There is described a method of treating a lesion comprising: inserting a waveguide into a vessel of a subject, a lesion being present in the vessel and the waveguide extending longitudinally between a proximal end and a distal end； positioning the distal end of the waveguide adjacent to the lesion； generating a high amplitude mechanical pulse and propagating the high amplitude pulse from the proximal end to the distal end of the waveguide； and propagating at least a portion of the high amplitude pulse from the distal end of the waveguide to the lesion, the at least one portion of the high amplitude pulse propagating up to the lesion, thereby treating at least partially the lesion.
