ratio of greater than 1 associated with low tricuspid annular plane systolic excursion of less than 18 mm. A low-risk status at 6 months was achieved or maintained in only 34.8% (Registry to Evaluate Early and Long-Term PAH Disease Management score) to 43.1% (European score) of the patients. Adding criteria of poor hemodynamic response improved prediction of a low-risk status.Conclusions: A majority of patients with PAH still insufficiently improved after 6 months of initial combinations of oral drugs is identifiable at initial evaluation by hemodynamic response criteria added to risk scores.

A multicentric quality-control study of exercise Doppler echocardiography of the right heart and the pulmonary circulation. The RIGHT Heart International NETwork (RIGHT-NET).

PURPOSE: This study was a quality-control study of resting and exercise Doppler echocardiography (EDE) variables measured by 19 echocardiography laboratories with proven experience participating in the RIGHT Heart International NETwork. METHODS: All participating investigators reported the requested variables from ten randomly selected exercise stress tests. Intraclass correlation coefficients (ICC) were calculated to evaluate the inter-observer agreement with the core laboratory. Inter-observer variability of resting and peak exercise tricuspid regurgitation velocity (TRV), right ventricular outflow tract acceleration time (RVOT Act), tricuspid annular plane systolic excursion (TAPSE), tissue Doppler tricuspid lateral annular systolic velocity (S'), right ventricular fractional area change (RV FAC), left ventricular outflow tract velocity time integral (LVOT VTI), mitral inflow pulsed wave Doppler velocity (E), diastolic mitral annular velocity by TDI (e') and left ventricular ejection fraction (LVEF) were measured. RESULTS: The accuracy of 19 investigators for all variables ranged from 99.7 to 100%. ICC was > 0.90 for all observers. Inter-observer variability for resting and exercise variables was for TRV = 3.8 to 2.4%, E = 5.7 to 8.3%, e' = 6 to 6.5%, RVOT Act = 9.7 to 12, LVOT VTI = 7.4 to 9.6%, S' = 2.9 to 2.9% and TAPSE = 5.3 to 8%. Moderate inter-observer variability was found for resting and peak exercise RV FAC (15 to 16%). LVEF revealed lower resting and peak exercise variability of 7.6 and 9%. CONCLUSIONS: When performed in expert centers EDE is a reproducible tool for the assessment of the right heart and the pulmonary circulation.

Invasive and Noninvasive Evaluation for the Diagnosis of Pulmonary Hypertension: How to Use and How to Combine Them.

The etiologic diagnosis of pulmonary hypertension (PH) may be very challenging. Right-heart catheterization (RHC) in isolation cannot classify a precapillary PH patient into group 1, 3, 4, or 5. Moreover, RHC may be not sufficient for reaching a definitive differential diagnosis of precapillary or postcapillary PH if hemodynamic data are not integrated in clinical context and combined with information gleaned from noninvasive imaging. Therefore, only the integration of risk factors, clinical evaluation, invasive and noninvasive tests allows the physician to distinguish between different forms of PH.

Echocardiographic assessment of right ventricular contractile reserve in healthy subjects.

BACKGROUND: Exercise-induced increase in pulmonary artery systolic pressure (PASP) as a possible measure of right ventricular (RV) contractile reserve has been shown to predict survival in severe pulmonary hypertension. However, RV contractile reserve can also be measured by changes in stroke volume (SV), tricuspid annular plane systolic excursion (TAPSE), or tricuspid annular systolic velocity (S'). The limits of normal values and the functional significance of these changes in healthy subjects are not well known. METHODS: In this prospective study, 90 healthy subjects (45 male, mean age 39 ± 13 years) underwent exercise stress echocardiography with measurement of TAPSE, S', TAPSE/PASP, SV, and PASP at rest and peak exercise. Maximum and minimum normal values were reported for all indices. RESULTS: Normal values of exercise-induced changes (Δ) were 4 to 10 mm for TAPSE, 6 to 14 cm/s for S', 12 to 57 mm Hg for PASP, 0 to 96 mL for SV, and -1.2 to 0 mm/mm Hg for TAPSE/PASP. At peak exercise, women showed lower ΔTAPSE/PASP, ΔPASP, ΔS', and ΔSV, but higher TAPSE/PASP than men. Aging was associated with decreased ΔTAPSE/PASP, ΔTAPSE, ΔS', ΔPASP, and ΔSV. In addition, ΔS', ΔTAPSE/PASP, ΔPASP, and ΔSV, but not ΔTAPSE, were directly correlated with maximum workload. CONCLUSIONS: Our results provide age- and sex-related limits of normal for RV contractile reserve as assessed by exercise stress echocardiography and demonstrate that RV systolic function indices (PASP, TAPSE, S', and TAPSE/PASP) correlate with maximum exercise capacity.

