The evaluation of right ventricular systolic function in patients with repaired Tetralogy of Fallot by conventional echocardiographic methods and speckle tracking echocardiography: Compared with the gold standard cardiac mangenetic resonance

Machine learning prediction of right ventricular volume and ejection fraction from two-dimensional echocardiography in patients with pulmonary regurgitation

Right ventricular (RV) end-diastolic volume (RVEDV) and ejection fraction (RVEF) by cardiac MRI (cMRI) guide management in chronic pulmonary regurgitation (PR). Two-dimensional echocardiography suboptimally correlate with RV volumes. This study tested whether combination of guideline-directed RV measures in a machine learning (ML) framework improves quantitative assessment of RVEDV and RVEF. RV measurements were obtained on subjects with > mild PR who had cMRI and echocardiogram within 90 days. A gradient-boosted trees algorithm predicted cMRI RV dilation (RVEDV > 160 ml/m2) and RV dysfunction (RVEF<47%), first with "guideline-only" measures, and then with "expanded-features" to include 44 total echocardiographic, clinical, and demographic variables. Model performance was compared to clinician visual assessment. Of 232 studies (56% tetralogy of Fallot, 20% pulmonary stenosis), the median age was 21.5 years, 21 (9%) had RV dilation, and 42 (18%) had RV dysfunction. For RV dilation prediction, the guideline-only model area under the receiver operating characteristic (AUROC)=0.68, and expanded-features model AUROC=0.85. At 90% sensitivity, the expanded-features model had 73% specificity, 25% positive predictive value (PPV), and 99% negative predictive value (NPV) This was similar to clinician performance (sensitivity 81%, specificity 81%, PPV 29%, NPV 98%). For prediction of RV dysfunction, the guideline-only AUROC= 0.71, additional features did not improve the model, and clinicians outperformed the model. In patients with PR, a ML model combining guidelines for RV assessment with demographic and additional echocardiographic parameters may effectively rule-out those with significant RV dilation at clinical thresholds for intervention, and performs similarly to expert clinicians.

Guidelines for the Echocardiographic Assessment of the Right Heart in Adults and Special Considerations in Pulmonary Hypertension: Recommendations from the American Society of Echocardiography

Right heart adaptation to pulmonary hypertension (PH) is a critical determinant of clinical outcomes, morbidity, and mortality in patients with or at risk for cardiopulmonary disease. The World Symposium on Pulmonary Hypertension recently redefined PH as a mean pulmonary arterial pressure >20 mm Hg, based on a wealth of epidemiologic evidence underscoring the significant impact of even mildly elevated mean pulmonary artery pressures on major adverse clinical events. The lowered diagnostic threshold for PH has renewed interest in echocardiography and its critical role in early detection and screening, refined hemodynamic evaluation, and longitudinal monitoring. However, the systematic assessment of the right heart remains inconsistent, largely due to the predominant focus on left heart evaluation, limited familiarity with right heart ultrasound techniques, and a paucity of reference data defining normal right heart size and function. A systematic, comprehensive ultrasound-based assessment of the right heart offers valuable diagnostic insights for in screening at-risk populations, PH classification, risk stratification, monitoring therapeutic response, and informing prognostication, thereby improving clinical outcomes.

Association Between Location of Pulmonary Outflow Obstruction and Right Ventricular Size and Function After Repair of Tetralogy of Fallot, Pulmonary Atresia, and Major Aortopulmonary Collaterals

