Are preoperative obesity and cachexia risk factors for post heart transplant morbidity and mortality: a multi-institutional study of preoperative weight-height indices. Cardiac Transplant Research Database (CTRD) Group

A second chance for a new heart? The role of metabolic and bariatric surgery in patients with end-stage heart failure

BACKGROUND

Obesity is an independent risk factor for heart failure (HF). Substantial weight loss has been shown to reverse obesity-related cardiomyopathy. This study aimed to report our institution's experience with laparoscopic sleeve gastrectomy (LSG) in patients with morbid obesity and end-stage HF.

METHODS

Between 2018 and 2022, 26 patients with end-stage HF were referred for LSG. Of 26 patients, 16 underwent an operation, and 10 did not. After institutional review board approval, a retrospective electronic medical record review was performed to evaluate (i) age, (ii) preoperative weight, (iii) decrease in body mass index (BMI) score, (iv) whether the patient underwent heart transplantation, and (v) mortality. Data analysis was performed using Stata/SE (version 17.0; StataCorp). The Wilcoxon rank-sum test was used to compare continuous variables between the cohorts, and the Pearson chi-square test was used for binary variables with Bonferroni correction applied.

RESULTS

The LSG and non-LSG cohorts had comparable ages (P = .088) and starting BMI score (P = .918), and a proportion of patients had a ventricular assist device (P = .191). Patients who underwent LSG lost significantly more weight than the patients who did not, with an average decrease in BMI score of 8.9 kg/m2 (SD, ±6.13) and 1.1 kg/m2 (SD, ±4.10), respectively (P = .040). Of note, 6 patients (37.5%) who underwent LSG eventually underwent transplantation, compared with 2 patients (20.0%) from the matched cohort (P = .884). Of the 26 patients, there were 6 deaths: 2 (12.5%) in the LSG cohort and 4 (40.0%) in the non-LSG cohort (P = .525).

CONCLUSION

LSG may be safe and effective for weight loss in patients with HF. This operation may provide patients affected by obesity with end-stage HF the lifesaving opportunity to achieve transplant candidacy.

Elevated serum albumin-to-creatinine ratio as a protective factor on outcomes after heart transplantation

Background

The purpose of this study was to investigate the prognostic significance of serum albumin to creatinine ratio (ACR) in patients receiving heart transplantation of end-stage heart failure.

Methods

From January 2015 to December 2020, a total of 460 patients who underwent heart transplantation were included in this retrospective analysis. According to the maximum Youden index, the optimal cut-off value was identified. Kaplan-Meier methods were used to describe survival rates, and multivariable analyses were conducted with Cox proportional hazard models. Meanwhile, logistic regression analysis was applied to evaluate predictors for postoperative complications. The accuracy of risk prediction was evaluated by using the concordance index (C-index) and calibration plots.

Results

The optimal cut-off value was 37.54 for ACR. Univariable analysis indicated that recipient age, IABP, RAAS, BB, Hb, urea nitrogen, D-dimer, troponin, TG, and ACR were significant prognostic factors of overall survival (OS). Multivariate analysis showed that preoperative ACR (HR: 0.504, 95% = 0.352-0.722, P < 0.001) was still an independent prognostic factor of OS. The nomogram for predicting 1-year and 5-year OS in patients who underwent heart transplantation without ACR (C-index = 0.631) and with ACR (C-index = 0.671). Besides, preoperative ACR level was a significant independent predictor of postoperative respiratory complications, renal complications, liver injury, infection and in-hospital death. Moreover, the calibration plot showed good consistency between the predictions by the nomogram for OS and the actual outcomes.

Conclusion

Our research showed that ACR is a favorable prognostic indicator in patients of heart transplantation.

Weight gain post-heart transplantation is associated with an increased risk for allograft vasculopathy and rejection

OBJECTIVE

Obesity and overweight are associated with an increased risk for cardiovascular disease. Since fat mass (FM) and fat-free mass (FFM) both contribute to total body weight (TBW), we characterized the post-heart transplantation (HT) change in TBW and its implications for outcomes.

METHODS

Post-HT changes in TBW, FM, and FFM were reviewed for 211 HT patients assessed during 1997-2017. Endpoints included cardiac allograft vasculopathy (CAV) and rejection.

RESULTS

Median TBW increased by 7.3% at 1 year, with a significant rise in the obese category (28% vs. 13%, p < 0.001) and with FM versus FFM making the main contribution (23% vs. 3%, p < 0.001). When patients were divided according to median TBW change ("high" vs. "low"), Kaplan-Meier analysis showed that 10-year freedom from CAV (log-rank p < 0.005) and rejection (log-rank p < 0.01) was significantly higher for the "low" TBW change group. Consistently, multivariable analyses showed that the "high" group was independently associated with significant 3.5-fold and 4.2-fold increased risks for CAV (95% CI 1.4-8.7, p = 0.01) and rejection (95% CI 1.2-15.4, p = 0.03), respectively.

CONCLUSIONS

Weight gain, contributed mostly by FM, is independently associated with an increased risk for CAV and rejection. Follow-up emphasis should be placed on weight gain and preventative measures.

A Systematic Review for Variables to Be Collected in a Transplant Database for Improving Risk Prediction

BACKGROUND

This systematic review was commissioned to identify new variables associated with transplant outcomes that are not currently collected by the Organ Procurement and Transplantation Network (OPTN).

METHODS

We identified 81 unique studies including 1 193 410 patients with median follow-up of 36 months posttransplant, reporting 108 unique risk factors.

