Early cardiac complications after bariatric surgery: does the type of procedure matter?

Impact of Bariatric Surgery on the Prevalence and Outcomes of Atrial Fibrillation in Obese Patients

Obesity has been identified as a significant factor contributing to the development of numerous cardiovascular conditions and as a result, the cardiovascular community has prioritized efforts to address obesity and reduce its associated risks. However, despite these efforts, the prevalence of obesity continues to rise steadily, and is projected to double in the upcoming years. Atrial fibrillation is among the most prevalent and extensively researched cardiovascular comorbidities associated with obesity. Several mechanisms have been postulated, including scar tissue formation and fat deposition, which ultimately leads to atrial remodeling and subsequent arrhythmogenesis. Numerous strategies have been implemented to prevent and manage obesity, encompassing lifestyle adjustments, dietary modifications, pharmacological treatments, and surgical interventions. Bariatric surgery has garnered significant recognition over the years due to its promising outcomes, including a decrease in the overall prevalence of atrial fibrillation and other cardiovascular comorbidities in general in obese patients. This study focuses on the current trends regarding the impact of bariatric surgery on obese patients with atrial fibrillation.

Machine learning prediction of major adverse cardiac events after elective bariatric surgery

BACKGROUND

Machine learning (ML) is an emerging technology with the potential to predict and improve clinical outcomes including adverse events, based on complex pattern recognition. Major adverse cardiac events (MACE) after bariatric surgery have an incidence of 0.1% but carry significant morbidity and mortality. Prior studies have investigated these events using traditional statistical methods, however, studies reporting ML for MACE prediction in bariatric surgery remain limited. As such, the objective of this study was to evaluate and compare MACE prediction models in bariatric surgery using traditional statistical methods and ML.

METHODS

Cross-sectional study of the MBSAQIP database, from 2015 to 2019. A binary-outcome MACE prediction model was generated using three different modeling methods: (1) main-effects-only logistic regression, (2) neural network with a single hidden layer, and (3) XGBoost model with a max depth of 3. The same set of predictor variables and random split of the total data (50/50) were used to train and validate each model. Overall performance was compared based on the area under the receiver operating curve (AUC).

RESULTS

A total of 755,506 patients were included, of which 0.1% experienced MACE. Of the total sample, 79.6% were female, 47.8% had hypertension, 26.2% had diabetes, 23.7% had hyperlipidemia, 8.4% used tobacco within 1 year, 1.9% had previous percutaneous cardiac intervention, 1.2% had a history of myocardial infarction, 1.1% had previous cardiac surgery, and 0.6% had renal insufficiency. The AUC for the three different MACE prediction models was: 0.790 for logistic regression, 0.798 for neural network and 0.787 for XGBoost. While the AUC implies similar discriminant function, the risk prediction histogram for the neural network shifted in a smoother fashion.

CONCLUSION

The ML models developed achieved good discriminant function in predicting MACE. ML can help clinicians with patient selection and identify individuals who may be at elevated risk for MACE after bariatric surgery.

Short-term cardiovascular events after bariatric surgery in patients with metabolic syndrome

BACKGROUND

Patients with metabolic syndrome (MetS) are at increased risk of developing cardiovascular disease along with other adverse events after bariatric surgery.

OBJECTIVES

The incidence of short-term major adverse cardiovascular events (MACE) in patients with MetS undergoing bariatric surgery is not well characterized.

SETTING

Accredited bariatric surgery centers in the United States and Canada.

METHODS

A total of 760,076 patients aged ≥18 years with body mass index ≥35 kg/m2 who underwent primary bariatric surgery between 2015 and 2018 were included. Patients with both diabetes and hypertension were described as the MetS cohort. Patient characteristics, operative technique, and 30-day outcomes were compared. The primary outcome was incidence of MACE, a composite of myocardial infarction, stroke, and all-cause mortality. Unadjusted and multivariable logistic regression analyses were performed and included an interaction between MetS and hyperlipidemia (HLD).

