Age- and Sex-Specific MR-Feature Tracking Reference Values of Right Atrial Deformation in Healthy Adults.

BACKGROUND: Although right atrial (RA) myocardial deformation has important implications for patient diagnosis, prognosis, and risk stratification, its implementation in clinical practice has been hampered by limited normal reference values, especially in Asian populations. PURPOSE: To establish age- and sex-specific reference values for RA strain, strain rate (SR), and displacement based on a large sample of healthy Chinese adults using MR-feature tracking (MR-FT). STUDY TYPE: Retrospective. POPULATION: 524 healthy Chinese adults (287 male; mean age 43.7 ± 11.9 years). FIELD STRENGTH/SEQUENCE: 1.5T/balanced steady-state free precession. ASSESSMENT: RA deformation parameters, including reservoir, conduit, and booster strain (εs, εe, and εa), peak positive, early negative, and late negative SR (SRs, SRe, and SRa), and total, passive, and active displacement (Ds, De, and Da), were assessed using MR-FT. STATISTICAL TESTS: Student's t-test, one-way ANOVA, coefficients of determination (r2 ), intraclass correlation coefficients (ICC), and Bland-Altman plots. A P value <0.05 was considered significant. RESULTS: Women demonstrated significantly greater magnitudes of RA deformation parameters than men: εs (57.4% ± 15.1% vs. 44.3% ± 12.6%), εe (37.5% ± 13.4% vs. 27.4% ± 10.9%), εa (19.9% ± 5.7% vs. 16.9% ± 5.0%), SRs (2.62 ± 0.88 sec-1 vs. 2.00 ± 0.63 sec-1 ), SRe (-2.98 ± 1.26 sec-1 vs. -2.16 ± 0.92 sec-1 ), SRa (-2.28 ± 0.75 sec-1 vs. -1.84 ± 0.62 sec-1 ), Ds (-7.80 ± 1.90 mm vs. -7.46 ± 1.70 mm), and De (-4.84 ± 1.31 mm vs. -4.49 ± 1.21 mm). For both sexes, aging was significantly associated with decreased RA reservoir and conduit function (εs, SRs, Ds, εe, SRe, and De), and with increased εa and Da. RA deformation measurements had good to excellent intraobserver and interobserver reproducibility, with ICCs ranging from to 0.790 to 0.972. DATA CONCLUSION: This study provides age- and sex-specific reference values of RA strain, SR, and displacement based on a large cohort of healthy Chinese adults using MR-FT. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Prognostic value of right atrial strain in systemic sclerosis based on tissue tracking analysis using cine cardiac magnetic resonance imaging: a retrospective observational study.

Interstitial lung disease and cardiac involvement are common manifestations and prognostic factors of systemic sclerosis. However, it is unclear whether impaired right atrial function associated with interstitial lung disease in systemic sclerosis can be used as a prognostic factor in this patient population. Therefore, this study aimed to investigate the relationship between right atrial function, interstitial lung disease, and prognosis in patients with systemic sclerosis using tissue tracking analysis with cine cardiac magnetic resonance imaging. In this retrospective observational study, a total of 40 patients with systemic sclerosis were enrolled. Tissue tracking analysis was used to obtain time curves of right atrial strain. Reservoir (total strain), conduit (passive strain), and booster (active strain) pump function were calculated, and right atrial strain, interstitial lung disease, and clinical outcomes were examined. An adverse clinical event was defined as all-cause death. Overall, 23 patients had interstitial lung disease (58%). Six patients died during the follow-up (median, 44 months). The total skin score and right ventricular systolic pressure on echocardiography were higher in patients with an event than in those without an event (28 ± 16% vs. 13 ± 13%, P = 0.02; 46.3 ± 10.7 mmHg vs. 36.0 ± 8.5 mmHg, P = 0.01, respectively). Further, right atrial total strain and active strain were significantly lower in patients with an event than in those without an event (14.3 ± 11.3% vs. 25.8 ± 11.4%, P = 0.03; 3.48 ± 2.37 vs. 11.7 ± 6.78, P = 0.007, respectively). Multivariate analysis revealed that active strain was an independent predictor of all-cause death (hazard ratio 0.76, P = 0.029). Kaplan-Meier analysis revealed that the survival rate was significantly higher in patients with right atrial active strain levels above the cutoff 7.4 (P < 0.05). In systemic sclerosis, right atrial booster function was predictive of mortality. Hence, right atrial functional assessment may have incremental prognostic value for patients with systemic sclerosis, leading to better risk stratification.

