A valvulotome device for cutting valves inside a lumen of a vein having a deployable assembly with deployable cutting blades and guide fins which permit continual centralizing, self-alignment of the cutting blades within the lumen of the vein as the valves are being excised is disclosed. The valvulotome device further includes a handle operatively associated with the deployable assembly through a catheter by the handle in a one-handed operation for deploying the guide fins and cutting blades of the deployable assembly having respective outer diameters at each deployment position.