Imaging the right heart pulmonary circulation unit: Insights from advanced ultrasound techniques.

The right heart pulmonary circulation unit (RH-PCU) is a key determinant of prognosis in several cardiorespiratory diseases. Although right heart catheterization is considered the gold standard for pulmonary hemodynamic assessment, a comprehensive cardiovascular ultrasound approach is an essential step in the diagnostic-prognostic clinical pathway of patients with suspect or overt pulmonary hypertension. The exponential development of advanced ultrasound techniques (strain, 3-dimensional echocardiography and lung ultrasound) has led to new insights into the evaluation of RH-PCU structure and function, overcoming some limitations of standard Doppler echocardiography. In the near future, exercise Doppler echocardiography may become a useful technique for detecting a latent stage of pulmonary hypertension and for evaluating right ventricular contractile reserve.

Gender-related differences in pulmonary arterial hypertension targeted drugs administration.

During the last 15 years, a real "paradigm-shift" occurred, due to the development of PAH-targeted drugs, leading to crucial improvements in symptoms, exercise capacity, hemodynamics and outcome of PAH patients. In order to describe differences regarding epidemiology and therapy in PAH according to gender, we performed a review of the available literature in "PubMed" and "Web of Science" databases. In order to find relevant articles, we combined each of the following the keywords "pulmonary arterial hypertension", "gender", "sex", "men", "woman", "male", "female", "phosphodiesterase inhibitors", "endothelin receptor antagonists", "prostanoids". While there is a substantial agreement among epidemiological studies in reporting an increased prevalence of pulmonary arterial hypertension (PAH) among women, male PAH patients are affected by a higher impairment of the right ventricular function and consequently experience poorer outcomes. With regards to PAH-targeted drug administration, endothelin receptor antagonists (ERAs) and prostacyclin analogues (PC) show better treatment results in female PAH patients, while phosphodiesterase-5 inhibitors (PD5-I) seem to exert a more beneficial effect on male patients. However, to date no clear consensus could be formed by the available literature, which is constituted mainly by retrospective studies. Females with PAH are more prone to develop PAH, while males experience poorer outcomes. Females PAH might benefit more from ERAs and PC, while males seem to have more beneficial effects from PD5-I administration. However, more research is warranted in order to assess the most effective treatment for PAH patients according to gender.

Pulmonary arterial hypertension: the key role of echocardiography.

Echocardiography is a key screening tool in the diagnostic algorithm of pulmonary arterial hypertension (PAH). It provides an estimate of right ventricular function and pulmonary artery pressure, either at rest or during exercise, and is useful in ruling out secondary causes of pulmonary hypertension (PH) such as left heart disease or congenital heart disease. Several studies have showed that echocardiography is insufficiently precise as single tool for the ultimate diagnosis of PH respect to the right heart catheterization, considered the gold standard technique. Echocardiography is valuable in assessing prognosis and treatment options, monitoring the efficacy of specific therapeutic interventions, and detecting the preclinical stages of disease. The ideal imaging modality for accurate noninvasive assessment of the right heart should be accurate and precise, not influenced by loading conditions, routinely practicable and easily repeatable. For all such reasons and considering that PAH is a rare and severe condition, a complete noninvasive assessment of right heart function requires a deep knowledge of the disease and a multimodality approach.

Gaps in evidence in the management of patients with intermediate-risk pulmonary arterial hypertension: Considerations following the ESC/ERS 2022 guidelines.