Atrial function in paroxysmal AF patients with and without heart failure with preserved ejection fraction: Data from the AF-RISK study.

Atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF) are 2 cardiovascular conditions that often coexist. Strain phases of both the left and right atria are more impaired in paroxysmal AF patients with HFpEF than those without HFpEF in spite of comparable global longitudinal strain of the left ventricle. Atrial function may differentiate paroxysmal AF patients with HFpEF from those without HFpEF.

Assessment of right atrium dysfunction in patients with obstructive sleep apnea syndrome using velocity vector imaging.

BACKGROUND AND OBJECTIVES: This study aimed to assess the changes of RA function in patients with obstructive sleep apnea syndrome (OSAS) using velocity vector imaging (VVI) and to evaluate the application of VVI technology. METHODS: According to the apnea-hypopnea index (AHI), 71 patients with OSAS were divided into three groups: mild, moderate, and severe. A total of 30 cases of healthy subjects were enrolled as the control group. Digital images of apex four-chamber views were acquired to measure the right atrium (RA) linear dimensions and volume parameters including RA longitudinal diameter (RAL), transverse diameter (RAT), RA maximum volume (Vmax), RA minimum volume (Vmin), right atrial volume before contraction (Vpre). Right atrial volume parameters were corrected by body surface area (VImax, VImin, VIpre). The total right atrial emptying fraction (RATEF), right atrial passive emptying fraction (RAPEF), right atrial active contraction emptying fraction (RAAEF) were calculated. The VVI data measuring right atrial global strain (RA-GLS), right atrial strain rate in ventricular systolic phase (RA-SRs), right atrial strain rate in ventricular early diastolic phase (RA-SRe), right atrial strain rate in ventricular late diastolic phase (RA-SRa). RESULTS: 1. RA linear dimensions and volume parameters in severe OSAS were higher than those of control group. RAPEF in severe group was lower than control group and mild OSAS group (t = 2.681, P = 0.021; t = 2.985, P = 0.011; respectively). RAAEF in OSAS moderate group was higher than that of control group (t = 3.006, P = 0.02), and without statistical difference (P > 0.05) in the severe OSAS group and the control group. 2. RA-GLS in moderate OSAS group was significantly lower than that of control group (t = 2.333, P = 0.040) and reduced more obvious in the severe OSAS group (vs control, t = 3.25, P = 0.008, vs mild; t = 3.011, P = 0.012; respectively). RA-SRe in moderate and severe OSAS groups were lower than control group (t = 2.466, P = 0.031; t = 3.547, P = 0.005; respectively). RA-SRs of OSAS in severe group was lower than that of control and mild groups (t = 3.665, P = 0.004; t = 3.204, P = 0.008; respectively). RA-SRa in severe OSAS group was lower than that of control group (t = 2.425, P = 0.034). 3. Multivariate regression analysis showed that RA-GLS and RA-SRe were independently correlated with AHI (t = - 2.738, P = 0.010; t = - 2.191, P = 0.036; respectively). CONCLUSION: RA function was impaired in patients with OSAS. On hemodynamics, the change of RA function performed increased of reserve function, reduced pipeline function and increased of contraction function. However, the strain and strain rate reduced in different degree. RA-GLS and RA-SRe decreased the earliest, which suggested that strain and strain rate were the parameters which can reflect myocardial function damage earliest. VVI can more earlier and accurately detect myocardial dysfunction of right atrium in patients with OSAS, which is expected to be a worthy technique for early clinical therapy in patients with OSAS.

Three-dimensional echocardiography to evaluate right atrial volume and phasic function in pulmonary hypertension.