RESULTS

Most risk factors (104) were recipient related; few (4) were donor related. Most risk factors were judged to be practical and feasible to routinely collect. Relative association measures were small to moderate for most risk factors (ranging between 1.0 and 2.0). The strongest relative association measure for a heart transplant outcome with a risk factor was 8.6 (recipient with the previous Fontan operation), for a kidney transplant 2.8 (sickle cell nephropathy as primary cause of end-stage renal disease), for a liver transplant 14.3 (recipient serum ferritin >500 µg/L), and for a lung transplant 6.3 (Burkholderia cepacia complex infection for 1 y or less). OPTN may consider some of these 108 variables for future collection to enhance transplant research and clinical care.

CONCLUSIONS

Evidence-based approaches can be used to determine variables collected in databases and registries. Several candidate variables have been identified for OPTN.

Impact of Obesity on Ventricular Assist Device Outcomes

BACKGROUND

Obesity remains a relative contraindication for heart transplantation, and hence, obese patients with advanced heart failure receive ventricular assist devices (VADs) either as a destination or "bridge to weight loss" strategy. However, impact of obesity on clinical outcomes after VAD implantation is largely unknown. We sought to determine the clinical outcomes of obese patients with body mass index (BMI) ≥ 35 kg/m²) following contemporary VAD implantation.

METHODS

The Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) registry was queried for patients who underwent VAD implantation. Patients were categorized into BMI groups based on World Health Organization classification.

RESULTS

Of 17,095 patients, 2620 (15%) had a BMI ≥ 35 kg/m². Obese patients were likely to be young, non-white, females with dilated cardiomyopathy and undergo device implantation as destination. Survival was similar amongst BMI groups (P = .058). Obese patients had significantly higher risk for infection (hazard ratio [HR]: 1.215; P = .001), device malfunction or thrombosis (HR: 1.323; P ≤ .001), cardiac arrhythmia (HR: 1.188; P = .001) and hospital readmissions (HR: 1.073; P = .022), but lower risk of bleeding (HR: 0.906; P = .018). Significant weight loss (≥10%) during VAD support was achieved only by a small proportion (18.6%) of patients with BMI ≥ 35 kg/m². Significant weight loss rates observed in obese patients with VAD implantation as destination and bridge to transplant strategy were comparable. Obese patients with significant weight loss were more likely to undergo cardiac transplantation. Weight loss worsened bleeding risk without altering risk for infection, cardiac arrhythmia, and device complications.

CONCLUSIONS

Obesity alone should not be considered a contraindication for VAD therapy in contemporary era. Given durability of heart transplantation, strategies should be developed to promote weight loss, which occurs infrequently in obese patients. Impact of weight loss on clinical outcome of obese patients warrants further investigation.

Impact of ventricular assist device implantation on the nutritional status of children awaiting heart transplantation

BACKGROUND

Malnutrition is common in pediatric heart failure and is associated with mortality. The effect of VAD support on malnutrition in children is unknown. We sought to compare the prevalence and severity of malnutrition at HT in children on VAD support vs OMT to inform decisions regarding support strategies.

METHODS

Retrospective chart review involving all patients <18 years who underwent HT at Stanford between 1/1/2011 and 3/1/2018. Malnutrition diagnosis and severity were defined by ASPEN guidelines using the lowest age-adjusted z-score for weight (WAZ), height (HAZ), and BMI (BMIZ) when the patient was euvolemic. Changes in z-scores from baseline to HT and across groups were analyzed.

RESULTS

A total of 104 patients (52 in each group) were included. Among all patients, WAZ (-0.9 vs 0.3, P < 0.001) and BMIZ (0 vs 0.6, P < 0.001) improved while HAZ (-0.9 vs -0.9, P = 0.4) did not. Compared to children on OMT, children on VAD experienced greater increases in WAZ (0.8 vs 0.3, P < 0.001) and BMIZ (0.7 vs 0.2, P < 0.003) at HT. The prevalence of moderate-to-severe malnutrition decreased in VAD patients (40% to 19%, P < 0.001) and increased in OMT patients (37% to 46%, P < 0.001), leading to a lower prevalence of moderate-to-severe malnutrition at HT (19% vs 46%, P = 0.003).

CONCLUSIONS

Malnutrition is common in pediatric HT candidates. Compared to children on OMT, children on VAD support had greater improvement in nutritional status while awaiting HT, and a lower prevalence of malnutrition at HT.

Obesity in patients with end-stage heart failure

Obesity poses an increasing problem in patients with end-stage heart failure (HF). The most commonly used indicator of obesity is body mass index. The value of this parameter is widely taken into consideration when selecting the best way of treatment for patients with advanced HF. The aim of this paper is to outline the recent knowledge about obesity in the abovementioned group of patients.

Impact of Change in Body Mass Index on Outcomes After Left Ventricular Assist Device Implantation in Obese Patients

Obesity could be a risk factor portending a poor prognosis after left ventricular assist device (LVAD) implantation. We sought to determine the impact of change in body mass index (BMI) on outcomes in obese patients supported by LVAD. Fifty-nine patients, who received LVAD between January 2010 and June 2015, with BMI ≥30 kg/m at the time of LVAD implantation, were retrospectively analyzed. Patients were divided into two groups based upon whether BMI after 6 months of device support decreased when compared with before. Thirty-eight patients who experienced decrease in BMI (group D) were compared with 21 patients whose BMI increased (group I). Baseline characteristics were similar between the groups except for body weight and BMI, which were significantly higher in group D (BMI: 35.9 ± 4.0 kg/m vs. 33.4 ± 3.5 kg/m; p = 0.018). During mean follow-up of 560 ± 178 days, group I had significantly higher incidence of infection [events per patient-years (eppy): nondevice related: 0.18 vs. 0.35, p = 0.01; device related: 0.1 vs. 0.32, p < 0.01; sepsis: 0.1 vs. 0.32, p < 0.01], heart failure (eppy: 0.1 vs. 0.25, p < 0.01), and renal failure (eppy: 0.03 vs. 0.14, p < 0.01). Survival at 2 years was significantly lower in group I (84.8% vs. 57.1%, p = 0.025). Increase in BMI in obese patients on LVAD is associated with worse survival with a higher incidence of infection, heart failure, and renal failure. Weight control may be a modifiable factor to improve prognosis.