A comprehensive evaluation of risk, using multiple indices, is necessary to provide reliable prognostic information and guide therapy in pulmonary arterial hypertension (PAH). The current ESC/ERS guidelines suggest using a three-strata model for incident (newly diagnosed) patients and a four-strata model for prevalent patients with PAH. The four-strata model serves as a fundamental risk-stratification tool and relies on a minimal dataset of indicators that must be considered during follow-up. Nevertheless, there are still areas of vagueness and ambiguity when classifying and managing patients in the intermediate-risk category. For these patients, considerations should include right heart imaging, hemodynamics, as well as individual factors such as age, sex, genetic profile, disease type, comorbidities, and kidney function. The aim of this report is to present case studies, with a specific focus on patients ultimately classified as intermediate risk. We aim to emphasize the challenges and complexities encountered in the realms of diagnosis, classification, and treatment for these particular patients.

Right heart failure as a cause of pulmonary congestion in pulmonary arterial hypertension.

AIMS: Recent studies have shown that lung ultrasound-assessed pulmonary congestion is worse in heart failure when pulmonary vascular resistance (PVR) is increased, suggesting a paradoxical relationship between right heart failure and increased lung water content. Accordingly, we wondered if lung ultrasound would reveal otherwise clinically silent pulmonary congestion in patients with pulmonary arterial hypertension (PAH). METHODS AND RESULTS: All patients referred for suspicion of PAH in a tertiary centre from January 2020 to December 2022 underwent a complete diagnostic work-up including echocardiography, lung ultrasound and right heart catheterization. Pulmonary congestion was identified by lung ultrasound B-lines using an 8-site scan. The study enrolled 102 patients with idiopathic PAH (mean age 53 ± 13 years; 71% female). World Health Organization functional classes I, II, and III were found in 2%, 52%, and 46% of them, respectively. N-terminal pro-brain natriuretic peptide (NT-proBNP) was 377 pg/ml (interquartile range [IQR] 218-906). B-lines were identified in 77 out of 102 patients (75%), with a median of 3 [IQR 1-5]. At univariable analysis, B-lines were positively correlated with male sex, age, NT-proBNP, systolic pulmonary artery pressure (sPAP), right atrial pressure (RAP), PVR, left ventricular end-diastolic volume and tricuspid annular plane systolic excursion (TAPSE), and negatively with cardiac output and stroke volume. At multivariable analysis, RAP (p < 0.001), TAPSE/sPAP (p = 0.001), and NT-proBNP (p = 0.04) were independent predictors of B-lines. CONCLUSION: Lung ultrasound commonly discloses pulmonary congestion in PAH. This finding is related to right ventricular to pulmonary artery uncoupling, and may tentatively be explained by increased central venous pressure impeding lymphatic outflow.

[ANMCO/SIC Consensus statement on pulmonary arterial hypertension]. / Documento di consenso ANMCO/SIC sull'ipertensione arteriosa polmonare.

Pulmonary hypertension (PH) is a frequent pathological condition worldwide, mainly secondary to cardiovascular and respiratory diseases, with a poor prognosis. Pulmonary arterial hypertension (PAH) is a rare form that affects the arterial pulmonary vasculature. PH and PAH are characterized by non-specific symptoms and a progressive increase of pulmonary vascular resistance that results in progressive, sometimes irreversible, right ventricular dysfunction. In recent years, a growing medical and social commitment on this disease allowed more accurate diagnosis in shorter times. However, the gap between guidelines and clinical practice remains a challenge for all medical doctors involved in the disease management. Considering the needs to share and describe diagnostic and therapeutic pathways, to measure the results obtained and to address the economical and organizational problems of this disease, all involved figures should collaborate to improve its prognostic impact and health expenses. In this consensus document, the PH experts of the Italian Association of Hospital Cardiologists (ANMCO) together with those of the Italian Society of Cardiology (SIC), address 1) definition, classification and unmet needs of PH and PAH; 2) classification and characteristics of centers involved in the diagnosis and treatment of the disease; 3) proposal of organization of a diagnostic-therapeutic pathway, based on robust and recent scientific evidence.

Right ventricular phenotyping in incident patients with idiopathic pulmonary arterial hypertension.