OBJECTIVE: Pulmonary hypertension (PH) impairs right ventricular (RV) systolic and diastolic function, which in turn induces compensatory changes in right atrial (RA) function; the diverse effects on RA function are subject to much debate. We hypothesized that RA function plays a more important role in compensating RV dysfunction, than mere prevention of clinical failure in patients with PH. METHODS: We studied 54 patients with PH and 23 healthy controls. RA volume, including maximum RA volume, minimum RA volume, and the volume before atrial systole, was evaluated by 3DE. RA maximum volume index (Vmax I), total emptying volume index (TotEVI), passive emptying volume index (PassEVI), and active ejection fraction (ActEF) were calculated. Receiver operating characteristic curve analysis was used to determine the sensitivity and specificity of various cutoff levels of the variables measured for predicting World Health Organization functional class (WHO-FC) IV in patients with PH. RESULTS: RAVmax I in patients with PH was higher than that in controls. In patients with PH, the TotEVI was significantly higher, while PassEVI was significantly lower as compared to that in controls. ActEF was increased in patients with WHO functional class (WHO-FC) III PH as compared to that in controls (P = .003) but was reduced in more advanced cases (WHO-FC IV). In addition, the area under the curve of 3D RA ActEF was larger than those of 2D RA ActEF, RA GLS, RA area, FAC, TAPSE, and RIMP (P < .01 for all) for predicting WHO-FC IV. CONCLUSION: We demonstrated that RA function plays a more important role in compensating RV dysfunction then mere prevention of clinical failure in PH.

Right heart function in impaired left ventricular diastolic function: 2D speckle tracking echocardiography-based and Doppler tissue imaging-based analysis of right atrial and ventricular function.

AIM: The aim of our study was to describe right atrial (RA) and right ventricular (RV) function, assessed by Doppler tissue imaging and 2D speckle tracking echocardiography (2DSTE), in women with signs of early impaired left ventricular diastolic function (DD). METHODS AND RESULTS: In a cross-sectional trial, standard parameters of diastolic and right heart function were investigated in 438 women of the Berlin Female Risk Evaluation (BEFRI) study. In a subset of women, average peak systolic RA strain (RAS), as well as the average peak systolic RV strain of the free wall (RVS free wall) and of all RV segments (average RV strain; RVS Avg), was analyzed using 2DSTE. Compared to women with normal diastolic function (DD0), RAS, RVS free wall and RVS Avg were significantly reduced in DD (43.1% ± 11.9%, -26.7% ± 5.6%, and -23.3% ± 3.5% in DD0; vs 35.1% ± 10.4%, -23.9% ± 5.5%, and -20.6% ± 3.8% in DD; P < .01). Peak RV myocardial velocity (RV-IVV) and acceleration during isovolumetric contraction (RV-IVA) were markedly higher in DD (15.0 ± 3.9 cm/s and 3.1 ± 1.0 m/s² in DD vs 11.9 ± 3.2 cm/s and 2.8 ± 0.8 m/s² in DD0; P < .05). RAS and RV-IVV were significantly associated with DD after adjustment to age, BMI, and left atrial strain in multivariate regression analysis. CONCLUSION: Systolic right heart function is significantly altered in DD. DTI as well as 2DSTE constitute sensitive echocardiographic tools that enable the diagnosis of impaired right heart mechanics in early-staged DD.

Right Atrial Evaluation in Patients With Pulmonary Hypertension: A Real-time 3-Dimensional Transthoracic Echocardiographic Study.

OBJECTIVES: The purpose of this study was to investigate the changes in the morphologic characteristics and performance of the right atrium (RA) that occur secondary to structural remodeling of the right ventricle (RV) in patients with pulmonary hypertension by real-time 3-dimensional echocardiography (3DE). METHODS: Comprehensive 2-dimensional echocardiography and real-time 3DE were performed in 112 patients and 30 healthy control participants. Patients with pulmonary hypertension were divided into 3 subgroups: 1, normal RV dimension (n = 34); 2, RV enlargement and preserved systolic function (n = 36); and 3, RV enlargement and systolic dysfunction (n = 42). RESULTS: Patients had larger RA volume parameters and lower RA passive emptying fractions than controls (P< .01). The RA active emptying fraction was higher in patient groups 1 (mean ± SD, 45.5% ± 10.7%) and 2 (40.1% ± 4.0%) and lower in group 3 (19.3% ± 4.3%) compared to controls (35.4% ± 3.5%). The RA total emptying fraction was similar between groups 1 and 2 (59.3% ± 9.7% and 52.6% ± 3.4%, respectively) but was significantly lower in group 3 compared to controls (26.8% ± 5.1% versus 55.2% ± 5.1%). Right atrial volume and phasic function were substantially affected by RV structure and function. CONCLUSIONS: Real-time 3DE is a feasible, repeatable, and noninvasive method for accessing cyclic RA volume and function changes, such as those that occur with varying RV status in patients with pulmonary hypertension.

