Right Ventricular Strain Measurements Research Articles

Defining Biventricular Abnormalities by Cardiac Magnetic Resonance in Pre-Dialysis Patients with Chronic Kidney Disease.

The aim of the study was to investigate biventricular structural and functional abnormalities in pre-dialysis patients across stages of chronic kidney disease (CKD) by cardiac magnetic resonance (CMR). Fifty-one CKD patients with CMR exams were retrospectively analyzed. Patients were divided into three groups according to estimated glomerular filtration rate (eGFR): CKD 1 group (patients with normal eGFR≥90 mL/min/1.73 m2, n = 20), CKD 2-3 group (patients with eGFR< 90 to ≥30 mL/min/1.73 m2, n = 14), and CKD 4-5 group (patients with eGFR<30 mL/min/1.73 m2, n = 17). Twenty-one age- and sex-matched healthy controls (HC) were recruited. CMR-derived left ventricular (LV) and right ventricular (RV) structural and functional measures were compared. Association between CMR parameters and clinical measures was assessed. There was an increasing trend in RV mass index (RVMi) and LV mass index (LVMi) with the occurrence and development of CKD from HC group to CKD 4-5 group although no significant difference was observed between CKD 1 group and HC group. LV global radial strain and LV global circumferential strain dropped and native T1 value elevated significantly in CKD 4-5 group compared with the other three groups (all p < 0.05), while RV strain measures, RV ejection fraction, and LV ejection fraction showed no significant difference among 4 groups (all p > 0.05). Elevated LV end-diastolic volume index (β = 0.356, p = 0.016) and RV end-systolic volume index (β = 0.488, p = 0.001) were independently associated with RVMi. Increased systolic blood pressure (β = 0.309, p = 0.004), LV end-systolic volume index (β = 0.633, p < 0.001), and uric acid (β = 0.261, p = 0.013) were independently associated with LVMi. Meanwhile, serum phosphorus (β = 0.519, p = 0.001) was independently associated with native T1 value. In pre-dialysis CKD patients, left and right ventricular remolding has occurred. RVMi and LVMi were the first changed CMR indexes in the development of CKD when eGFR began to drop. Because fluid volume overload was the independent risk factor for RVMi and LVMi increase, reasonable controlling fluid volume overload may slow down the progression of biventricular remolding and may reduce related cardiovascular disease risk.

Evaluation of right ventricular strain in two separate cohorts with precapillary pulmonary hypertension.

Evaluation for right ventricular (RV)dysfunction is an important part of risk assessment in care of patients with pulmonary hypertension (PH) as it is associated with morbidity and mortality. Echocardiography provides a widely available and acceptable method to assess RV function. RV global longitudinal strain (RVGLS), a measure of longitudinal shortening of RV deep muscle fibers obtained by two-dimensional echocardiography, was previously shown to predict short-term mortality in patients with PH. The purpose of the current study was to assess the performance of RVGLS in predicting 1-year outcomes in PH. We retrospectively identified 83 subjects with precapillary PH and then enrolled 50 consecutive prevalent pulmonary arterial hypertension (PAH) subjects into a prospective validation cohort. Death as well as combined morbidity and mortality events at 1 year were assessed as outcomes. In the retrospective cohort, 84% of patients had PAH and the overall 1-year mortality rate was 16%. Less negative RVGLS was marginally better than tricuspid annular plane systolic excursion(TAPSE)as a predictor for death. However, in the prospective cohort, 1-year mortality was only 2%, and RVGLS was not predictive of death or a combined morbidity and mortality outcome. This study supports that RV strain and TAPSE have similar 1-year outcome predictions but highlights that low TAPSE or less negative RV strain measures are often false-positive in a cohort with low baseline mortality risk. While RV failure is considered the final common pathway for disease progression in PAH, echocardiographic measures of RV function may be less informative of risk in serial follow-up of treated PAH patients.

Right ventricular systolic strain in patients with pulmonary hypertension: clinical feasibility, reproducibility, and correlation with ejection fraction.

