Vascular Function in Continuous-Flow Left Ventricular Assist Device Recipients: Effect of a 6-Week Pulsatility Treatment Regimen

Vascular function is further diminished in chronic heart failure patients implanted with a continuous‐flow left ventricular assist device (LVAD), which contributes to vascular‐related adverse events. A single pulsatility treatment has been documented to recover vascular function, however, the impact of a chronic treatment regimen is unknown. Methods Eleven LVAD recipients and ten well‐matched controls, received unilateral, 45‐minute, arm pulsatility treatment, created by intermittent cuff inflation and deflation (2‐second duty cycle), distal to the elbow, three days a week for 6 weeks. Vascular function was assessed by percent brachial artery flow mediated dilation (%FMD) (Doppler ultrasound). Results At baseline, %FMD was not different between LVAD recipients (4.2±0.3%) and controls (4.4±0.4 %), while LVAD recipients exhibited an attenuated %FMD/Shear (LVAD: 0.09±0.01; Controls: 0.14±0.01 %/s −1 , p<0.05) and a longer time‐to‐peak dilation (LVAD: 85±6; Controls: 51±5 s, p<0.05). Pulsatility index (PI) was lower in the LVAD recipients compared to controls (LVAD: 2±1; Controls: 13±2 AU, p<0.05). Importantly, during the pulsatility treatment, the PI level was not different between groups (LVAD: 28±5; Controls: 34±5 AU). Although time‐to‐peak dilation was not altered by 6‐weeks of pulsatility treatment, %FMD (LVAD: 7.9±0.5; Controls: 7.3±0.7 %) and %FMD/Shear (LVAD: 0.16±0.02; Controls: 0.26±0.03 %/s −1 ) improved significantly. Notably, %FMD/Shear in the LVAD recipients recovered to the baseline level of controls. All measures returned to baseline levels after a 6‐week washout period. Conclusions A 6‐week pulsatility treatment regimen restored vascular function in LVAD recipients, demonstrating the efficacy of a pulsatility targeted intervention to potentially mitigate vascular related adverse events in this population. Support or Funding Information COI: Dr. Stavros G. Drakos serves on the Steering Committee of the Abbott‐sponsored INTELLECT‐2 LVAD. Funding: This research was supported by the National Institutes of Health (1T322HL13945, R01HL118313) and the U.S. Veteran’s Administration (E6910‐R, E1697‐R, E1433‐P, E9275‐L, E1572‐P, and I01RX001311).