TWINNING PROGRAM WITH ESTONIA, LATVIA, AND LITHUANIA

Richard Schoephoerster of Florida International University first hosted Vladimir Kasyanov of the Medical Academy of Latvia in the spring of 2000. The visit launched their investigation of an artificial heart valve design that incorporates a composite material of polypropylene threads embedded in a polymer substrate, with the thread architecture mimicking in vivo collagen architecture. A total of twelve prototype artificial valves were produced. The valves were then mounted in the aortic position of a left heart systemic circulation simulator and pressures and flows from the valves were recorded and compared. The data suggests that the material they were testing, polystyrene-polyisobutylene-polystyrene (SIBS), may be a viable candidate material for synthetic flexible membrane trileaflet valves. During Kasyanov's visit to Florida, several students were also trained in materials handling and valve fabrication methods.

Schoephoerster's visit to Latvia in August 2000 allowed him to meet and interact with several key colleagues who will likely be involved in future work. An important product of this year's work was a joint application for a grant from the American Heart Association entitled "In Vitro Performance of a Novel Trileaflet Synthetic Heart Valve." In addition, the scientists, with the owner of the SIBS material, plan to submit a proposal to the National Institutes of Health to focus on the initial studies necessary to bring the valve to the marketplace.

Update—2001

Following on their successful exchange of visits in 2000, Schoephoerster welcomed Kasyanov for a two-week visit in March-April 2001. During the visit, the colleagues worked on a proposal to the National Institutes of Health SBIR program to support their ongoing collaboration, in partnership with Dr. Leonard Pinchuk of Syntheon, Inc. In May 2001, they were pleased to learn that a proposal prepared and submitted during Kasyanov’s visit in 2000 had been funded. The grant from the American Heart Association (AHA) in the amount of $120,000 began in July 2001 and supports their work on vitro performance characterization of a novel trileaflet synthetic heart valve.

Kasyanov made his second visit of the year from late August to late December 2001, an extended stay made possible thanks to the new AHA grant. During the visit, the colleagues worked on characterizing the mechanical properties of the composite polymer material to be used in the valve, fabricating valves, characterizing their in vitro performance, and determining valve leaflet stress distributions using computational finite element analysis. The results of their work have already been presented at the International Mechanical Engineering Congress and Exposition (New York, November 2001) and the Sixth Annual Hilton Head Workshop on Prosthetic Heart Valves (March 2002). Making use of a no-cost extension through 2002, Schoephoerster plans to host Kasyanov again in August 2002, and in conjunction with that visit the two specialists anticipate presenting their findings at the World Congress of Biomechanics in Calgary. They are still awaiting word on the outcome of their NIH proposal and have also been advised to look into the possibility of applying to NSF as well.