RESULTS

Of the 577,882 patients included, 111,128 (19.2%) exhibited MetS. Patients with MetS more frequently experienced MACE compared with patients without MetS (.3% versus .1%; P < .001). The odds of MACE were greater for patients with MetS versus Non-MetS (odds ratio [OR] 2.87; 95% CI, 2.49-3.32) in the unadjusted analysis. MetS without HLD, MetS with HLD, and Non-MetS with HLD are significantly associated with MACE when compared with those with non-MetS without HLD.

CONCLUSIONS

Patients with MetS have an increased frequency of cardiac events following bariatric surgery. Future studies should determine if optimization of 1 or more components of MetS or other related co-morbidities reduces the cardiovascular risk for patients.

Safety of bariatric surgery in the elderly: results from the Dutch National Registry

BACKGROUND

The increased human life expectancy and prevalence of obesity lead to more elderly people with obesity. As the popularity of bariatric surgery continues to grow, more elderly persons apply for bariatric surgery. However, because of the potentially higher surgical risk in elderly patients, bariatric surgery has been performed in small numbers. Moreover, the literature so far has shown controversial results.

OBJECTIVE

To determine the safety of bariatric surgery in elderly patients in terms of 2-year morbidity and mortality.

SETTING

Dutch nationwide mandatory registry for bariatric surgery.

METHODS

A population-based retrospective cohort study. Elderly patients (aged ≥65 years) who received primary bariatric surgery between January 2015 and January 2020 were compared with the general bariatric surgical population (aged 18-65 years).

RESULTS

Of 49,553 patients, 838 elderly patients (1.7%) were included. An intraoperative complication was registered in 1.2% of the elderly patients and 1.1% of the nonelderly patients (P = .814). A severe short-term complication (≤30 days) was registered in 38 elderly patients (4.5%) and 1071 nonelderly patients (2.2%) (P < .001). The short-term mortality rates were .2% and .1%, respectively (P = .173). Bleeding was the most reported short-term complication. Significantly more nonelderly patients had a follow-up visit; 560 elderly patients (66.8%) versus 34,975 nonelderly patients (71.8%) (P = .002). The severe midterm complication rate (>30 days to ≤2 years) was significantly higher in nonelderly patients (3.7% versus 1.6%; P = .008).

CONCLUSIONS

Bariatric surgery in elderly patients is safe in terms of perioperative outcome, mortality, and midterm complication rate. However, elderly patients experienced twice as many severe short-term complications. Bariatric surgery in elderly patients should be recommended on a case-by-case basis.

Selection of Robotic Bariatric Surgery Candidates: a Nationwide Analysis

INTRODUCTION

This study aims to identify risk factors associated with 30-day major complications, readmission, and delayed discharge for patients undergoing robotic bariatric surgery.

METHODS

From the metabolic and bariatric surgery and accreditation quality improvement program (2015-2018) datasets, adult patients who underwent elective robotic bariatric operations were included. Predictors for 30-day major complications, readmission, and delayed discharge (hospital stay ≥ 3 days) were identified using univariable and multivariable analyses.

RESULTS

Major complications in patients undergoing robotic bariatric surgery were associated with both pre-operative and intraoperative factors including pre-existing cardiac morbidity (OR = 1.41, CI = [1.09-1.82]), gastroesophageal reflux disease [GERD] (OR = 1.23, CI = [1.11-1.38]), pulmonary embolism (OR = 1.51, CI = [1.02-2.22]), prior bariatric surgery (OR = 1.66, CI = [1.43-1.94]), increased operating time (OR = 1.003, CI = [1.002-1.004]), gastric bypass or duodenal switch (OR = 1.58, CI = [1.40-1.79]), and intraoperative drain placement (OR = 1.28, CI = [1.11-1.47]). With regard to 30-day readmission, non-white race (OR = 1.25, CI = [1.14-1.39]), preoperative hyperlipidemia (OR = 1.16, CI = [1.14-1.38]), DVT (OR = 1.48, CI = [1.10-1.99]), therapeutic anticoagulation (OR = 1.48, CI = [1.16-1.89]), limited ambulation (OR = 1.33, CI = [1.01-1.74]), and dialysis (OR = 2.14, CI = [1.13-4.09]) were significantly associated factors. Age ≥ 65 (OR = 1.18, CI = [1.04-1.34]), female gender (OR = 1.21, CI = [1.10-1.32]), hypertension (OR = 1.08, CI = [1.01-1.15]), renal insufficiency (OR = 2.32, CI = [1.69-3.17]), COPD (OR = 1.49, CI = [1.23-1.82]), sleep apnea (OR = 1.10, CI = [1.03-1.18]), oxygen dependence (OR = 1.47, CI = [1.10-2.0]), steroid use (OR = 1.26, CI = [1.02-1.55]), IVC filter (OR = 1.52, CI = [1.15-2.0]), and BMI ≥ 40 (OR = 1.12, CI = [1.04-1.21]) were risk factors associated with delayed discharge.

