Outcomes of microaxial flow pump mechanical circulatory support in cardiogenic shock

Background Microaxial flow pump percutaneous ventricular assist devices are increasingly utilised in cardiogenic shock (CS) and complex high-risk indicated percutaneous coronary intervention (CHIP). However, real-world outcome data, particularly in heterogeneous aetiologies and across the spectrum of Society for Cardiovascular Angiography and Interventions (SCAI) shock stages, remain limited. We report outcomes from a large consecutive cohort of patients supported with microaxial flow pump devices at two tertiary hospitals. Methods We retrospectively analysed consecutive patients who received microaxial flow pump support (January 2018–February 2026) at two tertiary hospitals. Baseline demographics, haemodynamics, procedural characteristics, and outcomes were collected. The primary endpoint was 30-day all-cause mortality. Secondary endpoints included myocardial recovery/device weaning, escalation to durable left ventricular assist device (LVAD) or heart transplantation, and procedural complications. Results A total of 268 patients were included in our analysis. Their median age was 56 years (interquartile range [IQR] 43–63), and the majority of them (75.7%) were male. The most frequent indications were ST-elevation myocardial infarction (STEMI; 36.2%), dilated cardiomyopathy with acute decompensated heart failure (DCM-ADHF; 24.3%), non-ST-elevation acute coronary syndrome (NSTE-ACS; 12.3%), and acute myocarditis (10.8%). The majority presented in SCAI stage ≥D (67.2%), and 33.2% had cardiac arrest. Concomitant percutaneous coronary intervention (PCI) was performed in 54.1%, with complete revascularisation achieved in 41.3% of PCI cases. Median duration of microaxial flow pump support was 5 days (IQR 1–9). Thirty-day all-cause mortality was 45.5% (101/222). Myocardial recovery with successful device weaning was achieved in 76.4% (68/89) of evaluable patients. Bridge to durable LVAD occurred in 7.8% and heart transplantation in 5.2% of patients. Access-site complications occurred in 7.3%, and haemodynamic instability/loss of pulsatility during support was observed in 27.3%. Conclusions In this large two-centre experience, microaxial flow pump support was used predominantly in patients with advanced cardiogenic shock (SCAI ≥D) from diverse aetiologies. Despite the high acuity, with two-thirds in SCAI stage D–E and one-third post-cardiac arrest, myocardial recovery was achieved in over three-quarters of evaluable patients. These findings underscore the role of microaxial flow pump as a bridge to recovery, durable device, or transplantation in a real-world cardiogenic shock population.