Bionic women and men - Part 4: Cardiovascular, cerebrovascular and exercise responses among patients supported with left ventricular assist devices.

Current generation left ventricular assist devices (LVADs) have led to significant improvements in survival compared to medical therapy alone, when used for management of patients with advanced heart failure. However, there are a number of side-effects associated with LVAD use, including hypertension, gastrointestinal bleeding, stroke, as well as persistent and severe limitations in functional capacity despite normalization of a resting cardiac output. These issues are, in large part, related to chronic exposure to a non-physiologic pulse, which contributes to a hyperadrenergic environment characterized by markedly elevated levels of sympathetic nerve activity through a baroreceptor-mediated pathway. In addition, these machines are unable to participate in, or contribute to, normal cardiovascular/autonomic reflexes that attempt to modulate flow through the body. Efforts to advance device technology and develop biologically sensitive devices may resolve these issues, and lead to further improvements in quality-of-life, functional capacity, and ultimately, survival, for the patients they support.