Implications of obesity in cardiac surgery: pattern of referral, physiopathology, complications, prognosis

A U-shaped relationship between body mass index (BMI) and outcomes emerged after cardiac surgery. This review analyses the physio pathologic basis of obesity related complications and evaluates prognostic implications. Both leaner and morbid obese should be considered pre-operatively rather than reactively and, when referred for elective surgery, should undergo a focused metabolic status management, and a thorough evaluation of health status. Adherence to sound surgical principles, and tailored patient blood management and perioperative care are mandatory.

Elevated Body Mass Index Is Not a Risk Factor for Adverse Outcomes Following Ventricular Assist Device Implantation

BACKGROUND

Despite ventricular assist devices (VADs) becoming more common in heart failure (HF) treatment, it is still uncertain which patients are more prone to complications. One potential risk factor is increased body mass index (BMI), which is known to increase both all-cause mortality and mortality from ischemic heart disease; however, the role of the BMI in predicting morbidity and mortality following device implantation is unclear.

METHODS

The study population for this single-institution retrospective chart review consisted of 136 patients with HF, who underwent VAD implantation between 2004 and 2015. Patients were divided into 2 groups based on their BMI: a nonobese group (18.5 < BMI < 30.0; n = 82) or an obese group (BMI >30.0; n = 54). These groups were compared at baseline and after implantation for survival, hospital readmission, and adverse events.

RESULTS

No significant difference was found in initial hospital length of stay, number or length of readmissions, or readmission diagnosis. At 1 year, rates of ongoing device support, orthotopic heart transplant (OHT), and death were not significantly different between groups ( P = .89, P = .90, and P = .70, respectively). Multivariate analysis did not identify obesity as an independent predictor of mortality ( P = .90); only biventricular assist device implantation was associated with decreased survival (hazard ratio [HR] = 5.90, P = .002).

CONCLUSION

Obesity in itself should not preclude the use of VAD support in patients with HF, as carefully selected obese patients were shown to have similar rates of hospital readmission, 1-year outcomes, and survival following device implantation compared to nonobese patients.

Oxygen Consumption at Anaerobic Threshold Predicts Cardiac Events After Heart Transplantation

OBJECTIVES

The ventilatory efficiency and functional capacity measured by the cardiopulmonary exercise test (CPET) have been used as important prognostic variables in congestive heart failure. This study sought to identify whether these predictors before heart transplantation (HTX) play a key role in predicting adverse events in patients with heart failure after HTX.

METHODS

This was a retrospective cohort study design. HTX recipients were included for analysis. Ventilation to carbon dioxide production slope (VE/VCO₂ slope) and oxygen consumption (VO₂) during exercise were collected by CPET, which represented ventilator efficiency and functional capacity respectively. Cardiac-related events 2 years after HTX were recorded by chart review. We divided patients into 2 groups based on VE/VCO₂ slope = 34, peak VO₂ = 14 mL/kg/min and VO₂ at aerobic threshold (AT) = 11 mL/kg/min. Kaplan-Meier survival curves was used to represent the events rate between groups and Log rank test was used to test significance.

RESULTS

A total of 87 patients after HTX were included. Mean (SD) age was 48 (11) years and 73 were male; 28 subjects suffered from events, and 76 cardiac events were recorded. The mean (SD) data of peak VO₂, VO₂ at AT, and VE/VCO₂ slope analyzed from CPET were 17.8 (5.6) mL/kg/min, 15.4 (4.4) mL/kg/min, and 33.1 (8.2) mL/kg/min, respectively. Lower VO₂ at AT contributed to increase events rate (P < .05).

CONCLUSION

Aerobic capacity may better predict 2-year cardiac events in patients after HTX. Strategies to improve aerobic capacity should be focused on in the cohort.

No Obesity Paradox in Pediatric Patients With Dilated Cardiomyopathy

OBJECTIVES

This study aimed to examine the role of nutrition in pediatric dilated cardiomyopathy (DCM).

BACKGROUND

In adults with DCM, malnutrition is associated with mortality, whereas obesity is associated with survival.

METHODS

The National Heart, Lung, and Blood Institute-funded Pediatric Cardiomyopathy Registry was used to identify patients with DCM and categorized by anthropometric measurements: malnourished (MN) (body mass index [BMI] <5% for age ≥2 years or weight-for-length <5% for <2 years), obesity (BMI >95% for age ≥2 years or weight-for-length >95% for <2 years), or normal bodyweight (NB). Of 904 patients with DCM, 23.7% (n = 214) were MN, 13.3% (n=120) were obese, and 63.1% (n=570) were NB.

