Prognostic value of echocardiographic changes in patients with pulmonary arterial hypertension receiving parenteral prostacyclin therapy

Expert provider survey of longitudinal assessment in patients with pulmonary arterial hypertension

BACKGROUND

Patients suffering from pulmonary arterial hypertension (PAH) demand frequent assessment to keep pace with a dynamic and sometimes rapidly progressive disease course. To improve our understanding of patient monitoring, we conducted a survey of pulmonary hypertension (PH) providers to establish real-world practice patterns.

OBJECTIVE

To evaluate the type and frequency of patient assessment methods employed by expert PH providers following PAH diagnosis METHODS: A descriptive cross-sectional survey of PH providers across the United States was utilized to assess provider practices. Between September 14, 2017 to October 17, 2017, a survey was distributed electronically to PH experts assessing follow-up frequency and testing evaluation of patients with PAH.

RESULTS

40 (11.4%) providers completed the survey, representing cardiologists, pulmonologists, and advanced practice providers at centers who cared for an average of 95 patients per year with PAH. Follow-up testing and clinic evaluation was influenced by severity of patient illness. Frequency of re-assessment of clinic follow-up, six-minute walk test, echocardiogram, brain natriuretic peptide, and right heart catheterization in various clinical scenarios all reflected disparate practice.

CONCLUSIONS

Current clinical practice patterns in the monitoring of patients with PAH are variable and do not necessarily reflect guideline-based practices, suggesting the need for further research and improved guidelines on the frequency of follow up and repeat testing.

Echocardiography in Pulmonary Arterial Hypertension: Is It Time to Reconsider Its Prognostic Utility?

Pulmonary arterial hypertension (PAH) is characterized by an insult in the pulmonary vasculature, with subsequent right ventricular (RV) adaptation to the increased afterload that ultimately leads to RV failure. The awareness of the importance of RV function in PAH has increased considerably because right heart failure is the predominant cause of death in PAH patients. Given its wide availability and reduced cost, echocardiography is of paramount importance in the evaluation of the right heart in PAH. Several echocardiographic parameters have been shown to have prognostic implications in PAH; however, the role of echocardiography in the risk assessment of the PAH patient is limited under the current guidelines. This review discusses the echocardiographic evaluation of the RV in PAH and during therapy, and its prognostic implications, as well as the potential significant role of repeated echocardiographic assessment in the follow-up of patients with PAH.

Mixed Venous Oxygen Saturation Is a Better Prognosticator Than Cardiac Index in Pulmonary Arterial Hypertension

BACKGROUND

European Society of Cardiology (ESC) and European Respiratory Society (ERS) guidelines include thermodilution cardiac index (TDCI) and mixed venous oxygen saturation (SvO₂) as two of the three hemodynamic determinations used in risk assessment of patients with pulmonary arterial hypertension (PAH). SvO₂ may be a better measurement than TDCI to assess prognosis in patients with either idiopathic or heritable PAH.

RESEARCH QUESTION

What is the concordance between TDCI and SvO₂ ESC/ERS risk group allocation and their prognostic value in patients with PAH?

STUDY DESIGN AND METHODS

In this retrospective study, we assessed the correlation between SvO₂ and TDCI in patients with idiopathic and heritable PAH. We determined concordance in the ESC/ERS risk group allocation and association with survival, both at baseline and follow-up.

RESULTS

A total of 158 patients (mean age, 58 ± 17 years; 72% women) with idiopathic (91%) and heritable (9%) PAH were included. There was moderate association between TDCI and SvO₂ (r = 0.50; 95% CI, 0.37-0.62). Weighted kappa revealed a fair agreement between TDCI and SvO₂ (κ = 0.30; 95% CI, 0.18-0.42), with concordance in risk group allocation in 49% of patients. During a median follow-up of 45 months (interquartile range, 23-105), 62 patients (39%) died. Using Kaplan-Meier analysis, survival was impacted by the SvO₂ (log rank = 0.002) but not by the TDCI risk group allocation (log-rank = 0.51). Using the Cox proportional hazard model, adjusted for age and sex, SvO₂ (but not TDCI) was associated with mortality (hazard ratio per 1% change, 0.94; 95% CI, 0.91-0.97; P < .001).