Quantification of right ventricular (RV) size and function after tetralogy of Fallot repair is critical for determining timing of reintervention and outcomes. Tetralogy of Fallot patients with pulmonary atresia and major aortopulmonary collateral arteries (TOF/PA/MAPCAs) are a unique group in which the RV is subjected to various loading conditions, allowing for direct comparison. Retrospective evaluation of RV echocardiographic indices in repaired pediatric TOF/PA/MAPCAs patients (2/2002 - 4/2018). Patients were categorized as having conduit stenosis (peak gradient ≥ 2.5 m/s) and/or distal pulmonary artery (PA) stenoses (requiring catheter or surgical intervention and > 1/2 systemic RV pressures). A comparison group (N = 9) included distinct age-matched repaired patients without residual lesions. Indexed right heart dimensions were larger in patients with distal PA stenoses (N = 49) compared to conduit stenosis (N = 26), including RV end-diastolic and end-systolic dimensions (p < 0.01), despite earlier time to reintervention (p < 0.0001). RV fractional area change (FAC) was diminished in patients with distal PA stenoses compared to patients without residual lesions (p = 0.006). Patients with conduit stenosis demonstrated a marked decrement in tricuspid annular plane systolic excursion (TAPSE) z-scores. Repaired TOF/PA/MAPCAs patients with residual distal PA stenoses have larger right heart dimensions compared to patients with conduit stenosis, and decreased RV FAC compared to patients without residual lesions at 1-2 years after repair, suggesting early surveillance and immediate intervention on stenotic PA segments appears warranted to decrease the risk of further deterioration of RV systolic function.

Speckle-Tracking Echocardiography in Right Ventricular Function of Clinically Well Patients with Heart Transplantation

Heart transplantation (HT) is the mainstream therapy for end-stage heart disease. However, the cardiac graft function can be affected by several factors. It is important to monitor HT patients for signs of graft dysfunction. Transthoracic echocardiography is a simple, first-line, and non-invasive method for the assessment of cardiac function. The emerging speckle-tracking echocardiography (STE) could quickly and easily provide additive information over traditional echocardiography. STE longitudinal deformation parameters are markers of early impairment of ventricular function. Although once called the "forgotten ventricle", right ventricular (RV) assessment has gained attention in recent years. This review highlights the potentially favorable role of STE in assessing RV systolic function in clinically well HT patients.

Repaired Tetralogy of Fallot: Have We Understood the Right Timing of PVR?

Despite many advances in surgical repair during the past few decades, the majority of tetralogy of Fallot patients continue to experience residual hemodynamic and electrophysiological abnormalities. The actual issue, which has yet to be solved, is understanding how this disease evolves in each individual patient and, as a result, who is truly at risk of sudden death, as well as the proper timing of pulmonary valve replacement (PVR). Our responsibility should be to select the most appropriate time for each patient, going above and beyond imaging criteria used up to now to make such a clinically crucial decision. Despite several studies on timing, indications, procedures, and outcomes of PVR, there is still much uncertainty about whether PVR reduces arrhythmia burden or improves survival in these patients and how to appropriately manage this population. This review summarizes the most recent research on the evolution of repaired tetralogy of Fallot (from adolescence onwards) and risk factor variables that may favor or delay PVR.

Comparison of advanced echocardiographic right ventricular functional parameters with cardiovascular magnetic resonance in adult congenital heart disease

Aims

Advanced transthoracic echocardiography (TTE) using volumetric and deformational indices provides detailed quantification of right ventricular (RV) function in adults with congenital heart disease (ACHD). Two-dimensional multi-plane echocardiography (2D-MPE) has demonstrated regional wall differences in RV longitudinal strain (LS). This study aims to evaluate the association of these parameters with cardiovascular magnetic resonance (CMR).

Methods and results

One-hundred stable ACHD patients with primarily affected RVs were included (age 50 ± 5 years; 53% male). Conventional and advanced echocardiographic RV functional parameters were compared with CMR-derived RV function. Advanced echocardiographic RV functional parameters were measurable in approximately one-half of the study cohort, while multi-wall LS assessment feasibility was lower. CMR RV ejection fraction (CMR-RVEF) was moderately correlated with deformational, area, and volumetric parameters [RV global LS (lateral wall and septum), n = 55: r = -0.62, P < 0.001; RV wall average LS, n = 34: r = -0.49, P = 0.002; RV lateral wall LS, n = 56: r = -0.45, P < 0.001; fractional area change, n = 67: r = 0.48, P < 0.001; 3D-RVEF, n = 48: r = 0.40, P = 0.005]. Conventional measurements such as TAPSE and RV S' correlated poorly. RV global LS best identified CMR-RVEF < 45% (area under the curve: 0.84, P < 0.001: cut-off value -19%: sensitivity 100%, specificity 57%). RVEF and LS values were significantly higher when measured by CMR compared with TTE (mean difference RVEF: 5 [-9 to 18] %; lateral (free) wall LS: -7 [7 to -21] %; RV global LS: -6 [5 to -16] %) while there was no association between respective LS values.