RESULTS

Obese patients were older (9.0 vs. 5.7 years for NB; p < 0.001) and more likely to have a family history of DCM (36.1% vs. 23.5% for NB; p = 0.023). MN patients were younger (2.7 years vs. 5.7 years for NB; p < 0.001) and more likely to have heart failure (79.9% vs. 69.7% for NB; p = 0.012), cardiac dimension z-scores >2, and higher ventricular mass compared with NB. In multivariable analysis, MN was associated with increased risk of death (hazard ratio [HR]: 2.06; 95% confidence interval [CI]: 1.66 to 3.65; p < 0.001); whereas obesity was not (HR: 1.49; 95% CI: 0.72 to 3.08). Competing outcomes analysis demonstrated increased risk of mortality for MN compared with NB (p = 0.03), but no difference in transplant rate (p = 0.159).

CONCLUSIONS

Malnutrition is associated with increased mortality and other unfavorable echocardiographic and clinical outcomes compared with those of NB. The same effect of obesity on survival was not observed. Further studies are needed investigating the long-term impact of abnormal anthropometric measurements on outcomes in pediatric DCM. (Pediatric Cardiomyopathy Registry; NCT00005391).

The impact of extreme obesity on outcomes after left ventricular assist device implantation

Background

The association between extreme body mass index (BMI) and outcomes in left ventricular assist device (LVAD) patients has not been well established. With the commercial use of LVADs a larger number of patients with a BMI >40 have undergone device implantation. The purpose of this study was to evaluate the short and long-term outcomes of LVAD patients with extreme obesity.

Methods

A retrospective review of all patients (n=383) at our center who received a LVAD as primary implant between 2005-2015 was performed. Demographics, preoperative laboratory values, and postoperative outcomes were analyzed. Patients were divided into three groups based on BMI (kg/m²) classification (group 1: ≤25; group 2: 25 to 35; group 3: ≥35) and compared using one-way analysis of variance (ANOVA), Kruskal-Wallis and Chi-squared analysis as appropriate.

Results

Comparison of postoperative outcomes demonstrated an increased risk of respiratory failure and right ventricular (RV) failure in patients with a BMI ≥35 (range, 35-59). Length of stay, sternal infection, driveline/pocket infection, systemic infection, GI-bleeding, and neurological events within the first year of device therapy were not related to BMI. Survival at 30-day, 1- and 2-year was not significantly different among the three groups. The group with the smallest BMI demonstrated an increased risk for re-operative bleeding.

Conclusions

Despite an increased risk of early morbidity in patients with extreme obesity, long term survival was not significantly different between the BMI groups. Careful consideration is recommended when evaluating patients with an excessive BMI for LVAD therapy although it should not be a contraindication for device placement.

High-Fat Diet-Induced Obesity Enhances Allograft Rejection

BACKGROUND

Obesity promotes a state of low-grade inflammation that exacerbates chronic inflammatory diseases, such as asthma and inflammatory bowel disease. In transplantation, the survival of organs transplanted into obese patients is reduced compared with allografts in lean recipients. However, whether this is due to increased alloimmunity remains to be addressed conclusively.

METHODS

We used a mouse model of high-fat diet (HFD)-induced obesity and assessed immune responses to allogeneic stimulation in vitro, allogeneic splenocyte immunization in vivo, and allogeneic heart transplantation.

RESULTS

Our results indicate that HFD altered the composition and phenotype of splenic antigen-presenting cells that led to their enhanced capacity to stimulate T cells. Immunization with allogeneic splenocytes in vivo resulted in increased alloreactivity, as determined by IFNγ production. Moreover, cardiac allograft rejection in HFD mice was modestly accelerated compared to aged-matched control animals fed a low-fat diet, correlating with enhanced alloreactive T cell function.

CONCLUSIONS

Our results highlight the increased alloresponse triggered by HFD-induced obesity and its negative impact on transplant outcome.

Medical Weight Loss Treatment Options in Obese Solid-Organ Transplant Candidates

With the increasing incidence of obesity in our country, the rate of obesity seen in organ transplant candidates is also rising. Accurate descriptions and measures of weight and degree of obesity vary between organ systems. Weight loss can be achieved in some patients while they wait for the transplant surgery. Weight reduction in transplant candidates involves a team approach, with a program of education and support, including medical nutrition therapy, physical therapy, and psychological support. The safety and applicability of weight loss medications to assist with pretransplant weight loss is also not well understood. It is not yet well known if weight loss before transplantation will improve posttransplant outcomes. Many questions regarding the treatment of obesity in transplant candidates remain unanswered.

The impact of length and weight on survival after heart transplantation in children less than 24 months of age

Adults, older children, and adolescent patients with a BMI categorized as overweight or obese have decreased survival after HTx. Anthropometric correlates of survival after HTx in infants have not been well defined. In a retrospective analysis of the UNOS registry, patients age 0-24 months were classified according to the WHO height-for-age and weight-for-age norms, as well as arbitrary BMI-for-age percentiles. Outcomes of 1-year survival, conditional long-term survival, and cause-specific mortality were examined. Infants with stunted growth according to the WHO definition had increased risks of early mortality, late mortality, and death due to graft failure after HTx. Secondary analysis of first-year survival demonstrated increased mortality in children who were underweight according to weight-for-age, but a survival disadvantage in the highest BMI-for-age category, likely due to short recumbent length leading to relatively high BMI values. Stunted growth relative to WHO standards predicts mortality following heart transplant in children less than 2 years of age. The association between post-transplant mortality and high BMI-for-age, as demonstrated in older cohorts, was observed in the infant cohort only due to stunting, and not due to overweight classification.