Right ventricular (RV) systolic function is the major determinant of prognosis in patients with pulmonary hypertension (PH) with quantitative assessment by speckle-tracking strain echocardiography emerging as a viable candidate measure. We evaluated a prospective cohort of 231 patients with known or suspected PH referred for clinical echocardiography. All underwent measurement of RV free-wall systolic strain by sonographer staff. Digital images were recorded for blinded offline assessment by an expert echocardiographer. Reproducibility was assessed using the analysis methods of Bland-Altman and the Cohen's-Kappa coefficient. RV strain was feasible in 213 (92%). The average RV systolic pressure was 59 ± 22mmHg. RV systolic strain correlated with functional class, NT-proBNP, and the degree of RV enlargement. The average free-wall systolic strain was -20 ± 7% (range -2 to -37%). The RV strain measures (clinical practice versus blinded expert) had an excellent correlation with a normal distribution (R2 0.87, p < 0.0001). By Bland-Altman analysis, the mean difference in measurement was -1.7% (95% CI -1.4 to -2.1) with a correlation of 0.93, p value of < 0.0001. The reproducibility of RV strain for clinically relevant thresholds was also excellent (Kappa coefficients 0.68-0.83). There was no effect on the variability of strain measures across body mass, pulmonary pressures, or rhythm. RV strain correlated with RV diastolic volumes and ejection fraction with RV free wall strain being the best echo predictor for a reduction in ejection fraction. Here RV systolic strain was found to be highly feasible and reproducible in clinical practice with excellent levels of agreement for clinically relevant thresholds.

A deep learning approach for automatic echocardiographic right ventricular strain measurements using a limited dataset

Abstract Background Speckle tracking echocardiography provides quantification of myocardial deformation and is useful in the assessment of myocardial function. Right ventricular (RV) strain has been suggested as a sensitive tool for diagnosing cardiomyopathies and assessing long term patient outcomes for patients with pulmonary hypertension, severe tricuspid regurgitation and COVID-19 infection. Recent advances in deep learning (DL) have made promising advances in automating the labour-intensive delineation of regions of interest (ROIs). However, compared to echocardiograms with left ventricular (LV) strain, RV strain data is scarce, making DL models difficult to train. Purpose To investigate whether annotated LV strain data could be beneficial in training a DL model for automatic RV strain when using a limited RV dataset. Methods The dataset consisted of anonymized still frames from 141 echocardiograms of the RV in the RV-focused 4 chamber view with corresponding cardiologist-defined ROI. Exams included healthy subjects and patients with heart failure, valvular disease, and conduction abnormalities. ROIs and still images were extracted at the mid-systole, and then quality assessed by an experienced cardiologist as high, medium, or low. The dataset was randomly split into 68%/17%/15% sets for training, validation, and testing. A convolutional neural network for image segmentation (U-Net) with a residual neural network (ResNet50) encoder was used, with a combination of binary cross entropy and Dice loss functions. Augmentation, predefined ImageNet weights and pre-training were also employed. For pre-training, 715 still images in the apical 4 chamber view with LV defined ROIs were used, both in their original and horizontally flipped view. Predicted ROIs were reintroduced into commercially available echocardiogram analysis software to automatically calculate longitudinal strain (LS) values. Results The model pre-trained with the flipped LV images achieved the highest performance with a mean absolute difference of 1.26 percentage points (95% confidence interval (CI): 0.62–1.89 percentage points) between manually measured and DL-assisted LS. Median absolute LS difference was 0.85 (95% CI: 0.28–1.57) percentage points. A Bland-Altman plot revealed two outliers and no obvious trends. In comparison, the mean and median absolute LS differences for the model without pre-training were 1.87 (95% CI: 0.73–3.00) and 1.09 (95% CI: 0.56–1.63) percentage points, respectively. Conclusions The current study demonstrates that DL-assisted, automated RV strain measurement is feasible even with a small dataset, and that performance can be increased by using images annotated for LV strain. While the majority of the predicted RV strain results were within the typical range of intra- and interobserver variability, a few outliers were observed. These outliers could possibly be avoided with the use of larger datasets. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Research council of Norway

P237 INFLUENCE OF HEART RATE ON LEFT AND RIGHT VENTRICULAR LONGITUDINAL STRAIN IN PATIENTS WITH CHRONIC HEART FAILURE

Abstract Background Myocardial deformation evaluated by two–dimensional speckle tracking echocardiography (STE) is a useful tool to evaluate both left and right ventricular function. However, there are no conclusive data about the relationship between strain measures and heart rate (HR). Aim of the Study To analyse changes in left (LV) and right ventricular (RV) longitudinal strain associated with variations of HR in patients with and without chronic heart failure (CHF). Methods. We enrolled 45 patients. Of the 38 patients diagnosed with CHF, 21 were carrying an ICD (Group 1), and 17 an ICD with CRT (Group 2). Group 3 included 7 participants without CHF with sinus node dysfunction that were carrying a pacemaker. The frequency of atrial stimulation was increased to 90 beats/min and an echocardiogram was performed at each increase of 10 beats/min. Global LV and RV longitudinal strain (LVGLS and RVGLS, respectively) and RV free wall longitudinal strain (RVfwLS) were calculated at each HR, together with other echocardiographic parameters. Worsening or improvement of strain measures was defined as a relative change from baseline of 10%. Results The reproducibility of strain measurements was assessed in all the images obtained at the different HRs for 19 of the study participants. A high degree of reproducibility was observed for LVGLS (ICC = 0.96; 95% CI, 0.93 – 0.97) as well as for RVGLS (ICC = 0.91; 95%CI, 0.86 – 0.94) and RVfwLS (ICC = 0.91; 95%CI, 0.85 – 0.94). When analysed as continuous variables, significant reductions in LVGLS were detected at higher HRs, whereas improvements in both RVGLS and RVfwLS were observed (left panels of the figure). Patients with worsening of LVGLS (76% overall) were more likely to present lower baseline LV function and maximum relative changes of LVGLS correlated significantly with the E/e’ ratios (r = –0.56; p &amp;lt; 0.001). Only few patients (18% for RVGLS and 16% for RVfwLS) exhibited HR–related worsening of RV strain measures, which was associated with lower levels of baseline RV function and higher pulmonary systolic pressures. Finally, 21 (47%) and 25 (56%) of the participants responded with improvements in RVGLS and RVfwLS, respectively. Right panels of the figure show the trend of left and right measures in the different groups. Conclusions Our findings revealed heterogeneous RV and LV responses to increases in HR. These findings might ultimately be used to optimize cardiac functionality at rest in patients diagnosed with CHF.

