Bariatric Surgery and Myocardial Mechanics: A Meta-Analysis of Speckle Tracking Echocardiographic Studies

Cardioprotective benefits of metabolic surgery and GLP-1 receptor agonist-based therapies

Individuals with excessive adipose tissue and type 2 diabetes mellitus (T2DM) face a heightened risk of cardiovascular morbidity and mortality. Metabolic surgery is an effective therapy for people with severe obesity to achieve significant weight loss. Additionally, metabolic surgery improves blood glucose levels and can lead to T2DM remission, reducing major adverse cardiovascular outcomes (MACE). Glucagon-like peptide 1 (GLP-1) receptor agonists (GLP-1RAs) are a class of medication that effectively reduce body weight and MACE in patients with T2DM. This review explores the potential mechanisms underlying the cardioprotective benefits of metabolic surgery and GLP-1RA-based therapies and discusses recent evidence and emerging therapies in this dynamic area of research.

Left ventricular systolic dysfunction in obesity: a meta-analysis of speckle tracking echocardiographic studies

BACKGROUND

Obesity is a risk factor for left ventricular hypertrophy (LVH) and diastolic dysfunction. Available evidence on impaired myocardial deformation in obese patients without apparent systolic dysfunction assessed by LV ejection fraction (LVEF) is based on single studies. The aim of the present meta-analysis was to provide a comprehensive and updated information on this issue.

METHODS

The PubMed, OVID-MEDLINE, and Cochrane library databases were analysed to search English-language articles published from the inception up to 31 December 2023. Studies were identified by using MeSH terms and crossing the following search items: ' myocardial strain', 'left ventricular mechanics', 'longitudinal global strain', 'speckle tracking echocardiography', 'systolic dysfunction', 'left ventricular ejection fraction', and 'obesity'.

RESULTS

Twenty-four studies including 5792 obese and 5518 nonobese individuals from different clinical settings were considered for the analysis. LV global longitudinal strain (GLS) was significantly impaired in the obese group [standard means difference (SMD): -0.86 ± 0.08; confidence interval (CI) -1.02 to -0.69, P  < 0.0001] and this was paralleled by a significant difference in pooled LVEF between obese and controls (SMD -0.27 ± 0.06; CI -0.40 to -0.15, P  < 0.0001). Unlike GLS, however, the majority of the selected studies failed to show statistically significant differences in LVEF. Furthermore, in patients with advanced obesity (BMI > 35 kg/m 2 , data from six studies), LV systolic dysfunction was more significantly detected by GLS (SMD -1.24 ± 0.19, CI -1.61/-0.87, P  < 0.0001) than by LVEF (SMD -0.54 ± 0.27, CI -1.07 to -0.01, P  = 0.046).

CONCLUSION

The present meta-analysis suggests that GLS may unmask systolic dysfunction often undetected by conventional LVEF in the obese setting; thus, this parameter should be incorporated into routine work-up aimed to identify obesity-mediated subclinical cardiac damage.

The effect of significant weight loss after bariatric surgery on echocardiographic indices: an observational study focusing on left ventricular deformation by 2D speckle echocardiography and right ventricular size

BACKGROUND

Obesity is a known risk factor for atherosclerosis and cardiac disease.

HYPOTHESIS

This study evaluated the effect of significant weight loss following bariatric surgery on myocardial deformation indices and right ventricular size (RV). This was a prospective cohort study. Morbid obese patients scheduled for bariatric surgery from July 2017 to February 2018 at Firoozgar Hospital were included in our study and referred for transthoracic echocardiography at Rajaie Cardiovascular Medical and Research Center.

RESULTS

Thirty-four patients entered the study. The absolute value of global longitudinal strain (GLS) at baseline, 3, and 6 months after surgery was 17.42 ± 2.94%, 18.24 ± 3.09%, and 19.52 ± 2.78%, respectively, with a statistically significant difference from baseline to after six months (P value < 0.001). The absolute value of global circumferential strain (GCS) at baseline, 3, and 6 months after surgery was 20.14 ± 4.22%, 23.32 ± 4.66%, and 24.53 ± 4.52%, respectively, with statistically significant changes (P value < 0.001) from baseline to three months and from baseline to six months and no significant difference from three months to six months. A significant decrease was reported in mechanical dispersion of circumferential strain (38.05 ± 23.81-23.37 ± 20.86 ms, P value = 0.006) 6 months after surgery. Right ventricular size three- and six-month post-surgery showed a significant decrease relative to baseline echocardiography.

CONCLUSIONS

Bariatric surgery could enhance cardiac function, as proven by 2D speckle echocardiography. Changes in RV size may be related to weight loss and should be considered when assessing patients who have undergone bariatric surgery.

The evaluation of bariatric surgery effect on cardiac structure and function using transthoracic echocardiography: a cohort study

BACKGROUND

Obesity is a pathology and a leading cause of death worldwide. Obesity can harm multiple organs, including the heart. In this study, we aim to investigate the effect of bariatric surgery and following weight loss on cardiac structure and functions using echocardiography parameters in patients with morbid obesity.