INTERPRETATION

When using the cutoffs proposed by the ESC/ERS guidelines, we noted poor concordance in risk score allocation between TDCI and SvO₂. In patients with idiopathic or heritable PAH, SvO₂ measurements are superior to TDCI in predicting long-term mortality.

Ventricular-ventricular interaction variables correlate with surrogate variables of clinical outcome in children with pulmonary hypertension

Determination of biventricular dimensions, function, and ventricular–ventricular interactions (VVI) is an essential part of the echocardiographic examination in adults with pulmonary hypertension (PH); however, data from according pediatric studies are sparse. We hypothesized that left and right heart dimensions/function and VVI variables indicate disease severity and progression in children with PH. Left heart, right heart, and VVI variables (e.g. end-systolic LV eccentricity index [LVEI], right ventricular [RV]/left ventricular [LV] dimension ratio) were echocardiographically determined in 57 children with PH, and correlated with New York Heart Association (NYHA) functional class (FC), N-terminal-pro brain natriuretic peptide (NT-proBNP), and invasive hemodynamic variables (e.g. pulmonary vascular resistance index [PVRi]). Clinically sicker patients (higher NYHA FC) had lower LV ejection fraction (LVEF) and higher LVEI – a surrogate of LV compression. In PH children, the ratio of systolic pulmonary arterial pressure divided by systolic systemic arterial pressure (sPAP/sSAP) and the PVRi correlated well with the LVEI (P < 0.001). Patients with more severe PH (sPAP/sSAP ratio, PVRi) had increased RV/LV and right-to-left atrial dimension ratios (P < 0.01). When stratified using NYHA-FC, sicker PH children had greater RV and right atrial dimensions with lower exercise capacity, while the tricuspid annular plane systolic excursion as surrogate for longitudinal systolic RV function decreased. Consistent with previous studies, serum NT-proBNP correlated with both, sPAP/sSAP ratio (P < 0.001) and NYHA FC (P < 0.01). Taken together, the VVI variables LVEI and RV/LV dimension ratio are associated with lower FC, worse hemodynamics, and higher NT-proBNP levels, thus highlighting the importance of ventricular interdependence in pediatric PH.

Non-invasive Multimodality Cardiovascular Imaging of the Right Heart and Pulmonary Circulation in Pulmonary Hypertension

Pulmonary hypertension (PH) is defined as resting mean pulmonary arterial pressure (mPAP) ≥25 millimeters of mercury (mmHg) via right heart (RH) catheterization (RHC), where increased afterload in the pulmonary arterial vasculature leads to alterations in RH structure and function. Mortality rates have remained high despite therapy, however non-invasive imaging holds the potential to expedite diagnosis and lead to earlier initiation of treatment, with the hope of improving prognosis. While historically the right ventricle (RV) had been considered a passive chamber with minimal role in the overall function of the heart, in recent years in the evaluation of PH and RH failure the anatomical and functional assessment of the RV has received increased attention regarding its performance and its relationship to other structures in the RH-pulmonary circulation. Today, the RV is the key determinant of patient survival. This review provides an overview and summary of non-invasive imaging methods to assess RV structure, function, flow, and tissue characterization in the setting of imaging's contribution to the diagnostic, severity stratification, prognostic risk, response of treatment management, and disease surveillance implications of PH's impact on RH dysfunction and clinical RH failure.

Efficacy of treprostinil in the SU5416-hypoxia model of severe pulmonary arterial hypertension: haemodynamic benefits are not associated with improvements in arterial remodelling

BACKGROUND AND PURPOSE

Pulmonary arterial hypertension (PAH) is a life-threatening disease that leads to progressive pulmonary hypertension, right heart failure and death. Parenteral prostaglandins (PGs), including treprostinil, a prostacyclin analogue, represent the most effective medical treatment for severe PAH. We investigated the effect of treprostinil on established severe PAH and underlying mechanisms using the rat SU5416 (SU, a VEGF receptor-2 inhibitor)-chronic hypoxia (Hx) model of PAH.

