Rescue bariatric surgery for obesity-induced cardiomyopathy

A Population-Based Study of Early Postoperative Outcomes in Patients with Heart Failure Undergoing Bariatric Surgery

BACKGROUND

Weight loss following bariatric surgery can improve cardiac function among patients with heart failure (HF). However, perioperative morbidity of bariatric surgery has not been evaluated in patients with HF.

STUDY DESIGN

The National Surgical Quality Improvement Project (NSQIP) database for 2006-2014 was queried to identify patients undergoing adjustable gastric band, gastric bypass, sleeve gastrectomy, and biliopancreatic diversion-duodenal switch. Patients with HF were propensity matched to a control group without HF (1:5). Univariate analyses evaluated differences in complications, and multivariate analysis was completed to predict all-cause morbidity.

RESULTS

There were 237 patients identified with HF (mean age 52.8 years, 59.9% female, mean body mass index 50.6 kg/m²) matched to 1185 controls without HF who underwent bariatric surgery. Preoperatively, patients with HF were more likely to be taking antihypertensive medication and have undergone prior percutaneous cardiac intervention and cardiac surgery. There was no difference in operative time, surgical site infections, acute renal failure, re-intubation, or myocardial infarction. HF was associated with increased likelihood of length of stay more than 7 days, likelihood to remain ventilated > 48 h, venous thromboembolism, and reoperation. For patients with HF, the adjusted odds ratio for all-cause morbidity was 2.09 (1.32-3.22).

CONCLUSION

The NSQIP definition of HF, which includes recent hospitalization for HF exacerbation or new HF diagnosis 30 days prior to surgery, predicts a more than two-fold increase in odds of morbidity following bariatric surgery. This must be balanced with the longer-term potential benefits of weight loss and associated improvement in cardiac function in this population.

Clinical and Echocardiographic Outcomes After Bariatric Surgery in Obese Patients With Left Ventricular Systolic Dysfunction

BACKGROUND

Obesity is a risk factor for development of left ventricular systolic dysfunction (LVSD) and can complicate LVSD management, especially for individuals in whom cardiac transplantation is indicated. Bariatric surgery is increasingly recognized as a safe and effective intervention to achieve marked weight loss, but experience is limited in the LVSD population.

METHODS AND RESULTS

We retrospectively reviewed patients with obesity and left ventricular ejection fraction (LVEF) <50% who underwent bariatric surgery at a tertiary center 2004 to 2013. An analysis of outcomes and efficacy compared 42 surgical patients with LVSD to 2588 without known LVSD. The LVSD group had greater baseline prevalence of comorbidities and showed a slight excess of early postoperative heart failure and myocardial infarction. However, patients with LVSD achieved good weight loss efficacy (mean decrease 22.6%) and no excess in mortality at 1 year. An overlapping cohort of 38 patients with LVSD had both pre- and postoperative echocardiographic images available for review by 2 blinded readers. Obese nonsurgical controls were matched on age, sex, initial LVEF, and interval between echocardiograms. There was a mean pre- to postoperative LVEF improvement of +5.1% ±8.3 (P=0.0005) for surgical subjects, but not for controls (+3.4%±10.5, P=0.056). Among surgical subjects, 11 patients had an LVEF improvement of >10%, whereas only 6 improved by >10% among nonsurgical controls.

CONCLUSIONS

At experienced centers, bariatric surgery may be a safe and effective intervention for obese patients with LVSD. Bariatric surgery was associated with an improvement in LVEF, although the magnitude of change was on the cusp of clinical significance.

Should we target obesity in advanced heart failure?

OPINION STATEMENT

Obesity is a risk factor for the development of heart failure (HF), but has been associated with improved survival in patients with established HF. Weight loss should clearly be recommended and supported for obese individuals without cardiac pathology to prevent cardiomyopathy development. Clinical recommendations at the other end of the obesity heart failure spectrum are also relatively clear. Morbidly obese individuals (BMI ≥ 40 kg/m(2)) aged <50 years with severely depressed systolic function and NYHA class III-IV symptoms should be considered for malabsorptive bariatric surgery at an experienced center. The goal is either improved systolic function and symptoms, or sufficient weight loss for heart transplant eligibility. Recommendations for patients falling between these extremes are more challenging. Overweight and mildly obese HF patients (25-35 kg/m(2)) may be somewhat protected from cardiac cachexia and weight loss is not expected to enhance survival, but may offer symptomatic benefits.

