Abstract: The invention constitutes a dilating catheter for blood vessels in which the catheter is constituted of a hollow radiopaque tube designed to be snaked into the blood vessel and includes a working guide inside the tube which is both longitudinally movable and rotatable. The working guide is in the form of a flexible guide which arcs out from the longitudinal axis at the distal end and rotate in three dimensions. The arc portion is designed to be located at a single point or at several points along the flexible guide, where a stenosis, i.e. vessel constriction, is located. The guide rotates to distend the tube and thereby the blood vessel at the stenosis location. The guide is connected to a rotational drive, through a speed reducer. It is also connected to a gauge which measures the mechanical resistance of the guide to rotation and to an integrating meter which integrates the mechanical resistance to rotation, to provide the physician with interactive control over the dilation process.