Prognostic value of right atrial function in patients with significant tricuspid regurgitation.

AIMS: Although right ventricular (RV) dysfunction is associated with adverse outcomes in tricuspid regurgitation (TR), the potential role of right atrial (RA) function is unknown. We aimed to investigate the relationship between RA function and clinical outcomes in patients with significant TR. METHODS: This retrospective study included 169 outpatients with moderate or severe TR due to left-sided heart diseases who underwent transthoracic echocardiography between June 2020 and April 2023 (average age, 75 ± 10 years; male, 40%). Patients with atrial fibrillation were excluded from this study due to the inaccuracy of the evaluation using 2D speckle-tracking echocardiography. RA function was compared between patients with and without events, which were defined as all-cause mortality or hospitalization due to heart failure. RA function was calculated as RA global longitudinal strain (RAGLS) with the 2D speckle-tracking echocardiography. RESULTS: During a median follow-up of 13 months, 19 patients had events (all-cause mortality: 14 cases, hospitalization due to heart failure: 5 cases). RAGLS was lower in patients with events than in those without events (13% ± 10% vs. 18% ± 9%, P = 0.02). When the patients were categorized into two groups [low RAGLS ≤ 16.2% vs. high RAGLS > 16.2%, high RA volume index (RAVI) ≥ 50 mL/m2 vs. low RAVI < 50 mL/m2], Kaplan-Meier curves showed that patients with low RAGLS had higher event rates than those with high RAGLS (log-rank test, P = 0.003). Patients with high RAVI had higher event rates than those with low RAVI (log-rank test, P < 0.001). In the multivariate Cox regression analysis, low RAGLS (≤16.2%) was significantly associated with events in a model that included RV dysfunction (RV fractional area change ≤ 35%) or high RAVI (≥50 mL/m2) (hazard ratio: 4.55, 95% confidence interval: 1.51-13.71, P < 0.01; hazard ratio: 4.57, 95% confidence interval: 1.52-13.79, P < 0.01, respectively). CONCLUSIONS: RAGLS is associated with all-cause mortality and hospitalization due to heart failure in patients with significant TR. Our results suggest that RA function is a sensitive marker for identifying the risk stratification of significant TR.

Prognostic value of right atrial strains in arrhythmogenic right ventricular cardiomyopathy.

OBJECTIVES: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy characterized by progressive fibrofatty infiltration of atrial and ventricular myocardium resulting in adverse cardiac events. Atrial function has been increasingly recognized as prognostically important for cardiovascular disease. As the right atrial (RA) strain is a sensitive parameter to describe RA function, we aimed to analyze the prognostic value of the RA strain in ARVC. METHODS: RA strain parameters were derived from cardiac magnetic resonance (CMR) images of 105 participants with definite ARVC. The endpoint was defined as a combination of sudden cardiac death, survival cardiac arrest, and appropriate implantable cardioverter-defibrillator intervention. Cox regression and Kaplan-Meier survival analyses were performed to evaluate the association between RA strain parameters and endpoint. Concordance index (C index), net reclassification index (NRI), and integrated discrimination improvement (IDI) were calculated to assess the incremental value of RA strain in predicting the endpoint. RESULTS: After a median follow-up of 5 years, 36 (34.3%) reaching the endpoint displayed significantly reduced RA strain parameters. At Kaplan-Meier analysis, impaired RA reservoir (RARS) and booster strains (RABS) were associated with an increased risk of the endpoint. After adjusting for conventional risk factors, RARS (hazard ratio [HR], 0.956; p = 0.005) and RABS (HR, 0.906; p = 0.002) resulted as independent predictors for endpoint at Cox regression analyses. In addition, RARS and RABS improved prognostic value to clinical risk factors and CMR morphological and functional predictors (all p < 0.05). CONCLUSION: RARS and RABS were independent predictors for adverse cardiac events, which could provide incremental prognostic value for conventional predictors in ARVC. CRITICAL RELEVANCE STATEMENT: We evaluated the prognostic value of right atrial strain in ARVC patients and suggested cardiologists consider RA strain as a predictive parameter when evaluating the long-term outcome of ARVC patients in order to formulate better clinical therapy. KEY POINTS: • Patients with ARVC had significantly reduced RA strain and strain rates compared with healthy participants. • Participants with lower RA reservoir and booster stains were associated with a significantly higher risk of adverse cardiac events. • RA booster and reservoir strain provide incremental value to conventional parameters.

