The present invention is an atherectomy catheter with a hollow head. The head has a window with at least one internal bladed edge, a plunger, and an adjustable angle nose. The angle of the nose can be manipulated by the operator to apply pressure to an artery wall, thereby forcing the window and the window cutting edge up against a plaque target on the opposite side of the artery wall. The position of the plunger can be manipulated by the operator to open or close the window, thereby exposing or not exposing the bladed window edge, and optionally also pinching off dangling plaque fragments. Cut plaque enters the hollow catheter head through the open window, and is stored inside the catheter for removal from the body and subsequent analysis. In some embodiments, the catheter head may have optional sensors, or the plunger may also serve as a rotary cutter.