METHODS

In this cohort study, 30 patients older than 18 with BMI > 40 or BMI > 35 and comorbidity between March 2020 to March 2021 were studied. The patients underwent transthoracic echocardiography before and after six months of the bariatric surgery.

RESULTS

In total, 30 patients (28 women, 93.3%) with a mean age of 38.70 ± 9.19 were studied. Nine (30%) were diabetic, and 9 (30%) had hypertension. After six months of bariatric surgery, all physical measurements, including weight, Body mass index, and Body surface area, decreased significantly (p < 0.001). After bariatric surgery, all parameters regarding left ventricular morphology, including left ventricular mass, interventricular septal thickness, left ventricular posterior wall thickness, left ventricular end-systolic diameter, and left ventricular end-diastolic diameter, improved significantly (p < 0.001). Also, LVEF rose post-bariatric surgery (p < 0.001). TAPSE parameter indicating right ventricular function also improved (p < 0.001). Right ventricular diameter, left atrium volume, and mitral inflow E/e' decreased significantly (p < 0.001).

CONCLUSION

Systolic and diastolic parameters refine significantly after bariatric surgery in patients with obesity. Bariatric surgery lead to significant cardiac structure and function improvement.

Impact of Bariatric Surgery on Left Ventricular Structure and Function

BACKGROUND

Obesity leads to an increased risk of cardiovascular disease morbidity and death, including heart failure. Bariatric surgery has been proven to be the most effective long-term weight management treatment. This study investigated the changes in cardiac structure and function after bariatric surgery, including left ventricular global longitudinal strain.

METHODS AND RESULTS

There were 398 consecutive patients who underwent bariatric surgery with pre- and postoperative transthoracic echocardiographic imaging at a US health system between 2004 and 2019. We compared cardiovascular risk factors and echocardiographic parameters between baseline and follow-up at least 6 months postoperatively. Along with decreases in weight postoperatively, there were significant improvements in cardiovascular risk factors, including reduction in systolic blood pressure levels from 132 mm Hg (25th-75th percentile: 120-148 mm Hg) to 127 mm Hg (115-140 mm Hg; P=0.003), glycated hemoglobin levels from 6.5% (5.9%-7.6%) to 5.7% (5.4%-6.3%; P<0.001), and low-density lipoprotein levels from 97 mg/dL (74-121 mg/dL) to 86 mg/dL (63-106 mg/dL; P<0.001). Left ventricular mass decreased from 205 g (165-261 g) to 190 g (151-236 g; P<0.001), left ventricular ejection fraction increased from 58% (55%-61%) to 60% (55%-64%; P<0.001), and left ventricular global longitudinal strain improved from -15.7% (-14.3% to -17.5%) to -18.6% (-16.0% to -20.3%; P<0.001) postoperatively.

CONCLUSIONS

This study has shown the long-term impact of bariatric surgery on cardiac structure and function, with reductions in left ventricular mass and improvement in left ventricular global longitudinal strain. These findings support the cardiovascular benefits of bariatric surgery.

Impact of body mass index on worsening of diastolic function and impairment of left atrial strain in the general female urban population: a subanalysis of the Berlin female risk evaluation echocardiography follow-up study

Background

The association of body mass index (BMI) with diastolic dysfunction (DD) is well described in the literature. However, there is conflicting evidence and long-term follow-up data regarding effects of BMI on preclinical DD and left atrial (LA) function are scarce, highlighting the importance of early detection tools, such as myocardial strain.

Purpose

The aim of our study was to prospectively analyze the impact of clinical and demographic parameters, especially of BMI, on worsening of diastolic function and left atrial strain (LAS) in an urban population of women with a low prevalence of cardiovascular risk factors.

Methods and Results

An extensive clinical and echocardiographic assessment comprising the analysis of phasic LAS using two-dimensional speckle-tracking echocardiography (2D STE) was performed in 258 participants of the Berlin Female Risk Evaluation (BEFRI) trial between October 2019 and December 2020 after a mean follow-up period of 6.8 years. We compared clinical and echocardiographic parameters stratifying women by BMI < or ≥25 kg/m2, and we analyzed the impact of demographic characteristics on the worsening of DD and LA mechanics in the longer-term follow-up using univariate and multivariate regression analyses. 248 women were suitable for echocardiographic analysis of LAS using 2D STE. After a mean follow-up time of 6.8 years, LA reservoir strain (LASr) and LA conduit strain (LAScd) were significantly reduced in participants with a BMI ≥25 kg/m2 compared with women with a BMI <25 kg/m2 at baseline (30 ± 8% vs. 38 ± 9%, p < 0.0001; -14 ± 7% vs. -22 ± 8%, p < 0.0001). 28% of the overweighted women presented a deterioration of diastolic function at the time of follow-up in contrast with only 7% of the group with a BMI <25 kg/m2 (p < 0.0001). BMI remained significantly associated with LAS reductions after adjustment for other risk factors in multivariate regression analyses.

Conclusion

Overweight and obesity are related to impaired LAS and to a worsening of diastolic function after a long-term follow-up in a cohort of randomly selected women.