Clinical utility and prognostic value of right atrial function in severe tricuspid regurgitation: one more piece of the puzzle.

AIMS: The optimal management of severe tricuspid regurgitation (TR) remains controversial. While right ventricular systolic function is an established prognostic marker of outcomes, the potential role of right atrial (RA) function is unknown. This study aimed to describe RA function by 2D speckle-tracking echocardiography (STE) in at least severe TR and to evaluate its potential association with cardiovascular outcomes. METHODS AND RESULTS: Consecutive patients with at least (≥) severe TR (severe, massive, or torrential TR) evaluated in the Heart Valve Clinic following a comprehensive clinical protocol were included. Consecutive control subjects and patients with permanent isolated atrial fibrillation (AF) were included for comparison (control and AF group, respectively). RA function was measured with 2D-STE and two components of RA function were calculated: reservoir (RASr) and contractile (RASct) strain (AutoStrain, Philips Medical Systems the EPIQ system). A combined endpoint of hospital admission due to heart failure (HF) or all-cause mortality was defined. Patients with ≥ severe TR (n = 140) showed lower RASr compared with controls (n = 20) and with the AF group (n = 20) (P < 0.001). Atrial TR showed lower RASr compared with other aetiologies of TR (P < 0.001). After a median follow-up of 2.2 years (IQR: 12-41 months), RASr remained an independent predictor of mortality and HF. A cut-off value of RASr of <9.4% held the best accuracy to predict outcomes. CONCLUSION: RA function by 2D-STE independently predicts mortality and HF hospitalizations in patients with ≥ severe TR.

Right atrial strain and cardiovascular outcome in arrhythmogenic right ventricular cardiomyopathy.

AIMS: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by progressive fibro-fatty infiltration of the myocardium and associated with adverse cardiovascular (CV) events. This study aims to examine right atrial (RA) deformation in ARVC and understand its association with CV outcomes. METHODS AND RESULTS: RA strain was determined in 50 patients with definite ARVC, compared with a matched control group of 50 healthy individuals, and analysed for outcome association over a median follow-up duration of 5 years. A subgroup of 30 ARVC patients with normal RA volume (ARVC-N group) was compared with 30 matched controls (Control-N), and the outcome was analysed separately. RA reservoir, conduit, and pump strain were significantly impaired in ARVC vs. control. Similar observations were made in the N-ARVC subgroup. Reservoir strain was associated with an increased risk of atrial arrhythmia (AA) [hazard ratio (HR) 0.88, P < 0.01] and CV events (HR 0.92, P < 0.01). Conduit strain also predicted AA (HR 1.02, P < 0.01), while pump strain predicted CV events (HR 1.09, P = 0.02). Reservoir strain improved the fitness of bivariable models for the association of RV end-diastolic area index, RV fractional area change, and RV global longitudinal strain with CV events. CONCLUSION: ARVC patients display impaired RA strain even when RA volume is normal. Reservoir and pump strain are associated with an increased risk of CV events. Reservoir strain improved model fitness for the association of RVGLS and other echocardiographic parameters with CV events.

Association between comorbidities and left and right atrial dysfunction in patients with paroxysmal atrial fibrillation: Analysis of AF-RISK.

BACKGROUND: To identify the association between comorbidities and left atrial (LA) and right atrial (RA) function in patients with paroxysmal atrial fibrillation (AF). METHODS: This is a cross-sectional study. Speckle-tracking echocardiography was performed in 344 patients with paroxysmal AF at baseline, and available in 298 patients after 1-year follow-up. The number of comorbidities (hypertension, diabetes mellitus, coronary artery disease, body mass index > 25 kg/m2, age > 65 years, moderate to severe mitral valve regurgitation and kidney dysfunction (estimated glomerular filtration rate < 60 ml/min/1.73 m2)) was determined and the association with atrial strain was tested. RESULTS: Mean age of the patients was 58 (SD 12) years and 137 patients were women (40%). Patients with a higher number of comorbidities had larger LA volumes (p for trend <0.001), and had a decrease in all strain phases from the LA and RA, except for the RA contraction phase (p for trend 0.47). A higher number of comorbidities was associated with LA reservoir and conduit strain decrease independently of LA volume (p < 0.001, p < 0.001 respectively). Patients with 1-2 comorbidities, but not patients with 3 or more comorbidities, showed a further progression of impaired LA and RA function in almost all atrial strain phases at 14 [13-17] months follow-up. CONCLUSIONS: In patients with paroxysmal AF, individual and combined comorbidities are related to lower LA and RA strain. In patients with few comorbidities, impairment in atrial function progresses during one year of follow-up. Whether comorbidity management prevents or reverses decrease in atrial function warrants further study.