Body habitus in heart failure: understanding the mechanisms and clinical significance of the obesity paradox

The prevalence of obesity among adults and children worldwide has reached epic proportions and has become a major independent risk factor for the development of heart failure (HF), in addition to a contributor of hypertension and cardiovascular disease. The implications of obesity in the development of HF involve adverse effects on cardiac structure and function. Despite all of this, in the setting of chronic HF, excess body mass is associated with improved clinical outcomes, demonstrating the presence of an obesity paradox. In this review, we will discuss the gender differences, global application, potential mechanisms and role of interventions based on fitness and purposeful weight loss as potential therapeutic strategies.

Comparison of Characteristics of Patients Undergoing Heart Transplantation at the Same Hospital in Two Different Time Periods (1997-2012 and 2013-2015)

Heart transplantation (HT) increases at some centers each year and decreases at others. We examined characteristics of patients having HT at the same hospital in 2 different time periods (1997-2012 and 2013-2015) by 2 different surgical groups. We compared certain clinical and morphological finding in 291 patients having HT 1997 to 2012 to finding in 228 other patients having HT from 2013 to 2015. Several significant (p <0.05) differences were found: in the most recent time period (2013-2015) compared to the earlier time period (1997-2012), the mean ages of the men were older (57 years -vs- 55 years); diabetes mellitus was more frequent (37% -vs- 21%); systemic hypertension (by history) was more frequent (59% -vs- 32%); the mean body mass index was higher (29.2 kg/m(2) -vs- 26.5 kg/m(2)), and mean heart weight was lower in both men (509 g -vs- 549 g) and women (422 g -vs- 454 g). There were insignificant (p >0.05) differences in gender, frequency of massive cardiac adiposity, underlying cardiac condition, frequency of coronary heart disease, and frequency of previous insertion of a left ventricular assist device. In conclusion, certain characteristics of patients having HT at one Texas hospital changed in several respects in 2 time periods corresponding to changes in surgeons doing the HTs.

Clinical outcomes in overweight heart transplant recipients

BACKGROUND

Few studies have examined the impact of patient weight on heart transplant (HT) outcomes.

OBJECTIVES

Nine outcomes were compared in 2 groups of HT recipients (N = 347) based on their mean body mass index (BMI) during the first 3 years post-HT.

METHODS

Group 1 consisted of 108 non-overweight patients (BMI <25; mean age 52; 29.6% females; 16.7% minorities). Group 2 consisted of 239 overweight patients (BMI ≥25; mean age 52; 15.9% females; 13.8% minorities). Outcomes were: survival, re-hospitalization, rejections, infections, cardiac allograft vasculopathy (CAV), stroke, renal dysfunction, diabetes, and lymphoma.

RESULTS

Non-overweight patients had shorter survival, were re-hospitalized more days after the HT discharge, and had more lymphoma and severe renal dysfunction. Overweight patients had more CAV, steroid-induced diabetes, and acute rejections.

CONCLUSIONS

Overweight HT patients had better survival, but more rejections, CAV, and diabetes. Non-overweight HT patients had worse survival, plus more re-hospitalization time, lymphoma, and renal dysfunction.

Interaction of obesity and infections

There is evidence that certain infections may induce obesity. Obese persons may also have more severe infections and have compromised response to therapies. The objective of this study is to review the available literature identifying infections that potentially contribute to greater body mass index (BMI) and differential responses of overweight and obese persons to infections. A systematic literature review of human studies examining associations between infections and weight gain, differential susceptibility, severity, and response to prevention and treatment of infection according to BMI status (January 1980-July 2014) was conducted. Three hundred and forty-three studies were eligible for inclusion. Evidence indicated that viral infection by human adenovirus Ad36 and antibiotic eradication of Helicobacter pylori were followed by weight gain. People who were overweight or obese had higher susceptibility to developing post-surgical infections, H1N1 influenza and periodontal disease. More severe infections tended to be present in people with a larger BMI. People with a higher BMI had a reduced response to vaccinations and antimicrobial drugs. Higher doses of antibiotics were more effective in obese patients. Infections may influence BMI, and BMI status may influence response to certain infections, as well as to preventive and treatment measures. These observations have potential clinical implications.

Postoperative weight gain during the first year after kidney, liver, heart, and lung transplant: a prospective study

CONTEXT

Studies of all types of organ transplant recipients have suggested that weight gain, expressed as an increase in body mass index (BMI), after transplant is common.

OBJECTIVES

To describe weight gain during the first year after transplant and to determine risk factors associated with weight gain with particular attention to type of transplant.

DESIGN, SETTING, AND PARTICIPANTS

A prospective study of 502 consecutive organ transplant recipients (261 kidney, 73 liver, 29 heart, 139 lung) to identify patterns of BMI change. Measurements were made during regular outpatient clinical visits at 2, 6, and 12 months after transplant. Data were retrieved from patients' charts and correlated with maintenance corticosteroid doses.

RESULTS

Overall, mean BMI (SD; range) was 23.9 (4.5; 13.6-44.1) at 2 months and increased to 25.4 (4.0; 13.0-42.2) by the end of the first postoperative year. BMI levels organized by World Health Organization categories showed a trend toward overweight/obesity in kidney (53.4%), liver (51.5%), heart (51.7%), and lung (33.1%) patients by 12 months after transplant. BMI changed significantly (P= .05) for all organ types and between all assessment points, except in kidney recipients. Maintenance corticosteroid doses were not a predictor of BMI at 12 months after transplant for most patients.

CONCLUSIONS

Weight gain was common among patients undergoing kidney, liver, heart, and lung transplant; however, many showed BMI values close to normality at the end of the first year after transplant. In most cases, increased BMI levels were related to obesity before transplant and not to maintenance corticosteroid therapy.