EXPERIMENTAL APPROACH

Male Sprague Dawley rats were injected with SU (20 mg·kg^-1 , s.c.) followed by 3 weeks of Hx (10% O₂ ) to induce severe PAH. Four weeks post-SU injection, baseline right ventricular (RV) systolic pressure (RVSP) was measured, and the rats were randomized to receive vehicle or treprostinil treatment (Trep-100: 100 ng·kg^-1 ·min^-1 or Trep-810: 810 ng·kg^-1 ·min^-1 ). Following 3 weeks of treatment, haemodynamic and echocardiographic assessments were performed, and tissue samples were collected for protein expression and histological analysis.

KEY RESULTS

At week 7, no difference in RVSP or RV hypertrophy was observed between vehicle and Trep-100; however, Trep-810 significantly reduced RVSP and RV hypertrophy. Trep-810 treatment significantly improved cardiac structure and function. Further, a short-term infusion of treprostinil in rats with established PAH at 4 weeks post-SU produced an acute, dose-dependent reduction in RVSP consistent with a vasodilator effect. However, chronic Trep-810 treatment did not alter media wall thickness, degree of vascular occlusion or total vessel count in the lungs.

CONCLUSIONS AND IMPLICATIONS

Treprostinil exerts therapeutic benefits in PAH through decreased vascular resistance and improved cardiac structure and function; however, treprostinil treatment does not have direct impact vascular remodelling.

ECG Markers of Hemodynamic Improvement in Patients with Pulmonary Hypertension

Introduction

Several diagnostic tests have been recommended for risk assessment in pulmonary hypertension (PH), but the role of electrocardiography (ECG) in monitoring of PH patients has not been yet established. Therefore the aim of the study was to evaluate which ECG patterns characteristic for pulmonary hypertension can predict hemodynamic improvement in patients treated with targeted therapies.

Methods

Consecutive patients with pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH) were eligible to be included if they had had performed two consecutive right heart catheterization (RHC) procedures before and after starting of targeted therapies. Patients were followed up from June 2009 to July 2017. ECG patterns of right ventricular hypertrophy according to American College of Cardiology Foundation were assessed.

Results

We enrolled 80 patients with PAH and 11 patients with inoperable CTEPH. The follow-up RHC was performed within 12.6 ± 10.0 months after starting therapy. Based on median change of pulmonary vascular resistance, we divided our patients into two subgroups: with and without significant hemodynamic improvement. R_V1, max⁡R_V1,2 + max⁡S_I,aVL − S_V1, and P_II improved along with the improvement of hemodynamic parameters including PVR. They predicted hemodynamic improvement with similarly good accuracy as shown in ROC analysis: R_V1 (AUC: 0.75; 95% CI: 0.63–0.84), P_II (AUC: 0.67, 95% CI: 0.56–0.77), and max⁡R_V1,2 + max⁡S_I,aVL − S_V1 (0.73; 95% CI: 0.63–0.82). In Cox regression only change in R_V1 remained significant mortality predictor (HR: 1.12, 95% CI: 1.01–1.24).

Conclusion

Electrocardiogram may be useful in predicting hemodynamic effects of targeted therapy in precapillary pulmonary hypertension. Decrease of R_V1, max⁡R_V1,2 + max⁡S_I,aVL − S_V1, and P_II corresponds with hemodynamic improvement after treatment. Of these changes a decrease of R wave amplitude in V₁ is associated with better survival.

The right ventricular outflow tract in pediatric pulmonary hypertension-Data from the European Pediatric Pulmonary Vascular Disease Network

OBJECTIVE

The right ventricular outflow tract (RVOT) is pivotal for adequate RV function and known to be adversely affected by elevated pulmonary arterial pressure (PAP) in adults with pulmonary hypertension (PH). Aim of this study was to determine the effects of increased RV pressure afterload in children with PH on RVOT size, function, and flow parameters.

METHODS

We conducted a transthoracic echocardiographic study in 51 children with PH (median age: 5.3 years; range 1.5 months to 18 years) and determined the following RVOT variables: RVOT diameter, RVOT velocity time integral (VTI), ratio of tricuspid regurgitation velocity (TRV)/RVOT VTI, and RVOT systolic excursion (SE).

RESULTS

In our pediatric PH cohort, the age-specific RVOT diameter z-score was higher compared to normal values. Deviation from normal RVOT diameter values increased with age, disease severity, and New York Heart Association functional class. Significant correlations were found between RVOT diameter and the RV end-diastolic area and right atrial area. The age-specific RVOT VTIz-score values were significantly lower in children with PH vs healthy controls. The TRV/RVOT VTI ratio increased with rising systolic RV pressure, while the RVOT SE was similar between PH children and control subjects.