Morphological and Dynamic Analysis of the Right Atrioventricular Junction in Healthy Subjects with 4D Computed Tomography.

PURPOSE: To improve knowledge of the tricuspid valve and right atrioventricular junction (RAVJ) coupling, four-dimensional (4D) imaging is mandatory (3D + time). Based on multiphase cardiac-volume computed tomography (CT) and innovative 4D analysis, we proposed to assess dynamical features of tricuspid annulus (TA) in relation to the right ventricle (RV) and right atrial (RA) functions. METHODS: Cardiac-volume CT data sets through time were obtained in 30 healthy patients (Male 57%, mean age 57 ± 11 years). Using an in-house software, 3D semi-automated delineation of 18 points around TA perimeter were defined through 10 cardiac phases within RR interval and used to calculate TA features such as 3D/2D areas, perimeters, 360°-diameters and vertical deformation. RV and RA inner contours were also delineated. Bi-dimensional parameters were compared with multiplanar reconstruction (MPR) measurements. RESULTS: TA was elliptical in horizontal projection with a maximal eccentricity index (EcImax) of 0.58 ± 0.12; and saddle-shaped in vertical projection with a horn nearby the antero-septal commissure. This feature remained throughout the cardiac cycle, but TA was more planar and less circular in late diastole (TA-height: 4.53 ± 1.06 mm, EcImax = 0.61 ± 0.14) when TA 3D area and perimeter reached a maximum of 7.05 ± 1.23 and 7.48 ± 0.93cm/m2, respectively. Correlations between minimal and maximal TA 3D areas and TA Projected 2D areas were excellent (r = 0.993 and r = 0.995, p < 0.001). TA 2D area measurements by MPR overestimated the projected values by 22 to 24%. Correlation between RV concentric strain and TA maximal diameter shortening was r = 0.452 (p = 0.01). CONCLUSIONS: Cardiac-volume CT improves physiological knowledge of the relationships between the RAVJ components in healthy subjects.

Speckle Tracking Imaging in Patients with Pulmonary Hypertension.

BACKGROUND: Right ventricular (RV) systolic dysfunction is a strong predictor of mortality in pulmonary hypertension (PH). The goal of this study was to investigate whether right atrium (RA) and RV myocardial strain related to PH using speckle tracking echocardiography provide a superior estimation of RV systolic function than 2-dimensional (2D)-echo. METHODS: This cross-sectional study analyzed 22 patients with a diagnosis of PH stratified by right heart catheterization, and they were compared to a control group of 22 age- and sex-matched healthy subjects. RESULTS: Global longitudinal peak systolic strain measured in the RV free wall from the apical 4 chamber view was -15% vs. -14.5% when measured from the subcostal view (p = 0.99). Mean longitudinal strain during reservoir phase, and longitudinal strain rate during atrial reservoir and passive conduit function was significantly impaired measured in the right atrial free wall in patients with PH. CONCLUSIONS: This study showed impaired LV contractility in patients with PH assessed by speckle tracking strain. RV free wall longitudinal strain does not correlate with any of the measurements of RV systolic function obtained by 2D echocardiography. A major strength of RV longitudinal strain is its ability to assess the RV function without the limitations of 2D parameters. The subcostal RV strain is a feasible and accurate alternative to conventional RV strain from the apical view in patients with poor acoustic apical 4-chamber windows. The RA strain and strain rates values may be a valuable additive to assess right-sided heart function.

Age- and Sex-Specific Changes in CMR Feature Tracking-Based Right Atrial and Ventricular Functional Parameters in Healthy Asians.

