Color digital photograph of two Starr-Edwards heart valve prototypes, ball-and-cage design. The right-hand one does not have the cloth suture ring.

Color digital photograph of two Starr-Edwards heart valve prototypes with ball-and-cage design standing beside ruler for scale.

Color digital photograph of two Starr-Edwards heart valve prototypes, ball-and-cage design with three struts in the cage. Left-hand valve has an opaque oscillating ball.

Color digital photograph of two Starr-Edwards heart valve prototypes with plastic ball-and-cage design. One standing and one lying next to a ruler for scale.

Color digital photograph of a pair of hands hold two Starr-Edwards heart valve prototypes, ball-and-cage design. The left-hand valve cage is slightly more elongated than [...]

Color digital photograph of three Starr-Edwards heart valve prototypes, ball-and-cage design, standing beside a ruler for scale. The right-hand valve has a plastic cage, [...]

Color digital photograph of three Starr-Edwards heart valve prototypes, ball-and-cage design, lying beside a ruler for scale.

Color digital photograph of three Starr-Edwards ball-and-cage heart valve prototypes standing beside a ruler for scale. Plastic design on the righthand side, the central [...]

Color digital photograph of three Starr-Edwards heart valve prototypes lying beside a ruler for scale. Valves are ball-and-cage design with the central valve showing the [...]

Color digital photograph of three Starr-Edwards heart valve prototypes lying beside a ruler. Valves are ball-and-cage design from right to left they are plastic, metal an [...]