Conclusion

In ACHD patients, advanced echocardiographic RV functional parameters are moderately correlated with CMR-RVEF, although significant differences exist between indices measurable by both modalities.

Right Ventricular Strain in Patients With Ductal-Dependent Tetralogy of Fallot

BACKGROUND

Right ventricular (RV) dysfunction is an independent predictor of poor outcomes in patients with tetralogy of Fallot (TOF), and global longitudinal strain (GLS) is a well-validated echocardiographic technique to measure RV function. Although trends in RV GLS have been examined in patients with TOF, they have not been studied specifically in those with ductal-dependent TOF, a group in which there is not a clear consensus on the best surgical strategy. The aim of this study was to assess the midterm trajectory of RV GLS in patients with ductal-dependent TOF, drivers of this trajectory, and differences in RV GLS between repair strategies.

METHODS

This was a retrospective two-center cohort study of patients with ductal-dependent TOF who underwent repair. Ductal dependence was defined as being initiated on prostaglandin therapy and/or undergoing surgical intervention on or before 30 days of life. RV GLS was measured on echocardiography preoperatively, early after complete repair, and at 1 and 2 years of age. RV GLS was trended over time and compared between surgical strategies and with control subjects. Mixed-effects linear regression models were used to evaluate the factors associated with changes in RV GLS over time.

RESULTS

Forty-four patients with ductal-dependent TOF were included in the study, of whom 33 (75%) underwent primary complete repair and 11 (25%) underwent staged repair. Complete TOF repair was performed at a median of 7 days in the primary-repair group and 178 days in the staged-repair group. RV GLS improved over time from post-complete repair echocardiography through 2 years of age (-17.4% [interquartile range, -15.5% to -18.9%] vs -21.5% [interquartile range, -18.0% to -23.3%], P < .001). However, compared with age-matched control subjects, patients had worse RV GLS at all time points. There was no difference in RV GLS between the staged and primary complete repair groups at 2-year follow-up. Shorter intensive care unit length of stay after complete repair was independently associated with improvement in RV GLS over time. Strain improved by 0.07% (95% CI, 0.01 to 0.12) for each fewer day in the intensive care unit (P = .03).

CONCLUSIONS

RV GLS improves over time among patients with ductal-dependent TOF, though it is consistently reduced compared with control subjects, suggesting an altered deformation pattern in patients with ductal-dependent TOF. There was no difference in RV GLS between the primary- and staged-repair groups at midterm follow-up, suggesting that repair strategy is not a risk factor for worse RV strain in the mid postoperative period. A shorter complete-repair intensive care unit length of stay is associated with an improved trajectory of RV GLS.

Evaluation of right ventricle systolic function after tetralogy of Fallot repair: A systematic review comparing cardiac magnetic resonance and global longitudinal strain

BACKGROUND

Most patients who undergo tetralogy of Fallot (TOF) repair experience late right ventricle (RV) dysfunction due to pulmonary valve regurgitation (PVR). Cardiac magnetic resonance (CMR) is the gold standard method for evaluating RV during follow-up. Global longitudinal strain (GLS) has been introduced as a novel method for the assessment of RV dysfunction. We aimed to compare the feasibility of GLS and CMR for assessing RV function after TOF repair.

METHODS

We systematically reviewed the English literature using PubMed, SciELO and Google Scholar for articles published between January 1, 2015, and December 31, 2020. Articles evaluating RV function comparing by GLS and CMR after TOF repair were included.

RESULTS

Nine studies including 465 patients were analyzed. Most patients were men (280; 60%), the male:female ratio was 1.5:1, and the age range was .8 to 57.7 years. The mean follow-up time was 6 to 32 months. The correlation between RV GLS and RV ejection fraction (EF) by CMR was negative for the articles and varied from moderate to strong (r = -.45, r = -.60, r = -.76).

