Cost analysis of microaxial flow pump (Impella) versus standard care in cardiogenic shock: findings from the danger shock trial

Background

Mechanical circulatory support with a microaxial flow pump (mAFP, Impella CP) improved 180-day survival in ST-segment elevation myocardial infarction complicated by cardiogenic shock (STEMI-CS) in the Danger Shock trial, but was associated with higher complication rates and longer hospitalisation.

Purpose

To evaluate the cost consequences of routine Impella CP therapy in STEMI-CS, including in-hospital costs, intensive care utilisation, and post-discharge resource consumption through 180 days.

Methods

This prespecified within-trial detailed cost analysis was conducted alongside the international, multicentre, open-label, randomised DanGer Shock trial. The cost analysis was performed from a hospital perspective with a 180-day time horizon using an intention-to-treat approach.

Index hospitalisation costs were estimated using a micro-costing approach based on prospectively collected patient-level resource utilization and follow-up data, whereas post-discharge hospital contacts within 180 days were valued using national diagnosis-related group tariffs. Costs were compared between mAFP plus standard care and standard care alone, and incremental cost differences were estimated with non-parametric bootstrapping (10,000 replications) to derive 95 % confidence intervals (CI).

Results

A total of 355 patients with STEMI-CS were randomised to mAFP plus standard care (n=179) or standard care alone (n=176). Patients in the mAFP group had longer median intensive care unit (ICU) stay (6 days, interquartile range (IQR) 2-15 vs 3 IQR 0-10), longer general ward stay (3 days IQR 0-11 vs 1 IQR 0-8), and received more advanced respiratory and monitoring interventions (Figure 1). Patients in the mAFP group further received more blood transfusions, but fewer additional PCI procedures before discharge and fewer heart-failure-related rehospitalisations within 180 days.

Mean total index hospitalisation costs were €84,842 (SD ±96,296) in the mAFP group and €46,003 (SD ±75,516) in the standard-care group (Δ €38,839; 95 % CI 21,586-56,896). The difference was primarily driven by higher costs of mechanical circulatory support devices and procedures (Δ €20,768; 95 % CI 13,102-28,947), hospital admission including ICU (Δ €16,121; 95 % CI 4,351-28,065), and in-hospital events and complications (Δ €1,247; 95 % CI 126-2,334).

During 180-day follow-up, post-discharge costs did not differ significantly between groups: mean €2,059 (SD ±12,300) in the mAFP group vs €3,384 (SD ±28,594) in the standard-care group (Δ −€1,324; 95 % CI -6,585-2, 406).

Conclusion

Routine use of mAFP in STEMI-CS was associated with significantly higher index hospitalisation costs, primarily driven by ICU stays and device-related resource use. Post-discharge 180-day costs were similar between groups. These findings inform implementation of Impella therapy in publicly funded healthcare systems.Figure 1Cost breakdown by treatment group