CONCLUSION

When selecting patients for bariatric surgery, surgeons early in their learning curve for utilizing robotics should avoid individuals with pre-existing cardiac or renal morbidities, venous thromboembolism, and limited functional status. Patients who have had previous bariatric surgery or require technically demanding operations are at higher risk for complications. An evidence-based approach in selecting bariatric candidates may potentially minimize the overall costs associated with adopting the technology.

Effect of high-risk factors on postoperative major adverse cardiovascular and cerebrovascular events trends following bariatric surgery in the United States from 2012 to 2019

BACKGROUND

Recent examination of trends in postoperative major adverse cardiovascular and cerebrovascular events (MACE) following bariatric surgery, including accredited and nonaccredited centers, and the factors affecting those trends, is lacking.

OBJECTIVES

The objective of this study was to evaluate current trends for postoperative MACE after bariatric surgery in both accredited and nonaccredited centers and the factors affecting these trends.

SETTING

This retrospective study was conducted using National Inpatient Sample database from 2012 to 2019.

METHODS

All patients who underwent inpatient laparoscopic sleeve gastrectomy (LSG), open sleeve gastrectomy (SG), laparoscopic Roux-en-Y gastric bypass (LRYGB), and open Roux-en-Y gastric bypass (RYGB) were examined. Composite MACE (acute myocardial infarction, cardiac arrest, acute stroke, and in-hospital death during bariatric surgery hospitalization) was calculated and analyzed over time along with patient demographic and co-morbid diseases using survey-weighted logistic regression.

RESULTS

MACE incidence was lowest for LSG (0.07%), followed by LRYGB (0.16%), SG (3.47%), and RYBG (3.51%). Open procedure, increasing age, male sex, body mass index ≥50, coronary artery disease, congestive heart failure, and chronic kidney disease were independent predictors for increased MACE risk. MACE incidence increased over time for SG (odds ratio [OR] 1.25 [1.16, 1.34]; P < .0001) and RYGB (OR 1.14 [1.06, 1.22]; P = .0004) but decreased for LRYGB (OR 0.93 [0.87, 1] P = .06). After adjustment for high-risk covariates, increased MACE trend seen over time was attenuated in SG (OR 1.13 [1.04-1.22]; P = .005) and RYGB (OR 1.04 [0.96-1.12]; P = .36), while there was minimal effect of these high-risk covariates on MACE trend over time in LSG and LRYGB.

CONCLUSIONS

MACE following LSG and LRYGB is rare, occurring in 0.1% of patients. Persistently increasing high-risk conditions and demographics has had minimal effect on MACE over time for LSG and LRYGB but has had significant effect on MACE trend over time in SG and RYGB.

Evaluation of CPAP adherence in bariatric patients diagnosed with obstructive sleep apnea: outcomes of a multicenter cohort study

Purpose

Obstructive sleep apnea (OSA) is highly prevalent but mostly undiagnosed in obese patients scheduled for bariatric surgery. To prevent cardiopulmonary complications, many clinics perform preoperative OSA screening. Consequently, adequate adherence to continuous positive airway pressure (CPAP) therapy is essential but challenging. We aimed to evaluate CPAP adherence and its influence on postoperative outcomes.