BACKGROUND: Right ventricular (RV) imaging has not a definite role in risk stratification of pulmonary arterial hypertension (PAH) patients. We tested the hypothesis that echocardiography-derived phenotypes, depicting different degrees of RV remodeling and dysfunction, may provide additional prognostic information to current risk stratification tools. METHODS: Consecutive incident PAH patients aged ≥18 years, diagnosed between January 2005 and December 2021, underwent clinical assessment, right heart catheterization, standard echocardiography. Simple echocardiographic variables were combined in order to define a priori four phenotypes representing different degrees of RV dilatation and RV-pulmonary arterial (PA) coupling: Phenotype 1 with mildy dilated right ventricle and preserved RV-PA coupling (n = 152 patients); phenotype 2 with mildly dilated right ventricle and poor RV-PA coupling (n = 143 patients); phenotype 3 with severely dilated right ventricle and preserved RV-PA coupling (n = 201 patients); phenotype 4 with severely dilated right ventricle and poor RV-PA coupling, with or without severe tricuspid regurgitation (n = 519 patients). Risk stratification was based on the European Society of Cardiology/European Respiratory Society (ESC/ERS) 3-strata model and Registry to Evaluate Early and Long-Term PAH disease Management (REVEAL) 2.0 score. RESULTS: These phenotypes were present in all risk groups. Notably, regardless of the ESC/ERS risk stratum assigned to the patient, phenotype 4 was associated with a 2-fold increase of the odds of death (HR 2.1, 95% CI 1.6-2.8, p < 0.001), while phenotype 1 was associated with a 71% reduction in the odds of dying (HR 0.29, 95% CI 0.18-0.47, p < 0.001). CONCLUSIONS: Echocardiography-derived phenotypes describing RV remodeling and dysfunction may provide prognostic information which is independent of and additional to the clinically defined risk in incident PAH patients.

Right Ventricular Contractile Reserve: A Key Metric to Identifying When Cardiorespiratory Fitness Will Improve With Pulmonary Vasodilators.

Cardiorespiratory fitness (CRF) has been proposed as a vital sign for the past several years, supported by a wealth of evidence demonstrating its significance as a predictor of health trajectory, exercise/functional capacity, and the quality of life. According to the Fick equation, oxygen consumption (VO2) is the product of cardiac output (CO) and arterial-venous oxygen difference, with the former being a primary driver of one's aerobic capacity. In terms of the dependence of aerobic capacity on a robust augmentation of CO from rest to maximal exercise, left ventricular (LV) CO has been the historic focal point. Patients with pulmonary arterial hypertension (PAH) or secondary pulmonary hypertension (PH) present with a significantly compromised CRF; as pathophysiology worsens, so too does CRF. Interventions to improve pulmonary hemodynamics continue to emerge and are now a standard of clinical care in several patient populations with increased pulmonary pressures; new pharmacologic options continue to be explored. Improvement in CRF/aerobic capacity has been and continues to be a primary or leading secondary endpoint in clinical trials examining the effectiveness of pulmonary vasodilators. A central premise for including CRF/aerobic capacity as an endpoint is that pulmonary vasodilation will lead to a significant downstream increase in LV CO and therefore peak VO2. However, the importance of right ventricular (RV) CO to the peak VO2 response continues to be overlooked. The current review provides an overview of relevant principles of exercise physiology, approaches to assessing RV contractile reserve and proposals for clinical trial design and subject phenotyping.

Idiopathic Pulmonary Arterial Hypertension in Paediatrics Represents Still a Serious Challenge: A Case Series Study.

INTRODUCTION: Paediatric pulmonary hypertension (PH) represents a heterogeneous illness that is responsible for high morbidity and mortality if left without treatment. Idiopathic pulmonary arterial hypertension (IPAH) is a subtype of PAH rarely seen in paediatrics. Limited long-term data are available. METHODS: Over a period of 20 years, 10 paediatric patients were enrolled at two tertiary centres. Their clinical, echocardiographic, and right heart catheterisation (RHC) features and outcome were evaluated. RESULTS: The mean age at first diagnosis was 5.7 ± 5.7 years. The age at the last follow-up was 12.4 ± 6.1 years. The average follow-up was 6.6 ± 0.8 years. There was a female prevalence of 60% (p < 0.05) in this case series. Regarding the NYHA functional class, 80% of IPAH subjects were in class III or IV. The mean saturation was 91 ± 5%. In this regard, 70% of the patients were on a combination of three drugs, with sildenafil (90%) included. On echocardiography, longitudinal right ventricular contractility (TAPSE) was slightly reduced (13.4 ± 2.6 mm), whilst RVSP was severely elevated (101 ± 19 mmHg). The RHC data showed that mPAP was 61.8 ± 23.1 mmHg (p = 0.0017 with RVSP on echocardiography), mRAP was 10.7 ± 3.8 mmHg, CI was 2.6 ± 1 L·min-1·m-2, PVRi was 16.8 ± 12.6 WU·m2, and SVO2 was 63.6 ± 14.8%. Regarding the outcome, two male IPAH patients (20%) died, and 50% underwent lung transplant or were on transplant assessment or already on the waiting list for lung transplantation. One patient underwent a ductus arteriosus stenting (reverse Potts shunt) and another underwent atrial septostomy and stenting. CONCLUSIONS: Notwithstanding the progress in medical therapy, IPAH continues to represent a serious challenge, particularly in the paediatric population, with the need for lung transplantation and significant mortality.