Increased Body Mass Index Is Associated with Congestive Heart Failure and Mortality in Adult Fontan Patients

OBJECTIVE

Obesity affects adults with congenital heart disease (CHD). The effect of an increased body mass index (BMI) with respect to morbidity and mortality has not been evaluated in adults with complex CHD. Our objective was to evaluate the effects of increased BMI on heart failure and mortality in univentricular patients who had undergone Fontan palliation.

METHODS

A query of Fontan patients' first appointments at the Washington University Center for Adults with CHD between 2007 and 2014 yielded 79 patients. BMI status as normal (<25 kg/m(2) ), overweight (≥25, <30 kg/m(2) ), and obese (≥30 kg/m(2) ) was established at the patient's first appointment. We analyzed demographics, diuretic requirements, New York Heart Association (NYHA) class, and laboratory values using Student's two-sample t-test and Fisher's exact test. Mortality was assessed via survival curves, and hazard ratios were compiled with proportional hazard modeling.

RESULTS

The recent average BMI was significantly greater in patients with NYHA classes II-IV (29.3 ± 9 kg/m(2) ) compared with asymptomatic patients (24.8 ± 5.1 kg/m(2) , P = .006). Additionally, the average BMI of patients with a high diuretic requirement (≥40 mg/day IV furosemide equivalent) was obese, at 32.15 ± 9.1 kg/m(2) , compared with 25.91 ± 7.3 kg/m(2) for those on no or lower doses of diuretics (P = .009). Eighteen of the 79 patients met an endpoint of death, hospice placement, or cardiac transplant by the study conclusion. Kaplan-Meier analysis from time of first appointment until recent follow-up revealed a significant association between time to combined endpoint and BMI class. Cox proportional hazard modeling with age adjustment yielded a hazard ratio of 3.2 (95% CI 1.096-9.379) for obesity upon first presentation to an adult CHD clinic.

CONCLUSIONS

In patients with univentricular hearts and Fontan palliation, obesity is associated with symptomatic heart failure and mortality.

A retrospective cohort study examining the association between body mass index and mortality in severe sepsis

Body mass index (BMI) is an easily calculated indicator of a patient's body mass including muscle mass and body fat percentage and is used to classify patients as underweight or obese. This study is to determine if BMI extremes are associated with increased 28-day mortality and hospital length of stay (LOS) in emergency department (ED) patients presenting with severe sepsis. We performed a retrospective chart review at an urban, level I trauma center of adults admitted with severe sepsis between 1/2005 and 10/2007, and collected socio-demographic variables, comorbidities, initial and most severe vital signs, laboratory values, and infection sources. The primary outcome variables were mortality and LOS. We performed bivariable analysis, logistic regression and restricted cubic spline regression to determine the association between BMI, mortality, and LOS. Amongst 1,191 severe sepsis patients (median age, 57 years; male, 54.7%; median BMI, 25.1 kg/m(2)), 28-day mortality was 19.9% (95% CI 17.8-22.4) and 60-day mortality was 24.4% (95% CI 21.5-26.5). Obese and morbidly obese patients were younger, less severely ill, and more likely to have soft tissue infections. There was no difference in adjusted mortality for underweight patients compared to the normal weight comparator (OR 0.74; CI 0.42-1.39; p = 0.38). The obese and morbidly obese experienced decreased mortality risk, vs. normal BMI; however, after adjustment for baseline characteristics, this was no longer significant (OR 0.66; CI 0.42-1.03; p = 0.06). There was no significant difference in LOS across BMI groups. Neither LOS nor adjusted 28-day mortality was significantly increased or decreased in underweight or obese patients with severe sepsis. Morbidly obese patients may have decreased 28-day mortality, partially due to differences in initial presentation and source of infection. Larger, prospective studies are needed to validate these findings related to BMI extremes in patients with severe sepsis.

Organ transplant & the psychiatrist: An overview

Organ transplantation has emerged as the saving grace for those who are suffering from end organ disease. Advent of modern surgical procedures and immunosuppressants further decrease morbidity and mortality. Meta-analyses have shown that post-organ transplantation quality of life improves for social, physical and daily activity functioning, but not consistently for psychological health. Psychiatrists can play a useful role not only in selecting the best suitable candidate for the procedure by psychosocial screening but also to tackle post-operation psychological issues that trouble patients as well as caretakers and decrease their quality of life. Issues like selection of patients with psychiatric disorders and substance abuse for transplantation process and their treatment both pre- and post- operation, risky health behaviours, treatment adherence for immunosuppressants and psychological support for caretakers can be better addressed by a psychiatrist who is sensitive towards these issues. Prescribing various psychotropics and immunosuppressants in the background of impaired organ function and drug-drug interaction is further challenging. Thus, psychiatrists need to be knowledgeable about these issues and should be an integral part of organ transplantation team for overall better outcome.

Differential effect of body mass index on pediatric heart transplant outcomes based on diagnosis

The impact of nutritional status on HTx waitlist mortality in children is unknown, and there are conflicting data regarding the role of nutrition in post-HTx survival. This study examined the influence of nutrition on waitlist and post-HTx outcomes in children. Children 2-18 yr listed for HTx from 1997 to 2011 were identified from the OPTN database and stratified by BMI percentile. Multivariable logistic regression evaluated the influence of BMI on waitlist mortality. Cox proportional hazard regression assessed the impact of BMI on post-HTx mortality. When all 2712 patients were analyzed, BMI did not impact waitlist, one-, or five-yr mortality. However, when stratified by diagnosis, BMI > 95% (AOR 1.96; 95% CI 1.24, 3.09) and BMI < 1% (AOR 2.17; 95% CI 1.28, 3.68) were independent risk factors for waitlist mortality in patients with CM. BMI did not impact waitlist mortality in CHD and did not impact post-HTx outcomes, regardless of diagnosis. BMI > 95% and BMI < 1% are independent risk factors for waitlist mortality in patients with CM, but not CHD. This suggests differing risk factors based on disease etiology, and an individualized approach to risk assessment based on diagnosis may be warranted.

