Interaction effect of hypertension and obesity on left atrial phasic function: a three-dimensional echocardiography study.

Background:Hypertension (HT) and obesity often coexist and contribute to left atrial (LA) dysfunction. The present study aimed to compare LA function in hypertensive individuals and control participants with different body mass index (BMI) categories and to explore whether there is an interaction effect between HT and obesity on LA function.Methods:In this cross-sectional study, a total of 258 individuals (145 hypertensive and 113 non-hypertensive patients) were prospectively enrolled from Fuwai Central China Cardiovascular Hospital from September 2020 to November 2021. Hypertensive and non-hypertensive patients were both divided into three study subgroups (n=35 per group) according to their BMI: normal weight (BMI 18.5-<25 kg/m2), overweight (BMI 25-<30 kg/m2), and obesity (BMI ≥30 kg/m2) groups. LA volume and strain parameters were obtained using three-dimensional echocardiography.Results:A significant interaction effect between HT and obesity on LA function was observed [PInteraction =0.04, 0.03, 0.005, 0.01, and 0.002 for LA ejection fraction (LAEF), LA passive ejection fraction (LAPEF), LA active ejection fraction (LAAEF), LA reservoir longitudinal strain (LASr), and LA contraction longitudinal strain (LASct), respectively; PInteraction <0.001 for LA conduit longitudinal strain (LAScd)]. Univariate correlation analysis revealed that HT [LASr, r=-0.53, 95% confidence interval (CI): -0.62 to -0.42, P<0.001; LAScd, r=-0.49, 95% CI: -0.58 to -0.39, P<0.001; and LASct, r=-0.46, 95% CI: -0.55 to -0.34, P<0.001] and BMI categories (LASr, r=-0.68, 95% CI: -0.75 to -0.61, P<0.001; LAScd, r=-0.47, 95% CI: -0.57 to -0.35, P<0.001; and LASct, r=-0.73, 95% CI: -0.78 to -0.66, P<0.001) were negatively correlated with LA strains. A generalized linear model further demonstrated that there was an interaction effect between HT and obesity on LA strains after adjusting for confounding factors (Model 2: LASr, βHT*Obesity =-1.91, 95% CI: -3.48 to -0.35, P=0.01; LAScd, βHT*Obesity =-3.26, 95% CI: -4.83 to -1.70, P<0.001; LASct, βHT*Overweight =-1.97, 95% CI: -3.03 to -0.91, P<0.001; βHT*Obesity =-1.54, 95% CI: -2.67 to -0.41, P=0.007).Conclusions:Both HT and increasing BMI category had an adverse effect on LA function. The coexistence of HT and obesity further impaired LA performance in an interaction manner. Weight loss is essential to reduce the incidence of adverse cardiovascular events in hypertensive patients.

Interaction effect of type 2 diabetes mellitus and hypertension on left atrial function: a three-dimensional echocardiography study.

Background:Type 2 diabetes mellitus (T2DM) and hypertension (HT) often coexist and contribute to left atrial (LA) functional abnormalities. The aim of the present study was to explore whether there is a potential interaction effect between T2DM and HT on LA function.Methods:A total of 135 patients (45 with T2DM only, 45 with HT only, and 45 with both T2DM and HT) were enrolled and compared to 45 age- and sex-matched controls. LA volume fraction, including LA ejection fraction (LAEF), LA expansion index (LAEI), LA passive emptying fraction (LAPEF), and LA active emptying fraction (LAAEF), and strain parameters, including LA reservoir longitudinal strain (LASr), LA conduit longitudinal strain (LAScd), and LA contraction longitudinal strain (LASct), were obtained using three-dimensional echocardiography (3DE).Results:Patients with T2DM had significantly more impaired LA reservoir and conduit functions compared to those without T2DM (P<0.05), and patients with HT had a significantly more impaired LA reservoir function, conduit function, and booster pump function compared to those without HT (P<0.05). Two-way analysis of variance showed that there were significant additive interaction effects between T2DM and HT with respect to LASr (PT2DM + HT =0.002) and LAScd (PT2DM + HT =0.001). Generalized linear model demonstrated that T2DM + HT had a greater relative contribution than either T2DM or HT alone to the LA strain indexes, even after adjustment for other confounders (LASr, βT2DM + HT =-3.931, 95% CI: -6.237 to -1.624, P=0.001; LAScd, βT2DM + HT=-3.781, 95% CI: -5.653 to -1.908, P<0.001).Conclusions:Both T2DM and HT had an adverse effect on LA function. The coexistence of both conditions further impaired LA performance in an additive interaction fashion.

Evaluation of myocardial work in patients with hypertrophic cardiomyopathy and hypertensive left ventricular hypertrophy based on non-invasive pressure-strain loops.

