Cardiac structure and function before and after bariatric surgery: a clinical overview

Bariatric surgery mitigated electrocardiographic abnormalities in patients with morbid obesity

Obesity can lead to cardiovascular dysfunctions and cause electrocardiographic disruptions. Bariatric surgery plays a significant role in weight loss. To assess its benefits, this study investigated electrocardiographic changes before and after bariatric surgery. The present article describes a retrospective cohort study with a 6-month follow-up period. Electrocardiograms were interpreted and compared before and six months after surgery. The relationships between weight loss, type of surgery, and electrocardiographic alterations were analyzed. A total of 200 patients participated in the study, with 34 (17%) men and 166 (83%) women. The mean age of the participants was 44.6 ± 8.6, and their mean body mass index was 43.8 ± 5.5 kg/m2. The mean of QTc decreased after the surgery, while the Sokolow-Lyon scores increased. The statistical analysis showed that QTc dispersion (> 40) (P < 0.001), right ventricular hypertrophy (P < 0.001), abnormal R wave progression (P < 0.001), QTc (P < 0.001) and Sokolow-Lyon criteria (P < 0.001) significantly changed postoperatively. In conclusion, bariatric surgery can reduce QTc, correct poor R wave progression, and resolve right ventricular hypertrophy (RVH) in patients with morbid obesity.

The effects of bariatric surgery on cardiac function: a systematic review and meta-analysis

INTRODUCTION

Obesity is associated with alterations in cardiac structure and haemodynamics leading to cardiovascular mortality and morbidity. Culminating evidence suggests improvement of cardiac structure and function following bariatric surgery.

OBJECTIVE

To evaluate the effect of bariatric surgery on cardiac structure and function in patients before and after bariatric surgery.

METHODS

Systematic review and meta-analysis of studies reporting pre- and postoperative cardiac structure and function parameters on cardiac imaging in patients undergoing bariatric surgery.

RESULTS

Eighty studies of 3332 patients were included. Bariatric surgery is associated with a statistically significant improvement in cardiac geometry and function including a decrease of 12.2% (95% CI 0.096-0.149; p < 0.001) in left ventricular (LV) mass index, an increase of 0.155 (95% CI 0.106-0.205; p < 0.001) in E/A ratio, a decrease of 2.012 mm (95% CI 1.356-2.699; p < 0.001) in left atrial diameter, a decrease of 1.16 mm (95% CI 0.62-1.69; p < 0.001) in LV diastolic dimension, and an increase of 1.636% (95% CI 0.706-2.566; p < 0.001) in LV ejection fraction after surgery.

CONCLUSION

Bariatric surgery led to reverse remodelling and improvement in cardiac geometry and function driven by metabolic and haemodynamic factors.

Effect of bariatric surgery on maternal cardiovascular system

OBJECTIVE

Bariatric surgery is a successful treatment for sustainable weight loss and has been associated with improvement in cardiovascular function. Pregnancy after bariatric surgery is becoming increasingly common; however, little is known about the maternal cardiovascular system postsurgery. The aim of this study was to investigate maternal cardiovascular adaptation to pregnancy in women with previous bariatric surgery, compared with that in women with no history of weight-loss surgery and an early-pregnancy body mass index (BMI) similar to the presurgery BMI of the postbariatric women.

METHODS

This was a prospective, observational, longitudinal study conducted from April 2018 to June 2020 including 30 pregnant women who had undergone bariatric surgery and 30 who had not, matched for presurgery BMI. Participants were seen at three timepoints during pregnancy: 12-14, 20-24 and 30-32 weeks' gestation. At all visits, maternal blood pressure (BP) was measured and cardiac geometry and function were assessed using two-dimensional (2D) transthoracic echocardiography. On a subset of patients (15 in each group), 2D speckle tracking was performed to assess global longitudinal and circumferential strain. Offline analysis was performed, and multilevel linear mixed-effects models were used for all comparisons.

RESULTS

Compared with the no-surgery group, and across all trimesters, pregnant women with previous bariatric surgery had lower BP, heart rate and cardiac output and higher peripheral vascular resistance (P < 0.01 for all). Similarly, the postbariatric group demonstrated more favorable cardiac geometry and diastolic indices, including lower left ventricular mass, left atrial volume and relative wall thickness, together with higher E-wave/A-wave flow velocity across the mitral valve and higher mitral velocity (E') at the lateral and medial annulus on tissue Doppler imaging (P < 0.01 for all). There was no difference in ejection fraction, although global longitudinal strain was lower in postbariatric women (P < 0.01), indicating better systolic function.