Hypoalbuminemia and poor growth predict worse outcomes in pediatric heart transplant recipients

Children with end-stage cardiac failure are at risk of HA and PG. The effects of these factors on post-transplant outcome are not well defined. Using the PHTS database, albumin and growth data from pediatric heart transplant patients from 12/1999 to 12/2009 were analyzed for effect on mortality. Covariables were examined to determine whether HA and PG were risk factors for mortality at listing and transplant. HA patients had higher waitlist mortality (15.81% vs. 10.59%, p = 0.015) with an OR of 1.59 (95% CI 1.09-2.30). Survival was worse for patients with HA at listing and transplant (p ≤ 0.01 and p = 0.026). Infants and patients with congenital heart disease did worse if they were HA at time of transplant (p = 0.020 and p = 0.028). Growth was poor while waiting with PG as risk factor for mortality in multivariate analysis (p = 0.008). HA and PG are risk factors for mortality. Survival was worse in infants and patients with congenital heart disease. PG was a risk factor for mortality in multivariate analysis. These results suggest that an opportunity may exist to improve outcomes for these patients by employing strategies to mitigate these risk factors.

Determinants of noninvasive ventilation outcomes during an episode of acute hypercapnic respiratory failure in chronic obstructive pulmonary disease: the effects of comorbidities and causes of respiratory failure

Objectives. To investigate the effect of the cause of acute respiratory failure and the role of comorbidities both acute and chronic on the outcome of COPD patients admitted to Respiratory Intensive Care Unit (RICU) with acute respiratory failure and treated with NIV. Design. Observational prospective study. Patients and Methods. 176 COPD patients consecutively admitted to our RICU over a period of 3 years and treated with NIV were evaluated. In all patients demographic, clinical, and functional parameters were recorded including the cause of acute respiratory failure, SAPS II score, Charlson comorbidity index, and further comorbidities not listed in the Charlson index. NIV success was defined as clinical improvement leading to discharge to regular ward, while exitus or need for endotracheal intubation was considered failure. Results. NIV outcome was successful in 134 patients while 42 underwent failure. Univariate analysis showed significantly higher SAP II score, Charlson index, prevalence of pneumonia, and lower serum albumin level in the failure group. Multivariate analysis confirmed a significant predictive value for pneumonia and albumin. Conclusions. The most important determinants of NIV outcome in COPD patients are the presence of pneumonia and the level of serum albumin as an indicator of the patient nutritional status.

Abnormal nutrition affects waitlist mortality in infants awaiting heart transplant

BACKGROUND

Although nutritional status affects survival after heart transplant (HTx) in adults and older children, its effect on outcomes in young children is unknown. This study aimed to assess the effect of pre-HTx nutrition on outcomes in this population.

METHODS

Children aged 0 to 2 years old listed for HTx from 1997 to 2011 were identified from the Organ Procurement and Transplantation Network database. Nutritional status was classified according to percentage of ideal body weight at listing and at HTx. Logistic regression analysis evaluated the risk of waitlist mortality. Cox proportional hazard models assessed the effect of nutrition on post-HTx survival.

RESULTS

Of 1,653 children evaluated, 899 (54%) had normal nutrition at listing, 445 (27%) were mildly wasted, 203 (12%) were moderate or severely wasted, and 106 (6%) had an elevated weight-to-height (W:H) ratio. Moderate or severe wasting (adjusted odds ratio, 1.9; 95% confidence interval, 1.3-2.7) and elevated W:H (adjusted odds ratio, 1.7; 95% confidence interval, 1.1-2.6) were independent risk factors for waitlist mortality. HTx was performed in 1,167 patients, and 1,016 (87%) survived to 1-year post-HTx. Nutritional status at listing or at HTx was not associated with increased post-HTx mortality. Nutritional status did not affect the need for early reoperation, dialysis, or the incidences of infection, stroke, or rejection before hospital discharge.

CONCLUSIONS

Moderate or severe wasting and an elevated W:H are independent risk factors for waitlist mortality in patients aged < 2 years but do not affect post-HTx mortality. Optimization of pre-HTx nutritional status constitutes a strategy to reduce waitlist mortality in this age range.

Obesity in heart failure: impact on survival and treatment modalities

Heart failure (HF) and obesity are commonly seen in the USA. Although obesity is associated with traditional cardiovascular disease, its relationship with HF is complex. Obesity is an accepted risk factor for incident HF. However, in patients with established HF, there exists a paradoxical correlation, with escalating BMI incrementally protective against adverse outcomes. Despite this relationship, patients with HF may desire to lose weight to reduce comorbidities or to improve quality of life. Thus far, studies have shown that intentional weight loss in obese patients with HF does not increase risk, with strategies including dietary modification, physical activity, pharmacotherapy, and/or surgical intervention.

