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

Exercise Pulmonary Hypertension in Heart Valve Disease

The optimal management of heart valve disease (HVD) is still debated and many studies are underway to identify the best time to refer patients for the most appropriate treatment strategy (either conservative, surgical or transcatheter interventions). Exercise pulmonary hypertension (PH) can be detected during exercise stress echocardiography (ESE) and has been demonstrated to have an important prognostic role in HVD, by predicting symptoms and mortality. This review article aims to provide an overview on the prognostic role of exercise PH in valvulopathies, and its possible role in the diagnostic-therapeutic algorithm for the management of HVD.

Validation of Echocardiographic Measurements in Patients with Pulmonary Embolism in the RIETE Registry

Background  In acute pulmonary embolism (PE), echocardiographic identification of right ventricular (RV) dysfunction will inform prognostication and clinical decision-making. Registro Informatizado Enfermedad TromboEmbolica (RIETE) is the world's largest registry of patients with objectively confirmed PE. The reliability of site-reported RV echocardiographic measurements is unknown. We aimed to validate site-reported key RV echocardiographic measurements in the RIETE registry. Methods  Fifty-one randomly chosen patients in RIETE who had transthoracic echocardiogram (TTE) performed for acute PE were included. TTEs were de-identified and analyzed by a core laboratory of two independent observers blinded to site-reported data. To investigate reliability, intraclass correlation coefficients (ICCs) and Bland-Altman plots between the two observers, and between an average of the two observers and the RIETE site-reported data were obtained. Results  Core laboratory interobserver variations were very limited with correlation coefficients >0.8 for all TTE parameters. Agreement was substantial between core laboratory observers and site-reported data for key parameters including tricuspid annular plane systolic excursion (ICC 0.728; 95% confidence interval [CI], 0.594-0.862) and pulmonary arterial systolic pressure (ICC 0.726; 95% CI, 0.601-0.852). Agreement on right-to-left ventricular diameter ratio (ICC 0.739; 95% CI, 0.443-1.000) was validated, although missing data limited the precision of the estimates. Bland-Altman plots showed differences close to zero. Conclusion  We showed substantial reliability of key RV site-reported measurements in the RIETE registry. Ascertaining the validity of such data adds confidence and reliability for subsequent investigations.

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).

Echocardiographic determination of right ventricular volumes and ejection fraction: Validation of a truncated cone and rhomboid pyramid formula

BACKGROUND

Echocardiographic assessment of right ventricular (RV) measurements may be challenging. The aim of this study was to develop a formula for calculation of RV volumes and function based on measurements of linear dimensions by 2-dimensional (2D) transthoracic echocardiography (TTE) in comparison to cardiovascular magnetic resonance (CMR).

METHODS

129 consecutive patients with standard TTE and RV analysis by CMR were included. A formula based on the geometric assumptions of a truncated cone minus a truncated rhomboid pyramid was developed for calculations of RV end-diastolic volume (EDV) and RV end-systolic volume (ESV) by using the basal diameter of the RV (Dd and Ds) and the baso-apical length (Ld and Ls) in apical 4-chamber TTE views: RV EDV = 1.21 * Dd2 * Ld, and RV ESV = 1.21 * Ds2 * Ls.

RESULTS

Calculations of RV EDV (ΔRV EDV = 10.2±26.4 ml to CMR, r = 0.889), RV ESV (ΔRV ESV = 4.5±18.4 ml to CMR, r = 0.921) and RV EF (ΔRV EF = 0.5±4.0% to CMR, r = 0.905) with the cone-pyramid formula (CPF) highly agreed with CMR. Impaired RV function on CMR (n = 52) was identified with a trend to higher accuracy by CPF than by conventional echocardiographic parameters (tricuspid annular plane systolic excursion (TAPSE) and fractional area change (FAC)).

CONCLUSION

Calculations of RV volumes and RV function by 2D TTE with the newly developed CPF were in high concordance to measurements by CMR. Accuracy for detection of patients with reduced RV function were higher by the proposed 2D TTE CPF method than by conventional echocardiographic parameters of TAPSE and RV FAC.

Right Heart Pulmonary Circulation Unit Response to Exercise in Patients with Controlled Systemic Arterial Hypertension: Insights from the RIGHT Heart International NETwork (RIGHT-NET)

BACKGROUND

Systemic arterial hypertension (HTN) is the main risk factor for the development of heart failure with preserved ejection fraction (HFpEF). The aim of the study was was to assess the trends in PASP, E/E' and TAPSE during exercise Doppler echocardiography (EDE) in hypertensive (HTN) patients vs. healthy subjects stratified by age.

METHODS

EDE was performed in 155 hypertensive patients and in 145 healthy subjects (mean age 62 ± 12.0 vs. 54 ± 14.9 years respectively, p < 0.0001). EDE was undertaken on a semi-recumbent cycle ergometer with load increasing by 25 watts every 2 min. Left ventricular (LV) and right ventricular (RV) dimensions, function and hemodynamics were evaluated.

