Does "obesity paradox" apply for patients undergoing transcatheter aortic valve replacement?

Update on antithrombotic therapy and body mass: a clinical consensus statement of the European Society of Cardiology Working Group on Cardiovascular Pharmacotherapy and the European Society of Cardiology Working Group on Thrombosis

Obesity and underweight are a growing health problem worldwide and a challenge for clinicians concerning antithrombotic therapy, due to the associated risks of thrombosis and/or bleeding. This clinical consensus statement updates a previous one published in 2018, by reviewing the most recent evidence on antithrombotic drugs based on body size categories according to the World Health Organization classification. The document focuses mostly on individuals at the extremes of body weight, i.e. underweight and moderate-to-morbid obesity, who require antithrombotic drugs, according to current guidelines, for the treatment or prevention of cardiovascular diseases or venous thromboembolism. Managing antithrombotic therapy or thromboprophylaxis in these individuals is challenging, due to profound changes in body composition, metabolism and organ function, and altered drug pharmacokinetics and pharmacodynamics, as well as weak or no evidence from clinical trials. The document also includes artificial intelligence simulations derived from in silico pharmacokinetic/pharmacodynamic models, which can mimic the pharmacokinetic changes and help identify optimal regimens of antithrombotic drugs for severely underweight or severely obese individuals. Further, bariatric surgery in morbidly obese subjects is frequently performed worldwide. Bariatric surgery causes specific and additional changes in metabolism and gastrointestinal anatomy, depending on the type of the procedure, which can also impact the pharmacokinetics of antithrombotic drugs and their management. Based on existing literature, the document provides consensus statements on optimizing antithrombotic drug management for underweight and all classes of obese patients, while highlighting the current gaps in knowledge in these complex clinical settings, which require personalized medicine and precision pharmacology.

Obesity and Transcatheter Aortic Valve Replacement

Amidst an aging population and escalating obesity prevalence, elucidating the impact of obesity on transcatheter aortic valve replacement (TAVR) outcomes becomes paramount. The so-called "obesity paradox"-a term denoting the counterintuitive association of obesity, typically a risk factor for cardiovascular diseases, with improved survival outcomes in TAVR patients relative to their leaner or normal-weight counterparts-merits rigorous examination. This review comprehensively investigates the complex relationship between obesity and the clinical outcomes associated with TAVR, with a specific focus on mortality and periprocedural complications. This study aims to deepen our understanding of obesity's role in TAVR and the underlying mechanisms of the obesity paradox, thereby optimizing management strategies for this patient demographic, tailored to their unique physiological and metabolic profiles.

Body Mass Index and Outcomes of Transcatheter Aortic Valve Replacement: A Retrospective Observational Study

The influence of body mass index (BMI) on Transcatheter Aortic Valve Replacement (TAVR) outcomes has been the focus of several previous studies. In this study, we examined the relationship between BMI and various clinical outcomes following TAVR procedures. A comprehensive analysis was conducted using a large cohort of patients who underwent TAVR. In this study, we identified patients who underwent Transcatheter aortic valve replacement (TAVR) in the year 2020. Procedure Classification System (ICD-10-PCS) codes were used to identify TAVR cases. The weighted final study sample included 77319 TAVR hospitalizations. Patients were categorized into 5 groups based on their Body Mass Index (BMI. Our findings revealed that there was no significant difference in in-hospital mortality among different BMI groups when compared to patients with a normal BMI (20 to 24.9). patients with a BMI of 25 or higher demonstrated a statistically significant shorter duration of hospitalization compared to those with a normal BMI. patients with a BMI ranging between 30 and 39.9 exhibited decreased hospitalization costs when compared to patients with a normal BMI. Moreover, our study revealed a decrease in atrial fibrillation, acute heart failure and acute kidney injury complications following TAVR in patients with above-normal BMI. Despite similar in-hospital mortality across BMI groups, having a BMI of 25 or greater is associated with improved immediate outcomes following TAVR. These benefits in overweight and obese patients are consistent with findings described in recent literature. Further studies are warranted to explore the underlying mechanisms and potential implications of these associations, as well as to optimize patient selection and management strategies for TAVR procedures.

Midterm Outcomes of Underweight Patients Undergoing Transcatheter Aortic Valve Implantation: Insight From the LAPLACE-TAVR Registry

Background

Obesity is a major risk factor for cardiovascular disease; however, a paradoxical effect of obesity has been reported in patients with heart failure or myocardial infarction. Although several studies have suggested the same obesity paradox in patients undergoing transcatheter aortic valve replacement (TAVR), they included a limited number of underweight patients.

Objectives

This study aimed to clarify the effect of being underweight on TAVR outcomes.