CONCLUSION

Our findings indicate better maternal cardiovascular adaptation in women with previous bariatric surgery compared with presurgery BMI-matched pregnant women with no history of weight-loss surgery. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

The Impact of Bariatric Surgery on Cardiac Structure, and Systolic and Diastolic Function in Patients with Obesity: A Systematic Review and Meta-analysis

The purpose of this study was to provide pooled data from all studies on the impact of bariatric surgery on cardiac structure, and systolic and diastolic function evaluated by either echocardiography or cardiac magnetic resonance. PubMed, Web of Science, Embase, and Scopus databases were searched. Almost all of cardiac left-side structural indices improved significantly after bariatric surgery. However, right-side structural indices did not change significantly. Left ventricular ejection fraction and most of the diastolic function indices improved significantly after the bariatric surgery. The subgroup analysis showed that the left ventricular mass index decreased more in long-term follow-up (≥ 12 months). In addition, subgroup analysis of studies based on surgery type did not reveal any difference in outcomes between gastric bypass and sleeve gastrectomy groups.

The effects of glucagon like peptide-1 (GLP-1) on cardiac remodeling: exploring the role of medication and physiological modulation after metabolic surgery

Obesity and associated comorbidities reach epidemic proportions nowadays. Several treatment strategies exist, but bariatric surgery has the only longstanding effects. Since a few years, there is increasing interest in the effects of gastro-intestinal hormones, in particular Glucagon-Like Peptide-1 (GLP-1) on the remission of Type 2 Diabetes (T2DM) and its effects on cardiac cardiovascular morbidity, cardiac remodeling, and mortality. In the past years several high quality multicenter randomized controlled trials were developed to assess the effects of GLP-1 receptor agonist therapy on cardiovascular morbidity and mortality. Most of the trials were designed and powered as non-inferiority trials to demonstrate cardiovascular safety. Most of these trials show a reduction in cardiovascular morbidity in patients with T2DM. Some follow-up studies indicate potential beneficial effects of GLP-1 receptor agonists on cardiovascular function in patients with heart failure, however the results are contradictory, and we need long-term studies to make firm conclusions about the pleiotropic properties of incretin-based therapies. However, it seems that GLP-1 receptor agonists have different effects than the increased GLP-1 production after bariatric surgery on cardiovascular remodeling. One of the hypotheses is that the blood concentrations of GLP-1 receptor agonists are three times higher compared to GLP-1 increase after bariatric and metabolic surgery. The purpose of this narrative review is to summarize the effects of GLP-1 on cardiovascular morbidity, mortality and remodeling due to medication but also due to bariatric and metabolic surgery. The second objective is to explain the possible differences in effects of GLP-1 agonists and bariatric and metabolic surgery.

Bariatric Surgery Improves Heart Geometry and Plasticity

BACKGROUND

Obesity is commonly associated with increased sympathetic tone, changes in heart geometry, and mortality. The aforementioned translates into a higher and potentially modifiable mortality risk for this specific population.

OBJECTIVES

The aim of the study was to analyze the extent of changes in the heart ventricular structure following rapid weight loss after bariatric surgery.

SETTING

Academic, university-affiliated hospital.

METHODS

We retrospectively reviewed all the patients that underwent bariatric surgery at our institution between 2010 and 2015. Data analyzed included demographics, BMI, and associated medical problems. Preoperative and postoperative echography readings were compared looking at the heart geometry, cardiac volumes, and wall thickness.

RESULTS

Fifty-one patients who had bariatric surgery and had echocardiography before and after the surgery were identified. There were 33 females (64.7%). The mean age was 63.4 ± 12.0 years with an average BMI of 40.3 ± 6.3. The mean follow-up was 1.2 years after the procedure. At 1 year follow-up 25 patients (49%, p = 0.01) showed normal left ventricular geometry. The left ventricular mass (229 ± 82.1 vs 193.2 ± 42.5, p<0.01) and the left ventricular end diastolic volume (129.4 ± 53 vs 96.4 ± 36.5, p = 0.01) showed a significant modification following the procedure. There was a significant improvement in the interventricular septal thickness (p = 0.01) and relative wall thickness (p < 0.01) following surgery.

CONCLUSION

The patients with obesity present a significant cardiac remodeling from concentric remodeling to normal geometry after bariatric surgery. The decrease in BMI has a direct effect on improvement of the left ventricular structure. Further studies must be carried out to define the damage of obesity to diastolic function.

