Abdominal adiposity assessed using CT angiography associates with acute kidney injury after trans-catheter aortic valve replacement

A Meta-Analysis on the Impact of High BMI in Patients Undergoing Transcatheter Aortic Valve Replacement

BACKGROUND

A paradoxical association of obesity with lower risk of transcatheter aortic valve replacement (TAVR) outcomes has been reported. We aimed to systematically review the literature and compare TAVR-related morbidity and mortality among individuals with overweight or obesity and their peers with normal body mass index (BMI).

METHODS

PubMed and Embase databases were systematically searched for studies reporting TAVR outcomes in different BMI groups. Separate meta-analyses were conducted for studies reporting hazard ratios (HR) and odds ratios/relative risks. Short- and mid-/long-term outcomes were examined.

RESULTS

26 studies with a total of 74,163 patients were included in our study. Overweight was associated with lower risk of short-term mortality (HR: 0.77; 95% CI: 0.60-0.98) and mid-/long-term mortality (HR: 0.79; 95% CI: 0.70-0.89). Obesity was associated with lower risk for mid-/long-term mortality (HR: 0.79; 95% CI: 0.73-0.86), but no difference was observed in short-term mortality, although a trend was noted (HR: 0.87l 95% CI: 0.74-1.01). Individuals with obesity demonstrated an association with higher odds of major vascular complications (OR: 1.33; 95% CI: 1.05-1.68). Both overweight (OR: 1.16; 95% CI: 1.03-1.30) and obesity (OR: 1.26; 95% CI: 1.06-1.50) were associated with higher likelihood for receiving permanent pacemakers after TAVR.

CONCLUSION

Individuals with overweight and obesity were associated with lower mortality risk compared to those with normal BMI but with higher likelihood of major vascular complications and permanent pacemaker implantation after TAVR.

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

BACKGROUND

Data is controversial regarding the existence of an "obesity paradox" in patients undergoing Transcatheter Aortic Valve Replacement (TAVR). We sought to investigate the prognostic value of the body mass index (BMI) on outcomes following TAVR.

METHODS

This is an observational, single-center study involving all patients who underwent TAVR from 2009 to 2019. BMI was calculated in all patients before TAVR. The cohort was subdivided into four groups: underweight (<20 kg/m²), normal weight (≥20 to <25 kg/m²), overweight (≥25 to <30 kg/m²) and obese (≥30 kg/m²). The main endpoint was all-cause 30-day and one-year mortality.

RESULTS

A total of 412 patients (mean age 79.6 ± 7.8 years, mean STS score 5.3 ± 3.6) were included. Patients were grouped as follows: underweight (n = 35, 8.5%), normal weight (n = 121, 29.4%), overweight (n = 140, 34%) and obese (n = 116, 28.1%). Obese patients were younger, included more females and had lower STS score than the rest of the cohort whereas underweight patients were older, had higher STS score, more chronic kidney disease, more left ventricular dysfunction and more often underwent non-transfemoral TAVR. BMI predicted 30-day survival (AUC:0.692 [95%CI 0.522-0.862]; p = 0.030) with an optimal cut-off of 24.4 (sensitivity = 66.6%, specificity = 63.6%). On multivariate analysis, higher BMI trended toward lower 30-day mortality (HR = 0.87 [95%CI 0.75-1.01]; p = 0.071). Thirty-day mortality was higher in the underweight group (8.3%) in comparison with other BMI subgroups (normal weight 2.5%, overweight 1.4%, obese 0.9%; p = 0.045). However, no significant difference was found after adjustment of confounders (all p = NS). BMI did not predict one-year mortality. No significant difference in one-year survival was observed between the four BMI subgroups (log rank p = 0.925).

CONCLUSION

BMI could represent an interesting prognostic tool for short-term mortality in patients undergoing TAVR. BMI < 20 kg/m² was associated with higher 30-day mortality. Symptoms improved similarly in obese patients compared to lower BMI patients. For 30-day survivors, no evidence of the existence of an obesity paradox was observed in this cohort.