Cardiovascular magnetic resonance (CMR) is the reference standard for non-invasive assessment of right-sided heart function. Recent advances in CMR post-processing facilitate quantification of tricuspid annular (TA) dynamics and longitudinal strains of the right ventricle (RV) and right atrium (RA). We aimed to determine age- and sex-specific changes in CMR-derived TA dynamics, and RV and RA functional parameters in healthy Asian adults. We studied 360 healthy subjects aged 21-79 years, with 30 men and 30 women in each of the six age groups. Functional parameters of RV and RA were measured on standard four-chamber cine CMR using fast feature tracking: (1) TA peak velocities (systolic velocity S', early diastolic velocity E', late diastolic velocity A') and TA plane systolic excursion (TAPSE); (2) RV global longitudinal strain (GLS) and strain rates; and (3) RA phasic longitudinal strains and strain rates. S' and TAPSE exhibited negative correlations with age. RV GLS was significantly higher in females than in males but not associated with age in both sexes. Females had similar E', lower A', and higher E'/A' ratios compared to males. Positive associations of E' and E'/A', and negative association of A' with age were observed in both sexes. Females had higher RA reservoir and conduit strains compared to males. There were significantly negative and positive associations between RA conduit and booster strains, respectively, with age. Age- and sex-specific reference ranges were established, and associations revealed, for fast CMR feature tracking parameters of right heart function in a large normal Asian population.

Balloon pulmonary angioplasty improves right atrial reservoir and conduit functions in chronic thromboembolic pulmonary hypertension.

AIMS: Right atrial (RA) function largely contributes to the maintenance of right ventricular (RV) function. This study investigated the effect of balloon pulmonary angioplasty (BPA) on RA functions in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) using cardiac magnetic resonance imaging (CMRI). METHODS AND RESULTS: CMRI and RV catheterization were performed before BPA sessions and at the follow-up periods in 29 CTEPH patients. Reservoir [RA longitudinal strain (RA-LS)], passive conduit [RA early LS rate (LSR)], and active (RA late LSR) phases were assessed by using cine CMRI and a feature-tracking algorithm. The relationships between the changes in RA functions and in brain natriuretic peptide (BNP) were evaluated in both the dilated and non-dilated RA groups. RA-LS (32.4% vs. 42.7%), RA LSR (6.3% vs. 8.3%), and RA early LSR (-2.3% vs. -4.3%) were improved after BPA, whereas no significant change was seen in RA late LSR. The changes in RA peak LS and in RA early LSR were significantly correlated with the changes in BNP (ΔRA-LS: r = -0.63, ΔRA-early LSR: r = 0.65) and pulmonary vascular resistance (PVR) (ΔRA-LS: r = -0.69, ΔRA-early LSR: r = 0.66) in the nondilated RA group. CONCLUSION: The RA reservoir and passive conduit functions were impaired in inoperable CTEPH, whereas RA active function was preserved. BPA markedly reversed these impaired functions. The improvements in RA reservoir and conduit functions were significantly correlated with the changes in BNP levels and PVR in CTEPH patients with normal RA sizes.

Association of right atrial conduit phase with right ventricular lusitropic function in pulmonary hypertension.

Alterations of right atrial (RA) function have emerged as determinants of outcome in pulmonary hypertension (PH). We aimed to clarify the pathophysiological associations of impaired RA conduit function with right ventricular (RV) function in PH. In 51 patients with PH (48 with pulmonary arterial hypertension), RA conduit function was assessed as echocardiographic peak early diastolic strain rate (PEDSR). PEDSR and cardiac magnetic resonance parameters were measured within 24 h of right heart catheterization and generation of pressure-volume loops to assess RV diastolic (RV end-diastolic pressure [EDP] and relaxation [Tau]) and systolic function. Spearman rho correlation and linear regression analysis were used to determine the association of PEDSR with RV function. The impact of PEDSR on time to clinical worsening was assessed using Kaplan-Meier and Cox regression analyses. Median (interquartile range) PEDSR was - 0.56 s - 1 (- 1.08 to - 0.37). Impaired PEDSR was significantly correlated with RV diastolic stiffness [EDP (rho = 0.570; p < 0.001) and Tau (rho = 0.500; p < 0.001)] but not with RV contractility or coupling. In multivariate linear regression including parameters of RV lusitropic and inotropic function, EDP remained independently associated with impaired PEDSR. During a median follow-up of 9 months, 23 patients deteriorated. After multivariate adjustment, PEDSR remained associated with clinical worsening (hazard ratio: 2.85; 95% confidence interval: 1.20-6.78). Altered RV lusitropy is associated with impaired RA conduit phase. PEDSR emerged as a promising, non-invasive, bedside-ready parameter to evaluate RV diastolic function and to predict prognosis in PH.