Maternal cardiovascular adaptation to pregnancy in women with previous bariatric surgery

BACKGROUND

Obesity in pregnancy is associated with substantial risks, notably hypertensive disorders. Bariatric surgery achieves sustained weight loss and has several cardiovascular benefits, including positive effects on blood pressure, cardiac geometry, and both systolic and diastolic function. Pregnancy following bariatric surgery is also associated with improved outcomes, including a reduced risk of hypertensive disorders. The underlying mechanisms, however, remain uncertain. Maternal cardiovascular adaptation plays a vital role in maintaining a healthy pregnancy, and maladaptation has been associated with adverse pregnancy outcomes. However, to date, the maternal cardiovascular adaptation to pregnancy after bariatric surgery has not been investigated.

OBJECTIVE

To investigate the maternal cardiovascular adaptation to pregnancy in women with previous bariatric surgery compared with women with a similar early-pregnancy body mass index, age, and race but no history of weight loss surgery.

STUDY DESIGN

This was a prospective, observational, longitudinal study including pregnant women with (n=41) and without (n=41) a history of bariatric surgery. The participants were seen at 3 time points; at 12 to 14, 20 to 24, and 30 to 32 weeks of pregnancy. At each visit, the blood pressure was measured and the maternal cardiovascular system was assessed using transthoracic echocardiography. Two-dimensional speckle tracking was performed to assess the global longitudinal and circumferential strain on a subset of patients (15 in each group). Offline analysis was performed according to the European and American echocardiography guidelines. Multilevel linear mixed-effect models were used for all the comparisons.

RESULTS

Compared with the no-surgery group, women with previous bariatric surgery, had lower systolic and diastolic blood pressure, heart rate, and cardiac output across all the trimesters (P<.01 for all comparisons), with an evidence of more favorable diastolic indices, including a higher E-wave/A-wave ratio across the mitral valve (P<.001), higher mitral velocity at the lateral and medial annulus (E') (P=.01 and P=.03, respectively), and a lower left atrial volume (P<.05). Furthermore, women with previous bariatric surgery demonstrated lower global longitudinal (P<.01) and circumferential strain (P=.02), which is suggestive of better systolic function.

CONCLUSION

Our findings indicate better cardiovascular adaptation to pregnancy in women with previous bariatric surgery than in pregnant women of a similar early-pregnancy body mass index but no history of surgery.

Parallel improvement of systolic function with surgical weight loss in patients with heart failure and reduced ejection fraction: a systematic review and patient-level meta-analysis

BACKGROUND

Morbid obesity (MO) is an increasingly common condition in patients with heart failure with reduced ejection fraction (HFrEF). Although substantial weight loss in morbidly obese patients has proved to slow the progression of heart failure, parallel alteration of ejection fraction (EF) and New York Heart Association (NYHA) functional class along with post-bariatric surgery weight loss is yet to be determined.

OBJECTIVES

This systematic review aimed to measure the effect of bariatric weight loss on EF and NYHA functional class in patients with HFrEF.

METHODS

A systematic literature review was performed in Medline/PubMed to identify studies in patients with MO and pre-existing HFrEF, who underwent bariatric surgery.

RESULTS

A total of 11 studies encompassing 136 patients with HFrEF undergoing bariatric surgery for MO were included. Six studies provided patient-level data on 37 cases. Patients lost an average body mass index (BMI) of 12.9 ± 4.2 kg/m² (5.1 to 23 kg/m²) after an average follow up of 22.43 ± 18.6 months (2-89 mo). There was a direct correlation between BMI loss and EF improvement (r = 0.61, P < .0001), but not between BMI loss and NYHA functional class changes (r = 0.17, P = .4).

CONCLUSION

Weight loss induced by bariatric surgery results in parallel EF increase in patients with MO and HFrEF. However, current data does not indicate a parallel improvement of clinical symptoms (NYHA functional class) along with such an increase in EF in this population of patients.

Impact of exercise training after bariatric surgery on cardiometabolic risk factors: a systematic review and meta-analysis of controlled trials

The purpose of this systematic review was to provide updated evidence synthesis of the effectiveness of exercise training in patients with obesity undergoing bariatric surgery to improve cardio-metabolic risk. We systematically searched the MEDLINE, EMBASE, Scopus, Cochrane, and Web of Science databases. The studies selected were those in which an exercise-based intervention was performed after bariatric surgery, a control group was present, and at least one of the following outcomes was investigated: VO_2max or VO_2peak, resting heart rate (RHR), blood pressure, lipid profile, glucose, and insulin. The study quality was assessed using the PEDro scale and the data were meta-analyzed with a random effects model, comparing control groups to intervention groups using standardized measurements. Twenty articles were included in the systematic review and fourteen (70%) in the meta-analysis. Significant differences were observed between the control and intervention groups (always in favor of exercise) for absolute VO_2max / VO_2peak (ES = 0.317; 95% CI = 0.065, 0.569; p = 0.014), VO_2max / peak relative to body weight (ES = 0.673; 95% CI = 0.287, 1.060; p = 0.001), HDL cholesterol (ES = 0.22; 95% CI = 0.009, 0.430; p = 0.041) and RHR (ES = -0.438; 95% CI = -0.753, -0.022; p = 0.007). No effects were observed for either systolic or diastolic blood pressure. Exercise training for patients undergoing bariatric surgery appears to be effective in improving absolute and relative VO_2max / VO_2peak, HDL cholesterol and reducing the RHR. More intervention studies using (better) exercise interventions are needed before discarding their effects on other cardiometabolic risk factors. This systematic review and meta-analysis has been registered in Prospero (CRD42020153398).

