A catheter for aspirating occlusive formations (C) in a patients body includes an aspiration duct (14) with a distal suction opening (16). The aspiration duct (14) is to be brought to a subatmospheric pressure level (S) to aspirate an occlusive formation (C) through said distal suction opening (16). An unblocking duct (22) is provided to feed to the distal portion of aspiration duct (14) a pressurized fluid (S), to act in a proximal-distal direction on a block (B) formed in said aspiration duct (14). An occluder element (20) acts on said distal suction opening (16) to prevent the escape of the pressurized fluid from distal suction opening (16).
