Bariatric Surgery as a Bridge to Heart Transplantation in Morbidly Obese Patients: a Systematic Review and Meta-Analysis

Obesity, organ failure, and transplantation: a review of the role of metabolic and bariatric surgery in transplant candidates and recipients

Obesity is a risk factor for kidney, liver, heart, and pulmonary diseases, as well as failure. Solid organ transplantation remains the definitive treatment for the end-stage presentation of these diseases. Among many criteria for organ transplant, efficient management of obesity is required for patients to acquire transplant eligibility. End-stage organ failure and obesity are 2 complex pathologies that are often entwined. Metabolic and bariatric surgery before, during, or after organ transplant has been studied to determine the long-term effect of bariatric surgery on transplant outcomes. In this review, a multidisciplinary group of surgeons from the Society of American Gastrointestinal and Endoscopic Surgeons and the American Society for Transplant Surgery presents the current published literature on metabolic and bariatric surgery as a therapeutic option for patients with obesity awaiting solid organ transplantation. This manuscript details the most recent recommendations, pharmacologic considerations, and psychological considerations for this specific cohort of patients. Since level one evidence is not available on many of the topics covered by this review, expert opinion was implemented in several instances. Additional high-quality research in this area will allow for better recommendations and, therefore, treatment strategies for these complex patients.

Laparoscopic Sleeve Gastrectomy as a First Step Procedure for Oncologic Purposes: An Indication Beyond the Updated Guidelines

BACKGROUND

Obesity is a well-established risk factor for cancer. Laparoscopic sleeve gastrectomy (LSG) is established as a safe procedure providing accelerated weight loss and comorbidity improvement or remission. Additionally, it is approved as a bridging procedure for various non-oncologic surgeries, with very limited data for oncologic procedures. The aim of this study is to present a series of patients with severe obesity and concomitant cancer who underwent LSG prior to definitive oncological procedure.

METHODS

A retrospective review (2008-2023) was conducted in three institutions, identifying 5 patients with cancer and severe obesity who underwent LSG as bridging procedure. Variables analyzed were initial weight, initial body mass index (BMI), type of malignancy, comorbidities, interval between LSG and oncological surgery, weight and BMI before the second intervention, percentage of excess weight loss (%EWL), and postoperative morbidity and mortality.

RESULTS

Malignancies identified were 2 prostate cancers, 1 periampullary neuroendocrine tumor, 1 rectal cancer, and 1 renal clear cell carcinoma. Mean age of patients was 50.2 years, mean initial BMI 47.4 kg/m 2 , and mean BMI before oncological surgery 37 kg/m 2 . Mean time interval between LSG and oncological surgery was 8.3 months. Mean %EWL achieved was 45.2%. Two thromboembolic events were encountered after LSG, while none of the patients developed complications after definitive oncological treatment. The mean follow-up after oncological surgery was 61.6 months.

CONCLUSION

LSG can be proposed as bridging procedure before oncological surgery in meticulously selected patients. Achieved weight loss can render subsequent oncological procedures easier and safer.

Bariatric surgery is as safe as other common operations: an analysis of the ACS-NSQIP

BACKGROUND

Metabolic and Bariatric Surgery (MBS) is the most effective management for patients with obesity and weight-related medical conditions. Nonetheless, some primary care physicians (PCPs) and surgeons from other specialties are reluctant to refer patients for MBS due to safety concerns.

OBJECTIVES

To compare the outcomes of patients who underwent MBS with those who underwent other common operations.

SETTING

American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP).

METHODS

Patients who underwent laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass (RYGB), classified as MBS, were compared to nine frequently performed procedures including hip arthroplasty and laparoscopic cholecystectomy, appendectomy, colectomy, hysterectomy, and hernia repairs, among others. A multivariable logistic regression was constructed to compare outcomes including readmission, reoperation, extended length of stay (ELOS) (>75th percentile or ≥3 days) and mortality.

RESULTS

A total of 1.6 million patients were included, with 11.1% undergoing MBS. The odds of readmission were marginally lower in the cholecystectomy (adjusted odds ratio [aOR] = .88, 95% confidence interval (CI) [.85, .90]) and appendectomy (aOR = .88, 95% CI [.85, .90]) cohorts. Similarly, odds of ELOS were among the lowest, surpassed only by same-day procedures such as cholecystectomies and appendectomies. The MBS group had significantly low odds of mortality, comparable to safe anatomical procedures such as hernia repairs. Infectious and thrombotic complications were exceedingly rare and amongst the lowest after MBS.

