title: A system for in-vitro characterization of heart valve bioprostheses under accelerated fatigue conditions and under physiologic conditions.
abstract: An accelerated fatigue testing system and a pulse duplicator (heart simulator) were used in a set-up in which pressure differences and pulsatile flow rates across prosthetic heart valves, as well as machine rates, could be measured using a real-time on-line data-acquisition system. With this information available, an immediate in-vitro characterization of the fluid dynamics of prosthetic heart valves could be obtained under both physiologic and accelerated conditions. In addition to the fatigue tester and the pulse duplicator, a signal conditioner, a DC amplifier, an analog-to-digital converter, and a digital microcomputer comprised the essential hardware. For the purpose of this study, special acquisition software was developed. By means of the same computational algorithms, all quantitative fluid dynamics data could be calculated using information from both the pulse duplicator and the fatigue tester, so that direct comparisons and correlations could be approached. Pressure difference-flow rate relationships for the two machines were comparable.
authors.affiliation: University of Medicine and Dentistry of New Jersey, Department of Cardiothoracic Surgery, Newark 07103-2757.
authors.forename: M C
authors.initials: MC
authors.lastname: Iosif
authors.forename: S
authors.initials: S
authors.lastname: Gabbay
mesh_terms: D001705:Bioprosthesis; D003199:Computer Systems; D004867:Equipment Design; D005069:Evaluation Studies as Topic; D006350:Heart Valve Prosthesis / Q000592:standards*; D008422:Materials Testing; D008838:Microcomputers; D009862:Online Systems; D011312:Pressure; D011474:Prosthesis Design; D011673:Pulsatile Flow; D012984:Software; D014159:Transducers