Lung Ultrasound, Echocardiography, and Fluid Challenge for the Differential Diagnosis of Pulmonary Hypertension.

OBJECTIVES: The differential diagnosis between pulmonary arterial hypertension (PAH) and postcapillary pulmonary hypertension (PH) in heart failure with preserved ejection fraction (HFpEF) is sometimes difficult despite guidelines-derived standardized step-by-step diagnostic algorithms. We therefore explored the added value of lung ultrasound to a previously validated echocardiographic score of right heart catheterization measurements. METHODS: Patients referred for PH underwent a right heart catheterization, echocardiography, and lung ultrasound before and after rapid infusion of 7 mL/kg of saline. A 7-point echocardiographic score based on cardiac chamber dimensions and estimates of filling pressures was implemented for the prediction of precapillary PH. Pulmonary congestion was identified by lung ultrasound B lines. RESULTS: The study enrolled 70 patients with PAH and 77 patients with HFpEF. The PAH patients had a higher echocardiographic score (3.5 ± 1.8 vs 1.6 ± 1.5; P < .001). The HFpEF patients had more B lines both before (8.1 ± 4.2 vs 5.1 ± 3.0; P < .001) and after fluid challenge (14.6 ± 5.4 vs 7.6 ± 3.5; P < .001) and a more important increase (Δ) of B lines after fluid challenge (6.5 ± 2.9 vs 2.5 ± 1.6; P < .001). The sensitivity and specificity of the echocardiographic score (cutoff ≥2) alone for PAH were 0.91 and 0.49, respectively (area under the curve of 0.78). The best diagnostic improvement was observed with addition of ΔB lines + E/e' post-fluid challenge to the echocardiographic score, with a significant increase of the area under the curve (0.98) and (with a cutoff given by the presence of echo score ≥2, ΔB lines <4 and E/e' post < 11) a sensitivity of 0.90 (95% CI, 0.83; 0.97) and specificity of 0.84 (95% CI, 0.76; 0.93). CONCLUSIONS: Lung ultrasound combined with echocardiography at baseline and after fluid challenge has an incremental value for the differential diagnosis between PAH and PH-HFpEF.

Association Between Circulating CD4+ T Cell Methylation Signatures of Network-Oriented SOCS3 Gene and Hemodynamics in Patients Suffering Pulmonary Arterial Hypertension.

Pathogenic DNA methylation changes may be involved in pulmonary arterial hypertension (PAH) onset and its progression, but there is no data on potential associations with patient-derived hemodynamic parameters. The reduced representation bisulfite sequencing (RRBS) platform identified N = 631 differentially methylated CpG sites which annotated to N = 408 genes (DMGs) in circulating CD4+ T cells isolated from PAH patients vs. healthy controls (CTRLs). A promoter-restricted network analysis established the PAH subnetwork that included 5 hub DMGs (SOCS3, GNAS, ITGAL, NCOR2, NFIC) and 5 non-hub DMGs (NR4A2, GRM2, PGK1, STMN1, LIMS2). The functional analysis revealed that the SOCS3 gene was the most recurrent among the top ten significant pathways enriching the PAH subnetwork, including the growth hormone receptor and the interleukin-6 signaling. Correlation analysis showed that the promoter methylation levels of each network-oriented DMG were associated individually with hemodynamic parameters. In particular, SOCS3 hypomethylation was negatively associated with right atrial pressure (RAP) and positively associated with cardiac index (CI) (|r|≥ 0.6). A significant upregulation of the SOCS3, ITGAL, NFIC, NCOR2, and PGK1 mRNA levels (qRT-PCR) in peripheral blood mononuclear cells from PAH patients vs. CTRLs was found (P ≤ 0.05). By immunoblotting, a significant upregulation of the SOCS3 protein was confirmed in PAH patients vs. CTRLs (P < 0.01). This is the first network-oriented study which integrates circulating CD4+ T cell DNA methylation signatures, hemodynamic parameters, and validation experiments in PAH patients at first diagnosis or early follow-up. Our data suggests that SOCS3 gene might be involved in PAH pathogenesis and serve as potential prognostic biomarker.

