Catheters for ablation and removal of occlusions from blood vessels are provided. Laser cutting systems and mechanical cutting systems are provided in catheter devices, the cutting systems operable to ablate, cut, dislodge, and otherwise remove occlusions within a blood vessel that may limit or prevent proper circulation. Pulsed aspiration systems are provided operable to remove ablated, cut, or dislodged material without excessive or unnecessary removal of blood and fluid. A helical or partially-helical inner surface structure is provided in the catheter operable to remove dislodged material. Distal features of the catheter devices comprise arrangements of laser ablative or mechanical cutting features that generally provide enhanced surface areas and cutting functions. Spiral or helical arrangements are provided to aid in cutting operations. Catheter systems comprise distal end features adapted to cut and remove at least portions of an occlusion that generally correspond to dimensions of an inner lumen of a catheter.