Propensity Score-Matched Comparison of Right Ventricular Strain in Women and Men Before and After Left Ventricular Assist Device Implantation.

Objective: Adverse events following left ventricular assist device (LVAD) implantation are more common in women than in men, but the impact of gender differences on right ventricular (RV) failure is not well defined. Therefore, we calculated RV strain before and after LVAD implantation in matched groups of men and women to determine if gender differences in RV failure after LVAD might account for the gender differences in overall outcomes. Methods: RV free wall longitudinal strain (FWS) and fractional area change were calculated preoperatively and 3 months postoperatively using speckle-tracking echocardiography analysis. A total of 172 patients (86 women, 86 men) were then propensity score matched (1:1) for comparison. Results: Although women had higher preoperative CHA2DS2-VASc scores and more frequent moderate mitral regurgitation than men (P = 0.018), the preoperative hemodynamic parameters were similar. Preoperative RV-FWS was -6.7% in women and -6.0% in men (P = 0.65). Postoperatively, women had more progression to severe tricuspid regurgitation (TR) than men (15% vs 7%, P = 0.06). At 3 months the RV-FWS was -7.7% in women and -7.0% in men (P = 0.59). Postoperative TR was moderate-severe in 20% of women and in 9% of men (P = 0.001). Women had a higher incidence of venous thromboembolism, cardiac arrhythmias, and bleeding compared with men. Women also had higher mortality rates at discharge and 30 days after surgery, but the survival rates at 5 years were similar. Conclusions: RV strain measurements track standard hemodynamic and echocardiographic parameters and confirm that gender differences in outcomes following LVAD implantation are not related to gender differences in RV failure rates.

Influence of Heart Rate on Left and Right Ventricular Longitudinal Strain in Patients with Chronic Heart Failure

Over the past years, a number of studies have demonstrated the relevance of strain assessed by two-dimensional speckle tracking echocardiography (STE) in evaluating ventricular function. The aim of this study was to analyze changes in left (LV) and right ventricular (RV) longitudinal strain associated with variations of heart rate (HR) in participants with and without chronic heart failure (CHF). We enrolled 45 patients, 38 of these diagnosed with CHF and carrying an implantable cardioverter defibrillator, and seven patients with pacemakers and without CHF. The frequency of atrial stimulation was increased to 90 beats/min and an echocardiogram was performed at each increase of 10 beats/min. Global LV and RV longitudinal strain (LVGLS and RVGLS, respectively) and RV free wall longitudinal strain (RVfwLS) were calculated at each HR. When analyzed as continuous variables, significant reductions in LVGLS were detected at higher HRs, whereas improvements in both RVGLS and RVfwLS were observed. Patients with a worsening of LVGLS (76% overall) were more likely to present lower baseline LV function. Only a few patients (18% for RVGLS and 16% for RVfwLS) exhibited HR-related deteriorations of RV strain measures, which was associated with lower levels of baseline RV function and higher pulmonary systolic pressures. Finally, 21 (47%) and 25 (56%) participants responded with improvements in RVGLS and RVfwLS, respectively. Our findings revealed heterogeneous RV and LV responses to increases in HR. These findings might ultimately be used to optimize cardiac functionality in patients diagnosed with CHF.