Exercise Stress Echocardiography of the Right Ventricle and Pulmonary Circulation.

BACKGROUND: Exercise echocardiography is used for assessment of pulmonary circulation and right ventricular function, but limits of normal and disease-specific changes remain insufficiently established. OBJECTIVES: The objective of this study was to explore the physiological vs pathologic response of the right ventricle and pulmonary circulation to exercise. METHODS: A total of 2,228 subjects were enrolled: 375 healthy controls, 40 athletes, 516 patients with cardiovascular risk factors, 17 with pulmonary arterial hypertension, 872 with connective tissue diseases without overt pulmonary hypertension, 113 with left-sided heart disease, 30 with lung disease, and 265 with chronic exposure to high altitude. All subjects underwent resting and exercise echocardiography on a semirecumbent cycle ergometer. All-cause mortality was recorded at follow-up. RESULTS: The 5th and 95th percentile of the mean pulmonary artery pressure-cardiac output relationships were 0.2 to 3.5 mm Hg.min/L in healthy subjects without cardiovascular risk factors, and were increased in all patient categories and in high altitude residents. The 5th and 95th percentile of the tricuspid annular plane systolic excursion to systolic pulmonary artery pressure ratio at rest were 0.7 to 2.0 mm/mm Hg at rest and 0.5 to 1.5 mm/mm Hg at peak exercise, and were decreased at rest and exercise in all disease categories and in high-altitude residents. An increased all-cause mortality was predicted by a resting tricuspid annular plane systolic excursion to systolic pulmonary artery pressure <0.7 mm/mm Hg and mean pulmonary artery pressure-cardiac output >5 mm Hg.min/L. CONCLUSIONS: Exercise echocardiography of the pulmonary circulation and the right ventricle discloses prognostically relevant differences between healthy subjects, athletes, high-altitude residents, and patients with various cardio-respiratory conditions. (Right Heart International NETwork During Exercise in Different Clinical Conditions; NCT03041337).

Fluid challenge and balloon occlusion testing in patients with atrial septal defects.

INTRODUCTION: Careful, stepwise assessment is required in all patients with atrial septal defect (ASD) to exclude pulmonary vascular or left ventricular (LV) disease. Fluid challenge and balloon occlusion may unmask LV disease and post-capillary pulmonary hypertension, but their role in the evaluation of patients with 'operable' ASDs is not well established. METHODS: We conducted a prospective study in three Italian specialist centres between 2018 and 2020. Patients selected for percutaneous ASD closure underwent assessment at baseline and after fluid challenge, balloon occlusion and both. RESULTS: Fifty patients (46 (38.2, 57.8) years, 72% female) were included. All had a shunt fraction >1.5, pulmonary vascular resistance (PVR) <5 Wood Units (WU) and pulmonary arterial wedge pressure (PAWP) <15 mm Hg. Individuals with a PVR ≥2 WU at baseline (higher PVR group) were older, more symptomatic, with a higher baseline systemic vascular resistance (SVR) than the lower PVR group (all p<0.0001). Individuals with a higher PVR experienced smaller increases in pulmonary blood flow following fluid challenge (0.3 (0.1, 0.5) vs 2.0 (1.5, 2.8) L/min, p<0.0001). Balloon occlusion led to a more marked fall in SVR (p<0.0001) and a larger increase in systemic blood flow (p=0.024) in the higher PVR group. No difference was observed in PAWP following fluid challenge and/or balloon occlusion between groups; four (8%) patients reached a PAWP ≥18 mm Hg following the addition of fluid challenge to balloon occlusion testing. CONCLUSIONS: In adults with ASD without overt LV disease, even small rises in PVR may have significant implications on cardiovascular haemodynamics. Fluid challenge may provide additional information to balloon occlusion in this setting.