Examination of the Dynamic Behaviour of Cardiac Support Systems

Challenge

Ventricular assist devices (VADs) are available for late-stage heart failure. These are usually implanted to bridge the gap until heart transplantation is performed.

Conditions

• A VAD is a mechanical pump which takes over the function of the left or right ventricle or both ventricles
• Most commonly, a Left Ventricular Assist Device (LVAD) is used to assist the left ventricle
• The device is implanted in the apex of the heart. It sucks the oxygen-rich blood - which the heart can no longer pump into the body - out of the left ventricle and then pumps it into the aorta via an artificial duct called graft
• The control unit and battery are located outside the body - the cardiac pump is connected to them by a connecting cable

Scope

Development of reliable, patient-adapted VAD systems

Task

Simulation of a VAD system to investigate the dynamic behaviour as a function of the control and geometry parameters at specified maximum pressures

Solution

• Development of a hydraulic-pneumatic ventricular model
• Setup of simulation models for the pneumatic actuation and the hydraulic representation of the body
• Verification of the sub-models and combining them into an integrated simulation model
• Simulation of the VAD system with different control settings