Background: Right ventricular (RV) myocardial work (RVMW) is the latest method used to assess RV function. To date, correlations among RVMW indices and RV systolic and diastolic functions have not been studied.Methods: A total of 106 healthy volunteers (median age, 34 years; 46% male) were prospectively enrolled. RVMW indices were measured using the RV pressure-strain loop using specific software. The correlations among RVMW indices and other RV functions were analyzed. Results: During the multivariate analysis, the RV global work index (RVGWI) was significantly correlated with RV global longitudinal strain (RV GLS) (p < .0001), pulmonary systolic artery pressure (PASP) (p < .0001), and tricuspid annular (TA) plane systolic excursion (TAPSE) (p = .036). RV global constructive work (RVGCW) was correlated with RV GLS (p < .0001) and PASP (p < .0001). RV global wasted work (RVGWW) was correlated with RV GLS (p = .008) and TA isovolumetric acceleration (TA IVA) (p = .008). RV global work efficiency (RVGWE) was correlated with RV GLS (p < .0001) and tissue Doppler (TD) RV myocardial performance index (TD RMPI) (p = .043). Conclusion: RVMW indices showed good correlations with RV myocardial systolic function.
Background Noninvasive right ventricular (RV) myocardial work (RVMW) determined by echocardiography is a novel indicator used to estimate RV systolic function. To date, the feasibility of using RVMW has not been verified in assessing RV function in patients with atrial septal defect (ASD). Methods Noninvasive RVMW was analysed in 29 ASD patients (median age, 49 years; 21% male) and 29 age- and sex-matched individuals without cardiovascular disease. The ASD patients underwent echocardiography and right heart catheterization (RHC) within 24 h. Results The RV global work index (RVGWI), RV global constructive work (RVGCW), and RV global wasted work (RVGWW) were significantly higher in the ASD patients than in the controls, while there was no significant difference in RV global work efficiency (RVGWE). RV global longitudinal strain (RV GLS), RVGWI, RVGCW, and RVGWW demonstrated significant correlations with RHC-derived stroke volume (SV) and SV index. The RVGWI (area under receiver operating characteristic curve [AUC] = 0.895), RVGCW (AUC = 0.922), and RVGWW (AUC = 0.870) could be considered good predictors of ASD and were superior to RV GLS (AUC = 0.656). Conclusion The RVGWI, RVGCW, and RVGWW could be used to assess RV systolic function and are correlated with RHC-derived SV and SV index in patients with ASD. Graphical Abstract
Background The novel method of left bundle branch pacing (LBBP) has been reported to achieve better electrical and mechanical synchrony in the left ventricle than conventional right ventricular pacing (RVP). However, its effects on right ventricle (RV) performance are still unknown. Methods Consecutive patients undergoing dual‐chamber pacemaker (PM) implantation for sick sinus syndrome (SSS) with normal cardiac function and a narrow QRS complex were recruited for the study. The pacing characteristics and echocardiogram parameters were measured to evaluate RV function, interventricular and RV synchrony, and were compared between ventricular pacing‐on and native‐conduction modes. Results A total of 84 patients diagnosed with SSS and an indication for pacing therapy were enrolled. Forty‐two patients (50%; mean age 65.50 ± 9.30 years; 35% male) underwent successful LBBP and 42 patients (50%; mean age 69.26 ± 10.08 years; 33% male) RVSP, respectively. Baseline characteristics were similar between the two groups. We found no significant differences in RV function [RV‐FAC (Fractional Area Change)%, 47.13 ± 5.69 versus 48.60 ± 5.83, p = .069; Endo‐GLS (Global Longitudinal Strain)%, −28.88 ± 4.94 versus −29.82 ± 5.35, p = .114; Myo‐GLS%, −25.72 ± 4.75 versus −25.72 ± 5.21, p = .559; Free Wall St%, 27.40 ± 8.03 versus −28.71 ± 7.34, p = .304] between the native‐conduction and LBBP capture modes, while the RVSP capture mode was associated with a significant reduction in the above parameters compared with the native‐conduction mode (p < .0001). The interventricular synchrony in the LBBP group was also superior to the RVSP group significantly. Conclusion LBBP is a pacing technique that seems to associate with a positive and protective impact on RV performance.