Regional adiposity, cardiorespiratory fitness, and left ventricular strain: an analysis from the Dallas Heart Study

BACKGROUND

Low cardiorespiratory fitness (CRF), high body mass index, and excess visceral adiposity are each associated with impairment in left ventricular (LV) peak circumferential strain (Ecc), an intermediate phenotype that precedes the development of clinical heart failure (HF). However, the association of regional fat distribution and CRF with Ecc independent of each other and other potential confounders is not known.

METHODS

Participants from the Dallas Heart Study Phase 2 who underwent dual energy X-ray absorptiometry assessment of regional fat distribution, CRF assessment by submaximal treadmill test, and Ecc quantification by tissue-tagged cardiovascular magnetic resonance were included in the analysis. The cross-sectional associations of measures of regional adiposity, namely visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and lower-body fat (LBF) with Ecc after adjustment for CRF and other potential confounders (independent variables) were assessed using multivariable linear regression analysis.

RESULTS

The study included 1089 participants (55% female, 39% black). In the unadjusted analysis, higher VAT was associated with greater impairment in Ecc. After adjustment for baseline risk factors, CRF, parameters of LV structure and function, and other fat depots such as SAT and LBF, higher VAT remained associated with greater impairment in Ecc (β: 0.19, P = 0.002). SAT and LBF were not significantly associated with Ecc, however, CRF remained associated with Ecc in the fully adjusted model including all fat depots (β: - 0.15, P < 0.001).

CONCLUSIONS

VAT and CRF are each independently associated with impairment in Ecc, suggesting that higher VAT burden and low CRF mediate pathological cardiac remodeling through distinct mechanisms.

Effects of Bariatric Surgery on Heart Rhythm Disorders: a Systematic Review and Meta-Analysis

The aim of this systematic review is to provide an overview of the literature on the effects of bariatric surgery on obesity-associated electrocardiogram (ECG) abnormalities and cardiac arrhythmias. Fourteen studies were included with a methodological quality ranging from poor to good. Majority of the studies showed a significant decrease of QT interval and related measures after bariatric surgery. Seven studies were included in the meta-analysis on effects of bariatric surgery on QTc interval and a significant decrease in QTc interval of - 33.6 ms, 95%CI [- 49.8 to - 17.4] was seen. Bariatric surgery results in significant decrease in QTc interval and P-wave dispersion, i.e., a normalization of initial pathology. The effects on atrial fibrillation are conflicting and not yet fully understood.

Characteristics and resolution of hypertension in obese African American bariatric cohort

Weight reduction continues to be first-line therapy in the treatment of hypertension (HTN). However, the long-term effect of bariatric malabsorptive surgical techniques such as Roux-en-Y Gastric Bypass (RYGB) surgery in the management of hypertension (HTN) is less clear. African Americans (AA) are disproportionately affected by obesity and hypertension and have inconsistent outcomes after bariatric surgery (BS). Despite a plethora of bariatric literature, data about characteristics of a predominantly AA bariatric hypertensive cohort including hypertension in obese (HIO) are scarce and underreported. The aims of this study were, (1) to describe the preoperative clinical characteristics of HIO with respect to HTN status and age, and (2) to identify predictors of HTN resolution one year after RYGB surgery in an AA bariatric cohort enrolled at the Howard University Center for Wellness and Weight Loss Surgery (HUCWWS). In the review of 169 AA bariatric patients, the average BMI was 48.50 kg/m² and the average age was 43.86 years. Obese hypertensive patients were older (46 years vs. 37.89 years; p < .0001); had higher prevalence of diabetes mellitus (DM, 43.09% vs. 10.87%; p < .0001) and dyslipidemia (38.2% vs. 13.04%; p 0.002). Hypertensive AA who were taking ≥ 2 antihypertensive medications prior to RYGB were 18 times less likely to experience HTN resolution compared to hypertensive AA taking 0–1 medications, who showed full or partial response. Also, HIO was less likely to resolve after RYGB surgery in patients who needed ≥ 2 antihypertensive medications prior to surgical intervention.

