A stent valve device for delivery by catheter to a vessel site in the body, comprising: a radially expandable cylindrical stent, the radially expandable cylindrical stent having a collapsed configuration for delivery and an expanded configuration for deployment at the vessel site, the radially expandable cylindrical stent having a proximal stent end, a distal stent end, a stent lumen, and a stent diameter and a stent perimeter, a valve located within the lumen of the radially expandable cylindrical stent, the valve comprising biocompatible material and at least two leaflets, the valve having a valve orifice between the at least two leaflets, the valve orifice extending substantially across the stent diameter, wherein (a) the valve has a proximal portion connected to a proximal portion of the radially expandable cylindrical stent and a distal portion connected to a distal portion of the radially expandable cylindrical stent; (b) at the locations between adjacent leaflets, the valve orifice terminates 1 to 5 millimeters before reaching the perimeter of the radially expandable cylindrical stent; (c) the valve material is enclosed within the radially expandable cylindrical stent; characterized in that (d) reinforcement mechanisms are located between the orifice perimeter and the stent perimeter at the locations between adjacent leaflets at valve-stent-opening connection points; thereby reinforcing said connection points against wear and tear due to opening and closing of the valve and permitting increased structural integrity of the stent valve device. a radially expandable cylindrical stent, the radially expandable cylindrical stent having a collapsed configuration for delivery and an expanded configuration for deployment at the vessel site, the radially expandable cylindrical stent having a proximal stent end, a distal stent end, a stent lumen, and a stent diameter and a stent perimeter, a valve located within the lumen of the radially expandable cylindrical stent, the valve comprising biocompatible material and at least two leaflets, the valve having a valve orifice between the at least two leaflets, the valve orifice extending substantially across the stent diameter, wherein (a) the valve has a proximal portion connected to a proximal portion of the radially expandable cylindrical stent and a distal portion connected to a distal portion of the radially expandable cylindrical stent; (b) at the locations between adjacent leaflets, the valve orifice terminates 1 to 5 millimeters before reaching the perimeter of the radially expandable cylindrical stent; (c) the valve material is enclosed within the radially expandable cylindrical stent; characterized in that (d) reinforcement mechanisms are located between the orifice perimeter and the stent perimeter at the locations between adjacent leaflets at valve-stent-opening connection points; thereby reinforcing said connection points against wear and tear due to opening and closing of the valve and permitting increased structural integrity of the stent valve device. (a) the valve has a proximal portion connected to a proximal portion of the radially expandable cylindrical stent and a distal portion connected to a distal portion of the radially expandable cylindrical stent; (b) at the locations between adjacent leaflets, the valve orifice terminates 1 to 5 millimeters before reaching the perimeter of the radially expandable cylindrical stent; (c) the valve material is enclosed within the radially expandable cylindrical stent; characterized in that (d) reinforcement mechanisms are located between the orifice perimeter and the stent perimeter at the locations between adjacent leaflets at valve-stent-opening connection points; thereby reinforcing said connection points against wear and tear due to opening and closing of the valve and permitting increased structural integrity of the stent valve device.