Background Left ventricular (LV) myocardial work index (WI) and work efficiency (WE) have become the latest indicators for assessing LV function. Reference ranges for normal LV segmental WI and WE have not been established. Methods Four hundred eleven healthy Asian subjects (47% men, median age: 35 years) were enrolled prospectively. WI and WE were analysed using the LV pressure–strain loop (LVPSL) with specific software. Results WI and WE differed significantly between segments as well as between walls and levels of the left ventricle. The anteroseptal basal segment had the lowest WI and WE (1440 mmHg ± 324 and 92% [88–96], respectively) among the eighteen segments. Significant WI and WE differences were found between sexes and age groups. No correlation was observed between age groups and the average WI of any wall or level in men, while the average WI of several different walls and levels in women showed significant differences between age groups. The average WI of most walls and levels increased with age in women. No correlation was found between age groups and the average WE of any wall or level in either men or women. Conclusions This study establishes the normal reference values of WI and WE of eighteen segments for clinical work and clinical experiments. There were significant differences in WI and WE between segments, levels, and walls of the normal left ventricle. Sex should be considered when analysing WI and WE. Age should be considered when analysing WI in women. Graphical Abstract
This paper gives a quantitative account of the influence of slipstream on the aerodynamic performance of a contrarotating propeller (CRP)/wing system, and compares it with the CRP and clean wing. To accurately evaluate the complex aerodynamic interaction, the unsteady Reynolds-averaged Navier–Stokes approach using the sliding mesh method is performed at a typical freestream velocity of 30 m/s. Four different critical parameters, including the freestream angle of attack (AoA), axial spacing between the front propeller (FP) and rear propeller (RP), number of blades, and rotational speed, are considered in the present work. The results show that the thrust coefficient, power coefficient, and propulsion efficiency of the CRP/wing system change sharply and the difference in amplitude between adjacent waves is large. In particular, the propeller slipstream has a significant impact on the lift–drag performance of the wing in the case of a nonzero AoA. The presence of a wing also increases the efficiency of propulsion due to the recovery of vortices. In the case of a small axial spacing, the thrust coefficient value of the FP is significantly smaller than that of the RP. However, when the axial spacing exceeds a certain value, the opposite relationship is obtained. When the rotational speed increases from 3695 RPM to 8867 RPM, the lift coefficient and drag coefficient of the wing gradually increase.
Background Tricuspid annulus (TA) geometry and function reference values are limited, especially for Asian populations. We aimed to explore TA using four‐dimensional echocardiography (4DE) in a healthy Asian population. Methods A total of 355 healthy Asian volunteers (median age 34 years; 52% males) were prospectively enrolled. TA geometry and function were analyzed using 4DE throughout the cardiac cycle. Results The TA area, perimeter, and dimensions were smallest at end systole (ES) and largest at late diastole (LD). Normal TA parameters at end diastole (ED) in different sex and age groups were obtained. TA areas, perimeters, and dimensions in males were significantly larger than those in females at ED; BSA‐indexed perimeters and BSA‐indexed dimensions in males were significantly smaller than those in females at ED. TA parameters correlated well with tricuspid valve (TV) tenting, right ventricle (RV), and right atrium (RA) parameters. Conclusions Reference values of TA parameters were obtained by 4DE in an Asian population. Quantitative data on TA geometry and function are essential for TA pathology and therapeutics.
The cover image is based on the Original Article Dynamic assessment of the tricuspid annulus in a healthy Asian population: A four‐dimensional echocardiography study by Jian Wu MD et al., https://doi.org/10.1111/echo.15528.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.