CONCLUSIONS

In pediatric PH cohort, the RVOT VTI is decreased, and the TRV/RVOT VTI ratio and the RVOT diameter increased compared to healthy subjects. Assessment of RVOT variables, together with established RV parameters, allows for a comprehensive assessment of global right heart size and performance in children with PH.

Follow-Up of Pulmonary Hypertension With Echocardiography

Individual patient response to effective therapies for pulmonary hypertension (PAH) is variable and difficult to quantify. Consequently, management decisions regarding initiation and continuation of therapy are highly dependent on the results of investigations. Registry data show that changes in cardiac index, mean right atrial pressure, and mean pulmonary artery pressure have the greatest influence on survival. It is recognized that pulmonary artery pressure (PASP) responses to PAH-specific drugs are heterogeneous. However, follow-up testing is strongly focused on assessing changes in PASP and functional status (6-min walk). The goals of therapy, which should be highlighted in follow-up imaging, include not only reduction of PASP, decrease in pulmonary vascular resistance, and improvements in right ventricular function, cardiac output, and tricuspid regurgitation. This paper reviews the echocardiographic follow-up of pulmonary hypertension, and especially focuses on right ventricular function-a major determinant of outcome, for which reliable echocardiographic assessment has become more feasible.

Diagnostics in Children and Adolescents with Suspected or Confirmed Pulmonary Hypertension

We provide a practical approach on the initial assessment and diagnostic work-up of children and adolescents with pulmonary hypertension (PH). Transthoracic echocardiography (TTE) often serves as initial study tool before invasive cardiac catheterization. Misinterpretation of TTE variables may lead to missed or delayed diagnosis with devastating consequences, or unnecessary invasive diagnostics that have inherited risks. In addition to clinical and biochemical markers, serial examination of patients with PH using a standardized TTE approach, determining conventional and novel echocardiographic variables, may allow early diagnosis and treatment in paediatric PH. Cardiac magnetic resonance imaging and computed tomography represent important non-invasive imaging modalities, that together with TTE may enable comprehensive assessment of ventricular function and pulmonary hemodynamics. Invasive assessment of haemodynamics (ventricular, pulmonary) and testing of acute vasoreactivity in the catheterization laboratory is still the gold standard for the diagnosis of PH and pulmonary hypertensive vascular disease (PHVD) in children and for the initiation of specific PH therapy. We suggest the regular assessment of prognostic TTE variables as part of a standardized approach for initial diagnosis of children with PH. Overreliance on any single TTE variable should be avoided as it detracts from the overall diagnostic potential of a standardized TTE examination for PH.

Echocardiographic findings associated with mortality ortransplant in patients with pulmonary arterial hypertension:A systematic review and meta-analysis

Background

Identification of patients at risk of deterioration is essential to guide clinical management in pulmonary arterial hypertension (PAH). This study aims to provide a comprehensive overview of well-investigated echocardiographic findings that are associated with clinical deterioration in PAH.

Methods

MEDLINE and EMBASE databases were systematically searched for longitudinal studies published by April 2015 that reported associations between echocardiographic findings and mortality, transplant or clinical worsening. Meta-analysis using random effect models was performed for echocardiographic findings investigated by four or more studies. In case of statistical heterogeneity a sensitivity analysis was conducted.

Results

Thirty-seven papers investigating 51 echocardiographic findings were included. Meta-analysis of univariable hazard ratios (HRs) and sensitivity analysis showed that presence of pericardial effusion (pooled HR 1.70; 95 % CI 1.44–1.99), right atrial area (pooled HR 1.71; 95 % CI 1.38–2.13) and tricuspid annular plane systolic excursion (TAPSE; pooled HR 1.72; 95 % CI 1.34–2.20) were the most well-investigated and robust predictors of mortality or transplant.

Conclusions

This meta-analysis substantiates the clinical yield of specific echocardiographic findings in the prognostication of PAH patients in day-to-day practice. In particular, pericardial effusion, right atrial area and TAPSE are of prognostic value.

Electronic supplementary material

The online version of this article (doi: 10.1007/s12471-016-0845-3) contains supplementary material, which is available to authorized users.