Methods

In a prospective multicenter cohort study, we compared different perioperative strategies for handling undiagnosed OSA in bariatric patients. In this subgroup analysis, patients newly diagnosed with OSA were compared to those with pre-existing OSA. We assessed inadequate CPAP adherence, defined as < 4 h/night, between the preoperative period and 6 months postoperative. Cardiopulmonary complications and (un)scheduled ICU admissions were also evaluated.

Results

In total, 272 patients with newly diagnosed OSA (67.4%) and 132 patients with pre-existing OSA (32.6%) were included. Before surgery, 41 newly diagnosed patients used CPAP inadequately, compared to 5 patients with pre-existing OSA (15% vs. 4%, p = 0.049). Six months after surgery, inadequate CPAP use increased to 73% for newly diagnosed patients and 39% for patients with pre-existing OSA, respectively (p < 0.001). Incidences of cardiopulmonary complications, scheduled, and unscheduled ICU admissions were similar in the two study groups (p = 0.600, p = 0.972, and p = 0.980, respectively).

Conclusion

Inadequate CPAP adherence is higher in bariatric patients newly diagnosed with OSA when compared to patients with pre-existing OSA. Strategies to increase CPAP adherence may be valuable when considering routine OSA screening and CPAP therapy in patients undergoing bariatric surgery. Further studies are needed to improve current guidelines on perioperative OSA management of obese patients.

Trial registration

POPCORN study, registered at Netherlands Trial Register, https://www.trialregister.nl/trial/6805. ID no: 6805.

Polysomnography in pre-operative screening for obstructive sleep apnea in patients undergoing bariatric surgery: a retrospective cohort study

BACKGROUND/OBJECTIVES

To assess the impact of obstructive sleep apnea (OSA) screening with polysomnography on preventing cardiovascular and pulmonary complications in the postoperative period of bariatric surgery.

SUBJECTS/METHODS

This was a single-center retrospective cohort study, including 522 adults who underwent bariatric surgery between August 2010 and May 2019. Electronic medical records were accessed to obtain variables of interest. Screening for OSA was performed as a medical indication and registered as positive if apnea-hypopnea index was ≥5 events/hour in patients who did not have previous OSA diagnosis. The primary outcome was the presence of cardiac or pulmonary events in the 30-day postoperative period. Secondary outcomes included length of stay (days), need for an intensive care unit (ICU) after surgery, length of mechanical ventilation, and time from mechanical ventilation withdrawal. Statistical analyses were performed with χ², Fisher's exact test, Student's t-test, Mann-Whitney U test, and Poisson regression.

RESULTS

Most participants (n = 326) did not have OSA screening with polysomnography, while 196 had performed this screening. There was no difference in cardiopulmonary events between the screening and non-screening groups (4.2% vs. 2.8%; P = 0.45). Polysomnography screening could not reduce cardiovascular or pulmonary complications in the postoperative period, RR = 1.73 (95% CI: 0.68-4.14). There was no difference in ICU admission, length of stay, and time from mechanical ventilation between groups in secondary outcomes.

CONCLUSIONS

Our study suggests that OSA screening with polysomnography in the pre-operative care of bariatric surgery is a dispensable procedure, as it does not change postoperative cardiopulmonary outcomes. Indications for polysomnography should be made at the individual level.

30-day Major Adverse Cardiac Events (MACE) after elective bariatric surgery: the development and validation of the Bari-MACE clinical predictive tool

BACKGROUND

Major adverse cardiac events (MACEs) after bariatric surgery are poorly understood yet are thought to be associated with significant morbidity and mortality.

OBJECTIVES

To evaluate the prevalence and clinical impact of short-term, 30-day MACE and to develop a pragmatic clinical predictive MACE scoring tool.

SETTING

This retrospective study was conducted using all the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP)-accredited center data from 2015 to 2019.

METHODS

Primary Roux-en-Y and sleeve gastrectomy procedures were included, and prior revisional surgeries and emergency surgeries were excluded. Multivariable logistic regression modeling was used to examine the risk factors associated with 30-day MACE. Using forward regression, a Bari-MACE clinical prediction model was generated.