CONCLUSION

Right ventricle GLS can be considered for routine follow-up of TOF repair patients, even though CMR remains the noninvasive gold standard method. Using a single parameter may not allow comparison of the accuracy of 3D RV EF by using CMR and GLS. Further studies with a larger number of patients undergoing TOF repair are required to evaluate the correlation between these examinations.

[Long-term repaired tetralogy of Fallot : Echocardiographic parameters in correlation with cardiac MRI]

INTRODUCTION

Tetralogy of Fallot (ToF) is the most common cyanotic congenital heart disease. After surgical repair, the excellent survival rate has led to long-term complications dominated by pulmonary regurgitation (PR). Our study aimed to identify echocardiographic criteria for assessment of right ventricular (RV) function and quantification of PR correlated with cardiac MRI indices.

METHODS

We conducted a descriptive study between June 2021 and March 2022 including patients followed for repaired ToF since 2016 or earlier. All patients were seen for clinical, electrocardiographic, and ultrasound evaluation. Cardiac MRI was performed with a maximum delay of 1 month from Doppler echocardiography.

RESULTS

38 patients were included, with a mean age at imaging of 18 ± 9 years. Our study showed that the echocardiographic parameters of PR quantification correlated with a pulmonary regurgitation fraction on MRI greater than 40% were: the PHT value (p = 0.005) and the ratio of PR jet width to pulmonary valve annulus diameter (p = 0.032). The only ultrasound parameter estimating RV systolic function correlated with RVEF on cardiac MRI was FAC, with p = 0.007.

CONCLUSION

Quantitative assessment of RV parameters in patients followed for repaired ToF, as well as the assessment of the severity of PR, is feasible with a standardized ultrasound examination, with good correlation with cardiac MRI.

Superior prognostic value of right ventricular free wall compared to global longitudinal strain in patients with repaired tetralogy of Fallot

Objectives

Both right ventricular free wall longitudinal strain (RVFWLS) and right ventricular global longitudinal strain (RVGLS) using two-dimensional speckle tracking echocardiography (2D-STE) has been demonstrated to predict adverse outcomes in patients with repaired tetralogy of Fallot (r-TOF). However, RVGLS may be affected by left ventricular (LV) function owing to the fact that the interventricular septum is also a part of the left ventricle. Therefore, the aim of our study was to compare the predictive value of RVFWLS with that of RVGLS in patients with r-TOF.

Materials and methods

A total of 179 patients with r-TOF were included in this study. RVFWLS, RVGLS, and left ventricle global longitudinal strain (LVGLS) were evaluated by 2D-STE. The adverse clinical events were death or r-TOF-related rehospitalization. Prognostic performance was evaluated by C-statistic and Akaike information criterion (AIC).

Results

Thirty-one patients developed poor outcomes during a median follow-up period of 2.8 years. Compared with patients without end-point events, those with end-point events had higher incidence of moderate/severe pulmonary regurgitation, larger right heart sizes, and lower RV fractional area change (RVFAC), RVFWLS, RVGLS, and LVGLS than those without. Multivariate Cox regression analysis revealed that RVFAC, RVFWLS, RVGLS, and LVGLS were predictive of poor outcomes in patients with r-TOF after adjustment for transannular patch and QRS duration. A Cox model using RVFWLS (C index = 0.876, AIC = 228) was found to predict unfavorable outcomes more accurately than a model with RVGLS (C index = 0.856, AIC = 243), RVFAC (C index = 0.811, AIC = 248), and LVGLS (C index = 0.830, AIC = 248).

Conclusion

Although both RVGLS and RVFWLS are associated with adverse events, RVFWLS provides superior prognostic value than that of RVGLS in patients with r-TOF.

Multiparametric evaluation of right ventricular function in pulmonary arterial hypertension associated with congenital heart disease

INTRODUCTION AND OBJECTIVES

Outcome in patients with congenital heart diseases and pulmonary arterial hypertension (PAH) is closely related to right ventricular (RV) function. Two-dimensional echocardiographic parameters, such as strain imaging or RV end-systolic remodeling index (RVESRI) have emerged to quantify RV function.

