Poster 004: Access-Related Vascular and Bleeding Complications of Impella Support and Their Impact on Outcomes: A National Inpatient Sample 2018–2022 Analysis

Background: Impella devices are increasingly utilized for temporary mechanical circulatory support in patients with cardiogenic shock; however, access-related vascular and bleeding complications remain understudied at a national level. We evaluated the prevalence of these complications and their association with in-hospital outcomes among Impella-supported hospitalizations in the United States.

Methods: We conducted a retrospective cohort study using the National Inpatient Sample (NIS) from 2018–2022, identifying adult hospitalizations (≥18 years) involving Impella support. Patients were stratified based on the presence or absence of access-related vascular or bleeding complications, including acute limb ischemia, pseudoaneurysm, arteriovenous fistula, retroperitoneal hematoma, post-procedural bleeding, device-related complications, and hemolysis. Primary outcomes included in-hospital mortality, length of stay, total hospital charges. Secondary outcomes included sepsis, stroke, blood transfusion, and lower extremity amputation. Survey-weighted multivariable logistic and linear regression models were used to adjust for demographics, comorbidities, hospital characteristics, and temporal trends.

Outcome: Among 106,570 Impella-supported hospitalizations, access-related complications occurred in 19.4%. The most frequent were device-related complications (13.7%), acute limb ischemia/arterial thrombosis (2.7%), post-procedural bleeding (2.3%), and retroperitoneal hematoma (1.0%). Compared with patients without complications, those with complications had higher unadjusted in-hospital mortality (34% vs 28%), longer median LOS (9 vs 6 days), and higher median total charges ($445,159 vs $333,826; all p< 0.001). After adjustment, access complications were associated with increased in-hospital mortality (aOR 1.32, 95% CI 1.22–1.43) with an absolute mortality increase (AME) of 5.7 percentage points (95% CI 4.0–7.3), as well as higher odds of stroke (aOR 1.54, 95% CI 1.32–1.79), sepsis (aOR 1.39, 95% CI 1.26–1.53), and blood transfusion (aOR 1.44, 95% CI 1.31–1.58) (all p< 0.001). LOS was 29% longer (LOS ratio 1.29, 95% CI 1.22–1.37; β +3.66 days, 95% CI 3.06–4.26) and charges were 26% higher (charge ratio 1.26, 95% CI 1.23–1.30; β +$149,611, 95% CI $126,334–$172,888). Lower-extremity amputation was uncommon overall (0.46%) but more frequent with access complications (unadjusted OR 2.60, 95% CI 1.73–3.92, p< 0.001).

Conclusion: Access-related vascular and bleeding complications affect nearly one in five Impella-supported hospitalizations and are independently associated with higher mortality, systemic complications, prolonged hospitalization, and increased healthcare costs. These findings underscore the importance of meticulous vascular access strategies, early complication recognition, and targeted protocols to improve outcomes in Impella-supported shock patients.