Background:The capacity to distinguish hypertrophic cardiomyopathy (HCM) from hypertensive left ventricular hypertrophy (H-LVH) based on morphological features obtained by conventional echocardiography is limited. We investigated the global myocardial work of the left ventricle in two types of hypertrophies using the non-invasive myocardial work index (NMWI).Methods:Conventional echocardiography was performed on 107 subjects with preserved left ventricular ejection fraction (LVEF ≥ 50%), who comprised patients with HCM (n = 40), H-LVH (n = 35), and healthy people with normal blood pressure and left ventricular structure (n = 32). Except for the conventional echocardiographic parameters, the left ventricular myocardial work parameters based on pressure-strain loops, including global myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE), were evaluated in three groups. Multivariate discriminant analysis and receiver operating characteristic (ROC) curve were used to evaluate the incremental value of NMWI for distinguishing HCM from H-LVH.Results:Compared to the control group, GWI and GCW were significantly lower in HCM patients (P < 0.05), whereas GWI was significantly higher in H-LVH patients. GWW was higher and GWE was significantly decreased in both HCM and H-LVH patients than in the control group (P < 0.05). Multivariate discriminant analysis and ROC curve revealed that the inter-ventricular septum thickness (IVST)/left ventricular posterior wall thickness (LVPWT) and GCW were each able to distinguish HCM from H-LVH. The combination of IVST/LVPWT and GCW discriminated HCM and H-LVH with a higher predictive accuracy of 94.7%.Conclusion:NMWI may provide additional information in evaluating the myocardial function in patients with HCM and H-LVH. Myocardial work combined with conventional echocardiography could improve the clinical diagnostic accuracy of distinguishing HCM and H-LVH.

Non-invasive myocardial work index contributes to early identification of impaired left ventricular myocardial function in uremic patients with preserved left ventricular ejection fraction.

BACKGROUND:Cardiac damage is the leading cause of death in uremic patients. This study aimed to evaluate the application of non-invasive myocardial work index (NIMWI) by echocardiography in assessing the left ventricular (LV) systolic function in uremic patients.METHODS:Twenty-six uremic patients and 27 age- and sex-matched healthy volunteers were enrolled in the study. Except for the conventional echocardiographic parameters, the LV myocardial work (MW) parameters including GWI (myocardial global work index), GCW (global constructive work), GWW (global wasted work), and GWE (global work efficiency) were calculated in study participants. Differences in MW parameters between the uremic and normal groups were compared by independent-sample t-test. Receiver operating characteristic (ROC) curves were constructed for MW parameters to detect abnormal LV systolic function in uremic patients.RESULTS:Compared with the normal group, GWW was significantly increased and GWE decreased in the uremic group (P < 0.05). Area under the curve (AUC) for GWE by the ROC analysis was 0.966. The best threshold, sensitivity and specificity values of GWE to detect abnormality of LV systolic function in uremic patients were 92.5%, 0.89 and 0.96, respectively.CONCLUSIONS:NIMWI may be applied to assess the global MW of uremic patients. The presence of reduced GWE can help identify impaired left ventricular myocardial function in uremic patients with preserved LV ejection fraction with a high sensitivity and specificity.

Quantitative Analysis of Myocardial Work by Non-invasive Left Ventricular Pressure-Strain Loop in Patients With Type 2 Diabetes Mellitus.

Background: Type 2 diabetes mellitus (T2DM) is a common risk factor for cardiovascular diseases. The aims of this study were to evaluate the changes in the left ventricular myocardial work in T2DM patients using the left ventricular pressure-strain loop (PSL) technique, and to explore the risk factors for the left ventricular myocardial work impairment. Methods: Fifty patients with T2DM and 50 normal controls (NCs) were included in the study. In addition to conventional echocardiography and two-dimensional speckle tracking echocardiography, the left ventricular myocardial work parameters were measured using PSL technology. Results: The absolute value for global longitudinal strain (GLS), global work index (GWI) and, global constructive work (GCW) were significantly decreased in the T2DM group (P < 0.05), while the left ventricular ejection fraction (LVEF) was not significantly different between the T2DM and NC groups. Multivariable linear regression analysis showed that hemoglobin A1c (HbA1c) was independently related to GWI (β = -0.452, P < 0.05), while HbA1c and the diabetes duration were independently related to GCW (β = -0.393, P < 0.05 and β = -0.298, P < 0.05, respectively). Conclusions: Changes in the left ventricular myocardial systolic function in T2DM patients were identified using PSL technology. HbA1c was shown to be an independent risk factor affecting GWI, while HbA1c and diabetes duration were demonstrated to be independent risk factors affecting GCW.

Analysis of left ventricular diastolic energy loss in patients with aortic stenosis with preserved ejection fraction by using vector flow mapping.