RESULTS

A total of 750,498 patients were included in our analysis of which 959 (.1%) experienced a MACE. MACE patients were older (54.0 ± 11.5 yr versus 44.4 ± 12.0 yr, P < .0001), and comprised a higher proportion of males (36.3% versus 20.4%, P < .0001) and patients of White racial status (74.0% versus 71.6%, P < .0001). The MACE cohort also had a higher body mass index (46.6 ± 9.7 kg/m² versus 45.2 ± 7.8 kg/m², P < .0001), higher rates of sleep apnea (56.8% versus 38.2%, P < .0001), and a higher proportion of insulin-dependent diabetes (26.1% versus 8.4%, P < .0001) than non-MACE patients. Derivation of our clinical predictive Bari-MACE scoring model revealed 12 variables associated with development of MACE with a specificity of 97.8% using a 55-point threshold.

CONCLUSION

Thirty-day major adverse cardiac events after elective bariatric surgery are rare, occurring in approximately .1% of all patients, but are associated with significant morbidity and mortality. Using the MBSAQIP, we developed a Bari-MACE clinical predictive tool to risk-stratify patients with the aim to better guide perioperative care and foster improved surgical outcomes.

Surgical, metabolic, and prognostic outcomes for Roux-en-Y gastric bypass versus sleeve gastrectomy: a systematic review

The purpose of this systematic review was to study 4 different aspects of Roux-en-Y gastric bypass (RYBG) and sleeve gastrectomy (SG). Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) are two commonly performed bariatric procedures. This systematic review aims to compare RYGB with SG when it comes to weight changes, and cardiometabolic risk profile. Another aim was to evaluate laparoscopic and robotic techniques for both surgeries. PubMED, Cochrane Library, and JAMA Network were searched for articles evaluating RYGB and SG from 2005-2020. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed. Four different categories were analyzed comparing RYGB with SG as well as robotic versus laparoscopic approach. The Critical Appraisal Skills Program (CASP) checklist was used to assess the quality of evidence in the studies included in this systematic review. A total of 29 studies were included looking at different aspects of RYGB and SG. RYGB is superior to SG for weight loss, improved or complete remission of cholesterol and hypertensive medications. Consensus is lacking regarding decrease in BMI, total cholesterol, and triglycerides. There is lack of evidence regarding decrease of incidence of MI or stroke. For RYGB and SG, the majority of studies found that the robotic technique was more expensive and took longer. RYGB when compared with SG was associated with larger weight loss, decreased or cessation of cholesterol and hypertensive medications, and lower cholesterol. Decrease in BMI had varying results, with RYGB being superior in more studies, while there was no difference in other studies. There was a lack of evidence to support if RYGB or SG was superior to decreasing triglyceride levels. For both RYGB and SG, the robotic approach was costlier and took more operating time versus the laparoscopic approach.

Trends in early postoperative major adverse cardiovascular and cerebrovascular events associated with bariatric surgery: an analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program data registry

BACKGROUND

The population undergoing bariatric surgery (BaS) has many cardiovascular risk factors that can lead to significant perioperative cardiovascular morbidity.

OBJECTIVES

We aimed to examine trends in the incidence of major adverse cardiovascular and cerebrovascular events (MACCE) after BaS.

SETTING

Academic Hospital, United States METHODS: We performed a retrospective analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) data registry for patients aged ≥18 years undergoing laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB) from 2015 to 2019. Data on demographics, co-morbidities, and type of procedure were collected. MACCE was defined as a composite variable including perioperative acute myocardial infarction (AMI), cardiac arrest requiring cardiopulmonary resuscitation, acute stroke, and all-cause mortality. We utilized the Cochrane-Armitage and Jonckheere-Terpstra tests to assess for significant trend changes throughout the years.

RESULTS

A total of 752,722 patients were included in our analysis (LSG = 73.2%, LRYGB = 26.8%). Postoperative MACCE occurred in 1058 patients (.14%), and was more frequent in patients undergoing LRYGB (.20%). The frequency of MACCE declined from .17% to .14% (P = .053), driven by a decline in the frequency of AMI (.04% to .02%, P = .002), cardiac arrest (.05% to .04%, P = .897), and all-cause death (.11% to .08%, P = .040), but with an increase in perioperative stroke (.01% to .02%, P = .057).