Comprehensive Noninvasive Evaluation of Right Ventricle-Pulmonary Circulation Axis in Pediatric Patients with Pulmonary Hypertension.

PURPOSE OF REVIEW: The purpose of this review is to detail the advanced echocardiographic studies that evaluated outcomes in pediatric PH using these advanced imaging techniques: (1) right heart size and function (using 2D and 3D echocardiography), (2) myocardial mechanics, and (3) right ventricular (RV) to pulmonary arterial coupling. RECENT FINDINGS: Advanced echocardiographic imaging tools in pediatric PH include RV/left ventricular ratio, 3D echocardiographic assessment of RV volumes and ejection fraction, right atrial and RV strain, and RV-pulmonary arterial coupling ratio that allow for evaluation of clinical outcomes in this patient population. The right atrial to RV axis provides insights to RV diastolic function that has been poorly understood in pediatrics. The RV-pulmonary arterial coupling ratio helps us understand the mechanics of the RV response to afterload. The advanced imaging tools provide clinical outcome evaluation in pediatric PH patients and provide insight into the RA-RV axis and the RV-pulmonary circulatory unit.

Right atrial function in patients with pulmonary hypertension: A study with two-dimensional speckle-tracking echocardiography.

BACKGROUND: The role of right atrial (RA) dysfunction in patients with pulmonary hypertension (PH), as evaluated by two-dimensional speckle-tracking echocardiography (2D-STE) remains to be determined. METHODS: Sixty consecutive PH patients and 30 healthy volunteers were included. RA function was evaluated by 2D-STE, and the following parameters were recorded: an average longitudinal strain (LS) curve that included LSpos during RA filling and LSneg representing RA active contraction (their summation is LStot), the phasic RA volumes, total RA emptying fraction, and the ratio of RA passive and active emptying to total emptying. The associations between these indices and the results of invasive pulmonary hemodynamics, cardiac structure and function, and NT-terminal pro brain natriuretic peptide (NT-proBNP) level were evaluated. RESULTS: LStot, total RA emptying fraction, LSpos, passive RA emptying fraction were significantly lower, while the contribution of active RA empting fraction/total RA emptying fraction was higher in PH patients than in controls. Among PH patients, LStot was negatively correlated with greater RA size, RA pressure, and pulmonary vascular resistance, but not pulmonary artery pressure, while LStot was also negatively associated with right ventricular enlargement and higher NT-proBNP. In receiver-operator characteristic analysis, RA LStot was of optimal accuracy for prediction of WHO-function class ≥III in PH patients. CONCLUSIONS: PH was associated with impaired reservoir and conduit function, but enhanced active contract function of RA, while RA LStot confers an optimal predictive effect of poor WHO-function class in PH patients.

Right Atrial Function Predicts Clinical Outcome in Patients with Precapillary Pulmonary Hypertension.

BACKGROUND: Although the primary role of right atrial (RA) size in the diagnosis and risk stratification of precapillary pulmonary hypertension (PH) has been studied, little is known about the clinical significance of RA function. In line with studies assessing left atrial function in heart failure, the aim of this study was to introduce the RA function index (RAFi) and to explore its prognostic power in precapillary PH. METHODS: RA emptying fraction was calculated as (RA end-systolic volume - RA end-diastolic volume) × 100/(RA end-systolic volume). RAFi was calculated as (RA emptying fraction × right ventricular outflow tract velocity-time integral)/(RA end-systolic volume index). Patients were followed for the end point of clinical failure, which was defined as death, hospitalization because of PH, or disease progression. RESULTS: In total, 47 patients with precapillary PH were included. Mean RAFi was 16.1 ± 22.3%. Over a median follow-up period of 25 months (interquartile range, 9.5-41.1 months), 29 patients experienced clinical failure. Univariate Cox proportional-hazard analysis showed that RAFi was a predictor of clinical failure (hazard ratio, 0.935; 95% CI, 0.890-0.981; P = .007). Addition of RAFi to established predictors of outcomes, including 6-minute walk distance, N-terminal pro-B-type natriuretic peptide, and RA area, improved their prognostic power. CONCLUSIONS: RAFi is an easily assessed echocardiographic parameter, which is strongly predictive of clinical outcomes in patients with precapillary PH. Further studies are needed to validate RAFi and define its role in clinical practice.