Effects of Interaction Between Ventricular Assist Device Assistance and Autoregulated Mock Circulation Including Frank–Starling Mechanism and Baroreflex

Abstract

A mock heart circulation loop (MHCL) is a hydraulic model simulating the human circulatory system. It allows in vitro investigations of the interaction between cardiac assist devices and the human circulatory system. In this study, a preload sensitive MHCL, the MHCL , was developed to investigate the interaction between the left ventricle and left ventricular assist devices (LVADs). The Frank-Starling mechanism was modeled by regulating the stroke volume (SV) based on the measured mean diastolic left atrial pressure (MLAP ). The baroreflex autoregulation mechanism was implemented to maintain a constant mean aortic pressure (MAP) by varying ventricular contractility (E ), heart rate (HR), afterload/systemic vascular resistance (SVR) and unstressed venous volume (UVV). The DP3 blood pump (Medos Medizintechnik GmbH) was used to simulate the LVAD. Characteristic parameters were measured in pathological conditions both with and without LVAD to assess the hemodynamic effect of LVAD on the MHCL . The results obtained from the MHCL show a high correlation to literature data. The study demonstrates the possibility of using the MHCL as a research tool to better understand the physiological interactions between cardiac implants and human circulation.

The Progress in the Novel Pediatric Rotary Blood Pump Sputnik Development

“…This system allows reproducing the Frank‐Starling autoregulation mechanism of the heart, which regulates the cardiac output depending on the ventricle preload parameter that can be expressed as end‐diastolic pressure (EDP), end‐diastolic volume (EDV), or mean left atrial pressure like in Ref. .…”

In-vitro investigation of the hemodynamic responses of the cerebral, coronary and renal circulations with a rotary blood pump installed in the descending aorta

“…For this study the preload (Frank-Starling mechanism) and afterload (autonomic nervous system) sensitivity of the ventricles were not modelled in the SCVL. Preload and afterload sensitive motors have been implemented into other cardiovascular simulators [25,26,28]. Implementation of these features in the SCVL is necessary to give a more comprehensive understanding of the hemodynamic effects of an RBP device in the DA.…”

“…In recent years, much progress has been made in the design and development of cardiovascular simulators with close similarity to a native system for research and training [25][26][27][28].…”

Finite state machine implementation for left ventricle modeling and control

“…1 [12, 21, 30, 38]. However, for the purpose of repeatability within a MCS, the culmination of this knowledge can be summarized by simplifying the performance of the LV through three principal factors: preload, afterload, and contractility [24, 25]. These have significant implications on VAD performance [39].…”

“…Their research concluded that the elastance-based model performed more realistically when reproducing specific cardiovascular scenarios and that many MCS designs could be considered inadequate, if careful consideration is not made to the pumping action of the ventricle. Subsequent in vitro testing utilizing this control approach successfully reproduced an elastance mechanism of a natural ventricle by mimicking preload and afterload sensitivity [25]. Preload was modified by means of manually changing the fluid content of the closed loop hydraulic circuit, while afterload was varied by increasing or decreasing the systemic arterial resistance within a modified Windkessel model.…”