The non-invasive echocardiographic assessment of right ventricular myocardial work in a healthy population.

BACKGROUND: Non-invasive right ventricular (RV) myocardial work (RVMW) is the latest indicator used to assess RV function. Nevertheless, the physiological determinants of RVMW have not been studied, and reference ranges for normal RVMW indices have yet to be established. METHODS: A total of 263 healthy volunteers (median age: 34 years, males: 38%) were prospectively enrolled. RVMW indices were analysed by an RV pressure-strain loop (RVPSL) in specific software. RESULTS: The lowest values of the RVMW indices in males and females were 133 mmHg% and 206 mmHg% for RV global work index (RVGWI), 165 mmHg% and 241 mmHg% for RV global constructive work (RVGCW) and 78% and 83% for RV global work efficiency (RVGWE), respectively. The highest values for RV global wasted work (RVGWW) in males and females were 67 mmHg% and 69 mmHg%, respectively. RVGWI and RVGCW were significantly lower in males than those in females. RVGWW significantly increased with age in males and females. RVGWE significantly decreased with age in females. Multivariable analysis revealed that RVGWI, RVGCW and RVGWE increased as pulmonary artery systolic pressure (PASP) increased. CONCLUSIONS: Normal reference values of non-invasive RVMW were obtained by echocardiography. Quantitative data on RVMW could be essential in clinical work and clinical experiments.

Echocardiographic reference ranges for noninvasive left ventricular 18-segment myocardial work index and work efficiency in a healthy Asian population.

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.

Dynamic assessment of the tricuspid annulus in a healthy Asian population: A four-dimensional echocardiography study.

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.

Diagnostic Value of Color Doppler Ultrasonography in Subacute Thyroiditis.

In order to explore the clinical effect of color Doppler ultrasonography in the diagnosis of subacute thyroiditis, a method for the diagnosis of subacute thyroiditis by color Doppler ultrasonography was proposed. From November 2019 to November 2020, 90 patients with subacute thyroiditis in our hospital were selected as the experimental group; 90 healthy people were selected as the control group during the same period. Both groups were diagnosed by color Doppler ultrasonography and compared. The experimental results showed that patients with subacute thyroiditis showed mild to moderate enlargement of the involved thyroid gland, and local or diffuse inhomogeneous hypoechoic areas may appear in bilateral or unilateral thyroid glands: irregular edges, unclear boundaries, no "ball feel," mottled changes, and accompanied by tenderness. The blood flow signal around the hypoechoic area is rich, and the internal blood flow signal is less. There was no significant increase in the blood flow velocity of the superior thyroid artery on the affected side. Color Doppler ultrasound not only is simple, economical, and non-invasive but also has a good diagnostic accuracy for subacute thyroiditis, which can provide an important basis for clinical diagnosis and treatment and is worthy of popularization and application.

Correlations among noninvasive right ventricular myocardial work indices and the main parameters of systolic and diastolic functions.

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.

Evaluation of cardiac synchrony in left bundle branch pacing: Insights from echocardiographic research.

AIM: The aim of this study is to assess if left bundle branch pacing (LBBP) can preserve physiological cardiac synchrony and deliver favorable hemodynamic effects. METHODS: Consecutive patients undergoing dual chamber pacemaker implantation for sick sinus syndrome (SSS) and a normal cardiac function with a narrow QRS complex were recruited for the study. Electrocardiogram and echocardiographic examinations were performed during ventricular pacing-on and native-conduction modes. The QRS duration (QRSd), systolic dyssynchrony index (SDI), and the standard deviation of time-to-peak contraction velocity in left ventricular (LV) 12 segments (Tsd-12-LV) were measured to evaluate LV synchrony. The stroke volume (SV) and the degree of atrioventricular valvular regurgitation were also assessed. RESULTS: A total of 40 patients underwent LBBP, while another 38 patients underwent right ventricular septum pacing (RVSP) as control group. Baseline characteristics were similar between the two groups. With LBBP, the paced QRSd was slightly wider than the intrinsic QRSd (101.03 ± 8.79 ms vs 91.06 ± 14.17 ms, P < .0001) while the LV mechanical synchrony during LBBP pacing mode was similar to that of native-conduction mode (SDI, 3.14 ± 2.49 vs 2.70 ± 1.68, P = 0.129; Tsd-12-LV, 26.43 ± 15.55 vs 25.61 ± 16.07, P = .671) in the LBBP group. The LV synchrony in the LBBP group was superior to the RVSP group significantly. No significant differences in SV (64.08 ± 16.97 mL vs 65.45 ± 18.68 mL, P = .241) or the degree of atrioventricular valvular regurgitation were noted between LBBP capture and native-conduction modes. CONCLUSION: LBBP could preserve satisfactory LV synchrony and result in favorable hemodynamic effects.