Summary: | The development of a prototype extra-aortic balloon cuff with peristaltic motion and counterpulsation system is explored to investigate the practical feasibility for potential future treatments for chronic heart failure. This concept is an extension of an existing clinical heart assisting device called C-Pulse® created by Sunshine Heart which is used to treat patients with New York Heart Association Class III and ambulatory Class IV heart failure. Both software simulation and hardware-based experimental work are undertaken. The software simulation of a one-dimensional pressure wave propagation through an aortic segment and the influence of an external peristaltic movement are explored using Matlab® (MathWorks®, United States). Simulation results show characteristic differences between a normal pressure waveform and an augmented waveform. The hardware work was divided into three parts - development of a phantom aorta, cardiovascular simulation platform, and the peristaltic extra-aortic balloon cuff prototype. A phantom aorta was made from Dragon Skin® 10 with geometries and properties similar to that of the biological physiological human aorta. A devised cardiovascular simulation platform with the phantom aorta attached was constructed and utilised as a testing platform for the functionality of the peristaltic extra-aortic balloon cuff prototype. The prototype was developed using an Arduino based microcontroller which drives four pneumatic pumps that inflate and deflate extra-aortic balloon cuffs, attached to the descending aorta, in a counterpulsating manner to the natural heartbeat. The peristaltic extra-aortic balloon cuff prototype was able to significantly increase the mean aortic pressure from ~92 mmHg to ~96 mmHg (P<0.05). The flow velocity waveform in the ascending aorta was also altered - increasing the mean diastolic flow from 13.47 cm/s to 17.73 cm/s (P<0.05).
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