Transthoracic echocardiography in the evaluation of pediatric pulmonary hypertension and ventricular dysfunction

Transthoracic echocardiography (TTE) is the most accessible noninvasive diagnostic procedure for the initial assessment of pediatric pulmonary hypertension (PH). This review focuses on principles and use of TTE to determine morphologic and functional parameters that are also useful for follow-up investigations in pediatric PH patients. A basic echocardiographic study of a patient with PH commonly includes the hemodynamic calculation of the systolic pulmonary artery pressure (PAP), the mean and diastolic PAP, the pulmonary artery acceleration time, and the presence of a pericardial effusion. A more detailed TTE investigation of the right ventricle (RV) includes assessment of its size and function. RV function can be evaluated by RV longitudinal systolic performance (e.g., tricuspid annular plane systolic excursion), the tricuspid regurgitation velocity/right ventricular outflow tract velocity time integral ratio, the fractional area change, tissue Doppler imaging-derived parameters, strain measurements, the systolic-to-diastolic duration ratio, the myocardial performance (Tei) index, the RV/left ventricle (LV) diameter ratio, the LV eccentricity index, determination of an enlarged right atrium and RV size, and RV volume determination by 3-dimensional echocardiography. Here, we discuss the potential use and limitations of TTE techniques in children with PH and/or ventricular dysfunction. We suggest a protocol for TTE assessment of PH and myocardial function that helps to identify PH patients and their response to pharmacotherapy. The outlined protocol focuses on the detailed assessment of the hypertensive RV; RV-LV crosstalk must be analyzed separately in the evaluation of different pathologies that account for pediatric PH.

Echocardiographic Reference Values for Right Atrial Size in Children with and without Atrial Septal Defects or Pulmonary Hypertension

Right atrial (RA) size may become a very useful, easily obtainable, echocardiographic variable in patients with congenital heart disease (CHD) with right-heart dysfunction; however, according studies in children are lacking. We investigated growth-related changes of RA dimensions in healthy children. Moreover, we determined the predictive value of RA variables in both children with secundum atrial septal defect (ASD) and children with pulmonary hypertension (PH) secondary to CHD (PH-CHD). This is a prospective study in 516 healthy children, in 80 children with a secundum ASD (>7 mm superior-inferior dimension), and in 42 children with PH-CHD. We determined three RA variables, i.e., end-systolic major-axis length, end-systolic minor-axis length, and end-systolic area, stratified by age, body weight, length, and surface area. RA end-systolic length and area z scores were increased in children with ASD and PH-CHD when compared to those variables in the healthy control population. Using the Youden Index to determine the best cutoff scores in sex- and age-specific RA dimensions, we observed a sensitivity and specificity up to 94 and 91 %, respectively, in ASD children and 98 and 94 %, respectively, in PH-CHD children. We provide normal values (z scores -2 to +2) for RA size and area in a representative, large pediatric cohort. Enlarged RA variables with scores >+2 were predictive of secundum ASD and PH-CHD. Two-dimensional determination of RA size can identify enlarged RAs in the setting of high volume load (ASD) or pressure load (PH-CHD).

Cardiac magnetic resonance findings predicting mortality in patients with pulmonary arterial hypertension: a systematic review and meta-analysis

Objectives

To provide a comprehensive overview of all reported cardiac magnetic resonance (CMR) findings that predict clinical deterioration in pulmonary arterial hypertension (PAH).

Methods

MEDLINE and EMBASE electronic databases were systematically searched for longitudinal studies published by April 2015 that reported associations between CMR findings and adverse clinical outcome in PAH. Studies were appraised using previously developed criteria for prognostic studies. Meta-analysis using random effect models was performed for CMR findings investigated by three or more studies.

Results

Eight papers (539 patients) investigating 21 different CMR findings were included. Meta-analysis showed that right ventricular (RV) ejection fraction was the strongest predictor of mortality in PAH (pooled HR 1.23 [95 % CI 1.07–1.41], p = 0.003) per 5 % decrease. In addition, RV end-diastolic volume index (pooled HR 1.06 [95 % CI 1.00–1.12], p = 0.049), RV end-systolic volume index (pooled HR 1.05 [95 % CI 1.01–1.09], p = 0.013) and left ventricular end-diastolic volume index (pooled HR 1.16 [95 % CI 1.00–1.34], p = 0.045) were of prognostic importance. RV and LV mass did not provide prognostic information (p = 0.852 and p = 0.983, respectively).

