Project Abstract
Left ventricular assist device support is standard therapy for patients with advanced, life-threatening heart failure.
However, current-generation impeller-based blood pumps have introduced a new “non-pulsatile” physiology with
frequent adverse events. Lack of pulsatility contributes to blood trauma, endothelial and arterial remodeling, and
abnormalities in vasoregulation that predispose patients to bleeding, thrombosis, diastolic hypertension, and
stroke. Cyclic speed modulation in which device impeller speed is rapidly increased/decreased has been
developed to generate pulsatile blood flow. This emerging technology has potential to combine durability of
impeller-driven devices with physiologic benefits of pulsatility in order to reduce adverse events and improve
quality of life for patients with artificial circulation devices. To date, no investigation has characterized
(patho)physiologic effects of total-body pulsatile versus non-pulsatile blood flow with the same device. The
BiVACOR total artificial heart is a first-of-its-kind, impeller-based total artificial heart with the ability to generate
continuous (non-pulsatile) or pulsatile blood flow through cyclic impeller speed modulation. In a chronic bovine
model, we propose to investigate in vivo effects of non-pulsatile versus pulsatile flow with the BiVACOR on blood
trauma, arterial remodeling, and vasoregulation. We anticipate that compared to non-pulsatile support, pulsatile
flow will 1) reduce blood trauma, 2) prevent pathologic changes in endothelial and arterial wall architecture and
function, and 3) maintain normal vasoregulation during postural changes, transition to exercise, sleep, and other
activities of daily living. Data will provide insight into pathophysiologic mechanisms of adverse events in patients
with impeller-based blood pumps. Findings will also be useful for the development of artificial pulsatility
algorithms that mimic physiologic pulsatility in order to minimize blood trauma, prevent arterial remodeling, and
appropriately modulate vasomotor tone during daily activities.
