Related Experiment Videos
Right ventricular assist system feedback flow control parameter for a rotary blood pump
M Yoshikawa1, K I Nakata, K Nonaka
1Baylor College of Medicine, Houston, Texas, USA; and University of Vienna, Vienna, Austria.
Artificial Organs
|September 6, 2000
Summary
An implantable right ventricular assist system (RVAS) showed excellent hemodynamics during exercise in calves. Heart rate and oxygen uptake are feasible feedback parameters for RVAS flow control.
Area of Science:
- Cardiovascular Engineering
- Medical Devices
- Hemodynamics
Background:
- Right ventricular failure affects 25-30% of patients with left ventricular assist devices (LVADs).
- Development of implantable biventricular assist systems (BiVAS) is ongoing.
- Simultaneous development of right ventricular assist systems (RVAS) with rotary blood pumps is needed.
Purpose of the Study:
- To evaluate the hemodynamics and exercise response of a nonpulsatile implantable RVAS.
- To investigate the feasibility of controlling RVAS flow during exercise.
Main Methods:
- An implantable RVAS was tested in a calf during 30 minutes of treadmill exercise (1.5 mph).
- Hemodynamic parameters (pulmonary artery flow, heart rate, right atrial pressure) and blood gas analysis (oxygen uptake, delivery, extraction) were recorded.
- Two pump flow groups (low assist <3.5 L/min, high assist >3.5 L/min) were compared.
Main Results:
- RVAS maintained excellent hemodynamics during exercise, with increased pulmonary artery flow, heart rate, and right atrial pressure.
- Oxygen uptake and delivery increased during exercise; higher oxygen delivery was observed in the high assist group.
- RVAS flow rates remained unchanged, necessitating a flow control system.
Conclusions:
- The implantable RVAS demonstrated effective hemodynamic support during exercise.
- Heart rate and oxygen uptake are feasible feedback parameters for developing a closed-loop control system for implantable RVAS.