Aortic Valve Function Under Support of a Left Ventricular Assist Device: Continuous vs. Dynamic Speed Support

Selim Bozkurt*, Frans N. van de Vosse, Marcel C. M. Rutten

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


Continuous flow left ventricular devices (CF-LVADs) support the failing heart at a constant speed and alters the loads on the aortic valve. This may cause insufficiency in the aortic valve under long-term CF-LVAD support. The aim of this study is to assess the aortic valve function under varying speed CF-LVAD support. A Medtronic freestyle valve and a Micromed DeBakey CF-LVAD were tested in a mock circulatory system. First, the CF-LVAD was operated at constant speeds between 7500 and 11,500 rpm with 1000 rpm intervals. The mean pump outputs obtained from these tests were applied in varying speed CF-LVAD support mode using a reference model for the pump flow. The peak of the instantaneous pump flow was applied at peak systole and mid-diastole, respectively. Ejection durations and in the aortic valve were the longest when the peak pump flow was applied at mid-diastole among the CF-LVAD operating modes. Furthermore, mean aortic valve area over a cardiac cycle was highest when the peak pump flow was applied at mid-diastole. The results show that changing phase of the reference flow rate signal may reduce the effects of the CF-LVADs on altered aortic valve closing behavior, without compromising the overall pump support level.
Original languageEnglish
Pages (from-to)1727-1737
JournalAnnals of Biomedical Engineering
Issue number8
Publication statusPublished - Aug 2015


  • Aortic valve
  • Aortic valve insufficiency
  • Aortic valve area
  • Varying speed CF-LVAD support

Cite this