Mortality With Impella Is Lowest in Overweight and Obese but Is Highest in Morbid Obesity.

Introduction: Mortality of cardiogenic shock remains high, prompting increased use of mechanical circulatory support devices such as Impella. This study sought to characterize whether weight categories predict mortality in patients who received Impella devices.

Methods: We used data from the National Inpatient Sample (NIS) database from the years 2016 to 2020 and ICD-10-CM/PCS codes to evaluate the effect of weight categories on mortality in patients undergoing Impella implantation.

Results: A total of 86 810 patients underwent Impella device implantation, with an overall mortality of 29.85%. Mortality for normal weight was 30.4%, similar to cachexia (30.3%) and morbidly obese patients (31.1%). However, the overweight and obese categories had the lowest mortality (13.4% and 24.9%, p < 0.0001). Using multivariate analysis adjusting for comorbid conditions, overweight and obesity remained significantly associated with the lowest mortality (overweight: OR: 0.3, CI: 0.16-0.68, p = 0.003, Obese: OR: 0.8, CI: 0.71-0.91, p < 001) whereas morbid obesity was associated with the highest mortality (OR: 1.17, CI: 1.02-1.34, p = 0.02).

Conclusion: Using a large database, we found that overweight and obesity have a protective effect on mortality in patients undergoing Impella insertion. However, morbid obesity appears to have detrimental effects.