Shock wave balloon catheter with multiple shock wave sources

A method comprising:

• applying at least one voltage pulse to at least two electrode pairs of a device positioned adjacent a calcified lesion with a body lumen, the at least two electrode pairs mounted to an elongate member and located within a chamber filled with conductive fluid such that shock waves are produced in the conductive fluid and impinge on the calcified lesion, wherein the device comprises
• a first electrically conductive pathway electrically connecting a first electrode pair of the at least two electrode pairs in series with a second electrode pair of the at least two electrode pairs, the first electrically conductive pathway extending along the elongate member, a proximal end of the first electrically conductive pathway forming an electrode of the first electrode pair and a distal end of the first electrically conductive pathway forming an electrode of the second electrode pair, and
• second and third electrically conductive pathways that extend along the elongate member and are electrically connected to the at least two electrode pairs such that the shock waves are produced by the at least two electrode pairs when the at least one voltage pulse is applied to the second and third electrically conductive pathways.