A catheter system for imparting pressure to induce fractures at a treatment site within or adjacent a blood vessel wall includes a catheter, a fortified balloon inflation fluid and a first light guide. The catheter includes an elongate shaft and a balloon that is coupled to the elongate shaft. The balloon has a balloon wall and can expand to a first expanded configuration to anchor the catheter in position relative. The fortified balloon inflation fluid can expand the balloon to the first expanded configuration. The fortified balloon inflation fluid includes a base inflation fluid and a fortification component. The fortification component reduces a threshold for inducing plasma formation in the fortified balloon inflation fluid compared to the base inflation fluid. The fortification component can include at least one of carbon and iron. The first light guide is disposed along the elongate shaft and is positioned at least partially within the balloon. The first light guide is in optical communication with a light source and the fortified balloon inflation fluid. The light source provides sub-millisecond pulses of a light to the first light guide so that plasma formation and rapid bubble formation occur in the fortified balloon inflation fluid, thereby imparting pressure waves upon the treatment site.