CONCLUSIONS

MBS demonstrates a remarkably promising safety profile and compares favorably to other common procedures in the short-term. PCPs and surgeons from other specialties can confidently refer patients for these low-risk, lifesaving operations.

Obesity, organ failure, and transplantation: A review of the role of metabolic and bariatric surgery in transplant candidates and recipients

Obesity is a risk factor for kidney, liver, heart, and pulmonary diseases, as well as failure. Solid organ transplantation remains the definitive treatment for the end-stage presentation of these diseases. Among many criteria for organ transplant, efficient management of obesity is required for patients to acquire transplant eligibility. End-stage organ failure and obesity are 2 complex pathologies that are often entwined. Metabolic and bariatric surgery before, during, or after organ transplant has been studied to determine the long-term effect of bariatric surgery on transplant outcomes. In this review, a multidisciplinary group of surgeons from the Society of American Gastrointestinal and Endoscopic Surgeons and the American Society for Transplant Surgery presents the current published literature on metabolic and bariatric surgery as a therapeutic option for patients with obesity awaiting solid organ transplantation. This manuscript details the most recent recommendations, pharmacologic considerations, and psychological considerations for this specific cohort of patients. Since level one evidence is not available on many of the topics covered by this review, expert opinion was implemented in several instances. Additional high-quality research in this area will allow for better recommendations and, therefore, treatment strategies for these complex patients.

Special Considerations for Advanced Heart Failure Surgeries: Durable Left Ventricular Devices and Heart Transplantation

Heart transplantation and durable left ventricular assist devices (LVADs) represent two definitive therapies for end-stage heart failure in the modern era. Despite technological advances, both treatment modalities continue to experience unique risks that impact surgical and perioperative decision-making. Here, we review special populations and factors that impact risk in LVAD and heart transplant surgery and examine critical decisions in the management of these patients. As both heart transplantation and the use of durable LVADs as destination therapy continue to increase, these considerations will be of increasing relevance in managing advanced heart failure and improving outcomes.

The impact of obesity and LVAD-bridging on heart transplant candidate outcomes: a linked STS INTERMACS - OPTN/UNOS data analysis

BACKGROUND

Limited data integrating waitlist and postheart transplant (HT) mortality have evaluated outcomes of left ventricular assist device (LVAD)-bridged strategy vs no LVAD according to patient characteristics. We evaluated waitlist and post-HT mortality in LVAD-bridged vs nonbridged patients based on body mass index (BMI).

METHODS

We included linked adults listed for HT in Organ Procurement and Transplant Network/United Network for Organ Sharing and patients receiving durable LVAD as bridge to HT or candidacy in Society of Thoracic Surgeons/Interagency Mechanical Circulatory Support databases (2010-2019). Using BMI at listing or LVAD implant, we categorized patients as underweight (<18.5 kg/m2), normal weight (18.5-24.99 kg/m2), overweight (25-29.99 kg/m2), and obese (≥30 kg/m2). Kaplan-Meier analysis and multivariable Cox proportional hazards models informed the effect of LVAD-bridged and nonbridged strategy by BMI on waitlist, post-HT, and overall mortality (including waitlist and post-HT mortality).

RESULTS

Among 11,216 LVAD-bridged and 17,122 nonbridged candidates, bridged candidates were more frequently obese (37.3% vs 28.6%) (p < 0.001). Multivariable analysis indicated increased waitlist mortality in LVAD-bridged vs nonbridged with overweight (Hazard ratio (HR) 1.18, 95% confidence interval (CI) 1.02-1.36) or obesity (HR 1.35, 95%CI 1.17-1.56) in comparison to normal weight candidates (HR 1.02, 95%CI 0.88-1.19) (p-interaction < 0.001). Post-transplant mortality was not statistically different in LVAD-bridged vs nonbridged patients across BMI categories (p-interaction = 0.26). There was a nonsignificant graded increase in overall mortality in LVAD-bridged with overweight (HR 1.53, 95%CI 1.39-1.68) or obesity (HR 1.61, 95%CI 1.46-1.78) compared to nonbridged patients (p-interaction = 0.13).