Methods

We retrospectively analyzed 1,693 consecutive patients undergoing TAVR between 2010 and 2020. The patients were categorized according to body mass index: underweight (<18.5 kg/m²; n = 242), normal weight (18.5 to 25 kg/m²; n = 1,055), and overweight (>25 kg/m²; n = 396). We compared midterm outcomes after TAVR among the 3 groups; all clinical events were in accordance with the Valve Academic Research Consortium-2 criteria.

Results

Underweight patients were more likely to be women and have severe heart failure symptoms, peripheral artery disease, anemia, hypoalbuminemia, and pulmonary dysfunction. They also had lower ejection fractions, smaller aortic valve areas, and higher surgical risk scores. Device failure, life-threatening bleeding, major vascular complications, and 30-day mortality occurred more frequently in underweight patients. The midterm survival rate of the underweight group was inferior to those of the other 2 groups (P < 0.0001; average follow-up, 717 days). In the multivariate analysis, underweight was associated with noncardiovascular mortality (HR: 1.78; 95% CI: 1.16-2.75) but not cardiovascular mortality (HR: 1.28; 95% CI: 0.58-1.88) after TAVR.

Conclusions

Underweight patients had a worse midterm prognosis, demonstrating the obesity paradox in this TAVR population. (Outcomes of transcatheter aortic valve implantation in Japanese patients with aortic stenosis: multi-center registry; UMIN000031133).

Effect of BMI on patients undergoing transcatheter aortic valve implantation: A systematic review and meta-analysis

BACKGROUND

The relationship of body mass index (BMI) and an "obesity paradox" with cardiovascular risk prediction is controversial. This systematic review and meta-analysis aims to compare the associations of different BMI ranges on transcatheter aortic valve implantation (TAVI) outcomes.

METHODS

International databases, including PubMed, the Web of Science, and the Cochrane Library, were systematically searched for observational and randomized controlled trial studies investigating TAVI outcomes in any of the four BMI categories: underweight, normal weight, overweight, and obese with one of the predefined outcomes. Primary outcomes were in-hospital, 30-day, and long-term all-cause mortality. Random-effects meta-analysis was performed to calculate the odds ratio (OR) or standardized mean differences (SMD) with 95% confidence interval (CI) for each paired comparison between two of the BMI categories.

RESULTS

A total of 38 studies were included in our analysis, investigating 99,829 patients undergoing TAVI. There was a trend toward higher comorbidities such as hypertension, diabetes, and dyslipidemia in overweight patients and individuals with obesity. Compared with normal-weight, patients with obesity had a lower rate of 30-day mortality (OR 0.42, 95% CI 0.25-0.72, p < 0.01), paravalvular aortic regurgitation (OR 0.63, 95% CI 0.44-0.91, p = 0.01), 1-year mortality (OR 0.48, 95% CI 0.24-0.96, p = 0.04), and long-term mortality (OR 0.69, 95% CI 0.51-0.94, p = 0.02). However, acute kidney injury (OR 1.16, 95% CI 1.04-1.30, p = 0.01) and permanent pacemaker implantation (OR 1.25, 95% CI 1.05-1.50, p = 0.01) odds were higher in patients with obesity. Noteworthy, major vascular complications were significantly higher in underweight patients in comparison with normal weight cases (OR 1.62, 95% CI 1.07-2.46, p = 0.02). In terms of left ventricular ejection fraction (LVEF), patients with obesity had higher post-operative LVEF compared to normal-weight individuals (SMD 0.12, 95% CI 0.02-0.22, p = 0.02).

CONCLUSION

Our results suggest the presence of the "obesity paradox" in TAVI outcomes with higher BMI ranges being associated with lower short- and long-term mortality. BMI can be utilized for risk prediction of patients undergoing TAVI.

Heart valve surgery and the obesity paradox: A systematic review

Obesity has been associated with increased incidence of comorbidities and shorter life expectancy, and it has generally been assumed that patients with obesity should have inferior outcomes after surgery. Previous literature has often demonstrated equivalent or even improved rates of mortality after cardiac surgery when compared to their lower-weight counterparts, coined the obesity paradox. Herein, we aim to review the literature investigating the impact of obesity on surgical valve interventions. PubMed and Embase were systematically searched for articles published from 1 January 2000 to 15 October 2021. A total of 1315 articles comparing differences in outcomes between patients of varying body mass index (BMI) undergoing valve interventions were reviewed and 25 were included in this study. Patients with higher BMI demonstrated equivalent or reduced rates of postoperative myocardial infarction, stroke, reoperation rates, acute kidney injury, dialysis and bleeding. Two studies identified increased rates of deep sternal wound infection in patients with higher BMI, although the majority of studies found no significant difference in deep sternal wound infection rates. The obesity paradox has described counterintuitive outcomes predominantly in coronary artery bypass grafting and transcatheter aortic valve replacement. Recent literature has identified similar trends in other heart valve interventions. While the obesity paradox has been well characterized, its causes are yet to be identified. Further study is essential in order to identify the causes of the obesity paradox so patients of all body sizes can receive optimal care.