METHODS

We prospectively studied 30 patients aged 48±12 years with pretricuspid shunt and PAH and investigated the accuracy of multiple echocardiographic parameters of RV function (tricuspid annular plane systolic excursion, tricuspid annular peak systolic velocity, RV systolic-to-diastolic duration ratio, right atrial area, RV fractional area change, RV global longitudinal strain and RVESRI) to RV ejection fraction measured by cardiac magnetic resonance.

RESULTS

RV ejection fraction <45% was observed in 13 patients (43.3%). RV global longitudinal strain (ρ [Spearman's correlation coefficient]=-0.75; P=.001; R²=0.58; P=.001), right atrium area (ρ=-0.74; P <.0001; R²=0.56; P <.0001), RVESRI (ρ=-0.64; P <.0001; R²=0.47; P <.0001), systolic-to-diastolic duration ratio (ρ=-0.62; P=.0004; R²=0.47; P <.0001) and RV fractional area change (ρ=0.48; P=.01; R²=0.37; P <.0001) were correlated with RV ejection fraction. RV global longitudinal strain, RVESRI and right atrium area predicted RV ejection fraction <45% with the greatest area under curve (0.88; 95%CI, 0.71-1.00; 0.88; 95%CI, 0.76-1.00, and 0.89; 95%CI, 0.77-1.00, respectively). RV global longitudinal strain >-16%, RVESRI ≥ 1.7 and right atrial area ≥ 22 cm² predicted RV ejection fraction <45% with a sensitivity and specificity of 87.5% and 85.7%; 76.9% and 88.3%; 92.3% and 82.4%, respectively.

CONCLUSIONS

RVESRI, right atrial area and RV global longitudinal strain are strong markers of RV dysfunction in patients with pretricuspid shunt and PAH.

The Interplay between Myocardial Fibrosis, Strain Imaging and Collagen Biomarkers in Adults with Repaired Tetralogy of Fallot

Background: We sought to assess the interplay between right ventricle (RV) fibrosis, biventricular dysfunction based on global longitudinal strain (GLS) analysis, and biomarkers such as Galectin-3 (Gal-3), procollagen type III (PCIII), and NTproBNP. Methods: We studied 35 adult patients with rToF. All patients underwent a cardiac magnetic resonance (CMR) scan including feature tracking for deformation imaging. Blood biomarkers were measured. Results: LGE RV was detected in all patients, mainly at surgical sites. Patients with the highest RV LGE scoring had greater RV dilatation and dysfunction whereas left ventricular (LV) function was preserved. LV GLS correlated with RV total fibrosis score (p = 0.007). A LV GLS value of −15.9% predicted LGE RV score > 8 (AUC 0.754 (p = 0.02)). Neither RV GLS nor biomarker levels were correlated with the extent of RV fibrosis. A cut-off value for NTproBNP of 145.25 pg/mL predicted LGE RV score > 8 points (AUC 0.729, (p = 0.03)). A cut-off value for Gal-3 of 7.42 ng/mL predicted PR Fraction > 20% [AUC 0.704, (p = 0.05)]. Conclusions: A significant extent of RV fibrosis was mainly detected at surgical sites of RV, affecting RV performance. CMR-FT reveals subtle LV dysfunction in rToF patients, due to decreased performance of the fibrotic RV. Impaired LV function and elevated NTproBNP in rToF reflect a dysfunctional fibrotic RV.

