title: Optimal pressure regulation of the pneumatic ventricular assist device with bellows-type driver.
abstract: The bellows-type pneumatic ventricular assist device (VAD) generates pneumatic pressure with compression of bellows instead of using an air compressor. This VAD driver has a small volume that is suitable for portable devices. However, improper pneumatic pressure setup can not only cause a lack of adequate flow generation, but also cause durability problems. In this study, a pneumatic pressure regulation system for optimal operation of the bellows-type VAD has been developed. The optimal pneumatic pressure conditions according to various afterload conditions aiming for optimal flow rates were investigated, and an afterload estimation algorithm was developed. The developed regulation system, which consists of a pressure sensor and a two-way solenoid valve, estimates the current afterload and regulates the pneumatic pressure to the optimal point for the current afterload condition. Experiments were performed in a mock circulation system. The afterload estimation algorithm showed sufficient performance with the standard deviation of error, 8.8 mm Hg. The flow rate could be stably regulated with a developed system under various afterload conditions. The shortcoming of a bellows-type VAD could be handled with this simple pressure regulation system.
authors.affiliation: Korea Artificial Organ Center, Korea University Medical College, Seoul, Korea.
authors.forename: Jung Joo
authors.initials: JJ
authors.lastname: Lee
authors.forename: Bum Soo
authors.initials: BS
authors.lastname: Kim
authors.forename: Jaesoon
authors.initials: J
authors.lastname: Choi
authors.forename: Hyuk
authors.initials: H
authors.lastname: Choi
authors.forename: Chi Bum
authors.initials: CB
authors.lastname: Ahn
authors.forename: Kyoung Won
authors.initials: KW
authors.lastname: Nam
authors.forename: Gi Seok
authors.initials: GS
authors.lastname: Jeong
authors.forename: Choon Hak
authors.initials: CH
authors.lastname: Lim
authors.forename: Ho Sung
authors.initials: HS
authors.lastname: Son
authors.forename: Kyung
authors.initials: K
authors.lastname: Sun
mesh_terms: D000465:Algorithms; D004867:Equipment Design; D006353:Heart-Assist Devices; D006801:Humans; D008955:Models, Cardiovascular; D011312:Pressure