Interaction effect of hypertension and obesity on left atrial phasic function: a three-dimensional echocardiography study.

Background:Hypertension (HT) and obesity often coexist and contribute to left atrial (LA) dysfunction. The present study aimed to compare LA function in hypertensive individuals and control participants with different body mass index (BMI) categories and to explore whether there is an interaction effect between HT and obesity on LA function.Methods:In this cross-sectional study, a total of 258 individuals (145 hypertensive and 113 non-hypertensive patients) were prospectively enrolled from Fuwai Central China Cardiovascular Hospital from September 2020 to November 2021. Hypertensive and non-hypertensive patients were both divided into three study subgroups (n=35 per group) according to their BMI: normal weight (BMI 18.5-<25 kg/m2), overweight (BMI 25-<30 kg/m2), and obesity (BMI ≥30 kg/m2) groups. LA volume and strain parameters were obtained using three-dimensional echocardiography.Results:A significant interaction effect between HT and obesity on LA function was observed [PInteraction =0.04, 0.03, 0.005, 0.01, and 0.002 for LA ejection fraction (LAEF), LA passive ejection fraction (LAPEF), LA active ejection fraction (LAAEF), LA reservoir longitudinal strain (LASr), and LA contraction longitudinal strain (LASct), respectively; PInteraction <0.001 for LA conduit longitudinal strain (LAScd)]. Univariate correlation analysis revealed that HT [LASr, r=-0.53, 95% confidence interval (CI): -0.62 to -0.42, P<0.001; LAScd, r=-0.49, 95% CI: -0.58 to -0.39, P<0.001; and LASct, r=-0.46, 95% CI: -0.55 to -0.34, P<0.001] and BMI categories (LASr, r=-0.68, 95% CI: -0.75 to -0.61, P<0.001; LAScd, r=-0.47, 95% CI: -0.57 to -0.35, P<0.001; and LASct, r=-0.73, 95% CI: -0.78 to -0.66, P<0.001) were negatively correlated with LA strains. A generalized linear model further demonstrated that there was an interaction effect between HT and obesity on LA strains after adjusting for confounding factors (Model 2: LASr, βHT*Obesity =-1.91, 95% CI: -3.48 to -0.35, P=0.01; LAScd, βHT*Obesity =-3.26, 95% CI: -4.83 to -1.70, P<0.001; LASct, βHT*Overweight =-1.97, 95% CI: -3.03 to -0.91, P<0.001; βHT*Obesity =-1.54, 95% CI: -2.67 to -0.41, P=0.007).Conclusions:Both HT and increasing BMI category had an adverse effect on LA function. The coexistence of HT and obesity further impaired LA performance in an interaction manner. Weight loss is essential to reduce the incidence of adverse cardiovascular events in hypertensive patients.

Interaction effect of type 2 diabetes mellitus and hypertension on left atrial function: a three-dimensional echocardiography study.

Background:Type 2 diabetes mellitus (T2DM) and hypertension (HT) often coexist and contribute to left atrial (LA) functional abnormalities. The aim of the present study was to explore whether there is a potential interaction effect between T2DM and HT on LA function.Methods:A total of 135 patients (45 with T2DM only, 45 with HT only, and 45 with both T2DM and HT) were enrolled and compared to 45 age- and sex-matched controls. LA volume fraction, including LA ejection fraction (LAEF), LA expansion index (LAEI), LA passive emptying fraction (LAPEF), and LA active emptying fraction (LAAEF), and strain parameters, including LA reservoir longitudinal strain (LASr), LA conduit longitudinal strain (LAScd), and LA contraction longitudinal strain (LASct), were obtained using three-dimensional echocardiography (3DE).Results:Patients with T2DM had significantly more impaired LA reservoir and conduit functions compared to those without T2DM (P<0.05), and patients with HT had a significantly more impaired LA reservoir function, conduit function, and booster pump function compared to those without HT (P<0.05). Two-way analysis of variance showed that there were significant additive interaction effects between T2DM and HT with respect to LASr (PT2DM + HT =0.002) and LAScd (PT2DM + HT =0.001). Generalized linear model demonstrated that T2DM + HT had a greater relative contribution than either T2DM or HT alone to the LA strain indexes, even after adjustment for other confounders (LASr, βT2DM + HT =-3.931, 95% CI: -6.237 to -1.624, P=0.001; LAScd, βT2DM + HT=-3.781, 95% CI: -5.653 to -1.908, P<0.001).Conclusions:Both T2DM and HT had an adverse effect on LA function. The coexistence of both conditions further impaired LA performance in an additive interaction fashion.

Evaluation of myocardial work in patients with hypertrophic cardiomyopathy and hypertensive left ventricular hypertrophy based on non-invasive pressure-strain loops.