Comparison between Nondedicated and Novel Dedicated Tracking Tool for Right Ventricular and Left Atrial Strain

Recently, dedicated speckle-tracking solutions for right ventricular (RV) and left atrial (LA) strain assessment have become commercially available. The purpose of this study was to assess the level of agreement between nondedicated (left ventricular [LV] tracking software) and novel dedicated tracking software for RV and LA strain. In 200 patients with various cardiovascular pathologies, we measured global longitudinal strain (GLS), free wall strain (FWS), and segmental values, as well as LA strain during reservoir, conduit, and contraction phases, by using the (1) LV-tracking software and (2) the novel dedicated tracking software for RV or LA strain analysis. Agreement between corresponding measurements obtained with the LV and dedicated RV or LA software was determined by using mean absolute difference (MAD) and Bland-Altman test. The intra- and interobserver reproducibility related to the nondedicated and novel dedicated tracking software was tested in 30 randomly selected subjects. The dedicated RV-tracking software provided slightly lower strain values without reaching statistical significance. The agreement between software was best for RV GLS (MAD, 2.4±1.8) and significantly poorer for segmental values (MAD ranging from 4.5±3.8 to 5.1±4.0; analysis of variance, P<.05). The intra- and interobserver reproducibility for RV measurements was similar with both software (P>.05 for all parameters). Left atrial mean values showed no statistical difference when obtained with the two tracking tools. The use of LA dedicated tracking software increased significantly the intra- and interobserver reproducibility for LA strain during reservoir and atrial contraction (P<.01 for both). Our results suggest that the choice of tracking software does not significantly impact RV strain measurements. Nonetheless, the use of the same tracking software is recommended when performing serial measurements. The use of the dedicated software for LA strain analysis significantly improved the intra- and interobserver reproducibility.

Strain Estimation of the Murine Right Ventricle Using High-Frequency Speckle-Tracking Ultrasound

Right ventricular (RV) strain measurements from ultrasound via speckle-tracking techniques are being used more frequently as a non-invasive diagnostic tool for a variety of cardiopulmonary pathologies. However, despite the clinical utility of ultrasound RV strain measurements, quantification of RV strain in rodents remains difficult owing to unique image artifacts and non-standardized methodologies. We demonstrate here a simple approach for measuring RV strain in both mice and rats using high-frequency ultrasound and automated speckle tracking. Our results show estimated peak RV free-wall longitudinal strain values (mean ± standard error of the mean) in mice (n = 15) and rats (n = 5) of, respectively, −10.38% ± 0.4% and −4.85% ± 0.42%. We further estimated the 2-D Green–Lagrange strain within the RV free wall, with longitudinal components estimated at −5.7% ± 0.48% in mice and −2.1% ± 0.28% in rats. These methods and data may provide a foundation for future work aimed at evaluating murine RV strain levels in different disease models.

The Prognostic Value of Right Atrial Strain Imaging in Patients with Precapillary Pulmonary Hypertension

Right ventricular (RV) failure in patients with pulmonary hypertension (PH) is associated with unfavorable clinical events and a poor prognosis. Elevation of right atrial (RA) pressure is established as a marker for RV failure. However, the additive prognostic value of RA mechanical function is unclear. The authors tested the hypothesis that RA function by strain echocardiography has prognostic usefulness by studying 165 consecutive patients with precapillary PH defined invasively: mean pulmonary artery pressure ≥ 25mm Hg and pulmonary capillary wedge pressure < 15mm Hg. Speckle-tracking strain analyses of the right atrium and right ventricle were performed, along with routine measures. Peak RA strain values from six segments using generic speckle-tracking software were averaged to RA peak longitudinal strain, representing RA global reservoir function. The primary end point was all-cause mortality during 5years of follow-up. RA strain was similarly analyzed in a control group of 16 normal subjects for comparison. There were 151 patients with PH (mean age, 55±16years; 73% women; mean World Health Organization functional class, 2.6±0.6), after 14 exclusions (three with atrial septal defects and 11 with left ventricular ejection fractions<50%). RA strain measurement was feasible in 93% of patients and RV strain measurement in 88%. RA peak longitudinal strain was significantly reduced in patients with PH compared with control subjects, as expected (P<.001). During 5-year follow-up, 73 patients (48%) died. Patients with RA peak strain in the lowest quartile (<25%) had a significant risk for death (P=.006), even after correcting for confounding variables. RA strain was independently associated with survival in multivariate analysis (P=.039) and had additive prognostic value to RV strain (log-rank P=.01) in subgroup analysis. RA peak longitudinal strain had additive prognostic usefulness to other clinical measures, including RV strain, RA area, and RA pressure, in patients with PH. RA mechanical function by strain imaging has potential for clinical applications in patients with PH.

