Microcirculatory Hemodynamic Changes on Full Support Microaxial Flow Pump in Cardiogenic Shock

Impaired microcirculation predicts mortality in cardiogenic shock independent of systemic hemodynamics, yet current treatment strategies focus primarily on restoring macrocirculatory markers. We studied whether full-support microaxial flow pump (mAFP) therapy improves sublingual microcirculation in cardiogenic shock. A prospective, single-arm, observational study of serial sublingual microcirculation imaging via incident darkfield handheld videomicroscopy was performed in 18 cardiogenic shock patients undergoing Impella 5.5 (mAFP) placement. Microvascular flow index (MFI), microvascular heterogeneity index (MHI), proportion of perfused vessels (PPV), and perfused vessel density (PVD) were measured. Eighteen patients were enrolled. Microvascular flow index (p = 0.004), MHI (p = 0.055), PPV (p = 0.003), and PVD (p = 0.067) improved immediately on support, including when adjusted for vasoactive-inotropic score. Improvement in MFI, MHI, PPV, or PVD was most pronounced in those with impaired baseline microcirculatory hemodynamics (all p < 0.05), whereas those with preserved baseline values demonstrated no change. Improved agreement between systemic and microcirculatory hemodynamics was observed in association with mAFP support, and none experienced worsening microcirculatory function. These exploratory findings suggest full-support mAFPs may improve impaired microcirculation during cardiogenic shock, although device-specific effects cannot be isolated from overall clinical improvement; validation in larger studies is warranted. Although agreement between systemic and microcirculatory hemodynamic markers improved, no macrohemodynamic marker proved sufficient to ensure adequate microcirculatory perfusion.