Abstract: A polymer valve and a ventricular assist device using the polymer valve are provided to allow blood to flow in a first direction but prevents blood from flowing backward in a second direction opposite to the first direction. The polymer valve comprises a base body having a hollow therethrough for passing of blood, comprising a pair of support legs formed by cutting opposing sides of an end portion of the base body along an inclined surface toward the center line of the hollow to extend toward the first direction from the body , and a leaflet formed of polymer and attached to the support legs to cover the hollow, wherein the leaflet includes a pair of opposing sides attached to the cutting surfaces of the support legs and an end portion connecting the sides of the leaflet, wherein the leaflet is formed of an opening between the support legs.

Abstract: A prosthetic blood valve comprises a base body having a hollow, opposing props extending from the body to partition opposing inclined ridges of the body to allow the inclined ridges and each top of the props to define the hollow and to form an upper surface of the body, and a singular leaflet attached to and along the inclined ridges and the prop tops to cover the hollow. The singular leaflet has a substantially central opening between the props and formed of a flexible material so a forward or outward blood flow passes through the opening and a reverse flow or backflow of blood leads to opposing leaflet portions around the opening being abuttingly pulled to each other to thereby prevent the blood backflow.