Impact of age and body mass index (BMI) on the short-term prognosis of Impella in patients with cardiogenic shock

Abstract

Abstract Introduction The percutaneous transcatheter left ventricular assist device, Impella, has been recently introduced in Japan for patients with drug refractory acute heart failure including cardiogenic shock (CGS). Despite its potential benefits, Impella is associated with certain limitations, including a large device size and an increased risk of complications such as bleeding, hemolysis, and renal failure. These factors may present challenges for the use of Impella in elderly patients and those with smaller body size. For elderly patients with various comorbidities, the clinical impact of invasive hemodynamic support with impella remains unclear. Objective To assess the impact of age and body mass index (BMI) on the survival of patients with CGS treated with Impella. Methods We retrospectively reviewed 133 consecutive patients, who received Impella for cardiogenic shock, including cardiac arrest, between September 2018 and January 2023 at our institute. Patients were divided into two distinct age groups: younger group (<75 years of age; n=59) and elderly group (≥75 years; n=74). We assessed rate of successful Impella weaning and the 30-day survival. Multivariate cox regression analysis was used to identify risk factors for 30-day all-cause mortality. Results Baseline patient characteristics demonstrated a mean age of 70 ±13 years with 71% male ratio. Acute coronary syndrome was diagnosed in 72% of patients, while 63% received concomitant venoarterial extracorporeal membrane oxygenation (VA-ECMO), called ECPELLA, and 41% underwent extracorporeal cardiopulmonary resuscitation (E-CPR). The elderly group exhibited a lower BMI and higher rates of comorbidities, such as hypertension and chronic kidney disease. Notably, the incidence of cardiac arrest, E-CPR, and concomitant use of VA-ECMO were significantly lower in the elderly group compared with the younger group. There were no significant differences in Impella weaning, support duration, and length of hospital stay among two groups. Kaplan-Meier analysis revealed that the 30-day survival was also similar between two groups. Univariable Cox regression analysis revealed that BMI was significantly associated with 30-day mortality along with E-CPR and the combined use of VA-ECMO. Multivariable Cox regression analysis including the age, male, BMI, E-CPR, and combined use of VA-ECMO showed that the predictive values of independent determinants for 30-day mortality were age (hazard ratio [HR] 1.05, 95% confidence interval [CI], 1.02-1.07, P<0.0001), BMI (HR 1.14, 95%CI, 1.06-1.21, P=0.0001), and VA-ECMO (HR 4.27, 95% CI, 1.92-9.50, P=0.0004). Conclusion Results suggest that age and BMI were significantly associated with increased 30-day mortality risk, indicating a counterintuitive relationship between BMI and mortality in this population.OutcomesMultivariate Cox Regression