Assessment of Carotid Artery Distensibility and Elasticity After Laparoscopic Sleeve Gastrectomy: a Prospective Study

PURPOSE

Although it is well known that obesity increases the risk of atherosclerosis in carotid arteries, it is not clear whether this risk changes after obesity surgery. The aim of this study was to investigate whether weight reduction with a laparoscopic sleeve gastrectomy (LSG) has any effect on distensibility and elasticity which show subclinical atherosclerosis in the carotid arteries of obese individuals.

MATERIALS AND METHODS

This prospective study included 130 patients (body mass index (BMI) 48.21 ± 6.97 kg/m²) who underwent LSG. The patients were followed up for 1 year. Comparisons were made of the distensibiliy and elasticity values calculated preoperatively and at 1, 3, 6, and 12 months, postoperatively.

RESULTS

There was a statistically significant increase in distensibility and elasticity values from baseline to 1, 3, 6, and 12 months postoperatively (p < 0.001 for both comparisons). The multiple linear regression analysis was used to find the variables affecting both distensibility and elasticity. According to the results, the presence of BMI decreases distensibility percentage change level by 0.38 units (β= - 0.38, 95% CI - 0.51;- 0.25, p < 0.001). The presence of fasting plasma glucose decreases elasticity percentage change level by 0.20 units. (β= - 0.20, 95% CI - 0.39; - 0.01, p = 0.037).

CONCLUSION

Carotid artery distensibility and elasticity values increase after LSG, and this change could be caused by the change in metabolic parameters and heart geometry. These results may indirectly suggest that subclinical atherosclerosis in carotid arteries has decreased after obesity surgery.

Overweight and obesity are associated with cardiac adverse structure remodeling in Chinese elderly with hypertension

There is limited information on the association of overweight and obesity with cardiac remodeling in elderly population. Therefore, we investigated whether overweight and obesity are associated with cardiac geometric structures and function in Chinese elderly. A total of 1183 hospitalized patients (aged 65–99 years) with primary hypertension were collected retrospectively in a cross-sectional study, and divided into underweight, normal weight, overweight and obesity patient groups according to their body mass index (BMI). Cardiac echocardiographic parameters were compared between the groups. BMI was 17.2 ± 1.2, 21.4 ± 1.2, 25.1 ± 1.2, 30.2 ± 2.6 kg/m² in underweight, normal weight, overweight and obesity groups respectively. Aortic and left atrial diameter, interventricular septal and left ventricular (LV) posterior wall thickness, LV end-diastolic and end-systolic diameter, and indexed LV mass, and prevalence of E/A reversal were higher, while LV ejection fraction and fractional shortening were lower in elderly with overweight or obesity, as compared with whose with underweight or normal weight separately (All P < 0.05). However, multivariable regression analysis showed that overweight and obesity are independently related to increased LV wall thickness, end-diastolic diameter and mass (All P < 0.05). In conclusions, this study demonstrates that overweight and obesity are associated with increased LV wall thickness, end-diastolic diameter and mass in Asian elderly.

Cardiac remodeling in obesity and after bariatric and metabolic surgery; is there a role for gastro-intestinal hormones?

Introduction: Obesity is associated with various diseases such as type 2 diabetes, hypertension, obstructive sleep apnea syndrome (OSAS), metabolic syndrome, and cardiovascular diseases. It affects several organ systems, including the pulmonary and cardiac systems. Furthermore, it induces pulmonary and cardiac changes that can result in right and/or left heart failure.Areas covered: In this review, authors provide an overview of obesity and cardiovascular remodeling, the individual actions of the gut hormones (like GLP-1 and PYY), the effects after bariatric/metabolic surgery and its influence on cardiac remodeling. In this review, we focussed and searched for literature in Pubmed and The Cochrane library (from the earliest date until April 2019), regarding cardiac function changes before and after bariatric surgery and literature regarding changes in gastrointestinal hormones.Expert opinion: Regarding the surgical treatment of obesity and metabolic diseases there is recognition of the importance of both weight loss (bariatric surgery) and improvement in metabolic milieu (metabolic surgery). A growing body of evidence further suggests that bariatric surgical procedures [like the Sleeve Gastrectomy (SG), Roux-en Y Gastric Bypass (RYGB), or One Anastomosis Gastric Bypass (OAGB)] have can improve outcomes of patients suffering from a number of cardiovascular diseases, including heart failure.