Enhanced external counterpulsation treatment improves lower extremity hemodynamics and wall shear stress metrics in diabetic foot

As a non-invasive assisted circulation therapy, enhanced external counterpulsation (EECP) has been shown to improve local perfusion and wall shear stress (WSS) metrics in the healthy femoral artery bifurcation. However, the effects of EECP on the distal vasculature and in patients with lower-extremity arterial disease (LEAD) remain unclear. This study evaluates EECP-induced hemodynamic variations in patients with LEAD using in vivo measurements and numerical simulations. Six diabetic foot (DF) patients with lower-extremity arterial lesions were enrolled. Bilateral lower-extremity arterial models were reconstructed from magnetic resonance angiography, and Doppler ultrasound was performed to obtain blood-flow velocity spectra before and during EECP. Three-dimensional patient-specific numerical models were developed to quantitatively assess variations in WSS-derived hemodynamic metrics. EECP significantly increased both antegrade and retrograde blood flow volumes in the common femoral artery and superficial femoral artery compared with the pre-EECP condition. Numerical results revealed a significant increase in the time-averaged wall shear stress throughout the lower-extremity arteries and a corresponding reduction in relative resident time, while the oscillatory shear index remained unchanged. These findings confirm the hemodynamic benefits of EECP in patients with DF, which may underpin improvements in cardiovascular and neurological functions of the lower limbs. The proper clinical benefits will be exhibited in our further work based on an ongoing clinical control trial.