You bring up a medical ethics questions that have gone to court to determine liability or lack thereof.
"The meaning of a do not resuscitate (DNR) order is radically altered for a patient who is mechanically ventilated and supported with an LVAD, for the chronic treatment of these patients already surpasses the measures envisioned by advanced cardiac life support protocols. To enact a DNR order for a patient receiving LVAD support suggests withdrawing, and not merely withholding, care. Although ethicists have for many years insisted that there is no ethical difference between withdrawing and withholding treatments, many physicians still believe that there is a profound psychological difference between the two [8]. However, there are compelling reasons to view withdrawing and withholding care as morally equivalent. One such justification is described in the landmark case Barber v Los Angeles County Superior Court:
Thanks for the interesting question. Take care.