Defining cost-effectiveness of mechanical circulatory support escalation among patients with acute myocardial infarction complicated by cardiogenic shock

Background: Temporary mechanical circulatory support (MCS) for acute myocardial infarction complicated by cardiogenic shock (AMI-CS) includes microaxial-flow pumps (mFP), venoarterial extracorporeal membrane oxygenation (VA-ECMO), and combined mFP-ECMO support. These strategies differ substantially in haemodynamic capability and resource use, but their short-term cost-effectiveness has not been compared within a common decision framework. Methods: We developed a 4-strategy decision-analytic model comparing No MCS (standard care without temporary MCS), mFP, VA-ECMO, and mFP-ECMO from the perspective of a publicly funded Australian health system over 30 days. Costs were estimated from individual resource components in 2025?26 Australian dollars and benchmarked against hospital casemix data. The primary outcome was cost per additional 30-day survivor. Scenario analyses and probabilistic sensitivity analysis assessed parameter uncertainty. Results: Expected per-patient costs were A$34,562 for No MCS, A$125,269 for mFP, A$133,573 for VA-ECMO, and A$177,481 for mFP-ECMO. Assigned 30-day survival probabilities were 56.1%, 74.2%, 54.3%, and 53.9%, respectively. mFP was the only non-dominated MCS strategy, with an incremental cost-effectiveness ratio of A$502,695 per additional survivor compared with No MCS. Under the assigned cross-cohort inputs, VA-ECMO and mFP-ECMO were more costly and less effective, remained strictly dominated across all prespecified scenarios, and required 30-day survival above 74.2% to escape dominance. Intensive care unit (ICU) bed-days were the largest cost component. At a willingness-to-pay threshold of A$500,000 per additional survivor, the probabilities of being optimal were 44.0% for No MCS, 54.1% for mFP, 1.7% for VA-ECMO, and 0.2% for mFP-ECMO. Conclusions: Under the assigned cross-cohort inputs, escalation of MCS beyond mFP in AMI-CS increased costs without improving modelled 30-day survival. Nevertheless, VA-ECMO and mFP-ECMO remain essential for selected patients requiring greater circulatory or respiratory support.