Abstract 12606: Meta-analysis of the Normal Ranges of Right Ventricular Strains by Echocardiography in Healthy Adults

Background: Right ventricular (RV) systolic strain has been increasingly shown to be prognostic in some cardiovascular diseases. Despite this, the reference range including the lower limit of normal (LLN) and factors associated with RV strain measurements are not well-established. This meta-analysis aimed to determine the means and LLNs of two- (2D) and three-dimensional (3D) right ventricular global (RVGLS), free wall (RVFWLS) and septal wall (RVSWLS) longitudinal strains in healthy individuals and factors affecting strain measurements. Methods: Pubmed, Embase and Cochrane databases were searched until 31 December 2019 for eligible studies reporting RVGLS, RVFWLS and/or RVSWLS in at least 30 healthy subjects. We pooled the means and LLNs of RV strains by two- (2D) and three- (3D) dimensional echocardiography, and performed meta-regression analyses. Results: From 591 articles screened, 37 eligible studies totaling 2970 subjects were analyzed. Pooled means and LLNs (95% confidence intervals) for 2D- strains were RVGLS -23.3% (-24.3%, -22.3%) and -16.2% (-17.2%, -15.1%) in 22 studies; RVFWLS -27.2% (-28.5%, -25.9%) and 18.5% (-20.0%, -17.1%) in 23 studies; RVSWLS -20.4% (-22.0%, -18.9%) and -11.5% (-13.6%, -9.6%) in 10 studies; and similar results for 3D- RV strains (Table). Right ventricular fractional area change and vendor software were associated with 2D-RVGLS and RVFWLS means and LLNs. Conclusion: We reported the pooled means and LLNs of RV systolic strains in healthy subjects, to define thresholds for abnormal, borderline and normal strains. Important factors associated with RV systolic strains include right ventricular fractional area change and vendor software.

Strain and Strain Rate To Evaluate Right Heart Function of Ebstein Anomaly (EA) Patients Before and After Operation.

This study was aimed to elucidate the feasibility of using right ventricular (RV) strain and strain rate to evaluate right heart function of Ebstein anomaly (EA) patients before and after operation. Sixty EA patients and 30 healthy controls underwent echocardiography (UCG) for evaluation of right heart function. Preoperative UCG and 1-week and 3-month postoperative UCG were performed in EA patients. RV strain and strain rate were measured on the four-chamber section of tissue Doppler imaging (TDI). The strain and strain rate representative of right ventricle systolic function were reduced prior to operation. RV strain and strain rate improved after the operation (P < .001), most significantly in the basal segment and middle segment of the free wall of the right ventricle as well as the basal segment of the interventricular septum (P < .001). The measurement of RV strain and strain rate on tissue Doppler imaging can be employed to assess the preoperative and postoperative RV function, proves the positive effect of tricuspid valve repair on right heart function, and offers more insight on right heart function evaluation.

P1535 Interventricular interaction can result in right ventricular dysfunction in interventricular septum involved myocardial infarction patient

Abstract Background Previous studies revealed that interventricular septal thickness is related to right ventricular dysfunction after anterior myocardial infarction. This finding suggest that interventricular septal function can affect right ventricular function in myocardial infarction patients. We assumed that right ventricular free wall strain values measured using dedicated software can be affected in the setting of ischemic insult on interventricular septum in long-term follow up. Methods The patients diagnosed as acute myocardial infarction due to left anterior descending artery disease who underwent successful revascularization were enrolled. Echocardiographic exams were performed at least 2 times, within 72 hours and 1 year after the revascularization. Strain values of interventricular septum and right ventricular free wall were derived from the raw-dicom images. The analysis was performed using the dedicated software for the measurement of right ventricular strain. Results Total 65 patients were enrolled. The values of global left ventricular strain were increased after the follow up. There were no changes in global longitudinal strain of the right ventricle. But longitudinal stain values acquired from right ventricular free walls were decreased even the strain values measured at left ventricle and interventricular septum were improved. Conclusion Interventricular septal dysfunction due to ischemic injury can affect long term right ventricular dysfunction. This finding suggests the interventricular dependence between cardiac chambers and can provide the development of heart failure in myocardial infarction patient even after the successful revascularization. Strain values of both ventricles Left ventricle after revascularization (n = 65) 1 year later (n = 65) P values Global longitudinal strain (%) -12.84 ± 4.50 -15.62 ± 4.45 &amp;lt;0.001 Septal longitudinal strain (%) -10.77 ± 5.96 -14.02 ± 5.26 &amp;lt;0.001 Right ventricle Global longitudinal strain (%) -19.36 ± 4.57 -19.47 ± 4.83 0.872 Septal longitudinal strain (%) -14.82 ± 4.48 -16.43 ± 6.03 0.055 Free wall longitudinal strain (%) -20.23 ± 5.33 -17.82 ± 5.70 0.010 Abstract P1535 Figure. Right ventricular segmental strain

Myocardial Function Assessed by Multi-Layered Two-Dimensional Speckle Tracking Analysis in Asymptomatic Young Subjects with Diabetes Mellitus Type 1