Bariatric surgery to unload the stressed heart: a metabolic hypothesis

Obesity is an independent risk factor for cardiovascular disease. Data from the Framingham Study have reported a higher incidence of heart failure in obese individuals compared with a normal cohort. The body initially copes with the abundance of fuel present in an obese milieu by storing it in adipose tissue. However, when the storage capacity is exceeded, the excess energy is taken up and stored ectopically as fat in vital organs such as the heart. Indeed, intramyocardial lipid overload is present in hearts of obese patients, as well as in hearts of animal models of obesity, and is associated with a distinct gene expression profile and cardiac dysfunction. By imposing a metabolic stress on the heart, obesity causes it to hypertrophy and ultimately to fail. Conventional measures to treat obesity include diet, exercise, and drugs. More recently, weight loss surgery (WLS) has achieved increasing prominence because of its ability to reduce the neurohumoral load, normalize metabolic dysregulation, and improve overall survival. The effects of WLS on systemic metabolic, neurohumoral, and hemodynamic parameters are well described and include an early normalization of serum glucose and insulin levels as well as reduction in blood pressure. WLS is also associated with reverse cardiac remodeling, regression of left ventricular hypertrophy, and improved left ventricular and right ventricular function. By targeting the source of the excess energy, we hypothesize that WLS improves contractile function by limiting exogenous substrate availability to the metabolically overloaded heart. These changes have also been found to be associated with increased levels of adiponectin and improved insulin sensitivity. Taken together, the sustained beneficial effects of WLS on left ventricular mass and function highlight the need to better understand the mechanism by which obesity regulates cardiovascular physiology.

Progressive regression of left ventricular hypertrophy two years after bariatric surgery

BACKGROUND

Obesity is a systemic disorder associated with an increase in left ventricular mass and premature death and disability from cardiovascular disease. Although bariatric surgery reverses many of the hormonal and hemodynamic derangements, the long-term collective effects on body composition and left ventricular mass have not been considered before. We hypothesized that the decrease in fat mass and lean mass after weight loss surgery is associated with a decrease in left ventricular mass.

METHODS

Fifteen severely obese women (mean body mass index [BMI]: 46.7+/-1.7 kg/m(2)) with medically controlled hypertension underwent bariatric surgery. Left ventricular mass and plasma markers of systemic metabolism, together with body mass index (BMI), waist and hip circumferences, body composition (fat mass and lean mass), and resting energy expenditure were measured at 0, 3, 9, 12, and 24 months.

RESULTS

Left ventricular mass continued to decrease linearly over the entire period of observation, while rates of weight loss, loss of lean mass, loss of fat mass, and resting energy expenditure all plateaued at 9 [corrected] months (P <.001 for all). Parameters of systemic metabolism normalized by 9 months, and showed no further change at 24 months after surgery.

CONCLUSIONS

Even though parameters of obesity, including BMI and body composition, plateau, the benefits of bariatric surgery on systemic metabolism and left ventricular mass are sustained. We propose that the progressive decrease of left ventricular mass after weight loss surgery is regulated by neurohumoral factors, and may contribute to improved long-term survival.

American Association of Clinical Endocrinologists, The Obesity Society, and American Society for Metabolic & Bariatric Surgery medical guidelines for clinical practice for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient

American Association of Clinical Endocrinologists, The Obesity Society, and American Society for Metabolic & Bariatric Surgery Medical Guidelines for Clinical Practice are systematically developed statements to assist health-care professionals in medical decision making for specific clinical conditions. Most of the content herein is based on literature reviews. In areas of uncertainty, professional judgment was applied. These guidelines are a working document that reflects the state of the field at the time of publication. Because rapid changes in this area are expected, periodic revisions are inevitable. We encourage medical professionals to use this information in conjunction with their best clinical judgment. The presented recommendations may not be appropriate in all situations. Any decision by practitioners to apply these guidelines must be made in light of local resources and individual patient circumstances. The American Society for Parenteral & Enteral Nutrition fully endorses sections of these guidelines that address the metabolic and nutritional management of the bariatric surgical patient.

American Association of Clinical Endocrinologists, The Obesity Society, and American Society for Metabolic & Bariatric Surgery Medical Guidelines for Clinical Practice for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient

American Association of Clinical Endocrinologists, The Obesity Society, and American Society for Metabolic & Bariatric Surgery Medical Guidelines for Clinical Practice are systematically developed statements to assist healthcare professionals in medical decision making for specific clinical conditions. Most of the content herein is based on literature reviews. In areas of uncertainty, professional judgment was applied. These guidelines are a working document that reflects the state of the field at the time of publication. Because rapid changes in this area are expected, periodic revisions are inevitable. We encourage medical professionals to use this information in conjunction with their best clinical judgment. The presented recommendations may not be appropriate in all situations. Any decision by practitioners to apply these guidelines must be made in light of local resources and individual patient circumstances. The American Society for Parenteral & Enteral Nutrition fully endorses sections of these guidelines that address the metabolic and nutritional management of the bariatric surgical patient.