CONCLUSIONS

LVAD-bridged candidates with obesity had higher waitlist mortality compared to nonbridged candidates with obesity. Post-transplant mortality was similar in LVAD-bridged and nonbridged patients, but obesity remained associated with increased mortality in both groups. This study may aid clinicians and advanced heart failure patients with obesity in decision-making.

Bariatric surgery and left ventricular assist device in patients with heart failure: A systematic review and meta-analysis

BACKGROUND

The role of metabolic and bariatric surgery (MBS), in synergy with left ventricular assist device (LVAD) implantation, in the scope of end-stage heart failure management for patients with severe obesity is not well elucidated.

METHODS

We conducted a meta-analysis using Cochrane, Embase, PubMed, and Scopus databases to include articles from their inception to November 2022.

RESULTS

A total of 271 patients who underwent MBS during or after the LVAD implantation were included from eleven separate studies. After surgery, 67.4% of patients were listed on the heart transplant waitlist with 32.5% undergoing a successful transplant. We reported a mean listing time of 13.8 months. Finally, the pooled postoperative complication rate, 30-day readmission rate, and one-year mortality rate were 47.6%, 23.6% and 10.2% respectively.

CONCLUSIONS

MBS and LVAD is a safe and effective approach to bridge patients with severe obesity and end-stage heart failure for definitive heart transplantation.

Association of Size Matching Using Predicted Heart Mass With Mortality in Heart Transplant Recipients With Obesity or High Pulmonary Vascular Resistance

Importance

Pretransplant obesity and higher pulmonary vascular resistance (PVR) are risk factors for death after heart transplant. However, it remains unclear whether appropriate donor-to-recipient size matching using predicted heart mass (PHM) is associated with lower risk.

Objective

To investigate the association of size matching using PHM with risk of death posttransplant among patients with obesity and/or higher PVR.

Design, Setting, and Participants

All adult patients (>18 years) who underwent heart transplant between 2003 and 2022 with available information using the United Network for Organ Sharing cohort database. Multivariable Cox models and multivariable-adjusted spline curves were used to examine the risk of death posttransplant with PHM matching. Data were analyzed from October 2022 to March 2023.

Exposure

Recipient's body mass index (BMI) in categories (<18.0 [underweight], 18.1-24.9 [normal weight, reference], 25.0-29.9 [overweight], 30.0-34.9 [obese 1], 35-39.9 [obese 2], and ≥40.0 [obese 3]) and recipient's pretransplant PVR in categories of less than 4 (29 061 participants), 4 to 6 (2842 participants), and more than 6 Wood units (968 participants); and less than 3 (24 950 participants), 3 to 5 (6115 participants), and 5 or more (1806 participants) Wood units.

Main Outcome

All-cause death posttransplant on follow-up.

Results

The mean (SD) age of the cohort of 37 712 was 52.8 (12.8) years, 27 976 (74%) were male, 25 342 were non-Hispanic White (68.0%), 7664 were Black (20.4%), and 3139 were Hispanic or Latino (8.5%). A total of 12 413 recipients (32.9%) had a normal BMI, 13 849 (36.7%) had overweight, and 10 814 (28.7%) had obesity. On follow-up (median [IQR] 5.05 [0-19.4] years), 12 785 recipients (3046 female) died. For patients with normal weight, overweight, or obese 2, receiving a PHM-undermatched heart was associated with an increased risk of death (normal weight hazard ratio [HR], 1.20; 95% CI, 1.07-1.34; overweight HR, 1.12; 95% CI, 1.02-1.23; and obese 2 HR, 1.07; 95% CI, 1.01-1.14). Moreover, patients with higher pretransplant PVR who received an undermatched heart had a higher risk of death posttransplant in multivariable-adjusted spline curves in graded fashion until appropriately matched. In contrast, risk of death among patients receiving a PHM-overmatched heart did not differ from the appropriately matched group, including in recipients with an elevated pretransplant PVR.

Conclusion and Relevance

In this cohort study, undermatching donor-to-recipient size according to PHM was associated with higher posttransplant mortality, specifically in patients with normal weight, overweight, or class II obesity and in patients with elevated pretransplant PVR. Overmatching donor-to-recipient size was not associated with posttransplant survival.