Background: Diabetes mellitus type 1 (DM1) is associated with a high risk for cardiovascular disease, and early detection of myocardial dysfunction is crucial for the prevention of cardiac complications. Objectives: The aim of this study was to evaluate left ventricular (LV) and right ventricular (RV) function by using both conventional echocardiography as well as multi-layered speckle tracking echocardiography (STE) in young adults with DM1. Methods: We included 50 young asymptomatic adults diagnosed with DM1 (mean interval from diagnosis 9 ± 6 years) and 80 healthy controls. STE was acquired using the GE Vivid S60 equipment. The LV longitudinal strain (LS), layer-specific strains of the endocardium, myocardium, and epicardium (global longitudinal strain [GLS]_endo, GLS_myo, GLS_epi) as well as RV strain were obtained using the EchoPAC BT13 workstation. Results: No significant intergroup differences in LV ejection fraction were noted. GLS_endo and GLS_myo were reduced in the DM1 group (–20.6 ± 2.7 vs. –22.0 ± 2.3 and –18.0 ± 2.4 vs. –19.1 ± 1.9, respectively, p < 0.05) compared to controls. Mechanical dispersion was higher in the diabetes group (34 ± 11 vs. 29 ± 7, p < 0.05). RV strain measurements showed no significant difference between the groups. Conclusions: Young adults with DM1 and without known heart disease have subclinical myocardial dysfunction with lower LV endocardium and myocardium LS and higher mechanical dispersion demonstrated by multi-layered STE.

Regional right ventricular function in rats: a novel magnetic resonance imaging method for measurement of right ventricular strain.

The function of the right ventricle (RV) is linked to clinical outcome in many cardiovascular diseases, but its role in experimental heart failure remains largely unexplored due to difficulties in measuring RV function in vivo. We aimed to advance RV imaging by establishing phase-contrast MRI (PC-MRI) as a robust method for measuring RV function in rodents. A total of 46 Wistar-Hannover rats with left ventricular (LV) myocardial infarction and 10 control rats (sham) were examined 6 wk after surgery. Using a 9.4-T preclinical MRI system, we utilized PC-MRI to measure strain/strain rate in the RV free wall under isoflurane anesthesia. Cine MRI was used to measure RV volumes. LV end-diastolic pressure (LVEDP) was measured and used to identify pulmonary congestion. The infarct rats were divided into two groups: those with signs of pulmonary congestion (PC), with LVEDP ≥ 15 mmHg (n = 26) and those without signs of pulmonary congestion (NPC), with LVEDP < 15 mmHg (n = 20). The NPC rats exhibited preserved RV strains/strain rates, whereas the PC rats exhibited reduced strains/strain rates (26-48% lower than sham). Of the strain parameters, longitudinal strain and strain rate exhibited the highest correlations to LVEDP and lung weight (rho = 0.65-0.72, P < 0.001). Basal longitudinal strain was most closely associated with signs of pulmonary congestion and indexes of RV remodeling. Longitudinal RV strain had higher area under the curve than ejection fraction for detecting subtle RV dysfunction (area under the curve = 0.85 vs. 0.67). In conclusion, we show for the first time that global and regional RV myocardial strain can be measured robustly in rodents. Reduced RV strain was closely associated with indexes of pulmonary congestion and molecular markers of RV remodeling.NEW & NOTEWORTHY Global and regional right ventricular myocardial strain can be measured with high reproducibility and low interobserver variability in rodents using tissue phase mapping MRI. Reduced right ventricular strain was associated with indexes of pulmonary congestion and molecular markers of right ventricular remodeling. Regional strain in the basal myocardium was considerably higher than in the apical myocardium.

The Role of Right Ventricular Strain in Women and Men Following Left Ventricular Assist Device Implantation

