Microaxial Flow Pumps in Heart Failure-Related Cardiogenic Shock-From Hemodynamic Mechanisms to Clinical Applications: A State-of-the-Art Review.

BACKGROUND: Heart failure-related cardiogenic shock (HF-CS) is now the leading etiology of cardiogenic shock (CS). Advances in temporary mechanical circulatory support (tMCS), particularly microaxial flow pumps (mAFP), alongside evolving organ procurement and heart-allocation policies, have expanded opportunities for hemodynamic stabilization, recovery, and heart replacement therapy. However, prolonged support capabilities have increased the complexity of clinical decision-making in a heterogeneous population with variable candidacy for heart replacement therapies if native heart recovery (NHR) is not achieved. Optimal use of mAFP requires integration of device-specific capabilities with patient-level hemodynamics and overall clinical context.

METHODS AND RESULTS: This state-of-the-art review synthesizes the epidemiology and pathophysiology of HF-CS, the integration of hemodynamic profiling into clinical management, and contemporary clinical evidence for mAFP use. Although DanGer Shock demonstrated a mortality benefit of Impella CP in acute myocardial infarction-related cardiogenic shock (AMI-CS), extrapolation of these findings to HF-CS is limited by distinct pathophysiologic substrates and ongoing device evolution. Newer surgically implanted platforms, such as the axillary Impella 5.5, provide high-capacity, sustained left ventricular unloading while preserving patient mobility, thereby extending support strategies beyond short-term stabilization, and enabling bridge-to-decision and bridge-to-replacement pathways in select patients. Observational data suggest that prompt recognition of shock severity and timely initiation of support are associated with improved outcomes, and multicenter registries that include HF-CS cohorts have refined our understanding of patient selection, device utilization, and timing of mAFP support in real-world practice. However, marked variability in patient phenotype, practice patterns, and ongoing device evolution complicates evidence interpretation. Within this context, pulmonary artery catheter (PAC)-guided hemodynamic profiling may be central to informing initial device selection and timing and enabling serial trajectory assessment to guide escalation and weaning.

CONCLUSION: Advances in mAFP technology have broadened the therapeutic armamentarium for HF-CS, but significant opportunities for innovation in device design and implementation remain. Optimal outcomes depend on early shock recognition and frequent, comprehensive assessment of hemodynamic and clinical trajectory. Efforts to optimize patient selection and reduce device-related complications must be coupled with systems that enable rapid deployment and effective biventricular support when indicated. Future investigations should prioritize phenotype-specific trials and hemodynamic-guided algorithms to refine device selection and improve outcomes.