2022 American Society of Metabolic and Bariatric Surgery (ASMBS) and International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) Indications for Metabolic and Bariatric Surgery

MAJOR UPDATES TO 1991 NATIONAL INSTITUTES OF HEALTH GUIDELINES FOR BARIATRIC SURGERY: Metabolic and bariatric surgery (MBS) is recommended for individuals with a body mass index (BMI) >35 kg/m2, regardless of presence, absence, or severity of co-morbidities.MBS should be considered for individuals with metabolic disease and BMI of 30-34.9 kg/m2.BMI thresholds should be adjusted in the Asian population such that a BMI >25 kg/m2 suggests clinical obesity, and individuals with BMI >27.5 kg/m2 should be offered MBS.Long-term results of MBS consistently demonstrate safety and efficacy.Appropriately selected children and adolescents should be considered for MBS.(Surg Obes Relat Dis 2022; https://doi.org/10.1016/j.soard.2022.08.013 ) © 2022 American Society for Metabolic and Bariatric Surgery. All rights reserved.

2022 American Society for Metabolic and Bariatric Surgery (ASMBS) and International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO): Indications for Metabolic and Bariatric Surgery

Major updates to 1991 National Institutes of Health guidelines for bariatric surgery.

Isolated Left Ventricular Assist Device Implantation Produces Variable Changes to Patient Body Mass Index

BACKGROUND

Body Mass Index (BMI) is an important consideration for transplant-eligible Left Ventricular Assist Device (LVAD) recipients. LVAD therapy's impact on BMI is unclear. We evaluated BMI changes in patients who underwent LVAD implantation. The association between these patients' BMI and transplant was studied.

METHODS

This was a retrospective cohort study of patients who underwent LVAD implantation between January 1, 2012-December 31, 2018 at our institution. Patients were stratified by preoperative BMI (kg/m² ) into 4 groups: < 30, 30-34.9, 34.9-39.9, and ≥40. BMI data was collected at 12 and 6 months prior to implant, time of implantation, and 3- and 6- months post-implantation.

RESULTS

107 patients underwent LVAD implantation at our institution. Data was available for 80 patients. Baseline characteristics included mean age 56.0 years, 69% male, and mean implant BMI 29.9 ± 6.8 kg/m² . The mean BMI (kg/m² ) with each of the BMI (kg/m² ) groups <30, 30-34.9, 35-39.9, and ≥ 40 (n= 60, 25, 12, 10 respectively) was 25.1., 32.5, 36.8, and 43.8, respectively. There was no consistent pattern with weight change across differing implant BMIs. No patient with a BMI of <30 gained sufficient weight to impact transplant candidacy. 23% of patients with BMI of 30-34.9 kg/m² , 60% of patients with a BMI 35-39.9 kg/m² , and 87.5% of patients with a BMI of ≥40 had a 6-month BMI potentially affecting transplant.

CONCLUSIONS

Associated weight changes during LVAD support may significantly impact transplant candidacy. Higher BMI groups may benefit from multimodal and multidisciplinary targeted weight-loss interventions.

Sleeve gastrectomy to aortic valve replacement: safe?

BACKGROUND

Bariatric surgery has favorable results on cardiac structure and function, but there is minimal research on its utility in the cardiac comorbid population.

OBJECTIVES

To determine if laparoscopic sleeve gastrectomy (SG) is safe in patients with symptomatic aortic stenosis (AS).

SETTING

Community hospital/bariatric center of excellence in Pennsylvania.

METHODS

Retrospective single center review of 18 patients with morbid obesity and clinically significant AS. All SGs were performed between June 2016 and June 2020. Outcomes including hospital length of stay, 30-day readmission, and 30-day mortality in the study population (n = 18) were compared with 100 patients without AS who underwent SG at the same institution during the same time.

RESULTS

There were no perioperative deaths. Mean hospital stay in the study group was 1.78 days compared with 1.3 days in the noncardiac group (P = .1154). Two of 18 patients (11.1%) required readmission within 30 days, both for clinically significant bleeding, compared with 2 of 100 noncardiac patients (2.0%) (P = .1097). Seventeen of 18 study patients went on to have definitive aortic valve replacement surgery.

CONCLUSION

SG appears safe in patients with clinically significant AS. Although the AS group did have a higher rate of complications, these were manageable and did not increase mortality or LOS. Further studies are required to determine if outcomes of definitive aortic valve replacement are improved after bariatric surgery.