BackgroundWomen and men have different perioperative hemodynamics, adverse event rates, and pump thrombosis-related mortality following left ventricular assist device (LVAD) implantation. However, gender differences in the subsequent development of right ventricular (RV) failure are not well defined. We evaluated the impact of gender on RV failure following LVAD implantation by speckle-tracking analysis of pre- and postoperative echocardiograms (echo).MethodsPre- and post-operative clinical, echo, and hemodynamic parameters were recorded in patients receiving LVADs from 2008-2018. Retrospectively, a subgroup of 74 women and 74 men were propensity score-matched 1:1 and chi square, t-tests, nonparametric tests, regression analysis, and Kaplan-Meier analysis were used to compare event rates. RV free-wall longitudinal strain (RV-FLS) and RV Fractional Area Change (RV-FAC) were calculated retrospectively using speckle-tracking, Tomtec Arena. All echo and RV strain measurements were blinded to gender outcomes.ResultsPreoperative hemodynamic parameters were not different between the two groups. However, women were more likely to have non-ischemic cardiomyopathy (81% vs 65%; p<0.001) and higher CHADS2VASC scores (3.0 vs 2.5; p<0.001), while men were more likely to have ischemic cardiomyopathy (35% vs 19%; p<0.026). Postoperative ICU stays were longer for women than men (149 vs 98 hours, respectively; p<0.016), as was the need for prolonged ventilation (61% vs 41%, respectively; p=0.014) and blood products (77% vs 62%, respectively; p=0.049). All echo parameters are presented in the table. The delta between pre and post-op RV free wall strain was not significant. Two year survival was 66.4% for the female group and 70.2% for the male group and 5-year survival was 55.3% for males and 63.6% for females (Fig 1).ConclusionsRV strain analysis tracks standard hemodynamic and echo parameters and does not add to the assessment of RV function in women and men undergoing LVAD implantation. Women and men have different perioperative hemodynamics, adverse event rates, and pump thrombosis-related mortality following left ventricular assist device (LVAD) implantation. However, gender differences in the subsequent development of right ventricular (RV) failure are not well defined. We evaluated the impact of gender on RV failure following LVAD implantation by speckle-tracking analysis of pre- and postoperative echocardiograms (echo). Pre- and post-operative clinical, echo, and hemodynamic parameters were recorded in patients receiving LVADs from 2008-2018. Retrospectively, a subgroup of 74 women and 74 men were propensity score-matched 1:1 and chi square, t-tests, nonparametric tests, regression analysis, and Kaplan-Meier analysis were used to compare event rates. RV free-wall longitudinal strain (RV-FLS) and RV Fractional Area Change (RV-FAC) were calculated retrospectively using speckle-tracking, Tomtec Arena. All echo and RV strain measurements were blinded to gender outcomes. Preoperative hemodynamic parameters were not different between the two groups. However, women were more likely to have non-ischemic cardiomyopathy (81% vs 65%; p<0.001) and higher CHADS2VASC scores (3.0 vs 2.5; p<0.001), while men were more likely to have ischemic cardiomyopathy (35% vs 19%; p<0.026). Postoperative ICU stays were longer for women than men (149 vs 98 hours, respectively; p<0.016), as was the need for prolonged ventilation (61% vs 41%, respectively; p=0.014) and blood products (77% vs 62%, respectively; p=0.049). All echo parameters are presented in the table. The delta between pre and post-op RV free wall strain was not significant. Two year survival was 66.4% for the female group and 70.2% for the male group and 5-year survival was 55.3% for males and 63.6% for females (Fig 1). RV strain analysis tracks standard hemodynamic and echo parameters and does not add to the assessment of RV function in women and men undergoing LVAD implantation.

Interventricular Septal Dysfunction Due to Myocardial Infraction Can Result in Right Ventricular Failure in Long Term Follow Up

Background Diastolic functional parameters and interventricular septal thickness are related to right ventricular dysfunction after anterior myocardial infarction. This finding suggest that interventricular septal function can affect right ventricular function in myocardial infarction patients. We measured right ventricular free wall strain using dedicated software whether the ischemic insult on interventricular septum can affect the long-term right ventricular function, which is important parameter for the development of heart failure. Methods The patients diagnosed as acute myocardial infarction due to left anterior descending artery disease who underwent successful revascularization were enrolled. Echocardiographic exams were performed 2 times, within 72 hours and 1 year after the revascularization. Strain values of interventricular septum and right ventricular free wall were derived from the Dicom images. And the analysis was performed using the dedicated software for the measurement of right ventricular strain. Results Total 53 patients were enrolled. The values of global left ventricular strain were increased after the follow up. There were no changes in global longitudinal strain of the right ventricle. But longitudinal stain values acquired from right ventricular free walls were decreased even the improved left ventricular strain values. Conclusions Interventricular septal dysfunction due to ischemic injury resulted from anterior myocardial infarction can affect long term right ventricular dysfunction. This finding suggests the interventricular dependence between cardiac chambers and can provide the development of heart failure in myocardial infarction patient after the successful revascularization.

Regional Versus Global Measurements of Right Ventricular Strain Performed in the Operating Room With Transesophageal Echocardiography