Background:The capacity to distinguish hypertrophic cardiomyopathy (HCM) from hypertensive left ventricular hypertrophy (H-LVH) based on morphological features obtained by conventional echocardiography is limited. We investigated the global myocardial work of the left ventricle in two types of hypertrophies using the non-invasive myocardial work index (NMWI).Methods:Conventional echocardiography was performed on 107 subjects with preserved left ventricular ejection fraction (LVEF ≥ 50%), who comprised patients with HCM (n = 40), H-LVH (n = 35), and healthy people with normal blood pressure and left ventricular structure (n = 32). Except for the conventional echocardiographic parameters, the left ventricular myocardial work parameters based on pressure-strain loops, including global myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE), were evaluated in three groups. Multivariate discriminant analysis and receiver operating characteristic (ROC) curve were used to evaluate the incremental value of NMWI for distinguishing HCM from H-LVH.Results:Compared to the control group, GWI and GCW were significantly lower in HCM patients (P < 0.05), whereas GWI was significantly higher in H-LVH patients. GWW was higher and GWE was significantly decreased in both HCM and H-LVH patients than in the control group (P < 0.05). Multivariate discriminant analysis and ROC curve revealed that the inter-ventricular septum thickness (IVST)/left ventricular posterior wall thickness (LVPWT) and GCW were each able to distinguish HCM from H-LVH. The combination of IVST/LVPWT and GCW discriminated HCM and H-LVH with a higher predictive accuracy of 94.7%.Conclusion:NMWI may provide additional information in evaluating the myocardial function in patients with HCM and H-LVH. Myocardial work combined with conventional echocardiography could improve the clinical diagnostic accuracy of distinguishing HCM and H-LVH.

Non-invasive myocardial work index contributes to early identification of impaired left ventricular myocardial function in uremic patients with preserved left ventricular ejection fraction.

BACKGROUND:Cardiac damage is the leading cause of death in uremic patients. This study aimed to evaluate the application of non-invasive myocardial work index (NIMWI) by echocardiography in assessing the left ventricular (LV) systolic function in uremic patients.METHODS:Twenty-six uremic patients and 27 age- and sex-matched healthy volunteers were enrolled in the study. Except for the conventional echocardiographic parameters, the LV myocardial work (MW) parameters including GWI (myocardial global work index), GCW (global constructive work), GWW (global wasted work), and GWE (global work efficiency) were calculated in study participants. Differences in MW parameters between the uremic and normal groups were compared by independent-sample t-test. Receiver operating characteristic (ROC) curves were constructed for MW parameters to detect abnormal LV systolic function in uremic patients.RESULTS:Compared with the normal group, GWW was significantly increased and GWE decreased in the uremic group (P < 0.05). Area under the curve (AUC) for GWE by the ROC analysis was 0.966. The best threshold, sensitivity and specificity values of GWE to detect abnormality of LV systolic function in uremic patients were 92.5%, 0.89 and 0.96, respectively.CONCLUSIONS:NIMWI may be applied to assess the global MW of uremic patients. The presence of reduced GWE can help identify impaired left ventricular myocardial function in uremic patients with preserved LV ejection fraction with a high sensitivity and specificity.

Quantitative Analysis of Myocardial Work by Non-invasive Left Ventricular Pressure-Strain Loop in Patients With Type 2 Diabetes Mellitus.

Background: Type 2 diabetes mellitus (T2DM) is a common risk factor for cardiovascular diseases. The aims of this study were to evaluate the changes in the left ventricular myocardial work in T2DM patients using the left ventricular pressure-strain loop (PSL) technique, and to explore the risk factors for the left ventricular myocardial work impairment. Methods: Fifty patients with T2DM and 50 normal controls (NCs) were included in the study. In addition to conventional echocardiography and two-dimensional speckle tracking echocardiography, the left ventricular myocardial work parameters were measured using PSL technology. Results: The absolute value for global longitudinal strain (GLS), global work index (GWI) and, global constructive work (GCW) were significantly decreased in the T2DM group (P < 0.05), while the left ventricular ejection fraction (LVEF) was not significantly different between the T2DM and NC groups. Multivariable linear regression analysis showed that hemoglobin A1c (HbA1c) was independently related to GWI (β = -0.452, P < 0.05), while HbA1c and the diabetes duration were independently related to GCW (β = -0.393, P < 0.05 and β = -0.298, P < 0.05, respectively). Conclusions: Changes in the left ventricular myocardial systolic function in T2DM patients were identified using PSL technology. HbA1c was shown to be an independent risk factor affecting GWI, while HbA1c and diabetes duration were demonstrated to be independent risk factors affecting GCW.

Analysis of left ventricular diastolic energy loss in patients with aortic stenosis with preserved ejection fraction by using vector flow mapping.