Hypertension, obesity, and coronary artery disease in the survivors of congenital heart disease

Obesity, hypertension, and coronary artery disease are prevalent in the general population and well recognized as contributors to cardiac morbidity and mortality. With surgical and medical advances, there is a growing and aging population with congenital heart disease who are also at risk of developing these comorbidities. In addition, some congenital cardiac lesions predispose patients to conditions such as hypertension or coronary artery disease. The effect of these comorbidities on the structurally abnormal heart is not well understood, but might be very important, especially in those with residual abnormalities. Thus, in addition to surveillance for and treatment of late complications it is important for the congenital cardiologist to consider and aggressively manage acquired comorbidities. In this review we explore the prevalence of hypertension, obesity, and coronary artery disease, discuss congenital lesions that predispose to these conditions and review management strategies for this unique population.

Epidemiology and clinical impact of infection in patients awaiting heart transplantation

OBJECTIVES

The aim of this study was to determine the epidemiology and clinical impact of infections in patients awaiting heart transplantation.

METHODS

We evaluated all patients considered for a heart transplant in our center over a period of 18 months over a period of 18 months from 2007 to 2009. The patients were followed up for 8 months or until death, transplant, or loss to follow-up.

RESULTS

Ninety patients were included in the study. During follow-up, 25 infections were recorded in 22 heart transplant candidates (24.4%). Respiratory infections were the most frequent infection (12 bronchitis; 48.0%), followed by skin and soft tissue infections (four infections; 16.0%), intra-abdominal infections (four infectious diarrhea; 16.0%), bacteremia (three infections; 12.0%), and urinary tract infections (two infections; 2.0%). Age, comorbidity, sex, and diabetes were not found to be risk factors for infection. Twenty-four patients (26.7%) were transplanted during follow-up. Infection before transplantation was not associated with an increased risk of mortality or a higher rate of infection in the immediate post-transplant period.

CONCLUSIONS

Infections are common in heart transplant candidates, affecting almost 25% of them. Respiratory tract infections are the most frequent type of infection. However, they are not associated with increased mortality in the immediate post-transplant period.

Bariatric Surgery for a Patient with a Heartmate II Ventricular Assist Device for Destination Therapy

A patient with a HeartMate II left ventricular assist device who had a body mass index of 52 needed gastric bypass surgery in order to qualify for a heart transplant. Unlike previous experience in which the surgery was performed at the implant hospital, the gastric bypass surgery in this case was performed at a bariatric center of excellence that was a separate facility from the implant hospital. The artificial heart program of the University of Pittsburgh Medical Center worked with the bariatric center of excellence in scheduling the gastric bypass surgery using a multidisciplinary team approach at 2 hospitals to coordinate safe, high-quality patient care in a unique situation.

Patient selection for ventricular assist devices: a moving target

The number of patients with advanced heart failure that has become unresponsive to conventional medical therapy is increasing rapidly. One of the most promising new alternatives to heart transplantation is use of ventricular assist devices (VADs). To date, there are no guidelines for appropriate selection for use of these devices that are approved by national societies in the field. This review addresses all of the general criteria for clinicians to keep in mind regarding when to refer a patient for evaluation and the specific issues addressed in patient selection. The field of mechanical circulatory support has advanced significantly over the past 10 years, resulting in rapid expansion of patients with advanced heart failure who can benefit from implantable devices. With progress of technology, limitations associated with age, body size, and comorbidities gradually become less prohibitive. The continuing simplification of design along with continued reduction in size of the devices, plus eventual elimination of the external drive line will make the use of VADs a superior option to heart transplant and even to medical management in many patients. We anticipate that the patient selection process outlined in the present review will continue to shift toward less advanced cases of heart failure.

Combined Ventricular Assist Device Placement With Adjustable Gastric Band (VAD-BAND): A Promising New Technique for Morbidly Obese Patients Awaiting Potential Cardiac Transplantation

Background

Morbid obesity remains a potential relative contraindication for cardiac transplantation. Hence, a select population of morbidly obese patients with end-stage heart failure may require a ventricular assist device (VAD) as a bridge to transplantation to afford them time to lose sufficient weight and thus decrease there mortality rate after transplantation. Unfortunately, obtaining suitable weight loss via dietary or exercise regimens is limited by the cardiac limitations of the patients. We report on a new procedure of combining ventricular assist device placement with adjustable gastric band (VAD-BAND) placement to facilitate sufficient weight loss for cardiac transplantation.

Methods

We report on our experience of 2 morbidly obese (BMI 46.6, BMI 43.7) patients with severe non-ischemic cardiomyopathy who underwent a VAD-BAND placement for treatment of morbid obesity and potential future cardiac transplantation.

Results

Patient 1 was a 24-year-old male with a body mass index (BMI) of 46.6 admitted in cardiogenic shock with severe non-ischemic cardiomyopathy (New York Functional Class IV, Left Ventricular Ejection Fraction 15.3%) who underwent the VAD-BAND procedure. At 11 months outpatient follow-up the patient had clinically improved with a BMI of 34.2. Patient 2 was a 36-year-old male with a body mass index of 43.7 admitted in cardiogenic shock with severe non-ischemic cardiomyopathy (New York Functional Class IV, Left Ventricular Ejection Fraction 17.1%) who underwent placement of a VAD-BAND. At 4 months post-operation, the patient was stalwart clinically with a BMI of 34.8. Both patients are now under consideration for cardiac transplantation.

Conclusion

In conclusion, concurrent placement of a VAD-BAND is a safe and viable option for morbidly obese patients with end-stage heart disease. Further research is needed to define indications and future clinical practice.

Keywords

Gastric band; Ventricular assist device; Morbid obesity; Heart failure; Transplantation; Weight loss