To compare regional and global measures of right ventricular (RV) strain in patients undergoing intraoperative transesophageal echocardiography (TEE). Prospective, nonrandomized, observational study. Single tertiary-level, university hospital. The study comprised 48 patients undergoing intraoperative TEE. None. A global RV strain measurement (termed RV 5-wall strain [RV 5WS]) was calculated by averaging the longitudinal strain calculated from multiple TEE views. This global strain measurement was compared with the more standard regional strain measurements obtained in a single 4-chamber view (RV free-wall strain [RV FWS] and RV global longitudinal strain [RV GLS]) and with traditional measures of RV function. Regional and global strain measurements were feasible in the operating room. RV FWS and RV GLS strongly correlated with RV 5WS (r = 0.86 and 0.87, respectively) with no significant bias and limits of agreement of approximately -5% to 5%. RV FWS and RV GLS were even more closely correlated with each other (r = 0.99) with no significant bias and limits of agreement less than -2% to 2%. Both regional and global RV strain measurements showed a high sensitivity (RV FWS 94%; RV GLS 94%; RV 5WS 89%) and moderate specificity (RV FWS 70%; RV GLS 67%; RV 5WS 63%) for RV dysfunction based on a reference standard of 3-dimensional RV ejection fraction. Both regional and global RV strain measurements are feasible in the operating room with TEE. Regional and global measures of RV function correlate well and are sensitive indicators of RV dysfunction.

Association of Echocardiographic Parameters of Right Ventricular Remodeling and Myocardial Performance With Modified Task Force Criteria in Adolescents With Arrhythmogenic Right Ventricular Cardiomyopathy.

The usefulness of echocardiographic indices, including those already used by modified Task Force Criteria (mTFC), and others such as strain imaging, to identify arrhythmogenic right ventricular cardiomyopathy (ARVC) in adolescence is not well established. Echocardiograms from 120 adolescents investigated for ARVC (13±4 years) were retrospectively analyzed. According to the mTFC, patients were classified into definite (n=38), borderline (n=39), or possible (n=43) ARVC. Results were compared with 35 healthy controls. mTFC echocardiographic parameters were analyzed, as well as comprehensive right ventricular (RV) and left ventricular assessment of function including parameters not included in mTFC such as pulsed-wave tissue Doppler and RV 2-dimensional speckle strain. mTFC parameters indexed for body surface area were significantly more abnormal in patients with possible, borderline, or definite ARVC compared with controls for parasternal long-axis view of the RV outflow tract. RV end-diastolic diameters were significantly larger in patients versus controls, a difference that increased with likelihood of ARVC. Left ventricular ejection fraction, tricuspid annular peak systolic excursion, and systolic and diastolic pulsed-wave tissue Doppler imaging indices were similar to controls for all groups. Average and segmental RV peak longitudinal systolic strain was significantly lower in patients with definite ARVC (-21±4%) and disease subgroups versus controls (-25±3%). Multivariable risk analysis showed that reduced RV strain was significantly associated with ARVC diagnosis and its likelihood (multivariable odds ratio [95% CI]=1.23 [1.1-1.37]; P<0.001) as was increased end-diastolic diameter at the apical third of the RV (multivariable odds ratio [95% CI]=1.51 [1.33-1.72]; P<0.001). mTFC echocardiographic criteria are significantly different between patients and controls and between the different diagnostic groups. However, in our cohort, current echocardiographic mTFC are not met by the majority of adolescent ARVC patients, particularly when indexed to body surface area. Measurement of RV apical dimensions and strain may increase the diagnostic yield of echocardiography for ARVC.

Serial Strain Analysis Identifies Hypoplastic Left Heart Syndrome Infants at Risk for Cardiac Morbidity and Mortality: A Pilot Study

Validated, objective measures of right ventricular (RV) function assessment in hypoplastic left heart syndrome (HLHS) are needed. In other populations, speckle-tracking echocardiography-derived strain is a sensitive measure that outperforms conventional parameters of RV function. We hypothesized that speckle-tracking echocardiography-derived measures of RV function would be worse in patients with HLHS who have a poor cardiac outcome. Prospective serial echocardiography was performed in 35 infants with HLHS during the first 6months of life. Patients not undergoing staged palliation or with other variants of single RV were excluded. Traditional RV measurements and strain analysis were performed from standard apical and basal views. The primary outcome of cardiac death, heart transplantation, or persistent ≥moderate RV dysfunction was examined using Cox regression analysis, and receiver operating characteristic curve analyses were performed to derive cutoff values. At median follow-up of 10.9months (interquartile range 5.6, 15.2), eight patients reached the outcome and demonstrated worse RV strain measures compared with those without the outcome. A post-Norwood global longitudinal strain (GLS) of>-16% (area under the curve [AUC]=0.76; P=.04) and pre-Glenn GLS>-13% (AUC, 0.98; P≤.01) were highly sensitive and specific for poor outcome. Other thresholds included post-Norwood GLS rate (GLSr)>-1.15 %/s (AUC, 0.78; P=.03), pre-Glenn GLSr=-0.85%/sec (AUC, 0.89; P<.01), post-Glenn circumferential strain rate>-0.85%/sec (AUC, 0.92; P<.01), and GLSr>-0.85%/sec (AUC, 0.84; P=.02). Strain analysis may help identify at-risk HLHS infants. In this pilot study, interstage strain indices were worse in infants with HLHS who had a poor cardiac outcome.