CONCLUSION

The overall risk of MACCE after BaS is .14% and has been declining in the last 5 years. This trend is likely multifactorial and further analysis is necessary to provide a detailed explanation.

The long-term risk of cardiovascular events in patients following bariatric surgery compared to a non-surgical population with obesity and the general population: a comprehensive national cohort study

PURPOSE

This study evaluated the differences in long-term cardiovascular events between obese patients who received bariatric surgery (BS), those who did not, and the general population (GP).

METHODS

Between 2003 and 2008, patients with severe obesity, aged 18-55 years, were divided into the non-surgical (NS) and BS groups and were included in this retrospective study. We also extracted data of healthy civilians defined as the GP. The incidence of cardiovascular events, including myocardial infarction, intracranial hemorrhage, epidural hemorrhage, ischemic stroke, and transient ischemic attack, was defined as the primary end point. Patients were followed up either until the end of 2013, upon reaching the primary end point, or death.

RESULTS

After propensity score matching, 1436 patients were included in both the BS and NS groups, and 4829 subjects were enrolled as the GP. Of these, 57 (3.9%), 10 (0.6%), and 30 (0.62%) subjects in the NS, BS, and GP, respectively, experienced cardiovascular events. Multivariate analysis revealed that patients with BS had a significantly lower risk of cardiovascular events (HR = 0.168; 95% CI 0.085-0.328; p < 0.001) than those in the NS group, but it was not significantly different in the BS group compared with the GP (HR = 1.202; 95% CI 0.585-2.471; p = 0.617).

CONCLUSION

Long-term risk of cardiovascular events was significantly lower among patients who had BS, compared to the NS obese patients. Thus, the long-term cardiovascular risk between those who received BS and the GP had no significant difference, in a retrospective view.

Preoperative cardiac screening using NT-proBNP in obese patients 50 years and older undergoing bariatric surgery: a study of 310 consecutive patients

Background

Obesity is associated with cardiovascular (CV) risk factors and diseases. Because bariatric surgery is increasingly performed in relatively elderly patients, a risk for pre- and postoperative CV complications exists.

Objectives

We aimed to assess the value of plasma N-terminal-probrain natriuretic peptide (NT-proBNP) as a CV screening tool.

Setting

High-volume bariatric center.

Methods

Between June 2019 and January 2020, all consecutive bariatric patients 50 years and older underwent preoperative NT-proBNP assessment in this cohort study to screen for CV disease. Patients with elevated NT-proBNP (≥125 pg/mL) were referred for further cardiac evaluation, including electrocardiography and echocardiography.

Results

We included 310 consecutive patients (median age, 56 years; 79% female; body mass index = 43±6.5 kg/m²). A history of CV disease was present in 21% of patients, mainly atrial fibrillation (7%) and coronary artery disease (10%). A total of 72 patients (23%) had elevated NT-proBNP levels, and 67 of them underwent further cardiac workup. Of these 67 patients, electrocardiography (ECG) showed atrial fibrillation in 7 patients (10%). On echocardiography, 3 patients had left ventricular ejection fraction (LVEF) <40%, 9 patients had LVEF 40%–49%, and 13 patients had LVEF ≥50% with structural and/or functional remodeling. In 2 patients, elevated NT-proBNP prompted workup leading to a diagnosis of coronary artery disease and consequent percutaneous coronary intervention in 1 patient.

Conclusions

Elevated NT-proBNP levels are present in 23% of patients 50 years and older undergoing bariatric surgery. In 37% of them, there was echocardiographic evidence for structural and/or functional remodeling. Further studies are needed to assess if these preliminary results warrant routine application of NT-proBNP to identify patients at risk for CV complications after bariatric surgery.

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This study assessed NT-proBNP as a cardiac screening tool in bariatric patients.

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Elevated NT-proBNP levels were present in 23% of patients ≥50 years.

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In 37% of them (n=25), echocardiography showed LV dysfunction or heart failure.

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NT-proBNP is a non-invasive tool that can detect new CV diseases in bariatric patients