Conclusion

This meta-analysis substantiates the clinical yield of specific CMR findings in the prognostication of PAH patients. Decreased RV ejection is the strongest and most well established predictor of mortality.

Key Points

• Cardiac magnetic resonance imaging is useful for prognostication in pulmonary arterial hypertension.

• Right ventricular ejection fraction is the strongest predictor of mortality.

• Serial CMR evaluation seems to be of additional prognostic importance.

• Accurate prognostication can aid in adequate and timely intensification of PAH-specific therapy.

Electronic supplementary material

The online version of this article (doi:10.1007/s00330-016-4217-6) contains supplementary material, which is available to authorized users.

Right atrial pressure/pulmonary artery wedge pressure ratio: A more specific predictor of survival in pulmonary arterial hypertension

BACKGROUND

Pulmonary arterial hypertension (PAH) is a progressive, fatal disease. Current prognostic models are not ideal, and identifying more accurate prognostic variables is needed. The objective of this study was to evaluate the relative prognostic value of the right atrial pressure/pulmonary artery wedge pressure (RAP/PAWP) ratio in PAH patients. We hypothesized that the RAP/PAWP ratio is more predictive of survival than any of the other measured or calculated hemodynamic variables.

METHODS

We performed a secondary analysis of a PAH cohort (Cohort 1) and validated our results in a separate cohort (Cohort 2). Cohort 1 included primarily patients enrolled in prospective, short-term, randomized clinical trials and subsequently followed long term. Cohort 2 included patients prospectively enrolled in a PAH registry at a tertiary PAH referral center.

RESULTS

Cohort 1 (n = 847) and Cohort 2 (n = 697) had a mean age of 47 and 54 years, respectively. Most were female (78% and 73%, respectively), Caucasian (83% and 82%), with advanced functional class disease status (New York Heart Association Functional Class III/IV 85% and 68%) and with significantly elevated hemodynamics (mean RAP/PAWP ratio: 1.2 and 1.0; pulmonary vascular resistance: 13.5 and 9.4 Wood units). RAP/PAWP ratio indicated a 1-year hazard ratio of 1.44 (p = 0.0001) and 1.35, respectively (p < 0.0001), and was the most consistently predictive hemodynamic variable across the 2 cohorts. These results remain valid even when adjusted for other covariables in multivariable regression models.

CONCLUSIONS

The RAP/PAWP ratio is a more specific predictor of survival than any other hemodynamic variable, and we recommend that it be used in clinical prognostication and PAH predictive models.

Pulmonary arterial wall thickness in Eisenmenger Syndrome: Prospective, cross-sectional, controlled clinical trial

BACKGROUND

The aim of current study is to investigate echocardiographic pulmonary artery wall thickness (PAWT) association with angiocardiography, echocardiography, and biochemical findings and to demonstrate its predictive role in morbidity of disease.

METHOD

Nineteen patients with Eisenmenger Syndrome (ES) (13 females; a mean age of 12.0 ± 4.1 [min-max 4-17] years) and 24 (16 females; a mean age of 12.1 ± 4.3 [min-max 3-18 years]) healthy subjects as a control group were included in this prospective, cross-sectional, controlled clinical study between December, 2012 and December, 2013. PAWT were measured at the end of systole at the distal site of pulmonary valves at the parasternal short-axis. PAWT was compared with morbidity criteria of the disease such as functional class, pulmonary vascular resistance.

RESULTS

PAWT was higher in the patient group (P = 0.005) together with pulmonary arterial diameter (Z-score, P < 0.001), vena cava inferior diameter (P = 0.002), and right ventricular wall thickness (RVWT), while TAPSE was significantly lower (P = 0.002). PAWT was strongly positively correlated to RVWT (r = 0.893, P < 0.001) and moderate negatively correlated to TAPSE (r = 0.597; P < 0.011).

CONCLUSION

PAWT can be used as an additional parameter with other echocardiographic parameters in the follow-up of Eisenmenger Syndrome in children.