Multi-plane echocardiographic assessment of right ventricular function in adults with repaired Tetralogy of Fallot

In patients with repaired Tetralogy of Fallot (ToF), detailed assessment of right ventricular (RV) function is important for management and timing of possible pulmonary valve re-intervention. The aim of this study was to evaluate RV function using two-dimensional multi-plane echocardiography (2D MPE), a novel four-wall imaging method obtained from one apical acoustic window utilising electronic plane rotation. In sixty-two ToF patients (aged - 28 [22, 39] years, 65% male), systolic function of four different RV walls (lateral, anterior, inferior and inferior coronal) were evaluated using MPE. Tricuspid annular plane systolic excursion (TAPSE), tricuspid annular peak systolic velocity (RV-S′) and RV wall longitudinal strain (RV-LS) measurements were compared with those of matched healthy individuals. 2D MPE measurements were highly feasible across the four RV walls (93.5–100% for TAPSE/S′; 66.1–95.1% for RVLS) and could be performed more reliably than 3D RV ejection fraction (RVEF − 56.5%). All functional values were significantly reduced when compared to the control group (p < 0.001). Higher RV-LS values were seen in the lateral (− 17.8 ± 4.5%) and inferior (− 17.8 ± 4.2%) walls compared to the anterior (− 15.9 ± 3.8%) and inferior coronal (− 15.1 ± 3.9%) walls. 3D RVEF correlated strongest with RV-LS values from the lateral (r − 0.50; p = 0.002) and anterior walls (r − 0.74; p < 0.001) and furthermore the four-wall average (r − 0.57; p = 0.001). 2D MPE evaluation of the RV is highly feasible in ToF patients. This novel method provides new insights into regional RV wall function, enabling a more comprehensive and quantitative approach to RV assessment in daily clinical practice.

The Association Between Notching of the Right Ventricular Outflow Tract Flow Velocity Doppler Envelope and Impaired Right Ventricular Function After Acute High-Altitude Exposure

Introduction

Pulmonary artery pressure (PAP) is increased and right ventricular (RV) function is well preserved in healthy subjects upon exposure to high altitude (HA). An increase in PAP may trigger notching of the right ventricular outflow tract Doppler flow velocity envelope (RVOT notch), which is associated with impaired RV function in patients with pulmonary hypertension. However, whether HA exposure can induce RVOT notch formation and the subsequent impact on cardiac function in healthy subjects remains unclear.

Methods

A total of 99 subjects (69 males and 30 females) with a median age of 25 years were enrolled in this study; they traveled from 500 to 4100 m by bus over a 2-day period. All subjects underwent a comprehensive physiological and echocardiographic examination 1 day before ascension at low altitude and 15 ± 3 h after arrival at HA. The RVOT notch was determined by the presence of a notched shape in the RVOT Doppler flow velocity envelope. The systolic PAP (SPAP) was calculated as Bernoulli equation SPAP = 4 × (maximum tricuspid regurgitation velocity)²+5 and mean PAP (mPAP) = 0.61 × SPAP+2. Cardiac output was calculated as stroke volume × heart rate. Pulmonary capillary wedge pressure (PCWP) was calculated as 1.9+1.24 × mitral E/e’. Pulmonary vascular resistance (PVR) was calculated as (mPAP-PCWP)/CO.

Results

After HA exposure, 20 (20.2%) subjects had an RVOT notch [notch (+)], and 79 (79.8%) subjects did not have an RVOT notch [notch (−)]. In the multivariate logistic regression analysis, the SPAP, right ventricular global longitude strain (RV GLS), and tricuspid E/A were independently associated with the RVOT notch. The SPAP, mPAP, PVR, standard deviations of the times to peak systolic strain in the four mid-basal RV segments (RVSD4), peak velocity of the isovolumic contraction period (ICV), and the peak systolic velocity (s’) at the mitral/tricuspid annulus were increased in all subjects. Conversely, the pulse oxygen saturation (SpO₂), RV GLS, and tricuspid annulus plane systolic excursion (TAPSE)/SPAP were decreased. However, the increases of SPAP, mPAP, PVR, and RVSD4 and the decreases of SpO₂, RV GLS, and TAPSE/SPAP were more pronounced in the notch (+) group than in the notch (−) group. Additionally, increased tricuspid ICV and mitral/tricuspid s’ were found only in the notch (−) group.

Conclusion

HA exposure-induced RVOT notch formation is associated with impaired RV function, including no increase in the tricuspid ICV or s’, reduction of RV deformation, deterioration in RV-pulmonary artery coupling, and RV intraventricular synchrony.