The invention relates to a transcatheter heart valve replacement (A61F2/2412), and in particular to a side delivered large diameter, low profile transcatheter prosthetic valve having a compressible tubular frame having a side wall and a central axial lumen, said tubular frame having a height of 8-20 mm and a diameter of 40-80 mm, an atrial sealing cuff, a subannular anchoring component, and aa flow control component comprising a leaflet structure, wherein the valve is side-delivered longitudinally to a mitral valve annulus or tricuspid valve annulus of a patient using a 22-34 Fr delivery catheter.