RESULTS

Echo-Doppler parameters of LV and RV function were lower, both at rest and at peak exercise in hypertensives, while pulmonary hemodynamics were higher as compared to healthy subjects. The entire cohort was then divided into tertiles of age: at rest, no significant differences were recorded for each age group between hypertensives and normotensives except for E/E' that was higher in hypertensives. At peak exercise, hypertensives had higher pulmonary artery systolic pressure (PASP) and E/E' but lower tricuspid annular plane systolic excursion (TAPSE) as age increased, compared to normotensives. Differences in E/E' and TAPSE between the 2 groups at peak exercise were explained by the interaction between HTN and age even after adjustment for baseline values (p < 0.001 for E/E', p = 0.011 for TAPSE). At peak exercise, the oldest group of hypertensive patients had a mean E/E' of 13.0, suggesting a significant increase in LV diastolic pressure combined with increased PASP.

CONCLUSION

Age and HTN have a synergic negative effect on E/E' and TAPSE at peak exercise in hypertensive subjects.

Age-changes in right ventricular function-pulmonary circulation coupling: from pediatric to adult stage in 1899 healthy subjects. The RIGHT Heart International NETwork (RIGHT-NET)

The present study analyzes age-specific changes in RV function and RV-PA coupling in a large cohort of apparently healthy subjects with a wide age-range, to identify reference values and to study the influence of clinical and echocardiographic cofactors. 1899 Consecutive healthy subjects underwent a standardized transthoracic echocardiographic examination. Tricuspid annular plane systolic excursion (TAPSE) and systolic pulmonary artery pressure (SPAP) were measured. Ventriculo-arterial coupling was then inferred from the TAPSE/SPAP ratio. A quantile regression analysis was used to estimate quantiles 0.05, 0.10, 0.50 (median), 0.90, and 0.95 of TAPSE, SPAP and TAPSE/SPAP. The association between age and each of these values was determined. The mean age of the group was 45.2 ± 18.5 years (range 1 to 102 years), 971 were males. SPAP increased with age, whereas TAPSE and TAPSE/SPAP ratio decreased. Upon multivariate modeling, the most significant positive associations for TAPSE were body surface area (BSA) driven by the pediatric group, stroke volume (SV), E/A and negatively heart rate and E/e' ratio. SPAP was positively associated with increasing age, SV, E/A, E/e' and negatively with BSA. TAPSE/SPAP ratio was negatively associated with age, female sex, and E/e' and positively with BSA. A preserved relationship between TAPSE and SPAP was found across the different age groups. TAPSE, SPAP and TAPSE/SPAP demonstrate important trends and associations with advancing age, impaired diastolic function, affected by female sex and BSA However the relationship between TAPSE and SPAP is relatively well preserved across the age spectrum.

Feasibility of semi-recumbent bicycle exercise Doppler echocardiography for the evaluation of the right heart and pulmonary circulation unit in different clinical conditions: the RIGHT heart international NETwork (RIGHT-NET)

Exercise Doppler echocardiography (EDE) is a well-validated tool in ischemic and valvular heart diseases. However, its use in the assessment of the right heart and pulmonary circulation unit (RH-PCU) is limited. The aim of this study is to assess the semi-recumbent bicycle EDE feasibility for the evaluation of RH-PCU in a large multi-center population, from healthy individuals and elite athletes to patients with overt or at risk of developing pulmonary hypertension (PH). From January 2019 to July 2019, 954 subjects [mean age 54.2 ± 16.4 years, range 16-96, 430 women] underwent standardized semi-recumbent bicycle EDE with an incremental workload of 25 watts every 2 min, were prospectively enrolled among 7 centers participating to the RIGHT Heart International NETwork (RIGHT-NET). EDE parameters of right heart structure, function and pressures were obtained according to current recommendations. Right ventricular (RV) function at peak exercise was feasible in 903/940 (96%) by tricuspid annular plane systolic excursion (TAPSE), 667/751 (89%) by tissue Doppler-derived tricuspid lateral annular systolic velocity (S') and 445/672 (66.2%) by right ventricular fractional area change (RVFAC). RV-right atrial pressure gradient [RV-RA gradient = 4 × tricuspid regurgitation velocity² (TRV)] was feasible in 894/954 patients (93.7%) at rest and in 816/954 (85.5%) at peak exercise. The feasibility rate in estimating pulmonary artery pressure improved to more than 95%, if both TRV and/or right ventricular outflow tract acceleration time (RVOT AcT) were considered. In high specialized echocardiography laboratories semi-recumbent bicycle EDE is a feasible tool for the assessment of the RH-PCU pressure and function.