Imaging the heart in pulmonary hypertension: an update

Noninvasive imaging of the heart plays an important role in the diagnosis and management of pulmonary hypertension (PH), and several well-established techniques are available for assessing performance of the right ventricle, the key determinant of patient survival. While right heart catheterisation is mandatory for establishing a diagnosis of PH, echocardiography is the most important screening tool for early detection of PH. Cardiac magnetic resonance imaging (CMRI) is also a reliable and practical tool that can be used as part of the diagnostic work-up. Echocardiography can measure a range of haemodynamic and anatomical variables (e.g. pericardial effusion and pulmonary artery pressure), whereas CMRI provides complementary information to echocardiography via high-resolution, three-dimensional imaging. Together with echocardiography and CMRI, techniques such as high-resolution computed tomography and positron emission tomography may also be valuable for screening, monitoring and follow-up assessments of patients with PH, but their clinical relevance has yet to be established. Technological advances have produced new variants of echocardiography, CMRI and positron emission tomography, and these permit closer examination of myocardial architecture, motion and deformation. Integrating these new tools into clinical practice in the future may lead to more precise noninvasive determination of diagnosis, risk and prognosis for PH.

Right Ventricular Outflow Tract Velocity Time Integral Determination in 570 Healthy Children and in 52 Pediatric Atrial Septal Defect Patients

Determination of the right ventricular outflow tract velocity time integral (RVOT VTI) is an important part of the noninvasive investigation of pulmonary blood flow in adults; however, age-related pediatric reference data are lacking. We examined growth-related changes of RVOT VTI values in children and the predictive value of RVOT VTI values in identifying enhanced pulmonary blood flow in children with secundum type atrial septal defect (ASD). A prospective study was conducted in a group of 570 healthy children and 52 children with a moderate-sized to large ASD. We determined the effects of age, body length (BL), body weight (BW), and body surface area (BSA) on RVOT VTI values. The predictive value of normal values stratified for age, BW, BL, and BSA was tested in our 52 ASD children. RVOT VTI values ranged from mean 9.7 ± 1.2 cm in neonates to 23.3 ± 2.7 cm in children with 18 years of age and showed a positive correlation with age, BL, BSA, and BW. In our population, RVOT VTI z-scores showed a high specificity for detecting ASD patients (>97 %) with sensitivity up to 71 %. We provide normal ranges and calculated z-scores of pediatric RVOT VTI values. Normal RVOT VTI z-scores might be additional predictors in identifying increased pulmonary blood flow in patients with ASD.

Reference values and calculation of z-scores of echocardiographic measurements of the normal pediatric right ventricle

Determination of right ventricular (RV) size and function has gained more interest in recent years in adults and children, especially in patients with congenital heart disease. Data on normal RV size parameters in children are scant. The aim of this study was to investigate growth-related changes in RV internal dimensions in a healthy pediatric cohort and the predictive value of RV parameters in identifying enlarged right ventricles in children with secundum-type atrial septal defects (ASD). A prospective study was conducted in a group of 576 healthy children (aged 1 day to 18 years) and 37 children (aged 1.4 to 17.7 years) with moderate-sized to large ASDs. The effects of age, body length, body weight, and body surface area were determined on the following RV parameters: end-diastolic basal diameter, end-diastolic midcavity diameter, end-diastolic length, end-systolic length, end-diastolic area, and end-systolic area. The predictive value of normal values stratified for age, body weight, body length, and body surface area was tested in children with ASDs. RV end-diastolic basal diameter, end-diastolic midcavity diameter, end-diastolic length, end-systolic length, end-diastolic area, and end-systolic area showed positive correlations with age, body length, body surface area, and body weight. In this population, RV z scores showed high specificity for detecting patients with ASDs, with sensitivity up to 89%, especially in children <8 years of age. In conclusion, the normal ranges of pediatric RV internal dimensions are provided. The z scores of these RV parameters were also calculated. Normal RV z scores might be important predictors in identifying enlarged right ventricles in patients with ASDs.

Echocardiography in pediatric pulmonary hypertension

Pulmonary hypertension (PH) can be a rapidly progressive and fatal disease. Although right heart catheterization remains the gold standard in evaluation of PH, echocardiography remains an important tool in screening, diagnosing, evaluating, and following these patients. In this article, we will review the important echocardiographic parameters of the right heart in evaluating its anatomy, hemodynamic assessment, systolic, and diastolic function in children with PH.